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Flex
05-03-2009, 05:28 PM
Hey bros,

I was looking at some raised tops for a new member during my recup and I had a thought. Has anyone ever tried to raise the low side of a top during the process so that they are both the same height? Even the MP top is taller on one side than the other. Was this just a lazy recast or is there some reason for one corner to be higher?

nickleman60
05-03-2009, 07:25 PM
I believe it allows you to still use the stock i/c pipe, if it was straight across (even) then you wouldn't be able to get a good seal at the top and pipe connection. Just my guess at an answer.

Flex
05-03-2009, 10:58 PM
Perhaps you are right dude. I thought about it an it could be a factor but the IC can move and I think that both tubes should be able to pivot enough to account for it.

scxr7
05-03-2009, 11:26 PM
I was also thinking..If someone cut-n-weld a whole new top, I'd buy it. It seems to me that the stock or raised ic top is like a wall. once the air leaves the supercharger it hits the top hat, then when there is nowhere else to go, it goes to the ic piping. if someone fabbed up a piece of piping that is a 90 degree angle, it would let the air smoothly leave the supercharger instead of hitting the wall of the top hat.

That's my theory and I'm sticking to it:D

JACTcoupe
05-03-2009, 11:54 PM
I was also thinking..If someone cut-n-weld a whole new top, I'd buy it. It seems to me that the stock or raised ic top is like a wall. once the air leaves the supercharger it hits the top hat, then when there is nowhere else to go, it goes to the ic piping. if someone fabbed up a piece of piping that is a 90 degree angle, it would let the air smoothly leave the supercharger instead of hitting the wall of the top hat.

That's my theory and I'm sticking to it:D

Yeah, I would Imagine that working really well. Then you could run it the same size pipe as the IC pipe and it would flow way better then the stock hat. The only problem I see is hood clearance. But if you ran a cal hood it would work. I see it looking kinda like an 4.6 upper intake.

Shot I could make something out of steel. But not aluminum.
Has anyone else given this a thought?

Flex
05-04-2009, 01:24 AM
I don't know if the shape matters as much as its ability to exhaust the charge into the IC tubing. Keep in mind that it is exiting a triangular shaped opening and unlike an N/A engine (i.e. 4.6) it is being expelled under boost. As long as it is capable of flowing quickly, it shouldn't matter the initial shape.

I have already modded a raised top I purchased on the net by straightening out the bends at the front attaching bolts. This greatly opened up the diameter of the outlet. I think that if the top was also levelled, the flow improvement would be substanial.

JACTcoupe
05-04-2009, 06:43 AM
you got any pix of your top?

KMT
05-04-2009, 11:34 AM
>I think that if the top was also levelled, the flow improvement would be substanial.

The more you level the top, the more you increase the angle necessary to match the pipe to the IC - technically, improving flow at one point may mean hampering flow at the other...in reality, I'd think you would have to go a long ways before this became an issue, however.

JACTcoupe
05-04-2009, 12:16 PM
[QUOTE=Flex;812487]I don't know if the shape matters as much as its ability to exhaust the charge into the IC tubing. Keep in mind that it is exiting a triangular shaped opening and unlike an N/A engine (i.e. 4.6) it is being expelled under boost. As long as it is capable of flowing quickly, it shouldn't matter the initial shape.QUOTE]

Here is an illustration of what I mean. Im not talking about the shape of the tube but the bends. The stock hat is like a wall. 12psi of air blows up hits the top then is forced right. With something like in my illustration (Custom). 12psi rush is out the blower and smoothly bends to the IC tube.

Flex
05-04-2009, 04:01 PM
you got any pix of your top?

I will have to dig them up.

kenewagner
05-04-2009, 04:47 PM
[QUOTE=Flex;812487]I don't know if the shape matters as much as its ability to exhaust the charge into the IC tubing. Keep in mind that it is exiting a triangular shaped opening and unlike an N/A engine (i.e. 4.6) it is being expelled under boost. As long as it is capable of flowing quickly, it shouldn't matter the initial shape.QUOTE]

Here is an illustration of what I mean. Im not talking about the shape of the tube but the bends. The stock hat is like a wall. 12psi of air blows up hits the top then is forced right. With something like in my illustration (Custom). 12psi rush is out the blower and smoothly bends to the IC tube.

You mean like this

Ken

Flex
05-04-2009, 04:55 PM
Yours is obviously set up for an FMIC Ken. Did you ever compare that design to an ordinary raised top, such as the MP, for flow?

Mike8675309
05-04-2009, 07:23 PM
One thing to remember, the M90 does not pressurize the air inside the blower housing, it pushes air from the input to the output, with the pressure differential occurring at the output only when more air is being moved from one side to the other than the engine can consume.

Thus the air coming out of the blower isn't under pressure. The entire intake track from the back of the rotor lobes, to the back of the intake manifold valve sees essentially the same pressure when under boost.

kenewagner
05-04-2009, 07:27 PM
Yours is obviously set up for an FMIC Ken. Did you ever compare that design to an ordinary raised top, such as the MP, for flow?

