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Mike8675309
07-13-2010, 08:58 PM
If you haven't heard yet or got the hint from the signature below, I took a trip to a local Dynojet Dyno to dial in the upper reaches of my maf curve, see if Methanol could give me some rpm since I have fueling issues, and see how much power this baby can crank out.

#1 was achieved.
#2 I learned a bit.
#3 turned out it's enough, at least for now.

Max HP is 441.40 5450rpm :)
Max Torque is 462.89 @ 4500rpm http://i8.photobucket.com/albums/a23/tcw_fort/emote/toocool.gif

The run started at 2150rpm
Torque was over 400ft/lbs from 2600rpm and onward.
Hp hit 400+rwhp at 4550rpm and onward.

This run was on E85 + Methanol. Outside temp was 88.9f, with pressure at 29.39inmg

AFR was about 11.2 or lambda .76. They dyno operator had done many E85 cars and his experience was that it could run leaner. Something for me to investigate further once the fueling is worked out.

Timing was progressive using the Spark - WOT Advance vs RPM.
2500rpm - 14 degrees (stock is 17)
3200rpm - 18 degrees (stock is about 20)
4000rpm - 24 degrees (stock is 24)
5000rpm - 26 degrees (stock is 26)

As you can see, I did not change timing much from stock. I just didn't see the point until I have fueling figured out, wasting time on a dyno. (Prior to e85, timing was 8,12,15,18,20 for running on 91octane)

Methanol was set to come on about 4580 which is about where the fuel rail started loosing pressure. Full meth was set to come on below 5v.
By 4820rpm the methanol was starting to loose the battle to progressively worse fuel pressure.
I may have a regulator issue on top of everything else.
Max fuel pressure is achieved (55.02psi) at 3.5 psi of boost(2750rpm). :(
At 4800 rpm, fuel pressure has dropped to 39.6 (uh huh...) :eek:
When we let off at 5488 boost is at 18.997 (call it 19) and fuel pressure had squeaked back up to 40.18. (injector duty cycle is 103)
Air Fuel ratio was still safe there, but heading north fast.

In 2008 this same motor, minus the blower and intercooler, and with an SCT tune maxed out at 275rwhp and 343lb/ft on meth. Then the motor had a stock 89 M90 blower (over 100,000 miles on it) and a stock intercooler (no fan).

Here is the chart. Note that this run was the last run (#9) and was after a 30 minute cool down (the dyno guy had to drop someone off). Prior to that cool down the last run was at 430rwhp and 442 torque. The difference being the cool down, and increasing timing at 3200 by 1 degree, 4000 by 3 degrees, 5000 by 2 degrees. On this run, coolant temps started at 180 and ended at 184. Air fuel temps started at 100 and ended at 112 (no ice used).
http://media.motortopia.com/files/cars/album_2010work/4c3cff7312e34/tn_full_2010-07-13_142848jpg_Thumbnail1.jpg (http://www.motortopia.com/photos/545551)

So lots of typing... I tend to over analyze things quite a bit. I really need to get the garage updated with all my information for this car. I built the motor in my basement with significant assistance from many people on the forum here and Dave Dalke (xr7 Dave). This motor was built from the beginning for an Autorotor. Thus the 160% power improvement in swapping the blower and intercooler. Dave Dalke has be instrumental in choosing the lower end components, specifying a cam, building the heads, building the blower kit, and he has been doing all tuning on this car and assisted me in getting started with the Moates Quaterhorse. Fraser (Fturner) recently helped me with some remote tuning on the car and information after upgrading to 80lb/hr injectors and more info on the Quarterhorse.

Unfortunately I wonít get to back up these numbers on the track too soon, as my trac-lock still needs to be replaced. unless I win one at the Car Craft Summer Nationals this year, I wonít have a replacement until next season. So Iíll be at the track at least twice this year but expect to have terrible 60ft times, and be stuck in the 13ís.

This winter Iíll take care of the fueling issues with a completely new fuel system (new lines, adjustable regulator, and some sort of fix, either dual fuel pumps or boost a pump).

Oh.. and btw... Iíll be building some headers this winter, as Iím still running stock t-bird exhaust manifolds.
http://i8.photobucket.com/albums/a23/tcw_fort/TBIRD/2010-06-20150451.jpg

90blkbrd
07-13-2010, 09:06 PM
Congratulations! That is an amazing feat for stock exhaust manifolds.

