Engine Rebuild
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,213
Likes: 2
From: Cincinnati oh
Engine Rebuild
My 1985 l98 has about 120k on it, its using about 1.5 quarts of oil between oil changes and starting to use antifreeze. (none in the oil)
I WANT MORE POWER (duh)
I am going to pull the trigger on a rebuild I am looking for about 370hp and 350-400ftlbs of torque (i am using a carb not the TPI.) Open pipes on the stock shorty headers. I dont want to go to radical because i dont want to chnage the 700r, or the rear end.
It is a sunny day DD with occasional runs at Auto cross, drag strip, and top speed. (basically a tire shreader)
I am looking for a good engine rebuild shop preferabale in the Cincinnati Aera.
I also am considering a Crate Engine. Any sugestions on that end would be appreciated.
I am looking to spend in the 3500-5500 range total
Please let me know. I only want to do this once and RELIALIBILTY is the key word here
I WANT MORE POWER (duh)
I am going to pull the trigger on a rebuild I am looking for about 370hp and 350-400ftlbs of torque (i am using a carb not the TPI.) Open pipes on the stock shorty headers. I dont want to go to radical because i dont want to chnage the 700r, or the rear end.
It is a sunny day DD with occasional runs at Auto cross, drag strip, and top speed. (basically a tire shreader)
I am looking for a good engine rebuild shop preferabale in the Cincinnati Aera.
I also am considering a Crate Engine. Any sugestions on that end would be appreciated.
I am looking to spend in the 3500-5500 range total
Please let me know. I only want to do this once and RELIALIBILTY is the key word here
Race Director
Joined: Dec 2000
Posts: 17,551
Likes: 26
From: El Paso Texas
Race Director
Joined: Dec 2000
Posts: 17,551
Likes: 26
From: El Paso Texas
Melting Slicks
Joined: Dec 2009
Posts: 2,236
Likes: 286
They have really good deals on stroker kits for SBCs, the extra displacement will help you get to your hp goal.
I'd even start rebuilding an engine that came equipped w/ a roller cam, live a vortec 350, the cam parts are much cheaper then to retrofit an older engine to a roller cam. Do some research on the troubles that guys been having w/ flat tappet cams w/ todays oils.
I'd even start rebuilding an engine that came equipped w/ a roller cam, live a vortec 350, the cam parts are much cheaper then to retrofit an older engine to a roller cam. Do some research on the troubles that guys been having w/ flat tappet cams w/ todays oils.
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
Remember...
those HP numbers are only FlyWheel numbers. Deduct about 20%..then you have RWHP.
370 FW comes down to about stock power (290) once the math is done and you enter the real world with gravity and drag..
To shoot for 350 at the wheels...means going for 500 at the crank and that is do-able..its just gonna cost more than 5K.
those HP numbers are only FlyWheel numbers. Deduct about 20%..then you have RWHP.
370 FW comes down to about stock power (290) once the math is done and you enter the real world with gravity and drag..
To shoot for 350 at the wheels...means going for 500 at the crank and that is do-able..its just gonna cost more than 5K.
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Le Mans Master
Joined: Oct 2008
Posts: 9,758
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From: Houston Texas
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
"About stock power" (to put this in perspective) is 230 at the crank for a good running '85. At the wheels, it's about 200. 200RWHP
290 RWHP.Also, you need 500 CHP to get 350 at the wheels??? NO. Ya don't. 505chp C6 Z06's put down 440 to the wheels all day long, every day. To get 350 at the wheel requires about 400 chp. In fact, my own box-stock LS2 C6 (400 chp) put down 360 to the wheels.
You'll have to tell us how "real world gravity" affects chp. This should be good...
BTW, OP never said 370 RWHP.
Last edited by Tom400CFI; Nov 28, 2012 at 04:08 PM.
Race Director
Joined: Nov 2003
Posts: 12,221
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
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355, either ported/new heads with cam and ported manifolds is about "right" to push limits of stock stuff. Roller cam gets much better longevity and a bit more power...if you're really looking for reliability in today's world. There are still SOME zinc-additive oils but a roller cam is just easier on the valve train...and cam.
IIRC, you're talking about a $750 bump in overall cost. Like the difference between ported/aftermarket heads, it comes down to what you're willing to pay for. This sounds like a budget scenario that best left with a bolt-on rebuild.
I think a 383 is a option too...but has to accelerate the life of (what remains for0 your trans/diff combo.
I started with the same goal/philosophy 4 yrs ago. Wanted to spend $2500. My finished result ended up triple that and I wish I'd have spent another grand...for what I'd have gotten.
To do this stuff "right", you need resources and time. OTOH, you can still "freshen" up what you have, bolt on a couple of things and accept what that gives. (I'm going to assume you were talking about FW numbers because of this.)
Race Director
Joined: Sep 2003
Posts: 16,838
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From: Database Error Indiana
A ZZ4 should get that, with a carb. I have a ZZ4 shortblock. 180cc aftermarket heads and a Miniram. 12.80 @ 110 is probably at least 350 crank hp. It has a Dana 36 with 3.07 gears and it will smoke the tires real easy on the street.