No I havent. The majority of the guys who have gone down the mod road is the top really has little to no worth HP wise untill one gets to a high HP level. This top is setup up for side mounted tube. If I had done this for myself I just would have fabricated a tube to go to the stock located IC. Tops are realivity easy to fabricate. Most out there have diffrent ideas on what is best


Ken

Scott Long
05-04-2009, 09:05 PM
Every raised top I've seen has showed 0 hp increase on the dyno. I'll say that again.... ZERO HP INCREASE. :rolleyes:

fturner
05-04-2009, 09:13 PM
Dyno tests showed that a 3/4" raised top on a mildly modded SC showed no gains power wise. The only thing we saw was a small variance in blower outlet temperatures (we had a temp sensor on the top IC tube) by about 10 degrees or so which is nothing in the grand scheme of things. And that 10 degrees could have been anything. You don't see the temp change on the other side of the IC.

Fraser

scxr7
05-04-2009, 09:44 PM
so you're saying..I paid 180 bucks for a raised top, for nothing?? and guys buy 380 dollar MP tops for nothing as well?...

fturner
05-04-2009, 09:52 PM
Unless your future goals is an MPX or an AR blower, I would say yup, that money could have been better spent elsewhere. Is it going to hurt having it, nope.

Fraser

kenewagner
05-04-2009, 09:58 PM
so you're saying..I paid 180 bucks for a raised top, for nothing?? and guys buy 380 dollar MP tops for nothing as well?...


Thats what everyone is saying. Many mods that the money can be spent on that will show HP increases. One of the first things I did was build a 11/2" raised top and chromed it look nice but no change on the dyno

Ken

JACTcoupe
05-04-2009, 11:14 PM
No HP gain! Wow, I really didn't see that. But I guess it make senses. Well I guess I kinda got put in my place.:p HEHE

Scott Long
05-04-2009, 11:35 PM
I would not pay $380 for a top, no way. Maybe if i had a bunch of other bolt ons I'd get a top used for $100 and see if it helped, but it wouldn't be my first mod.

Lots of mods that should make power don't. There are some parts out there that just work.

I saw a car go from an MPX to a stock late model blower and it went 2 tenths quicker in the quarter mile than it ever did with an MPX. Not saying the MPX is bad, just interesting this was the outcome.

Same day (dayton SC meet this past weekend) another owners MPX ~~~~ the bed. I've known of a few MP blowers that fail, bearing seize up. Would I buy one.... well I'm a little leary now after seeing two fail with my own eyes. MP has been good about getting replacement blowers out to the owners so the customer service is good.

I'm surprised how many people jumped ship without really seeing what an S-port or ported late model blower can do. The MP inlet is a great piece and it does show gains on the dyno. That piece is worth the money in my book.

fturner
05-05-2009, 08:58 AM
In defence of the MPX before you go trashing it, what was the state of the rotor pack that was put into it? Were the front bearings brand new, and what was the tolerances of lateral play of the rotor pack, was it within tolerances? Was the rotor pack about 10-15 years old or even older?

As for less power than an s-port, other than they are better at low rpm than an MPX, how much OD did the MPX have? What type of IC does the car have and was it able to do its job to prevent spark from being pulled by high ACT's and knock sensor? Was it proven there was no belt slip? What fuel did the car run to prevent detonation? What was spark set at (assuming the car has a tune)? and I could probably come up with about another 20 questions etc.

I bet if you take an s-port and OD'd the sucker to 20% - 25% you'd see alot of failures as well, not that an s-port could be OD'd that much and still be efficient and not a heat pump.

If your going to make comparisons, you need to compare apples to apples and remove all the variables associated to draw a conclusion that in fact the MPX is a piece of junk.

Fraser

scxr7
05-05-2009, 03:33 PM
well, I have one now. guess I'll use it anyways. it can't hurt. plus, I'm running an mpx 25% o/d.

(edit) mpx-clone

Flex
05-05-2009, 03:45 PM
Scott,

But what other mods were associated with the raised top in those dyno sessions? No other mods + raised top, full exhaust plus double IC , camshaft & ported heads plus the last. There are many possible combinations that do not require the top and there may be a point where it is needed to improve.

Flex
05-05-2009, 03:47 PM
Dyno tests showed that a 3/4" raised top on a mildly modded SC showed no gains power wise. The only thing we saw was a small variance in blower outlet temperatures (we had a temp sensor on the top IC tube) by about 10 degrees or so which is nothing in the grand scheme of things. And that 10 degrees could have been anything. You don't see the temp change on the other side of the IC.

Fraser

Fraser,

Same idea as my question to Scott. What do you consider is mildly modded?

kenewagner
05-05-2009, 03:56 PM
Scott,

But what other mods were associated with the raised top in those dyno sessions? No other mods + raised top, full exhaust plus double IC , camshaft & ported heads plus the last. There are many possible combinations that do not require the top and there may be a point where it is needed to improve.

There are mods that make big diffrences and mods that dont show much of anything. Most guys who realize that the top is a zero improvement had many diffrent combinations so there is no secret formula or combination to making the top a good mod. A raised top for improved flow is probably at the end of a long list of mods that are needed to make HP. My opinion is you dont need a raised top untill your into the 300+ rwhp. Most guys just starting into the MOD game are a long way from there. If I was boosting 20 lbs of boost it would probably make sense, otherwise spend the money where it get you a better investment. For the cost of a top you could probably install a chip and get a dyno tune that will show a good bang for the buck. And it will be there when you keep adding HP on.