I can't wait to see what your car can do with a better fuel system.

David Neibert
07-13-2010, 09:33 PM
Mike

Those are excellent results, congrats !! In addition to the fuel system upgrades you mentioned, an 85mm TB would be a good investment.

David

CMac89
07-13-2010, 09:49 PM
Wow, Mike, those are great results. I'm sure you understand, but the injectors are high on duty cycle from a lack of fuel volume. You have a decent amount of power on the table with getting the fuel system up to par and running more timing. Headers, too.

Thomas A
07-13-2010, 09:51 PM
Very impressive! How does it drive out on the street? Max boost?

Thomas

Mike8675309
07-13-2010, 10:43 PM
yep, lots of side effects of not enough fuel pressure available. The nice thing about the 80's is that they can open up that pw to get me into usable rpm until I can fix the fuel system. The 60's would have never made it.

Driving on the street is just like it ever was. I've been struggling some with idle (unrelated to the e85) which has been hashed out in the tuning forum. Boost right now is RPM limited. I'll keep myself at a limit of 5000rpm until I have fuel figured out, which has boost at 18.8PSIg. At 4000RPM boost was 17.6psig. So if the change is linear, at 6000 rpm I'd be right around 20psig.

I have a back up tune for 91 octane should I end up in an area without E85. Just about every city in Minnesota has E85. Going to Iowa gets tough to find. If I go to a track and can't get E85, I'll run race gas which I'll have to adjust the tune for at the track. But that's the point of having a quarterhorse and wide band.

And yes, an 85mm would be good. Unfortunately, the budget Nazi is not allowing any more parts purchases for the car. I had to do the dyno trip on the down low, and just ask for forgiveness. Got the header kit purchase coming up and i wanted to get an idea of where my power is at so I could decide what I need.

decipha
07-13-2010, 11:31 PM
Here you go Mike,

93 5speed
2.0L AR
valves 1.84 I & 1.57 X
218 I / 224 X .555 -114
9:1 Forged
75mm t/b
80# squirters
80mm C&L MAF
Snow Meth
Liquid/Air Inter-cooler

kenewagner
07-14-2010, 07:22 AM
With that kind of power why would you think you are going to run in the 13s:confused: I would love to have your numbers but I always seem to have a gremlin or two on the dyno, messing things up. Great numbers, Im sure your feeling that everything you have done is starting to pay out.

Ken

Mike8675309
07-14-2010, 07:39 AM
With that kind of power why would you think you are going to run in the 13s:confused:

My rear diff needs new clutch packs. (i am going to get a new diff, auburn pro)
Thus I can't get the power to the ground. Last fall at the club clash I was running 13.5's @ 113mph. 60fts were 2.3-2.4 with wheel spin through 1st, and into 2nd.

Once I get the diff fixed, and some new drag tires, I shouldn't be in 13's anymore.

My car remains a cluster of compromises driven mostly by budget. Thus fuel issues, and bad diff still hang around. I had high expectations for my current fuel system up until the past 12 months and seeing the results that others have been having.

rzimmerl
07-14-2010, 08:09 AM
Congrats on the great numbers, looks like its going to be the year for big numbers.

What fuel system upgrades did you do this year besides the 80lb. injectors?

pablon2
07-14-2010, 08:19 AM
Congrats Mike! I had no idea I was touching such a beastly engine this past Sunday. :D I'm glad to see you put my methanol to good use! Looking forward to seeing the 'final' numbers once the outstanding issues are fixed. Either way, you should be uber happy with where it is right now.

Kurt K
07-14-2010, 08:56 AM
Congrats on the big numbers. Now get some numbers at the track:D

kenewagner
07-14-2010, 09:06 AM
My rear diff needs new clutch packs. (i am going to get a new diff, auburn pro)
Thus I can't get the power to the ground. Last fall at the club clash I was running 13.5's @ 113mph. 60fts were 2.3-2.4 with wheel spin through 1st, and into 2nd.

Once I get the diff fixed, and some new drag tires, I shouldn't be in 13's anymore.

My car remains a cluster of compromises driven mostly by budget. Thus fuel issues, and bad diff still hang around. I had high expectations for my current fuel system up until the past 12 months and seeing the results that others have been having.