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,213
Likes: 2
From: Cincinnati oh
good advice I looked into a top end kit from elderbrock http://www.summitracing.com/parts/edl-2097
but figured i should do the bottom end also, and boom Im over 4 grand. I can get a new Vortec 350 for 3447.00 with free shipping
http://high-performance-engines.com/...duct_Code=HP32
I think this will get me down the road, I am wondering how hard it will be to put this in myself. Not sure how hard it will be.
but figured i should do the bottom end also, and boom Im over 4 grand. I can get a new Vortec 350 for 3447.00 with free shipping
http://high-performance-engines.com/...duct_Code=HP32
I think this will get me down the road, I am wondering how hard it will be to put this in myself. Not sure how hard it will be.
Le Mans Master
Joined: May 2006
Posts: 7,708
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From: indy indiana
in the old days ( I am 62), the common thought was that putting a "new" top end and leaving the bottom end alone..would soon lead to bottom end problems..like wearing out your rings much, much faster. If this still holds true, I have no idea.
Team Owner
Joined: Oct 2004
Posts: 81,241
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From: altered state
St. Jude Donor '05
Ive put new top ends on old bottom ends and never had an issue
When people have failiures imo its from improper assy or twisting the pee out of an old bottom end to enjoy that new found power that finally does the bottom end in.
Sham Id go with a GM crate long long before Id ever trust some unknown co or ebay piece. At least you know what youre getting and its all NEW.
When people have failiures imo its from improper assy or twisting the pee out of an old bottom end to enjoy that new found power that finally does the bottom end in.
Sham Id go with a GM crate long long before Id ever trust some unknown co or ebay piece. At least you know what youre getting and its all NEW.
Le Mans Master
Joined: Oct 2008
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From: Houston Texas
Race Director
Joined: Nov 2003
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From: Overland Park Kansas
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I think it's still true -- if you make significant changes to compression. From someone I know -- who works at a speedshop, that's the issue he's seen over the years.
If you change compression, it's more likely to fail early (say bump from 9:1 to 10:1. But, though it can/does develop more cylinder pressure, adding better flowing heads (with more cam lift) doesn't usually cause much issue.
Seems a bump in compression has more effect on rings/how they were broken in.
OTOH, if I had the money to mod an engine, I wouldn't do JUST a top-end to a 100k mile motor. Either you have the money to spend on mods -- and do it the right/complete way -- or you probably shouldn't spend money on it.
Considering shamdave is talking new motor, this doesn't seem to be an issue.
If you change compression, it's more likely to fail early (say bump from 9:1 to 10:1. But, though it can/does develop more cylinder pressure, adding better flowing heads (with more cam lift) doesn't usually cause much issue.
Seems a bump in compression has more effect on rings/how they were broken in.
OTOH, if I had the money to mod an engine, I wouldn't do JUST a top-end to a 100k mile motor. Either you have the money to spend on mods -- and do it the right/complete way -- or you probably shouldn't spend money on it.
Considering shamdave is talking new motor, this doesn't seem to be an issue.
Le Mans Master
Joined: Dec 2006
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From: H-Town Texas
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
Great foundation if you really want to keep building though. LS7 would be nice!
Le Mans Master
Joined: Oct 2008
Posts: 9,758
Likes: 49
From: Houston Texas
My 1985 l98 has about 120k on it, its using about 1.5 quarts of oil between oil changes and starting to use antifreeze. (none in the oil)
I WANT MORE POWER (duh)
I am going to pull the trigger on a rebuild I am looking for about 370hp and 350-400ftlbs of torque (i am using a carb not the TPI.) Open pipes on the stock shorty headers. I dont want to go to radical because i dont want to chnage the 700r, or the rear end.
It is a sunny day DD with occasional runs at Auto cross, drag strip, and top speed. (basically a tire shreader)
I am looking for a good engine rebuild shop preferabale in the Cincinnati Aera.
I also am considering a Crate Engine. Any sugestions on that end would be appreciated.
I am looking to spend in the 3500-5500 range total
Please let me know. I only want to do this once and RELIALIBILTY is the key word here
I WANT MORE POWER (duh)
I am going to pull the trigger on a rebuild I am looking for about 370hp and 350-400ftlbs of torque (i am using a carb not the TPI.) Open pipes on the stock shorty headers. I dont want to go to radical because i dont want to chnage the 700r, or the rear end.
It is a sunny day DD with occasional runs at Auto cross, drag strip, and top speed. (basically a tire shreader)
I am looking for a good engine rebuild shop preferabale in the Cincinnati Aera.
I also am considering a Crate Engine. Any sugestions on that end would be appreciated.
I am looking to spend in the 3500-5500 range total
Please let me know. I only want to do this once and RELIALIBILTY is the key word here
You're assuming he's not ALREADY carbed. If so, he'd have to add the intake/exhaust "peripherals" as part of the project. Doesn't sound likely/desireable for someone not wanting to crack the diff/trans for cost management.
Great foundation if you really want to keep building though. LS7 would be nice!
Great foundation if you really want to keep building though. LS7 would be nice!