L98 money for mods.. need help
Thread Starter
Instructor
Joined: Jun 2010
Posts: 248
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From: Avon IN
L98 Have money for mods.. need advice
I purchased a beautiful 1989 about 2 weeks ago. I LOVE IT!! Me being an ocd have researched and scoured the forums and web pages for what setups warrant what performance. I have around 5k to play with. I am looking to increase hp and tqs by at least 100 each. I don't want to sacrifice low end tq for more rpms or hp..(I like the miniram but I think I can build a system with good hp on top without loosing the tqs) I want to keep the tpi.
My vette is completely stock.. minus new K&N air filter. 100k on the car, heads have never been off, zf6.
I am thinking about the new BBK SSI intake(new plenum) with 58mm tb's(looks good too), 1.6 roller rockers(not sure who to go with), zz4 cam, pypes header back system(x-pipe), long tube headers.
After that I will have extra cash, would it be a good idea to overhaul an engine that is this old and with 100k?
I want the performance for auto x, occasional strip runs, and road courses. I want to maintain daily drivability.
I am also considering changing it to a 383 on top of those mods. I know there are threads that address topics like this, however I want some opinions on the mods mentioned and advice concerning parts and what not.
http://www.bbkperformance.com/produc...-manifold.html
http://www.pypesexhaust.com/sys-vette2.html
My vette is completely stock.. minus new K&N air filter. 100k on the car, heads have never been off, zf6.
I am thinking about the new BBK SSI intake(new plenum) with 58mm tb's(looks good too), 1.6 roller rockers(not sure who to go with), zz4 cam, pypes header back system(x-pipe), long tube headers.
After that I will have extra cash, would it be a good idea to overhaul an engine that is this old and with 100k?
I want the performance for auto x, occasional strip runs, and road courses. I want to maintain daily drivability.
I am also considering changing it to a 383 on top of those mods. I know there are threads that address topics like this, however I want some opinions on the mods mentioned and advice concerning parts and what not.
http://www.bbkperformance.com/produc...-manifold.html
http://www.pypesexhaust.com/sys-vette2.html
Last edited by cypher85; Jul 21, 2010 at 05:54 PM.
Team Owner
Joined: Sep 2001
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
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My first suggestion is to drive it 6 months, and see how much of that 5K you have to dump into replacement parts. Things like the clutch, wheel bearings, U-joints, shocks, and brakes/alternator are going to cut into that budget significantly unless you do it all yourself.
Secondly, a ZZ4 cam is a horrible waste of the BBK system, which removes your current plenum and runners. 58mm is unnecessary. I would never recommend someone go with a ZZ4 camshaft unless they just wanted a new cam for a stock engine.
Secondly, a ZZ4 cam is a horrible waste of the BBK system, which removes your current plenum and runners. 58mm is unnecessary. I would never recommend someone go with a ZZ4 camshaft unless they just wanted a new cam for a stock engine.
Le Mans Master
Joined: Jun 2006
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From: One day you're a Comet...the next day you're dust... Arkansas
Don't get in a big hurry and don't fall for gimmicks. You won't need a new throttle body to meet your goals.
If you want to add 100 chp and keep TPI concentrate your money on the very best heads / cam / exhaust system you can find.
In the meantime you can remove the frisbee, cut the filter lid, and get a new stock filter. Also do a throttle body bypass. It will make working on the car easier.
If you want to add 100 chp and keep TPI concentrate your money on the very best heads / cam / exhaust system you can find.
In the meantime you can remove the frisbee, cut the filter lid, and get a new stock filter. Also do a throttle body bypass. It will make working on the car easier.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
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From: Australia
has been adv since Oct 2004 and still doesn't exist
http://www.thirdgen.org/techboard/po...3-post982.html
http://www.thirdgen.org/techboard/tp...ake-setup.html
Race Director
Joined: Nov 2003
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
A 383 with a miniram will have more torque (everywhere) than what you're running now. The longer stroke of the 383 makes up for any "loss" converting from a long tube to a short tube setup. The extra power of better heads/cam takes you up from there.
You could end up nearly 200hp higher if you go that route. (220rwhp stock, 420rwhp with a built 383).
You could end up nearly 200hp higher if you go that route. (220rwhp stock, 420rwhp with a built 383).
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
My first suggestion is to drive it 6 months, and see how much of that 5K you have to dump into replacement parts. Things like the clutch, wheel bearings, U-joints, shocks, and brakes/alternator are going to cut into that budget significantly unless you do it all yourself.
Secondly, a ZZ4 cam is a horrible waste of the BBK system, which removes your current plenum and runners. 58mm is unnecessary. I would never recommend someone go with a ZZ4 camshaft unless they just wanted a new cam for a stock engine.
Secondly, a ZZ4 cam is a horrible waste of the BBK system, which removes your current plenum and runners. 58mm is unnecessary. I would never recommend someone go with a ZZ4 camshaft unless they just wanted a new cam for a stock engine.
Add another $3-5k and you might have enough to do it "right". Then, plan on more money for a paint job interior restoration, etc...unless you want a sleeper.
Last edited by GREGGPENN; Jul 21, 2010 at 06:47 PM.
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My first suggestion is to drive it 6 months, and see how much of that 5K you have to dump into replacement parts. Things like the clutch, wheel bearings, U-joints, shocks, and brakes/alternator are going to cut into that budget significantly unless you do it all yourself.
Secondly, a ZZ4 cam is a horrible waste of the BBK system, which removes your current plenum and runners. 58mm is unnecessary. I would never recommend someone go with a ZZ4 camshaft unless they just wanted a new cam for a stock engine.