Well you should be happy with you combination of compromises. I have tried to have a well balanced package of well thought out combinations of performace modifacations and am still behind everyone. I cant even get into the 400 club:( The nice thing for you is you get to know you have only one way to go and that is up in power;)

Ken

Ira R.
07-14-2010, 09:13 AM
Great job Mike! Don't you just love it when a plan comes together :D

Ira

ricardoa1
07-14-2010, 09:30 AM
My rear diff needs new clutch packs. (i am going to get a new diff, auburn pro)
Thus I can't get the power to the ground. Last fall at the club clash I was running 13.5's @ 113mph. 60fts were 2.3-2.4 with wheel spin through 1st, and into 2nd.

Once I get the diff fixed, and some new drag tires, I shouldn't be in 13's anymore.

My car remains a cluster of compromises driven mostly by budget. Thus fuel issues, and bad diff still hang around. I had high expectations for my current fuel system up until the past 12 months and seeing the results that others have been having.

Good Job Mike. Great Job working thru it. Ive been unable to do anything about fuel myself. I can only imagine whats going on with your car trying to run Ethanol on the 255 pump.
I guess ill keep an eye on what you do for more fuel. I jump on board when you do.

Mike8675309
07-14-2010, 09:57 AM
Fuel system consists of:
Modified rail (not for performance, just to fit the blower)
Stock Regulator
Stock Fuel Lines
Walbro 255lph High Pressure in tank pump
Direct Battery power for fuel pump. (did this last weekend and only gained 2 psi across the board)

For sure the fuel pump is not able to keep up, as indicated by the extra 2psi gained with the improved power to the pump.

Secondly, I suspect a regulator issue, as I'm just not seeing the fuel pressure I would expect on a 1:1 boost/pressure scale that should be happening. (I data log fuel pressure)

After this winter, I'll maybe have new rails, will have a new adjustable regulator, new fuel lines, and some sort of new fuel pump setup. Either dual pumps in the tank, or an external boost pump like Vortech supplies with their blowers.

A note. At the start of the run, the EEC-IV will report seeing battery voltage of 13.3v. At 5000RPM, EEC-IV reported battery voltage is down to 12.5v. That in and of itself will have an impact on fuel pump performance as these pumps are such that they flow higher at higher voltage, less at lower voltage with most having flow rates specified at 13.5v.

Ken, what kind of issues do you have remaining. I recall an issue with MAF acting up. Is that it? If you are just dealing with little things, and you have the QH installed with a wide band. I'm more than willing to come down for a weekend and help you track down and solve some of this. Heck, if you just need an extra hand, I'll come down and help you out.

rzimmerl
07-14-2010, 10:28 AM
I wonder how effective the external boost pump would be? It seems to be the easiest method to supply extra fuel vs. a dual pump setup if it will work properly, as it seems to work for many other vehicle platforms. That would also be an opportune time to upgrade to AN feed and return lines, along with a remote regulator.

ricardoa1
07-14-2010, 10:39 AM
On my car albeit I have 60#s I have the fuel pressure jacked up to 51 or so But I dont see it being linear either on my car.
An external pump might be the solution but I dont have funds to allow me to experiment. So I need a proven solution. If I can get away without using 80lbs then all the better.


Also Mike do you feel you are running very aggressive tuning down low......I been advised not to run so much spark on a modified vehicle. I know it shows great power numbers but stock spark tables are pretty dangerous for a modified car. So Ive been told.

David Neibert
07-14-2010, 11:35 AM
I wonder how effective the external boost pump would be? It seems to be the easiest method to supply extra fuel vs. a dual pump setup if it will work properly, as it seems to work for many other vehicle platforms. That would also be an opportune time to upgrade to AN feed and return lines, along with a remote regulator.

Yes..at our power levels, adding the external booster pump would work. It won't flow anymore than the 255 high pressure pump, but it will help to maintain flow/pressure at high rpms/boost. Adding a voltage booster will also work, and it's even easier to install. Main problem with the external booster pump is more noise and heat.

I'd like a larger pump in the tank or dual pumps in the tank, but I'm still saving the external pump option as a last resort.