Ken

Flex
05-05-2009, 04:23 PM
There are mods that make big diffrences and mods that dont show much of anything. Most guys who realize that the top is a zero improvement had many diffrent combinations so there is no secret formula or combination to making the top a good mod. A raised top for improved flow is probably at the end of a long list of mods that are needed to make HP. My opinion is you dont need a raised top untill your into the 300+ rwhp. Most guys just starting into the MOD game are a long way from there. If I was boosting 20 lbs of boost it would probably make sense, otherwise spend the money where it get you a better investment. For the cost of a top you could probably install a chip and get a dyno tune that will show a good bang for the buck. And it will be there when you keep adding HP on.

Ken

Ken,

I see what your saying. I was just wondering where the point would be where it would be considered necessary. I think my brother's project is far beyond that point considering where it should be as far as power is conscerned.

XxSlowpokexX
05-05-2009, 04:35 PM
I remember back in the day...There was a comparison of the various raised tops being sold and thier power increase on the dyno. How accurate..WHo knows...

But just like any part there will come a time where it becomes a restriction be it a TB, MAF, Inlet, TOP, IC, Exhaust..... When these parts become the restriction is usually the debate.

So back to the top. It really is a ~~~. SO be it considered money wasted now....At some point it is a restriction which may cause turbulence, raised temps or just an overall bottleneck. So dont Fret..Its purdy

kenewagner
05-05-2009, 04:35 PM
Ken,

I see what your saying. I was just wondering where the point would be where it would be considered necessary. I think my brother's project is far beyond that point considering where it should be as far as power is conscerned.

My guesstimate is......Over 300rwhp at least. One might start to see an improvement. A cam and heads are needed to get over 300 rwhp so you start to see little restrictions along the way that can be removed for performance.

In my case I have a 76MM MAF and 75 MM TB and I am being told that is a restriction to my setup. I also have a poor mans headers and I need some better headers to reach the full potential. Its all about the right combination of parts and modifacations. You can likely have a 400 rwhp car with a stock top on it but than put a raised top on it might than see a big improvement over that 400 number. Its a game and he who makes the right discissions goes the fastest:D

Ken

Scott Long
05-05-2009, 06:43 PM
I'm not saying the MPX is junk. I'm just saying I've personally seen some fail. How many have been sold? How many have failed. Probably a small number compared to the total units sold. Plus MP has had good customer service on them replacing the parts.

As for the one that died this weekend, I don't remember what the rotor pack was from (I think late model or a GTP) but don't quote me. If the owner sees this thread and wants to identify himself and answer the questions, that's his decision.

As for the MPX running .20 slower in the 1/4 than a hand ported 94, well this was at a different track on a different day so it's not a true back to back comparison with an average of 3-5 runs each on the same track on the same day. So I see how it's apples to oranges sort of, but then again, it did post better numbers than it ever did with the MPX blower on any other track? Coincidence?? Most said the track didn't hook but this car ran good.

And for the top, not a good mod to do when you are just starting to modify your SC. Further down the road yes, but it wouldn't be one of my first 10 mods.

JACTcoupe
05-05-2009, 11:22 PM
OK then. Somebody needs to update the FAQ Forum, cuz It said in the how to get 25 to 30 more HP thread that the top plus exhaust and something else(Just going off memory) would give you something like 70 more hp. I thought that sounded a lil much.

And also for us noobies here. and I bet this has been discused.
So what would you but as yo top 10 first mod to more hp?