Secondly, a ZZ4 cam is a horrible waste of the BBK system, which removes your current plenum and runners. 58mm is unnecessary. I would never recommend someone go with a ZZ4 camshaft unless they just wanted a new cam for a stock engine.
Thread Starter
Instructor
Joined: Jun 2010
Posts: 248
Likes: 2
From: Avon IN
Vader that is good advice, I have already replaced the alternator and master/slave clutch cylinders. The only thing that doesn't work on the car is the ride select.. which I am working on now.
I like the idea of rebuilding the engine and servicing old parts, didn't think about the U-joints. I also like the idea of a 383 with a miniram and good heads/cam. I think one thing that I will do now is headers and exhaust. Thanks all for the advice!
I like the idea of rebuilding the engine and servicing old parts, didn't think about the U-joints. I also like the idea of a 383 with a miniram and good heads/cam. I think one thing that I will do now is headers and exhaust. Thanks all for the advice!
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Instructor
Joined: Jul 2010
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From: Chicago IL
Start with exhaust (LT's and back) with a good short ram. Have the suspension etc. inspected to see what kind of condition everything is in. Look for a good heads/cam and then worry about the clutch. The TB bypass is easy and worth it find someone to port/polish the TB while you are at it. The exterior and interior are beautiful don't worry about those except for wheels 
btw this is Ryan
btw this is Ryan
Burning Brakes
Joined: Jun 2008
Posts: 892
Likes: 1
From: New Smyrna Beach Florida
My first suggestion is to drive it 6 months, and see how much of that 5K you have to dump into replacement parts. Things like the clutch, wheel bearings, U-joints, shocks, and brakes/alternator are going to cut into that budget significantly unless you do it all yourself.
Secondly, a ZZ4 cam is a horrible waste of the BBK system, which removes your current plenum and runners. 58mm is unnecessary. I would never recommend someone go with a ZZ4 camshaft unless they just wanted a new cam for a stock engine.
Secondly, a ZZ4 cam is a horrible waste of the BBK system, which removes your current plenum and runners. 58mm is unnecessary. I would never recommend someone go with a ZZ4 camshaft unless they just wanted a new cam for a stock engine.
I also have an 89. At 80,000 mi., 6 months after purchase, I had to replace the injectors and head gaskets. This is a very common problem. They simply rust out. The injectors get eaten up by the ethanol in the fuel. It will eventually give you problems. FIC injectors is very reasonable.Great choice in the year!!!
Thread Starter
Instructor
Joined: Jun 2010
Posts: 248
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From: Avon IN
I also have an 89. At 80,000 mi., 6 months after purchase, I had to replace the injectors and head gaskets. This is a very common problem. They simply rust out. The injectors get eaten up by the ethanol in the fuel. It will eventually give you problems. FIC injectors is very reasonable.Great choice in the year!!!
Last edited by cypher85; Jul 22, 2010 at 02:44 PM.
Safety Car
Joined: Feb 2000
Posts: 4,564
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From: Austin Texas
Have a read on my web site...I don't know how much the pricing has changed since I did my rebuild but it gives you a good idea of what it takes and how much it cost me.
Most of the pertinent info is under "Recipe for a 400 HP L98". Part 2 has the list of parts we used (part #'s and cost). It is still a TPI, has great street manners and smokes most in it's path.
I went with TPIS longtubes with a Corsa LT1 dual exhaust. Used (2) Random Tech cats.
Good luck on the build
Most of the pertinent info is under "Recipe for a 400 HP L98". Part 2 has the list of parts we used (part #'s and cost). It is still a TPI, has great street manners and smokes most in it's path.
I went with TPIS longtubes with a Corsa LT1 dual exhaust. Used (2) Random Tech cats.
Good luck on the build
Slingshot
Joined: Dec 2001
Posts: 3,817
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From: Charlotte NC
Its funny you mentioned the injectors. They were all replaced on the car about a year ago, along with the fuel rails. The reciept shows that it was a 1200 dollar project.. Glad that has been taken care of. Not sure about the head gasket tho. One issue I am dealing with is oil leaks out of somewhere when I punch it, engine smokes from the passenger side. Initially I assumed it was the valve cover gaskets, however after more investigation it looks like the oil is coming out of somewhere below the valve covers. I can't quite pinpoint it. Normal driving everything is fine, only under hard acceleration does this issue present itself.
Race Director
Joined: Nov 2003
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
Where did you get white smoke from??? The color white is not mentioned up til now....and white smoke usually implies coolant leaking into the cylinder -- not seal/guide leaks.
Thread Starter
Instructor
Joined: Jun 2010
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From: Avon IN
1991Z07 your page is very informative, I will definitely use your recipe as a reference point!
Le Mans Master
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From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
If you can pinpoint the oil as coming out of the dipstick, you might just get new hoses on your breather and the PCV valve. after 20 or so years, the deposits neck the inside of the tubes down, and it just can't breathe as good. Then, when you nail it, the extra pressure that blows by the rings has nowhere to go except dipstick and seals.
Thread Starter
Instructor
Joined: Jun 2010
Posts: 248
Likes: 2
From: Avon IN
If you can pinpoint the oil as coming out of the dipstick, you might just get new hoses on your breather and the PCV valve. after 20 or so years, the deposits neck the inside of the tubes down, and it just can't breathe as good. Then, when you nail it, the extra pressure that blows by the rings has nowhere to go except dipstick and seals.