David

Toms-SC
07-14-2010, 11:39 AM
Nice job Mike. Are those numbers from a non-locking AOD? :eek:

It looks like this fuel pump thing is reaching critical status on numerous member cars.

David Neibert
07-14-2010, 11:51 AM
On my car albeit I have 60#s I have the fuel pressure jacked up to 51 or so But I dont see it being linear either on my car.
An external pump might be the solution but I dont have funds to allow me to experiment. So I need a proven solution. If I can get away without using 80lbs then all the better.


Also Mike do you feel you are running very aggressive tuning down low......I been advised not to run so much spark on a modified vehicle. I know it shows great power numbers but stock spark tables are pretty dangerous for a modified car. So Ive been told.

Ricardo,

The 80# injectors help a lot because they will allow you to lower the base fuel pressure from 51 to 40 psi and that will keep your max pressure down to around 60 psi instead of 71 psi.

With 13.5 volts the 255 high pressure flows 58 gallons per hour at 60 psi and only flows 50 gallons per hour at 70 psi. So just operating at the lower PSI gains 16% in flow.

David

kenewagner
07-14-2010, 11:51 AM
Ken, what kind of issues do you have remaining. I recall an issue with MAF acting up. Is that it? If you are just dealing with little things, and you have the QH installed with a wide band. I'm more than willing to come down for a weekend and help you track down and solve some of this. Heck, if you just need an extra hand, I'll come down and help you out.

The maf just drops the signal during dyno pulls creating an instant lean spike. The pulls were cut short even though HP was climbing. Also had some belt slippage which I beleive I have corrected. It was speculated that there was a feed back from the Snow system due to a not so good ground. I have done a lot of improvement in that area but have no way to see if it is resolved. I should have my lap top back. The original lap top with the QH software took a dive and I have to unregister from that and than reregister to another. Your offer to come down to help me in that area is very much welcome as I am terrible with computers and need someone to instruct me if I am going to join the ranks of the big dogs:D By the way did you get you 400 club gold ring and certificate;):D:D:D

Ken

Mike8675309
07-14-2010, 12:00 PM
Also Mike do you feel you are running very aggressive tuning down low......I been advised not to run so much spark on a modified vehicle. I know it shows great power numbers but stock spark tables are pretty dangerous for a modified car. So Ive been told.

I simply don't have any experience to determine if my spark is aggressive at any point. Perhaps XR7 Dave would have a comment regarding that. To clarify though, My spark below 4000 rpm is still lower than stock. 3 degrees from stock at 2500rpm, and 2 degrees from stock at 3200rpm. with stock commanded at 4000rpm and up.

I assume the main concern with spark at low RPM is excess cylinder pressure. With 91 octane fuel, hitting excess cylinder pressure typically results in detonation that you can hear. With E85, the dyno operator said that it never knocks. Engines will fail due to stress from timing advanced beyond MBT.

Something I keep in mind. I don't have any intention to increase timing below 4000 rpm going forward. My power and torque look just fine below 4000. Any adjustments I do will be on the dyno, or the track, one degree at a time looking for where no improvement is found.

rzimmerl
07-14-2010, 12:57 PM
Nice job Mike. Are those numbers from a non-locking AOD? :eek:

I think this one is a 5 speed?

Mike8675309
07-14-2010, 01:16 PM
had a meeting to go to. yes, 5 speed, late model (94/95) trans currently. Thus of all the things I have to worry about, choosing the right torque converter is not one of them. (yeah!)

Regarding fuel pumps. I have a friend that has a votech blown Lincoln Mark VIII. He has yet to get it fully powered due to an interesting problem. Specifically, the 280lph fuel pump he had installed (from a Lincoln Navigator) was pumping fuel out of the stock baffle in the Lincoln fuel tank FASTER than it was filling up from the small stock doors in it. Thus his fuel pressure would drop as soon as he started hitting around 4500rpm.

He recently pulled the tank (its steel in the Lincolns, btw) and had a local shop gut the stock baffle, and build a new one. Basically building a box in the corner of his fuel tank with a spring loaded flapper door that will let fuel in, but not fuel out.

I don't recall how the baffle is configured in our tank, i.e can it be removed, is it self contained. But if there is such a thing in our tank, that will need to be addressed.