scxr7
05-05-2009, 11:54 PM
~~~.. I wrote a whole damn essay on the first 10 mods I would do, and I clicked backspace and it erased everything.. well I'm not going to write it all over again, so I'll just make a quick list.

1: exhaust
2:intake pipe/k&n filter
3:pulleys
4:weight reduction
5:shift kit (auto trans)
6: performance shocks,struts,springs,sway bar
7:trans cooler (auto) doesn't make it go fast, but keeps it lasting longer
8: 3.73 gears
9: tires/rims, to help get a better grip on the track or the road when you step on it.
10: DYNO TUNE! the tune will help the most.

fturner
05-06-2009, 08:55 AM
For starters...

1. Exhaust.
2. 76mm C&L MAF with 42lb injectors.
3. 75mm TB.
4. ported 94/95 blower at 10% OD.
5. Coated rotors for blower.
6. MP Chin spoiler.
7. All aluminum pullies (under drives not worth it in my opinion).
8. DIC with fan.
9. Extreme energy cam (now that I understand how they work ;) ).
10. A chip and tune.

That would get you in the 275rwhp (in an auto) range if not more. Stock airbox and tube and blower inlet plenum for the 94/95 blended to the blower is fine for that amount of power. This is also assuming that your car is running good in the first place. I don't know how often I've seen folks start throwing performance parts at their cars when the car is running like crap in the first place. I won't throw suspension up there because I feel it should get a refresh anyway because of the age.

Fraser

Flex
05-06-2009, 07:54 PM
For starters...

1. Exhaust.
2. 76mm C&L MAF with 42lb injectors.
3. 75mm TB.
4. ported 94/95 blower at 10% OD.
5. Coated rotors for blower.
6. MP Chin spoiler.
7. All aluminum pullies (under drives not worth it in my opinion).
8. DIC with fan.
9. Extreme energy cam (now that I understand how they work ;) ).
10. A chip and tune.

That would get you in the 275rwhp (in an auto) range if not more. Stock airbox and tube and blower inlet plenum for the 94/95 blended to the blower is fine for that amount of power. This is also assuming that your car is running good in the first place. I don't know how often I've seen folks start throwing performance parts at their cars when the car is running like crap in the first place. I won't throw suspension up there because I feel it should get a refresh anyway because of the age.

Fraser

No cold air kit for you Frasier? There goes 20 hp.

Scott Long
05-06-2009, 08:06 PM
What I've learned is that my mod list will look like this.

1. Catless exhaust and a good resonator and mufflers
2. 5% overdrive SC pulley
3. 42lb injectors and 255 lph fuel pump and 76mm MAF
4. Dyno tune (not taking chances with sampling tubes and what not. After seeing stock SC's run almost 100 duty cycle on the injectors I'm not messing with it)
5. BHJ balancer for piece of mind
6. underdrive pulleys
7. gears
8. good tires for drag racing (Quicktime Pro's or ET Street's)
9. late model blower
10. MP inlet plenum

Then after those first 10 mods I'd do a throttle body upgrade and intake. Then I'd get a bigger intercooler and when that's done I'd do more overdrive on the blower and jackshaft and tune it again.

Scott Long
05-06-2009, 08:09 PM
All aluminum pullies (under drives not worth it in my opinion).

I like the underdrives. They free up power and I noticed a seat of the pants increase in my car.

fturner
05-06-2009, 09:34 PM
No cold air kit for you Frasier? There goes 20 hp.

Flow testing the stock airbox and tube shows they are capable of supporting almost 500cfm.... my motor isn't capable of handling that much air yet so why waste the money, even though its getting close.

Where is your proof that a cold air kit will make 20 hp more?

Fraser

fturner
05-06-2009, 09:38 PM
I like the underdrives. They free up power and I noticed a seat of the pants increase in my car.

Show me dyno or ET evidence that underdrives compared to stock sized aluminum pullies nets more HP and torque on our motors.... until then, I'm happy knowing my alternator is doing its job at idle and so is my water pump ;) at stock speeds.

Fraser

Flex
05-09-2009, 04:14 PM
I think we are getting off topic here.

I thought about the raised top results posted. Without knowing the details, I have a thought as to why there may be no gain showing.

The idea of the increased opening reducing the work placed on the blower and thus reducing heat is sound. Unfortuantely the IC system is not one bottleneck but five.

1.) Top Hat
2.) Upper IC tube
3.) Intercooler
4.) Lower IC tube.
5.) Manifold inlet

Reducing the bottle neck at one point but not at the others would result in no effect. It merely pushed the restriction a little further down the line. Unless they were all removed, there would be no way to judge whether there is any potential gain.

My own inlet to the lower manifold was so restricted with casting flash at the opening to the lower IC tube that it was literally 1/4" smaller than it should have been.

Unfortunately, like everything on the SC, this means that all those points must be addressed at the same time in order to achieve the potential benefit from one part. In my own case, I cut apart and enlarged the IC tubes, ported the manifold inlet, enlarged the openings in the IC and installed the top hat at the same time.

Flex
05-09-2009, 04:23 PM
Show me dyno or ET evidence that underdrives compared to stock sized aluminum pullies nets more HP and torque on our motors.... until then, I'm happy knowing my alternator is doing its job at idle and so is my water pump ;) at stock speeds.

Fraser



Frasier,

It is a known fact the Ford water pumps are prone to cavitate. Past a certain speed, a water pump impeller becomes ineffectual and just increases the cavitation factor reducing the efficiency of the cooling system and increasing hp loss to drag. As long as the speed is not drastically reduced, slowing down the waterpump aids the cooling system to be more efficent.

fturner
05-10-2009, 08:09 AM
Frasier,

It is a known fact the Ford water pumps are prone to cavitate. Past a certain speed, a water pump impeller becomes ineffectual and just increases the cavitation factor reducing the efficiency of the cooling system and increasing hp loss to drag. As long as the speed is not drastically reduced, slowing down the waterpump aids the cooling system to be more efficent.

