i have an 89 l98 with vortec heads edelbrock intake and a 650 cfm carb i want to put a set of afr 190cc heads and an aggressive cam but i dont know how much horsepower the l98 can handle
when it comes down to it my buddy is swapping an 04 cobra motor in his car i.e 4 valve completely built for boost with a blower with 390 horsepower i want to make somewhere around 415 is that safe with the stock bottom end i dont wnat to put out 3 grand then have the motor blow

thanks for all the advice
oh and also if anybody has a better head and cam suggestion open ears

 

If the bottom end is the same as it left the factory in 1989 then I highly suggest you pull it out and inspect it. There is no way any of us could tell you how many miles you have left on your engine. A zero-mile small block chevy bottom end can usually handle 400 horsepower with no problems but there is no telling on a 17 year old engine.

 

I'd say 400-425 would be the highest safe range for a daily driver that you arent too hard on. If you are going to be winding it out all the time at the track and things like that then you might wanna put money aside for a forged bottom end. Things happen...

 

VincentZ28 in our local club is running a tad over 370hp to the rear wheels. With an M5 I would say he is around 435hp at the motor. No problems with the motor. The transmission and rear end cry uncle though.

 

awesome its got about 70 k on it any suggestions about the heads and cam i want a really good combo all roller

 

You'll need to jump up to a higher stall speed eh? What's in it now?
The AFR 190cc eliminators sound great.
Perhaps a xr282hr or something would work nice. Be a bit cammy, but I think that's the idea right?

 

of course thats the right idea i'm trying to switch to a five speed or six speed right now its got a 2300 stall by roller i meant rocker arms and lifters

 

Yea, I figured by roller you meant lifters, and ergo, camshaft.
Are you thinking hydraulic, or are you willing to go..... (drumroll), SOLID?

 

i have solid now its kinda annoying with the clacking and all i'm trying to get my car set up for road racing and i wanna make it as easy as possible for the engine to rev lol

 

I'll let you know after this summer, going to be bolting on a set of AFR 195 eliminators and cam to the stock 42K short block with my blower making 10psi

Should be fun

 

Vincent's engine isnt stock, its been freshened up with new rings and bearings, etc.

Jerry's engine, however, went 11.60 on a 200 nitrous shot once, and several 12 second passes on a 100 shot, and was just fine. It had cam/heads, but a stock bottom end with over 100,000 miles. Other's experiences will vary greatly.

 

my buddy is running 10.60s on a turbo tpi motor with 130k on the engine, just puts in new bearings after every season, uses ARP bolts for rods and mains.

 

Stock pistons?

 

another similar question the stock redline on the l98 is 5500 i have my shift lite set at 54 because the cam suposedly makes power to 5600 but i havent had my car dynoed so i dont know where it stops making power is it safe at where it is

 

yes, the motor has lasted 2 seasons of driving at the track and on nice days and hasn't blown up yet but he's waiting for it.

 

The cam makes power to that level, but the stock TPI intake will start to fall off at 4600 rpms or so. With my ported stock one it made peak power at 4800 rpms and now with the modified aftermarket it goes to 5200 but holds until 5800. You should be able to feel with the butt-dyno when the car stops pulling. Shift there. It should be somewhere in the 5000-5200 range, and you'll be fine there.

 

Impressive! hopefully mine will do the same lol. Does you buddy post on this forum?

 

no he doesn't but if you have any questions let me know, since I see him 2-3 times a week, typically he's under the hood of my car or one of his shop's cars.

 

Maybe ask you buddy what year of car did he get the engine from and a complete run down of his spec's like cam, heads, intake, boost PSI, piston rings, what he is using for engine control stuff like that. He has a very intresting build and great times on such a old engine.

 

its not tpi anymore its carborated with a performer intake and a 600cfm carb

 

well if it's a performer intake and 600 cfm carb you don't have to worry about breaking anything unless you rev it to the moon
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motor is a roller block, cam is comp cams custom grind, heads are L98s with a little porting, intake is a tpi some aftermarket parts, rings are stock, engine control is whatever those guys on the DIY prom board use for 16psi. motor still has good compression, so I wouldn't call it "old"

 

3,042 hp... just make sure to keep it under 3,500 RPM.

 

hope your not doing that with stock heads. my friends 91 stock L98 blew up doing that. he was sort of stupid, and so against my judgement we took it to my friends tranny shop and got the 700r4's shift point moved to 5500 rpm or something stupid like that. he thought it would be great and more power, but 4 passes down the road, the engine blew, and so did the tranny. and now its a cube.

 

How does your rambling in any way signify that the heads were the causal problem as opposed to say the springs or maybe the rockers or perhaps the pushrods or maybe even user error (wholly ignoring everything else in that conglomeration of moving objects known as the engine)? I find your position wholly untenable as presented and spreading the Vatozone know-how does nothing to help the community at large.

Oh yea, IIRC Kevin was doing that on stock heads, but he knows how to put things together properly. I don't readily recall what he's currently running.

 

Damn even stock rings to with 16psi, I would never guessed that. Now I don't feel so scared with the head install and extra load on the engine that it will get, especially if you say your buddy has been running like that on the street and the car gets regular track use. Thanks for sharing.

 

as long as there's no detonation you'll be fine, to a point, some people just get lucky on motors.