With an external pump, the in tank pump essential ends up acting as a lift pump, ensuring the external pump has sufficient fuel. External pumps tend to be rated about 400% larger in flow for the same pressure and voltage as the internal pumps since their main application is as a booster or use on high horsepower drag cars.

Toms-SC
07-14-2010, 01:19 PM
The issue is, where the heal do you mount it?

rzimmerl
07-14-2010, 01:26 PM
The issue is, where the heal do you mount it?

Somewhere on the frame rail shortly after the fuel tank. They are the same size as the in tank pumps, just require some hose clamp style mounting brackets.

http://www.autoperformanceengineering.com/html/ext_pump.html

Toms-SC
07-14-2010, 02:32 PM
Group buy later this year? :D;)

Ira R.
07-14-2010, 03:19 PM
Ricardo,

The 80# injectors help a lot because they will allow you to lower the base fuel pressure from 51 to 40 psi and that will keep your max pressure down to around 60 psi instead of 71 psi.

With 13.5 volts the 255 high pressure flows 58 gallons per hour at 60 psi and only flows 50 gallons per hour at 70 psi. So just operating at the lower PSI gains 16% in flow.

David

Interesting arithmatic but now I have a question. My base fuel pressure is at 40psi now. I have the 60# injectors and I have been maxing out fuel pressure at 60 psi before it starts to wiggle a little at the top of the run. So I'm not following the logic that the 80# injectors are a better option.

What is it that I am missing?

Ira

ricardoa1
07-14-2010, 03:32 PM
Interesting arithmatic but now I have a question. My base fuel pressure is at 40psi now. I have the 60# injectors and I have been maxing out fuel pressure at 60 psi before it starts to wiggle a little at the top of the run. So I'm not following the logic that the 80# injectors are a better option.

What is it that I am missing?

Ira

Ira Id like some insight on your set up because I dont understand how you are able to maintain pressure and or not run out of injectors...Maybe your pumps is very good pump made on a wednesday and mine was made on Friday....
Do you have any info on your injector duty cycle and other info. Because of your set up is why I am hesitating jumping into 80s. Mind you I will be running nitrous but I dont even have fuel on the 93 octane tune.
Also do you have a pressure gauge in the car to monitor or just in the engine?
I know you can tune around low pressure but the Duty cycle just keeps climbing. And I cant even go past 6000 rpms because it is too dangerous.

David Neibert
07-14-2010, 04:26 PM
Interesting arithmatic but now I have a question. My base fuel pressure is at 40psi now. I have the 60# injectors and I have been maxing out fuel pressure at 60 psi before it starts to wiggle a little at the top of the run. So I'm not following the logic that the 80# injectors are a better option.

What is it that I am missing?

Ira

Ira,

I'm just saying that 80# injectors can deliver more fuel to motor using the same pump, because you are able to operate the pump at a lower pressure where it's more efficient. Larger than stock fuel lines also help to reduce pressure drop between the pump and the fuel rail.

I was able to make about the same amount of power you are now on my 3.8 motor w/1.7 AR using 60# injectors and a 255 hi press pump with base pressure set to 43 psi. Didn't need the boost a pump unless using nitrous.

When I got the new 4.2 motor and started overdriving the blower too much (another 8.3%) to get the boost back up to 20 pounds, is when I started having fuel problems. I think it needed the extra fuel to cover the additional HP consumed by the blower.

David

Ira R.
07-14-2010, 04:48 PM
Ira,

I'm just saying that 80# injectors can deliver more fuel to motor using the same pump, because you are able to operate the pump at a lower pressure where it's more efficient. Larger than stock fuel lines also help to reduce pressure drop between the pump and the fuel rail.

I was able to make about the same amount of power you are now on my 3.8 motor w/1.7 AR using 60# injectors and a 255 hi press pump with base pressure set to 43 psi. Didn't need the boost a pump unless using nitrous.

When I got the new 4.2 motor and started overdriving the blower too much (another 8.3%) to get the boost back up to 20 pounds, is when I started having fuel problems. I think it needed the extra fuel to cover the additional HP consumed by the blower.

David

Okay, I understood that. For some reason I read what you wrote as saying the smaller injectors delivered more fuel but of course that can't be right. I guess what also confused me was thinking that switching to 80# injectors might make a difference but even that wouldn't make up for the lack of fuel pressure, only volume.