Out of curiosity?

How much of an RPM difference are we talking about? A 100 or 200 rpm slower? On our stock motors that reach peak hp at about 4800, does that make that much of a difference? Do our water pumps cavitate when the motor runs at 5000 rpm's?

Where da proof? Until someone can prove that underdrives give me more hp and better ET's at the track that are measurable, I'd rather be comfortable knowing that I'm getting as much coolant flow and charging as possible when the car is idling or when I'm in stop and go traffic on a hot day ;) with the a/c running.

Fraser

ps Also to clarify, I'm also talking about comparing a full set of stock sized aluminum pullies to a full set of underdrive pullies in aluminum... not a comparison to the stock steel pullies.

fturner
05-10-2009, 08:17 AM
I think we are getting off topic here.

I thought about the raised top results posted. Without knowing the details, I have a thought as to why there may be no gain showing.

The idea of the increased opening reducing the work placed on the blower and thus reducing heat is sound. Unfortuantely the IC system is not one bottleneck but five.

1.) Top Hat
2.) Upper IC tube
3.) Intercooler
4.) Lower IC tube.
5.) Manifold inlet

Reducing the bottle neck at one point but not at the others would result in no effect. It merely pushed the restriction a little further down the line. Unless they were all removed, there would be no way to judge whether there is any potential gain.

My own inlet to the lower manifold was so restricted with casting flash at the opening to the lower IC tube that it was literally 1/4" smaller than it should have been.

Unfortunately, like everything on the SC, this means that all those points must be addressed at the same time in order to achieve the potential benefit from one part. In my own case, I cut apart and enlarged the IC tubes, ported the manifold inlet, enlarged the openings in the IC and installed the top hat at the same time.

Unless someone has the skills like you do that can cut-n-weld and mod everything at the same time, spending that kind of money on a raised top for a stock to midly modded car shows nothing of benefit. We measured boost and temps and I have time slips to show that a raised top was of no benefit to the car. Thats up to $200 or more that can go towards fixing the suspension, a chip, a DIC, or a chin spoiler that will benefit the car.

With all your work, where are the datalogs and timeslips etc that show the improvements? Don't take this as me doubting you or your work, but if your going to discuss points, you need facts to back them up ;).

Fraser

TinManSC92
05-10-2009, 12:57 PM
HEY, FLEX! you should try the 10% underdrives on your car and don't mess with the blower for the moment. you will notice a huge difference. it deffinately did mine and keeps everyone snuggly in there seats.:D

other then that i say start with a built eng. first and ignore the supercharger for now....... for all the time and money it's just more economical to me. but, again that's just me. and thanks again for your previous help. peace out!

Flex
05-10-2009, 03:54 PM
Unless someone has the skills like you do that can cut-n-weld and mod everything at the same time, spending that kind of money on a raised top for a stock to midly modded car shows nothing of benefit. We measured boost and temps and I have time slips to show that a raised top was of no benefit to the car. Thats up to $200 or more that can go towards fixing the suspension, a chip, a DIC, or a chin spoiler that will benefit the car.

With all your work, where are the datalogs and timeslips etc that show the improvements? Don't take this as me doubting you or your work, but if your going to discuss points, you need facts to back them up ;).

Fraser

Frasier,

Currently I have no way to datalog. You know that because I enquired on your stuff.

I am not saying that a raised top MUST add power. What I am saying is the perhaps it doesn't because it is just one cog on the wheel and unless they are all eliminated, it doesn't help.

As for gain or not without timeslips dyno's etc, I have only one way to determine improvement. Prior to the changes, I had a steel 10% pulley and underdrives. Car squaked the tires pretty good. After the hat, IC tubes modified IC and ported manifold inlet, I could easily lay 20-30 ft of rubber both wheels. I'd call that an improvement.

Flex
05-10-2009, 04:04 PM
HEY, FLEX! you should try the 10% underdrives on your car and don't mess with the blower for the moment. you will notice a huge difference. it deffinately did mine and keeps everyone snuggly in there seats.:D

other then that i say start with a built eng. first and ignore the supercharger for now....... for all the time and money it's just more economical to me. but, again that's just me. and thanks again for your previous help. peace out!

Hey dude, my car came with one and I have two aluminum ones I picked up. I mod the superchargers myself via welding and porting so it is cost of gas and wire.

I have many different sizes of injector, MAF, cam etc. so I can build many different combinations without issue. Just labour and gaskets.

I am in the process of building a motor for my brother's SC and that is not cheap and the headaches just keep piling up.


This year for my own car, I have these parts to go in. Walbro 255 hp pump with late model tank and 55 lb injectors, long tube headers and full stainless exhaust with Magnaflow resonator and flowmaster mufflers, camshaft, 1.8 rr, a welded and S-ported oval with a highly modified inlet to match (just sent one to Steve Mazza to test), 75 mm TB, 80 mm C&L, MP cold air,and if I really want to go for broke, a brand new rectangular port still in the box.

To top it off, I will invest in one of Frasier's chip and programs to be able to do all that neat data logging and ECM tweaking everyone is so giddy about. We will need one for my brother's car anyways.

Flex
05-10-2009, 04:08 PM
