hi there,

i'm planning to get superchrger with aprox. 6-8psi of boost on my engine, question is will i need to change any thing on my L-98 , here is sprec. of it:

383 stroker w/cast iron crank, Forged 5140 steel rods (I-beam) and Hypereutectic aluminum pistons

cam shaft:
Advertised Duration: 276 int./281 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.503 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.510 in.
Lobe Separation (degrees): 112

Edelbrock heads 165/60cc

HSR

30 lbs injectors (ford racing)

255 walbro fuel-pump

best regards

 

uh hyper pistons have a very bad reputation for problems w. boost, forged would be better, as would a forged crank

 

forged crank for 6-8 psi boost

best regards

 

we have ppl here in cali running 6-8 lbs on completley stock 350's, with no problems, just watch for detonation, Run good gass, and retard the timing a bit.

 

personally I dont think there would be a problem with even running 10lbs of boost. Im running a 150 shot on my car right now and have no problems with detonation.....375hp is 375 hp regardless of how its produced

 

Well, not quite. I would just run forged pistons. The rest sounds fine. There won't be any reason to spin that motor over 6000 rpms.

 

engine will be spin only to 5800 due to cam spec.

best regards

 

Hp = (inj flow rate) x (# of injectors) x (duty cycle) / BSFC

Hp = [30lbs] x 6.4 /.6.... (your 30lb'ers, V8 with 80% duty)(.6 supercharger)

320 horsey's..... I would say you want more!!!!!

I think you need more right now. and your fuel pump is going to be maxed out.

***as a lil rule of thumb for every pound of boost added (without heating the air) is worth 6% more power....***

you should be making around 400-440 hp, (at the motor) with what you listed. 6lbs x 6% is worth 144-158 extra hp. 8lbs = 198-211hp.
So 550-660hp at the flywheel... so 60lb injectors would me a good Idea

I am assuming because your posting on this board you have DIY prom stuff or other efi tuning methods...

ostrich by www.Moates.net.... and www.code59.org is what I use


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WASyl, I've never run hyperneuitc (whatever they're called) pistons but I've been told not to use them with a blower setup. I'd do a search to try and find some real answers as to why not. IF you're buying a 6-8 lb kit you can get buy with the injectors you have IF you run a FMU. If you don't run an FMU then you're going to HAVE to get larger injectors (60#'ers would certainly do it) and retune your ecm.

The big question I have is with those 60cc heads, what compression are you currently running that engine with?

 

just to save you a search....lol.... Hyper pistons or sort of a harder but cheaper material that results in a pretty brittle piston, (the easiest way to put it) great for everything except DETONATION.... where hyper's usuallly crack or bust off a ring landing.

my opinion on FMU's is that they are a band-aid. and from the looks of your list you don't mind tuning.

Plus your 255lph fuel pump becomes pretty weak at 80-90psi

and all this on a cast crank...ouch....

I am wondering the same as AC 60cc, guessing over 10.1 compression

keep the boost under 6 and I would never go over 5500 rpm (EVER), you can get away with quite a bit if you don't spin it to the moon.

E85 would be a good Idea, great for Detonation

maybe saving your hyper pistons and the poor Crank

Non of this is really that bad, your should be able to smash 12's and probably deep 11's for a good long while if you tune that puppy well.

if you want more, your going to need a forged crank, forged pistons, probably every driveline part that is on the car.

 

This is true, but would mean he absolutely will need and upgraded fuel system to handle the extra fuel needed when running E85.

 

As funPain said, I offered the FMU IF you were not going to do any tuning. If you're not going to use the FMU you HAVE to tune otherwise...goodbye pistons and probably goodbye engine when it hits high boost and runs lean.

Long story short answer from me, based on your original question and the details you've provided thus far. I'd change the pistons, drop the compression below 9.5:1, and run an FMU. Else you're on the hairy edge of things. You can go "all out" and drop in larger injectors and jump into tuning.

 

Actually I've heard that hyper pistons are just as strong as forged, but hypers dont move the heat like forged. So the very top of the piston gets super hot under detonation and breaks.

If you were to keep boost between 6 and 8, and tuned the motor well, and I mean well, you'd be fine.

Its really all up to you and the tune.

An FMU will get you close, but not right.

Oh, and yep, you'll need bigger injectors, and a second pump, or a boost-a-pump.

 

oh and whatever you deside, just go ahead and get something like the PLX wideband (I like it) with gauge. so you can atleast see whats going on... it is 250 bucks (www.moates.net)... this is a best tool, engine saver, that you could buy....

another thing that I think you should be running right now.

Question???

What is your goal? This could make our answers more exact, maybe.

 

Well he really should be running a good computer with a wideband anyway.