Ira

Ira R.
07-14-2010, 04:58 PM
Ira Id like some insight on your set up because I dont understand how you are able to maintain pressure and or not run out of injectors...Maybe your pumps is very good pump made on a wednesday and mine was made on Friday....
Do you have any info on your injector duty cycle and other info. Because of your set up is why I am hesitating jumping into 80s. Mind you I will be running nitrous but I dont even have fuel on the 93 octane tune.
Also do you have a pressure gauge in the car to monitor or just in the engine?
I know you can tune around low pressure but the Duty cycle just keeps climbing. And I cant even go past 6000 rpms because it is too dangerous.

I don't know that I am or am not running out of injectors. I have not logged any info on the injectors but at some point will. Right now the information I have comes from watching a temporarily hooked up fuel pressure gauge that was attached to the engine. It jumped right to 60lbs at full throttle and started to wiggle some on the top end - I didn't really notice at what rpm - but not on every run. But I am sure I too am experiencing the same problem everyone else is now finding with fuel pressure since we are all running pretty much the same setup.

As far as why the difference, who knows. Every fuel pump is different and a difference of .25 volts could make all the difference for all I know.

Once I get to log this data I will be happy to let you know.

Ira

grey500se
07-14-2010, 07:10 PM
Nice numbers OP

255 lph FP is barely enough to support 75 lber's @44psi and 100% duty cycle 44psi for a V6, you may be able to support the 80 lb'ers if you crank it up to 50-51psi base pressure, if your using E85 you need atleast 25% more fuel for its lower heat value, so to achieve 560 chp, 80 lb's is just enough at 85% duty cycle. So you're right on the limit.

OP, what MAF are you using?

Mike8675309
07-14-2010, 10:13 PM
Ken... I talked to the other mike. Work out a couple dates with Mike then check with me and we'll both come down and help you get things straitened out fast. No ring.

Ira... Post up a data log in the tuning forum here. my guess is the injector duty is already in the file, if you load it up into excel look to the right most columns I think you will see it. If you find you are going lean or dave said there is a loss of fueling control at high rpm, and you see a good 60psi that indicates that you are running out of injector and likely have a duty cycle over 100. I see it is the fuel pump because of two things. #1 - with 60lb injectors and gas, I had no problems with tuning the MAFv curve and getting AFR control at 6000rpm before. This based on logs. What that tells me now is that my pump was likely loosing pressure but with gas, my injectors could increase their pulsewidth to make up for the lower pressure.

The switch to E85 has increased my fueling needs by about 22%-30% and brought injector pulse width changes to their limit, causing AFR to raise due to lower fuel pressure. I added the fuel pressure sensor the same time I did the injectors, so I couldn't actually log fuel pressure before now.

If I could crank the fuel pressure up, I would. But it's a stock regulator. Again, the future will be new fuel lines, new fuel rail (or modified stocker) and new regulator. The fuel pump issue itself I'm still not sure on, but something or a combination of things will be done to ensure proper and reliable fuel delivery.

I like my car and I intend to drive it as it is for the rest of the summer and enjoy it. Winter will be here soon enough.

p.s. MAF is C&L 80mm.

decipha
07-14-2010, 10:44 PM
just a little side note

the injectors don't max out until about ~115% duty cycle

fueling recommendations

$100 trickflow 43gph external w/ relay http://www.summitracing.com/parts/TFS-25004/KitComboContents/
$110 3/8" SS fuel lines http://www.summitracing.com/parts/SUM-220238/
$110 mallory afpr http://www.summitracing.com/parts/MAA-4305M/

Mike8675309
07-14-2010, 11:10 PM
just a little side note

the injectors don't max out until about ~115% duty cycle

fueling recommendations

$100 trickflow 43gph external w/ relay http://www.summitracing.com/parts/TFS-25004/KitComboContents/
$110 3/8" SS fuel lines http://www.summitracing.com/parts/SUM-220238/
$110 mallory afpr http://www.summitracing.com/parts/MAA-4305M/

Do you prefer the mallory fpr? I've been planning on the Aeromotive A1000-6 based on info I've found, and it has two inputs, thus I can split my rail. Run a -8 from the tank to a Y, then run -6 from the Y to either side of the rail, then run -6 from the rail into each port on the A1000-6. Then run -6 all the way back to the tank for the return.

