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90coug
05-12-2009, 05:44 PM
I've done some searching but didn't get any results that I was happy with.

What is the max HP and Torque a stock 95 SC bottom end will handle?

Toms-SC
05-12-2009, 05:51 PM
Just had this conversation about a month ago. Nobody will agree to a magic horsepower number but what I have been able to gather is that they can hold up to abuse BUT detonation is the killer for them. :cool: It matters how much abuse your short block has had too, did the gaskets pop before you changed em? Oil done regularly?

superdadsc
05-12-2009, 05:59 PM
About as much money as you can throw at them if you have the supporting fuel requierments and a proper tune!:eek:

Stephen

90coug
05-12-2009, 06:44 PM
Yea there doesn't seem to be a set answer for this one. Oil has been changed regulary (that I know of) and no blown head gaskets.


Well what the heck, I'll throw it all together and see what it can do :)

thunderkid84
05-12-2009, 08:10 PM
i know a member that has hit around 450 rwhp

sinhumane
05-12-2009, 08:30 PM
ar guys are running around with 400+ hp tuned reliably on stock motors. its easy to fathom 450+ on a stock internals wiht proper tuning. hell, superred91 is making damn near that with his gt35r setup, jsut a rebuilt stock motor.

superdadsc
05-12-2009, 10:09 PM
If the money presents itself, throw all the parts you need and want to set her up the way you want on the stock short block.

Once it is together and dialed in she should hold for Xamount of time. During that time period buy another block and build a rock solid forged bottom end so if and when the stock one blows you can pull it out and throw in the new one.

No down time. Every SC'r should have a backup forged block sitting on deck waiting to get in the game!

That was my plan when I bought my motor and pulled my original 95 engine out. I was going to build it just so, take a year or whatever and when the other one died I would be ready to go!

Just think about it, you could just beat the crap out of it because you had another waiting in the wing!:eek::eek::D

Stephen

XR7 Dave
05-12-2009, 10:28 PM
We made 475rwhp and if we'd have used race fuel it would probably still be together today. I think done correctly the stock bottom end might hold together at over 500rwhp but the key is "correctly." Chances that you'll do it correctly are about 100:1, maybe less.

For most people 350rwhp is plenty and for some 250rwhp is more than enough to trash the bottom end.

90coug
05-13-2009, 11:44 AM
super secret update

kenewagner
05-13-2009, 12:33 PM
Cam - 224 intake duration, 230 exh duration .550 lift
Ported heads with bigger valves, valve size slips my memory
MPX blower with 10% and coated rotors + raised top
85MM TB
76MM MAF C&L
42lb Injectors – Think I should go bigger? What’s everyone’s experience?
255 liter fuel pump - Should I upgrade the fuel line, everyone I've seen get's pinched right there under the car coming up from the fuel filter, junk plastic lines.
Fresh air intake
Front mount IC, maybe a double haven’t figured that one out yet
Aluminum drive shaft
Aluminum flywheel
Performance clutch
3:55 rear
Tune

Think some better roller rockers would be worth it?

Maf should be replaced to match the TB
42lb injectors wont do it
Fuel lines and rail will be enough
More overdrive on the blower


Ken

90blkbrd
05-13-2009, 01:18 PM
You didn't state what you are running for exhaust, but I don't think the 42's will be enough.

I can't imagine my car with 3.55's. :eek:

What rocker ratio was listed for those cam specs?

IMO that is a really big cam for a 5-speed car.

Get a 85 mm C&L tuner MAF

thunderkid84
05-13-2009, 08:15 PM
-3.27 gears at most
-60# injectors
-overdrive the mpx about 25% and dont bother with the coated rotors.

90coug
05-13-2009, 09:03 PM
I'm working with what I have. The rear gears are already there so they won't come out until I'm fed up with the results. The coated rotors are already there along with the MPX and 10%. However I do think some bigger injectors and the correct MAF are in order. The exhaust will be custom, and no plans for headers, will try and port the stockers. I pulled the engine out of the car a bit prematurely; I won't have the goodies ready for a month or so. At least it's staring me in the face every time I head out to the garage. Thanks for the input fellas.

-B

pablon2
05-14-2009, 08:53 AM
I'm working with what I have. The rear gears are already there so they won't come out until I'm fed up with the results. The coated rotors are already there along with the MPX and 10%. However I do think some bigger injectors and the correct MAF are in order. The exhaust will be custom, and no plans for headers, will try and port the stockers. I pulled the engine out of the car a bit prematurely; I won't have the goodies ready for a month or so. At least it's staring me in the face every time I head out to the garage. Thanks for the input fellas.

-B

At some point you'll want/need to bump up the OD on that MPx. Do yourself a favor and swap the coated rotor pack out now while it is off the car. At the risk of sounding condescending, just b/c something is already set-up to run a ceratin way (coated rotors) doesn't mean it should be run that way.

90blkbrd
05-14-2009, 09:38 AM
At some point you'll want/need to bump up the OD on that MPx. Do yourself a favor and swap the coated rotor pack out now while it is off the car. At the risk of sounding condescending, just b/c something is already set-up to run a ceratin way (coated rotors) doesn't mean it should be run that way.

There's no reason why he can't run 15% od and coated rotors. I think that setup would be ideal for me.

But once you decide to up the OD above 15% you SHOULD replace the coated with uncoated or just let the coating peel off and let it plug the IC and possibly get eaten by the engine.

pablon2
05-14-2009, 09:47 AM
There's no reason why he can't run 15% od and coated rotors. I think that setup would be ideal for me.

But once you decide to up the OD above 15% you SHOULD replace the coated with uncoated or just let the coating peel off and let it plug the IC and possibly get eaten by the engine.

The MPx was engineered to run best at 25%+ OD. In my opinion, if you don't plan to run an MPx at 25% then save yourself some money and get an MPII or ported late model. Of course nothing is easy, running the MPx as many know requires supporting mods. One simply should not throw on an MPx to a basically stock set-up. I will be running mine at 30%, but my setup is about as far from stock as one can get with the exception of the few bigger dogs out there.

My apologies for thread crashing '90coug'.

XR7 Dave
05-14-2009, 10:21 AM
On a mildly modified motor the MPX runs great with 10% OD. I don't believe anyone posting here has ever tested the blower both ways. I have. I've also run the blower at both 15 and 25% OD. 25% OD is generally excessive for most street cars, particularly mild ones.

90coug
05-14-2009, 06:54 PM
Okay some good info here. So I understand that a lot of OD will eventually make the coating come off however until I get to that point I will leave it. I had the MPX with 10% running on a stock motor and it was impressive. My question is how much gain will I see from going to 15-25% OD from the 10%? Are we talking big numbers or just a tiny burst?