I am also currently trying to re-invent the wheel, so to speak, as far as the raised top issue is concerned. I have take a different approach to the traditional raised top that will incorporate another part.

Hopefully that part, along with another for the manifold inlet, will help isolate the IC system from heat and limit the heat soak into the components.

kenewagner
05-10-2009, 09:43 PM
I think we are getting off topic here.

I thought about the raised top results posted. Without knowing the details, I have a thought as to why there may be no gain showing.

The idea of the increased opening reducing the work placed on the blower and thus reducing heat is sound. Unfortuantely the IC system is not one bottleneck but five.

1.) Top Hat
2.) Upper IC tube
3.) Intercooler
4.) Lower IC tube.
5.) Manifold inlet

Reducing the bottle neck at one point but not at the others would result in no effect. It merely pushed the restriction a little further down the line. Unless they were all removed, there would be no way to judge whether there is any potential gain.

My own inlet to the lower manifold was so restricted with casting flash at the opening to the lower IC tube that it was literally 1/4" smaller than it should have been.

Unfortunately, like everything on the SC, this means that all those points must be addressed at the same time in order to achieve the potential benefit from one part. In my own case, I cut apart and enlarged the IC tubes, ported the manifold inlet, enlarged the openings in the IC and installed the top hat at the same time.

Its nice brain storming but I can say that
1 I had a lower intake with huge inlet and matching plenum
2 A FMIC
3 Custom IC tubes
Built the top. No change. At the time I had a stock internal engine, lots of bolt on mods. No improvement. About 230 RWHP. The top is likely a decent mod at a lot higher level as said before but at what most guys levels. Its a waste. It is still better to spend money in the beginning on mods that will make sense. At some point after internal modifacations a raised top might make sense. At this point on my car the top became a mute issue but prior to the twin screw it at least looked good:D

Ken

JACTcoupe
05-10-2009, 10:23 PM
OK so underdrive pulley and raised top have been stated to give no HP gains on paper. But Ok So what about throttle response or the fact that is give such lil gains that it doesn't show up at the wheels. Like maybe to 1hp to the crank. Yes Thats not worth the 2-300 bucks just saying. But throttle response is nice, The motor turns up a lil smoother and a lil faster. Just makes diving a lil more enjoyable.

XR7 Dave
05-10-2009, 10:29 PM
What some of you are alluding to but no one has really said (probably partly because of not knowing), is that despite what people think regarding what a part looks like and what seems good, the Ford system is originally pretty decent with all parts matching each other pretty well.

The stock intake system (the naturally aspirated side) flows about 500cfm. Fraser indicated that he has calculated about 500cfm at his power level which is in the 250-275rwhp range. He has thus determined that his intake and power level match pretty well.

Now what people are ignoring at this point, is that the rest of the system, SC top, IC tubes, return plenum, and intake manifold all flow about 500cfm - naturally aspirated. But they aren't naturally aspirated. At 15psi boost the air flowing through those tubes is at 2x normal pressure and therefore takes up less space than normal air. This means that the flow capability of the IC tubes etc. dramatically exceeds the needs of the motor. There simply isn't anything to be gained by increasing their flow capability.

Now improving the IC - YES! The IC only flows about 240 cfm naturally aspirated so it is by far the biggest restriction in the system. Anyone who has not improved their IC will gain NOTHING from improving any other part of the system. Even with a much better IC, you still have to exceed the volume requirements of whatever your intake air volume is @ 15psi to make any improvements on the pressurized side of the system.

Do the math. Somebody tell me the amount of space air compressed to 15psi takes and how much cfm will be consumed compared to atmosphere and then use that to determine how much CFM your motor will have to process before you exceed the capabilities of a stock IC tubing system....

XR7 Dave
05-10-2009, 10:31 PM
OK so underdrive pulley and raised top have been stated to give no HP gains on paper. But Ok So what about throttle response or the fact that is give such lil gains that it doesn't show up at the wheels. Like maybe to 1hp to the crank. Yes Thats not worth the 2-300 bucks just saying. But throttle response is nice, The motor turns up a lil smoother and a lil faster. Just makes diving a lil more enjoyable.

Nobody can say that UD pulleys don't make power. They do.

Raised top does nothing on a 250rwhp engine. If you feel a difference it's all in your head. If spending money on a top makes you happy, then do it.

Neither of these items make the motor run any smoother but UD pulleys will help it rev quicker and make more power.

TinManSC92
05-10-2009, 11:37 PM
you can certainly tell that Flex is from an oil rich province. wish i had that kind of time to do all those experiments. and, most of all, those deep pockets to through all that stuff at my car. :(:(:(:

TinManSC92
05-10-2009, 11:43 PM
:eek: couldn't spell throw. sorry.

JACTcoupe
05-11-2009, 09:38 AM
Nobody can say that UD pulleys don't make power. They do.

Raised top does nothing on a 250rwhp engine. If you feel a difference it's all in your head. If spending money on a top makes you happy, then do it.

Neither of these items make the motor run any smoother but UD pulleys will help it rev quicker and make more power.

Lol you got to feel it in your head. Shot cuz if you spend 300 buck for nothing you would be upset.
But Im truly glad this thread got brought up. Cuz other wize I would have bought a top as one my first mods. Cuz most of the way everyone talks, it like one of the first thing one should do.

So in turn I think you guys for some great info.:D
But no mod for me till my CEL Light is off and I have a none slipping clutch.