Ira R.
07-14-2010, 11:26 PM
Ira... Post up a data log in the tuning forum here. my guess is the injector duty is already in the file, if you load it up into excel look to the right most columns I think you will see it. If you find you are going lean or dave said there is a loss of fueling control at high rpm, and you see a good 60psi that indicates that you are running out of injector and likely have a duty cycle over 100. I see it is the fuel pump because of two things. #1 - with 60lb injectors and gas, I had no problems with tuning the MAFv curve and getting AFR control at 6000rpm before. This based on logs. What that tells me now is that my pump was likely loosing pressure but with gas, my injectors could increase their pulsewidth to make up for the lower pressure.



I don't have a good log to put up so I don't know if this is any help at all but I do have a little piece of one that shows that at about 5100rpm the INJDUTY says 66.8394 with a VBAT of 13.0625 and a few other columns of numbers.

Not much else logged because I messed up and this was like the first run I ever did trying to log anything. All I was doing was getting on the highway so I could kick it a little. But i couldn't stay in it long enough to get anything worth while. I have to actually take the car out and create a log of a few runs before I have any data worth anything I'm sure.

Once I get the LC-1 sensor calibrated I will take it out again and check it out.

Ira

rzimmerl
07-15-2010, 07:03 AM
Do you prefer the mallory fpr? I've been planning on the Aeromotive A1000-6 based on info I've found, and it has two inputs, thus I can split my rail. Run a -8 from the tank to a Y, then run -6 from the Y to either side of the rail, then run -6 from the rail into each port on the A1000-6. Then run -6 all the way back to the tank for the return.

Sounds like a very good plan for the fuel lines. The A1000-6 does have two inlet ports, with a return, I installed one this year based on the good comments of others.

grey500se
07-15-2010, 08:18 AM
Do you prefer the mallory fpr? I've been planning on the Aeromotive A1000-6 based on info I've found, and it has two inputs, thus I can split my rail. Run a -8 from the tank to a Y, then run -6 from the Y to either side of the rail, then run -6 from the rail into each port on the A1000-6. Then run -6 all the way back to the tank for the return.


My route is similar but I wanted to keep the fuel from heating and keep the piping down, so from the tank it would be a -8 AN (if I recall I think a Walbro 255 outlet is 3/8"), then a 3 port splitter, 2 -6AN feeding the fuel rails, the other going to the -6AN FPR then 3/8" return line from the FPR outlet, you can dead end the fuel rails or couple them on the frontside. Your route is fine but your still running all the fuel through the rails before it returns and its more piping. If I did it again, I would never EVER use SS braided lines but socketless hose, I also got rid of all my banjo fittings and replaced them with -6AN 90's, I do have a different engine but banjo's are a no no IMHO.

I'm using a Mallory 4305 0-100psi 1:1, they had problems with it 5 years ago, the pressure would get stuck after 1-2 hrs of driving but they fixed that, no pressure fall off with my 50 lbr's @12psi boost 46psi base pressure with the 2.3L whipple with the setup mentioned above.

Getting back to the note about duty cycle, if you run them too high lets say @ 6000rpm your intake valve may only be open for 18 milliseconds (just a guess, I don't have the formula on me and depending on the cam duration) and your running your injector at 100% (its static anyway at this point) and requires 20 milliseconds of pulses to inject the amount of fuel required, so your not going to get enough fuel, I think its best to run them at a lower duty cycle this will provide more time for atomization of the fuel but I guess thats obvious. Although big injector pulsewidth is too low for idle and your idle and drivability is poor.

Mike8675309
07-15-2010, 11:05 AM
With your suggestion on the rails, I assume you are saying, 2 lines from the tank to the engine compartment. The supply line is split into 3 lines, one to each rail, and then one to the pressure regulator. The rails may or may not be tied into each other (wouldn't hurt as it would help balance pressure). Then the return from the regulator goes back on the next line. Is that a correct read? So then what you are saying is that the Fuel Pressure Regulator will essentially regulate the pressure in all 3 lines (the one to the regulator, and the two to the injector rails)? I am not a plumbing guy, so I just need to confirm. My concern is that the regulator would not be regulating the rails. but I get the feeling my mind isn't wrapped quite around how that works.

