bluegrassz

iTrader: (3)

What would you guys say the max hp would be on a stock 92 L98 bottom end?

Suppose you put heads, carb, intake, cam, lifters, timing chain, roller rockers and left the stock bore, crank, rods, and pistons.

The motor has less than 50000 miles on it. I would like to see how much I could get with the stock rotating assembly. Would it rev to 6500 or would that be too much for it?

Sitting Bull

A couple months ago, Hot Rod had a feature about an L98 powered Formula that the guy had doing 10s in the quarter--with a stock shortblock. Look it up.

bluegrassz

iTrader: (3)

thanks, I will check it out.

Anyone else have any knowledge or experience with this?

CHRISMAN2000

iTrader: (1)

I believe it's 400HP

Sitting Bull

No, it has to be a lot more than that for a guy to be running 10s.

F-BIRD'88

There is no particular horsepower level where any more puts
you in the danger zone.

But there are certain things that need to be "managed"
to ensure a reasonable engine life.
One sure killer is detonation. This is the cause of most engine
problems from head gasket failure to rod bearing trouble.
You need to avoid this condition at all cost.
Actually this is true for any motor wether stock or a race motor
with all the best parts. Detonation will turn it into a pile of junk in $econd$.
Run the octane fuel that the motor needs. Run just enough igniton timing to get the job done and no more.
Build the motor to run the fuel you can get at the pump.
Another area where you're going to run into $ trouble$ is exessive rpm. A motor that breaths good does not need real high rpm to make power. Most inexperienced people are under the false impression that rpm=power and more rpm will make you go faster. On a good street motor you need to target making power gains (mods) in the 3000 to 6000rpm range and drive th car to
use this range. Beyond this and the hp/$$$ gains deminish rapidly.
Think good head induction/ exhaust flow and moderate cam timing and you'll be way ahead of the game.

Plan on less than 6500 rpm. A good rev limiter like a MSD is a good investment.
Nothing will tear up a valvetrain faster than over reving it.
Valve float is a killer. Make sure your cam and valve train is up to your rpm target.
The difference between a stock motor and a forged internals motor is its "tuning mistake tolerance" Meaning the forged components will tolerate a little more detonation/ over- rpm before failure. But even these stronger parts will fail too if you get carried away or ignore the warning signs of distress.

All this being said, you can build a real healthy motor by upgradeing the top end on a stock short block.
Just remember, cheap gas is for cleaning parts and rpm costs $$$.

87transam5.7tpi

a stock L98 can handle a decent amount. like said above there isn't a "set" limit to the amount of hp you can have. I've seen a $15,000 motor blow on the first used. so you may be able to do everything ot one stock L98 and rev to 7000rpm+ and then do headers or something on another and blow it at 6000. there is alot more that limits motors than HP

badgta

iTrader: (4)

this is a tough one..........

i have the book on the 10 second firbird......... he has 5000 time slips on a stock l98 bottom end with corvette heads by slp and their biggest l98 cam... he also has superram......

no more than 420 hp i wouldn't think on the motor.... and then he has 125hp n20.........

the main thing was the suspension they talked about...... all the little things with koni ajd's and air bags in the rear... hell i think he has stock springs!!!

i have twice the motor and 150hp shot, my motor better get 10's or i'm selling it......

thats another thing..... i put 150hp shot on mine in the fall and in april the following year after only like 5 runs my no1 rod bearing gave up...... i always run 93 with stock timing at 33* at 3000......... kinda makes ya wonder huh????

i babbied the **** outa mine unless i was racing it....... and even then i left it in drive and the tranny done the shifting where it wanted......

and you know unless you get a damn expensive rod for stroker motors you will go through the same **** i did on the 383 you was thinking of.....

it goes on, and on.............. i'm like the dudes above.... put all the stuff on your 350 ya have and dial it in........ i gaurentee you will be glad you did!!!!

bluegrassz

iTrader: (3)

I guess I should have made the question "RPM limit on stock L98 bottom end"

I was just playing around with dd2000 and checking out the components I wanted to use. The intake I have pulls from 2000-6500. My peak hp was at 6500. I was just trying to find out if the stock L98 bottom end would peter out before the motor reached its peak.

I may just try doing this to see what I can get out of the setup with the stock bore, pistons, rods, and crank.

What about the comp xe282hr cam? Do you think I will have any clearance or valve train problems with it in the stock L98?

CHRISMAN2000

iTrader: (1)

I remember reading that article about the 10 sec firebird. Did he have the engine balanced and blue printed? I also remember him always blowing trannys. Didn't he have some crazy rear suspension made up for the think or something?

bluegrassz

iTrader: (3)

I dont know about the 10 sec formula. I cannot find anything on it. I do remember reading about it.

I would just like to know if the stock L98 bottom end will speed to 6000-6500 RPM safely without destroying the motor. Of course it is not any good for the tpi system, but I will be going carb with larger runner heads and 2.05-1.60 valves.