scxr7
05-11-2009, 01:22 PM
yeah, its a shame this thread didn't start one week earlier. could've saved me 200 bucks:(

Flex
05-11-2009, 02:25 PM
David,

You now have me confused on the purpose behind this. I thought the idea of an enlarged IC system was to reduce the load on the supercharger thus making it run cooler and transferring less heat into the air charge not about airflow.

XxSlowpokexX
05-11-2009, 06:16 PM
I would work on the restrictions inlet wise first. TB, MAF SC inlet. THE IC is also a major bottleneck. Not only does it not get enough air through its core but its a restriction as well. As far as the IC you theoretically want an IC that will flow enough to not be a restriction as well as have enough surface area to sufficiently cool the ACT. IMO our IC is barely good enough for our stock setup let alone one pushing more boost on a hot summer day.

Our lower IC tube is very close to the exhaust manifolds. I generally wrap a portion of it with a thermal reflective tape to avoid absorbing that extra heat.

And I have always noticed a difference with UD pulleys installed on an SC..It salway smy first mod as well

XR7 Dave
05-11-2009, 07:23 PM
David,

You now have me confused on the purpose behind this. I thought the idea of an enlarged IC system was to reduce the load on the supercharger thus making it run cooler and transferring less heat into the air charge not about airflow.

The load on the supercharger and the flow capability of the parts it is flowing air into are interlinked and inseparable. They are one and the same. If you remove all restriction from the blower then it won't create any boost and will draw comparatively little power to spin. Putting a load (restriction) in front of the blower is how you make boost.

Ideally the motor itself would create the biggest restriction. If you want to improve the system, then start with the item of greatest restriction (aside from the motor) which in this case is the IC, and work upwards from there. Not knowing which part is the greatest restriction limits your ability to target the biggest offenders to generate the greatest results for your efforts.

fturner
05-11-2009, 07:56 PM
On the subject of UD's... we know going to aluminum pullies saves weight as far as rotating mass goes which allows the motor to accelerate quicker, which I noticed quite a bit of difference as well...

Now, I want someone to show me by testing that running UD's gives you gains over running stock sized aluminum pullies which is what I have. If I switched to UD's from my current setup, how much of a gain am I going to see at the track and/or the dyno? If I'm going to see a difference of 0.5 seconds in the 1/4 or another couple of mph in my trap speed then I'll switch.... but if I'm only going to see 0.01 seconds and less than 0.1 mph with trap speed, then no thanks, I'd rather know I'm getting good coolant flow and good battery charging at that time while the a/c is running at idle in those hot days stuck in traffic ;).

Butt dyno's are not calibrated well enough for this type of testing.

Fraser

XxSlowpokexX
05-11-2009, 09:09 PM
I hav enever had cooling issues or charging issues with teh UD's...If I had a system that drew allot of power however I dont think Id dpo it. I know on my 5.o I had gotten 12rwhp

Regul8r
09-17-2009, 04:28 PM
IF I am reading all the info on this thread correctly...

1. 500CFM is what our 3.8 breathes on the intake side
2. 94/95 STOCK intake flows 500CFM... no need to increase MAF, Throttle body, or bigger tube. Cold air is better but not needing bigger tubes just fresh cold air?
3. SC, pushes air up and out... Raised top vs stock hat... No difference
4. SC output cast tubing lines capable of 500CFM which is TWICE what the SC puts out because forced air is 1/2 as much as regular? MEANING 500CFM in, compressed/SC'd is 250CFM of air?
5. Stock IC flows 240CFM... HHHMMMMM sounds like stock IC is the choke point! It is only capable of HALF the line flow?
6. IF we opened up the IC to match the line flow(500CFM) then it would match the intake flow?
7. BUT opening the IC to 500CFM means the STOCK Pullied SC is not FORCING air! The engine needs about 500CFM, the IC Lines and new IC flow 500CFM and the intake sucks 500CFM, sounds like a fully compatible system.
HOW MUCH CFM does the stock SC PUSH at what RPM?

1. Completely blow out the exhaust as stated to create as close to ZERO back pressure.
2. Replace Stock IC with one that flows 500CFM
3. Ensure intake side is clean and flows (High Flow Air Cleaner), the system and tubing flows 500CFM so the Air Cleaner has to let it!!!
FULLY COMPATIBLE PERFECT WORLD ENGINE... In flow matches outflow with no restriction!

Tricky part...have to spin the SC faster to now COMPRESS/Charge the Air through the tubes. Doing that means more heat, more heat means less efficient and less power... so the happy medium is 500CFM IC that can cool a super hot SC air flow ALONG with somehow cooling the SC itself?

As for all theother goodies... injectors, fuel pumps, etc... the kwy is to SC more than the engine can handle to make it SUPERCHARGED other wise it is just pushing air at the same speed the engine is using it?

OK OK OK let it rip!
I may be WAY off base!

But the one thing I see we ALL agree on... OPEN THE EXHAUST!!!! Let 500CFM OUT of the motor! Then you will see what restriction REALLY does to the boost level! I like the article research I saw and read about the exhaust restriction... I am putting a step UP adapter from stock manifolds to 2 1/2 down tubes with high flow cats, then a Borla 2-1 (2x 2.5 inlet/ 3in outlet) resonator, 3 inch pipe back to dual 2 1/2 tail pipes(Mufflers with/without or which ones still yet undecided). Actually see no real need to do 2 1/2 AFTER a 3in single tube... dual 2 1/4 pipes flow a little more than the 3in. But hey its a start to see where I am at with EXHAUST cleared out and flowing the best I can get it without being obnoxious droned or ricy.

THEN start looking at IC and pullies. Also looking to externally cold air intake or Ram Air of some sort(YES I read the research referred to here on Ram Air as well) I have some ideas to get a GAIN out of it. But hey THAT is a whole nother thread!