Regarding Duty cycle. Yes, we want to keep it reasonably low. I believe most people are happy if at WOT at top RPM, if duty cycle is right around 80%. That allows you to not be over injected, and still gives you room for adaptive to take control and say I need 7% more and actually get 7% more. I think where some of our discussion here is not about the ideal duty cycle, but more the duty cycle you can get away with. As we have seen on bigger motors (at least I've seen them in hot rod, and car craft), eventually you get to the point where a single injector simply can not inject enough fuel fast enough, thus the drag cars that run 2 or 4 injectors per cylinder. I agree on hoses. Unless required by rule, the push lock hose and fittings are highly reliable and much easier to work with. The only down side, is that teflon lined hose is expensive.

A lot of the historical drivability issues with large injectors has been that large injectors were not designed for non-drivability issues. With the drive to more efficient, yet higher horsepower production vehicles, and the growth of late model motors in motorsports (and EFI) we've seen improvements in injector designs. The 80lb injectors I'm running essentially needed no adjustments related to closed loop operations. I took out the 60's. put in the 80's, put into the tune the details on the 80's (slopes, breakpoints). Wrote the tune, and started the car. done.

One thing to point out is that for most engine control systems (other than direct injection systems) the injector is not waiting for the valve to open. The injector actually starts to fire before the valve opens, otherwise it would never be able to get all of the fuel in the cylinder before the valve closes at high RPM. With the Quaterhorse you can actual make adjustments to the injector timing, but that's beyond the scope I intend to play with.

grey500se
07-15-2010, 04:07 PM
It's one feed line from the fuel pump in the tank, if your going to a bigger pump I say atleast 1/2" diameter feed hose, but for my 255 the 3/8" hasn't had any issues, then once the line gets near the engine 3 port split, the rest is as I mentioned. I do have a cross over tube to balance the pressures in both fuel rails.

Can you recommend a brand for injector's I want to upgrade to 75 lb Siemens injectors but don't know how good big injectors are at small PW's, the 50 lb Accel's I have (actually a GM injector I had modified) are great at low PW's I'm running VP100 while I'm tuning but hope to go to GT100 because its $4 cheaper per gallon, GT100 is $12/gallon here. What's your pulse width at idle, mine is under 2.5ms or thereabouts.

Mike8675309
07-15-2010, 07:29 PM
Can you recommend a brand for injector's I want to upgrade to 75 lb Siemens injectors but don't know how good big injectors are at small PW's, the 50 lb Accel's I have (actually a GM injector I had modified) are great at low PW's I'm running VP100 while I'm tuning but hope to go to GT100 because its $4 cheaper per gallon, GT100 is $12/gallon here. What's your pulse width at idle, mine is under 2.5ms or thereabouts.

The Deka/Siemens 80lb injectors that I and others are using are very good at low pulse widths. These are a improved flow version of their 60lb injectors. XR7 Dave may have a set to sell, otherwise you can buy them from www.racetronix.biz.

My pulse width at idle is between 1.38 and 1.47. Idle is about 850rpm. and this is setup for E85. When setup for Gasoline PW was 1.16 to 1.22. I'd have to dig to figure out what the 60lb/hr injectors were. But so far these Deka/Siemens injectors (that's what the 60lb/hr were) have proven to be very reliable. I haven't heard a bad thing about them.

decipha
07-15-2010, 08:16 PM
I like the mallory, I have the same one I posted the link to above
the mallory regulator has 4 equalization ports as well :)

I'm reusing that same regulator that I used for my 351 swap a few years ago I've never had a problem with it, and don't foresee and problems in the near future

the way i had those 4 ports rigged, 2 went to each fuel pump, and the other 2 went to each rail, the less connection the better ;)

You can run the line from the pump to the rail then out the rail to the regulator, it doesn't matter if the rail is before or after since the regulator is just going to bypass any pressure over its threshold to the return port.

you can reduce the injector timing at higher loads to spray the injectors earlier so you get the full charge in, at lower loads you typically want to spray the injectors after the exhaust valve is closed

any injector can be tuned to perform just as you want it to if you know what your doing :p

just as stated those deka 80s are nothing more than a ported 60 so to speak

BLOWN38
07-15-2010, 09:51 PM
Get the 80s... They're GRRREEAATT!!!