how much can a l98 handle
#1
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Car: 1986 Z28
Engine: L98 Block Vortec Heads Comp Xtreme
Transmission: Built 700R4
Axle/Gears: 10 bolt with Auburn 3.73 posi unit
how much can a l98 handle
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
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
#2
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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.
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Car: 1990 IROCZ Camaro
Engine: 350 4bbl, 200cc Heads, 270hr Cam
Transmission: 700R4 w/ Trans-Go shift kit.
Axle/Gears: GM 10 bolt Posi
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...
#5
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Car: 1986 Z28
Engine: L98 Block Vortec Heads Comp Xtreme
Transmission: Built 700R4
Axle/Gears: 10 bolt with Auburn 3.73 posi unit
awesome its got about 70 k on it any suggestions about the heads and cam i want a really good combo all roller
#6
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Car: 1982 Trans-Am
Engine: 355 w/ ported 416s
Transmission: T10, hurst shifter
Axle/Gears: 10 bolt, true-trac, 3.73
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?
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?
#7
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Car: 1986 Z28
Engine: L98 Block Vortec Heads Comp Xtreme
Transmission: Built 700R4
Axle/Gears: 10 bolt with Auburn 3.73 posi unit
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
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#8
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Car: 1982 Trans-Am
Engine: 355 w/ ported 416s
Transmission: T10, hurst shifter
Axle/Gears: 10 bolt, true-trac, 3.73
Yea, I figured by roller you meant lifters, and ergo, camshaft.
Are you thinking hydraulic, or are you willing to go..... (drumroll), SOLID?
Are you thinking hydraulic, or are you willing to go..... (drumroll), SOLID?
#9
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Car: 1986 Z28
Engine: L98 Block Vortec Heads Comp Xtreme
Transmission: Built 700R4
Axle/Gears: 10 bolt with Auburn 3.73 posi unit
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
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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.
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Car: 1986 Z28
Engine: L98 Block Vortec Heads Comp Xtreme
Transmission: Built 700R4
Axle/Gears: 10 bolt with Auburn 3.73 posi unit
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
#16
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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.
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Car: 89 GTA
Engine: 5.7L Supercharged
Transmission: T-56
Axle/Gears: Moser 9" 3.70
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.
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Car: 1986 Z28
Engine: L98 Block Vortec Heads Comp Xtreme
Transmission: Built 700R4
Axle/Gears: 10 bolt with Auburn 3.73 posi unit
its not tpi anymore its carborated with a performer intake and a 600cfm carb
#21
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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"
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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.
Last edited by xpndbl3; 12-21-2006 at 04:14 PM. Reason: Automerged Doublepost
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Car: 92 trans am/ 93 dodge spirit V6
Engine: L98 V8 - 350
Transmission: TH-700-R4
Axle/Gears: 3.23
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.
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Car: Tree Huggers
Engine: Do Not
Transmission: Appreciate Me.
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.
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.
#25
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Car: 89 GTA
Engine: 5.7L Supercharged
Transmission: T-56
Axle/Gears: Moser 9" 3.70
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"
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