Bottom line... no raised top YET!

thunderkid84
09-17-2009, 06:53 PM
i think you're getting way in over your head.

just know that the ic is the most restrictive part AFTER the sc.

as for your step up on your manifolds....remember that as the exhaust gas expands, its velocity will slow down. so goin from the less than 2" outlet on the stock manifolds (unless you plan to port them) to 2.5" is gonna slow the gasses down when exiting the manifold.

also, getting 2.5" pipe to make a good seal with the manifold is difficult.

Ryan A Harris
09-18-2009, 06:06 PM
Back when I was making pullies I spent many hours on a dyno swapping out pullies to compare many different set ups. On my car at that time, with the set Ii was testing on the, underdrive pullies didn't do much. A few ponies, but not huge improvements. On the stock diameter aluminum pullies I picked on average 10-14 rear wheel horse power, on pretty much any set up. I also ran every make and model of underdrives on my car that was possible. I always had charging & cooling issues. My car was a daily driver and at that time saw the road in the winter months. So in my book, I'll always go for the stock diameter aluminum pullies.

As for the top, I agree not a HP increase item at all. But take a look at some of the high power SC's or the fastest lists, its on almost every car.:confused: I wonder why these guys don't take off this part & sell it for something more worthy?:confused:

I have 2 SC's both of which I have had raised tops on. Niether of which I paid a cent for, but I'm not getting rid of them. I guess there can be something said for peer pressure, or wanting to fit in with the rest of "gang"

fturner
09-18-2009, 07:10 PM
The stock SC won't be flowing 500cfm either. My car is making about 300rwhp and its flowing about 580cfm.

A stock SC would probably flow about 350-400 depending. Remember that air pressure and temperatures directly affect cfm.

Fraser

Wagonman88
09-22-2009, 10:37 AM
As for the top, I agree not a HP increase item at all. But take a look at some of the high power SC's or the fastest lists, its on almost every car.:confused: I wonder why these guys don't take off this part & sell it for something more worthy?:confused:

I have 2 SC's both of which I have had raised tops on. Niether of which I paid a cent for, but I'm not getting rid of them. I guess there can be something said for peer pressure, or wanting to fit in with the rest of "gang"

Basically the only benefit I can see with a raised top would be it gets the air on a straighter path before entering the IC piping. The same as a high rise intake manifold or even a throttle body spacer would do for a NA motor.

However, being the air is forced through, this type of modification would only wield you power if you were pushing LOTS of CFM through it. Like 800+ in my opinion. Which means probably around 25lbs of boost, where that much air would literally be "hitting a wall" before having to turn towards the IC.

These stock IC setups have so many flow issues, but they work. Provided you aren't making HUGE power numbers, a knife edged and polished top would wield you more, and it's a free mod :) The next step would be to replace that cold pipe after the IC. With it squooshed like that I can't see it flowing very well, however it is on par with the rest of the setup, so again... if pushing more CFM, it will be a worthy thing to change.

On a side note, when air is forced to turn directions and do things it doesn't want to do it creates heat. With a smoother flowing top hat, theoretically the IC would have to do less work. The amount of difference would be minute, but I'm looking at this with a physics mindset.



Jeremy

P.S. The raised top is kind of a "me-too" part. "Oh you have a raised top, me too!" :)

S_Mazza
09-22-2009, 03:32 PM
Regul8r, the thing about freeing up the IC restriction is that you don't need to spin the SC faster at all to make the same boost. What the restriction does is prevent that boost from making it to the intake valve. It's "backed up" in front of the IC, so to speak. So it never registers on your boost gauge in the first place.

The trick is to make an IC that offers the least restriction possible while still cooling the air sufficiently. I mean, you could use a straight tube with some fins on the inside and outside and get an amazing near-zero pressure drop ... but you would also have an amazing near-zero temperature drop!

If you get a less restrictive IC that still cools effectively, then you will probably see more boost, not less. Although even if the boost pressure reading went down somewhat, that could be accounted for by a lower temperature of the air charge. The "boost" number is actually kind of arbitrary without accounting for air temperature ... it's all about the density!

David Neibert
09-22-2009, 04:48 PM
Hindsight is 20/20....:rolleyes:

Ten years ago most of what people were doing to get more power out of their cars was experimental and done by applying what worked well on other motors. If someone reported good results everyone jumped on board, mainly for lack of options.

We didn't have custom chips or the ability to monitor data and create custom tunes...we are just now (in the past year) gaining access into many areas of the EEC. You guys who are just now starting to mod your SCs have it a lot better than we did, mainly because of all the stuff we tried doing in the past.

David

baer198
09-22-2009, 04:50 PM
Hindsight is 20/20....:rolleyes:

Ten years ago most of what people were doing to get more power out of their cars was experimental and done by applying what worked well on other motors. If someone reported good results everyone jumped on board, mainly for lack of options.

We didn't have custom chips or the ability to monitor data and create custom tunes...we are just now (in the past year) gaining access into many areas of the EEC. You guys who are just now starting to mod your SCs have it a lot better than we did, mainly because of all the stuff we tried doing in the past.

David



very true, and I'm thankful for it, so thanks fellas:D