L98 Rebuild ?
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Joined: Jul 2002
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From: Bellevue NE
L98 Rebuild ?
I have Finally decided to just rebuild my L98. I am happy with the stock motor, Would like to keep car original. The motor currently has 90k miles on it and with a good tune has plenty of power, Vette is still way quicker than my 95 mustang gt. I have a couple of ?'s about my rebuild and would like to know if I can Replace my stock cast crank with a Scat 9000 nodular iron crank, stock rods for Lt1 rods and would these things make the bottom end of my motor stronger. How much more horsepower can the motor make in the form of a 355? Sorry this is so long, Thanks :chevy :flag
Melting Slicks
Joined: Feb 1999
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Re: L98 Rebuild ? (91L98Vette)
My friend, I have a tuned port 355 that I only spent 3 grand on rebuilding, and it keeps up with LS1 Corvettes. In a Camaro no-less (heaven forbid).
Yes, you can swap cranks. I don't think you need to though, because the L98 is a low-rpm motor for one thing, and you won't be making enough horsepower to destroy your stock crank, for another.
So save your money to spend on a better cam and exhaust. Those are two areas that have helped me the most.
Yes, you can swap cranks. I don't think you need to though, because the L98 is a low-rpm motor for one thing, and you won't be making enough horsepower to destroy your stock crank, for another.
So save your money to spend on a better cam and exhaust. Those are two areas that have helped me the most.
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Joined: Feb 2000
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From: Texas
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St. Jude Donor '03 thru '10, '17
Re: L98 Rebuild ? (MoMo)
Momo, so, what's that L98 Camaro run in the 1/4? What year is it? I had an '86 IROC A4 and then a '91 Z-28 w/ the 5 speed and dual catalyst exhaust and 3.42 posi. Those were great cars, extremely under-rated by the car magazines. The '91 would do 140+ mph (closed course, professional driver, of course).
91L98, why would you want to rebuild a motor w/ only 90K on it? If you do, you ought to check w/ TPIS. They make some great cams (and other goodies) developed just for the L98. Also, your connecting rods are good as is for the same reason Momo mentioned (rpm).
[Modified by need-for-speed, 10:10 PM 10/18/2002]
91L98, why would you want to rebuild a motor w/ only 90K on it? If you do, you ought to check w/ TPIS. They make some great cams (and other goodies) developed just for the L98. Also, your connecting rods are good as is for the same reason Momo mentioned (rpm).
[Modified by need-for-speed, 10:10 PM 10/18/2002]
Melting Slicks
Joined: Feb 1999
Posts: 3,078
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Re: L98 Rebuild ? (need-for-speed)
I haven't run it in the quarter yet. I am at high altitude, and Bandemere is at 5,800 ft ASL. So times up here are at least a second off the times at lower altitudes. As a measuring stick, LS1 Camaros frequently run at Bandemere and average low to mid 15 second runs at 95 to 97 mph. I realize this is a lot slower than you guys probably see down lower, but it's a direct result of the altitude difference.
To compare, I had this very engine in my 1968 Corvette convertible, with a Muncie M21 transmission and 3.36 rear gears on street tires (27"). With a Holley 750 and a dual plane, I was running a 14.9 second quarter at 101.2 mph. Which would actually slightly nose out an LS1 F-body.
In the IROC with a tuned port, steeper tranny gears and a 3.23 rear end, I have a lot more low and midrange punch than I had in the Vette. I expect at the very worst that I'm running around mid-14's. I would guess 14.5 @ 103.
At lower altitude, it's probably a solid 13-second performer. But that's not tested.
To compare, I had this very engine in my 1968 Corvette convertible, with a Muncie M21 transmission and 3.36 rear gears on street tires (27"). With a Holley 750 and a dual plane, I was running a 14.9 second quarter at 101.2 mph. Which would actually slightly nose out an LS1 F-body.
In the IROC with a tuned port, steeper tranny gears and a 3.23 rear end, I have a lot more low and midrange punch than I had in the Vette. I expect at the very worst that I'm running around mid-14's. I would guess 14.5 @ 103.
At lower altitude, it's probably a solid 13-second performer. But that's not tested.
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Re: L98 Rebuild ? (MoMo)
MoMo,
I didn't notice you lived in Morrison. We almost moved to Lakewood 4 years ago. My employers (KN Energy/ Kinder Morgan) corporate offices are there. Very nice place (other than the thin air/ HP killer). It's funny, one of the reasons I chose to move back to the Houston area (in addition to housing costs and the type of job I prefer) was the altitudes affect on my favorite hobby-HP. When people at work ask me why I chose SE Texas over Lakewood, CO , I only tell them the first 2 reasons, they'd think I was nuts if I told them the 3rd reason. I do agree that altitude is a big perofrmance killer. When I moved from Hobbs, NM (4000 ft) to Searcy, AR (400 ft), my 91 Z-28 felt like it gained 75 HP.
Is your 427 mentioned in your sig a small block or rat? Of couse, 10 years ago that would sound like a stupid question but they are coming up w/ all sorts of SBC combos these days.
I didn't notice you lived in Morrison. We almost moved to Lakewood 4 years ago. My employers (KN Energy/ Kinder Morgan) corporate offices are there. Very nice place (other than the thin air/ HP killer). It's funny, one of the reasons I chose to move back to the Houston area (in addition to housing costs and the type of job I prefer) was the altitudes affect on my favorite hobby-HP. When people at work ask me why I chose SE Texas over Lakewood, CO , I only tell them the first 2 reasons, they'd think I was nuts if I told them the 3rd reason. I do agree that altitude is a big perofrmance killer. When I moved from Hobbs, NM (4000 ft) to Searcy, AR (400 ft), my 91 Z-28 felt like it gained 75 HP.
Is your 427 mentioned in your sig a small block or rat? Of couse, 10 years ago that would sound like a stupid question but they are coming up w/ all sorts of SBC combos these days.
Melting Slicks
Joined: Feb 1999
Posts: 3,078
Likes: 1
Re: L98 Rebuild ? (need-for-speed)
It's a rat motor, and it's in. I just haven't updated my sig yet. I've gone all out on this engine and it shows. Everything is show quality. Very nicely spit and polished. I'm waiting on a pulley from March, and in the meantime, I'm wrapping everything else up.
You probably made a wise choice avoiding Colorado. The economy here is incredibly bad right now, and the cost of living is unbelievably high.
Groceries, by comparison, make buying stuff for the hotrods seem almost cheap.
The altitude has had the effect of making me build cars stronger for up-here driving, and then when I take them down lower, I am amazed at the power increases. I wish I lived at a lower altitude for that reason.
You probably made a wise choice avoiding Colorado. The economy here is incredibly bad right now, and the cost of living is unbelievably high.
Groceries, by comparison, make buying stuff for the hotrods seem almost cheap.
The altitude has had the effect of making me build cars stronger for up-here driving, and then when I take them down lower, I am amazed at the power increases. I wish I lived at a lower altitude for that reason.
