90 L98 performance combination. Your thoughts??
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Burning Brakes
Joined: Jan 2001
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From: Manhattan
90 L98 performance combination. Your thoughts??
OK, I have hedman 1 5/8 long tube headers and dual exhaust, free mods, and ported plenum behind the throtle body. I have the 6-speed with 3.33 gears. From most important to least improtant, my goals are: Street performance, Road racing track performance, drag strip, auto-x. Ie, i will make the most compromises for drag strip and auto-x to keep good track and street performance.
Engine: stock, 130,000 miles
Intake: Jeb SP conversion
Cam: LT4 HOT cam kit
Do you think I'm asking too much RPM for my stock bottom end? I figure the HOT cam is good to 6000-6500rpm. How about for 20-30min sessions on the race track?
EDIT: added sig
[Modified by Raistlin, 11:13 AM 1/26/2004]
Engine: stock, 130,000 miles
Intake: Jeb SP conversion
Cam: LT4 HOT cam kit
Do you think I'm asking too much RPM for my stock bottom end? I figure the HOT cam is good to 6000-6500rpm. How about for 20-30min sessions on the race track?
EDIT: added sig
[Modified by Raistlin, 11:13 AM 1/26/2004]
Team Owner
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From: San Pedro CA
Re: 90 L98 performance combination. Your thoughts?? (Raistlin)
ok... you are on the right track...
but with 133k miles, I would consider updating the bottom end...
Scorp508 got a lot of miles out of his stock bottom end, but for some reason, I view that as the exception, and not the rule.
Also, to get anything more than 5000rpm, you will need a better intake. The stock TPI, even ported, is still a real choker... ick.
but with 133k miles, I would consider updating the bottom end...
Scorp508 got a lot of miles out of his stock bottom end, but for some reason, I view that as the exception, and not the rule.
Also, to get anything more than 5000rpm, you will need a better intake. The stock TPI, even ported, is still a real choker... ick.
Team Owner
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From: OBAMA IS HITLER
Re: 90 L98 performance combination. Your thoughts?? (Raistlin)
sounds like a mean setup. you might want to remove those hedmans though, in favor of a better header. i know a local guy who had them, and they warped & leaked like a sieve. if you looked at archives here, you might not like what you see.
Team Owner
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From: Athens AL
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Re: 90 L98 performance combination. Your thoughts?? (Raistlin)
I wouldnt be keeping it over 6K, but I dont think your expectations are that unreasonable. Realize that she will need more care and oil changes should be done on time with the right stuff.
Its been my experience that whatever is going bad will always break at the track.
Its been my experience that whatever is going bad will always break at the track.
Thread Starter
Burning Brakes
Joined: Jan 2001
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From: Manhattan
Re: 90 L98 performance combination. Your thoughts?? (bradvette)
Yep, I've been through the header debates. My hedmans have been no problem. (I had them coated, probably helps a little)
I am thinking about switching to hooker 1 3/4" headers, but not untill I think there will be a performance gain.
My hp guess is ~350 crank hp, limited by stock 113 d-port heads.
I'm horrible about changing oil, but I do use Mobile 1 exclusively. Last time at Watkins Glen I had both the water and oil temp guages pegged. I'm planning on a radiator upgrade before April, hoping that will keep the temps in check.
If I port my 113's do you think there is any reason why it wouldn't run like a HOT cam equipped LT1? i.e. about 430 crank hp? (assuming I don't ruin the heads when I port them :D )
What do you think will be the first thing to break because of excessive RPM? rod bolts?
I am thinking about switching to hooker 1 3/4" headers, but not untill I think there will be a performance gain.
My hp guess is ~350 crank hp, limited by stock 113 d-port heads.
I'm horrible about changing oil, but I do use Mobile 1 exclusively. Last time at Watkins Glen I had both the water and oil temp guages pegged. I'm planning on a radiator upgrade before April, hoping that will keep the temps in check.
If I port my 113's do you think there is any reason why it wouldn't run like a HOT cam equipped LT1? i.e. about 430 crank hp? (assuming I don't ruin the heads when I port them :D )
What do you think will be the first thing to break because of excessive RPM? rod bolts?
Team Owner
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From: SE NY
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Re: 90 L98 performance combination. Your thoughts?? (Raistlin)
I assume you would like to retain bottom end torque so would advise:
-BM style intake base with AS&M LT runners
-ported #113s with larger valves, better rockers, etc
-a nice cam like ZZ-9
-enhanced ignition to support good burn over 5k RPM.
-an AFPR to match fuel to increased air flow at WOT
Go to my site and check out the table with results of mods to a L98. I believe you can get to 370chp with a modified TPI setup. If you are willing to give up a little low end torque you can likely got ~400chp with a mini or super ram intake setup. Of course up here you will likely benefit from 1 3/4" LT headers.
In what event(s) do you want to run with the 400hp+ LT1s?
-BM style intake base with AS&M LT runners
-ported #113s with larger valves, better rockers, etc
-a nice cam like ZZ-9
-enhanced ignition to support good burn over 5k RPM.
-an AFPR to match fuel to increased air flow at WOT
Go to my site and check out the table with results of mods to a L98. I believe you can get to 370chp with a modified TPI setup. If you are willing to give up a little low end torque you can likely got ~400chp with a mini or super ram intake setup. Of course up here you will likely benefit from 1 3/4" LT headers.
In what event(s) do you want to run with the 400hp+ LT1s?
Drifting
Joined: Aug 2000
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From: West Islip New York
Re: 90 L98 performance combination. Your thoughts?? (Raistlin)
Engine: stock, 130,000 miles
Do you think I'm asking too much RPM for my stock bottom end? I figure the HOT cam is good to 6000-6500rpm. How about for 20-30min sessions on the race track?
Do you think I'm asking too much RPM for my stock bottom end? I figure the HOT cam is good to 6000-6500rpm. How about for 20-30min sessions on the race track?
If you think you're going to, might be time to go for a nice 4 bolt. See where your making power, even with the hot cam you might be finished generating anything but noise well before that.
Where you are going road racing in the NY area? I'd love to find a place fairly close.
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Thread Starter
Burning Brakes
Joined: Jan 2001
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From: Manhattan
Re: 90 L98 performance combination. Your thoughts?? (65Z01)
I assume you would like to retain bottom end torque so would advise:
...
In what event(s) do you want to run with the 400hp+ LT1s?
...
In what event(s) do you want to run with the 400hp+ LT1s?
Add in the lower cost of the converted single plane, and ease of installation and I'm willing to try. (Even though i'll give up the good looks of the TPI and SR)
I was just thinking about being able to get similar hp and tq numbers as a HOT cam LT1. The only event i'm interested in times is on a road course. I love drag racing, but will only go to the track to "see what she'll do"
Thread Starter
Burning Brakes
Joined: Jan 2001
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From: Manhattan
Re: 90 L98 performance combination. Your thoughts?? (1MoorTym)
If you think you're going to, might be time to go for a nice 4 bolt. See where your making power, even with the hot cam you might be finished generating anything but noise well before that.
Where you are going road racing in the NY area? I'd love to find a place fairly close.
Where you are going road racing in the NY area? I'd love to find a place fairly close.
I've been to Watkins Glen and am heading up there again with http://www.tracquest.com/ May 17 and 18th. I'm planning to go to 5 or 6 Driver Events with some friends of mine that drive Porsches. http://www.gtc-motorsports.com
Burning Brakes
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From: Cleveland OH
Re: 90 L98 performance combination. Your thoughts?? (Raistlin)
Just a guess on my part here, but I think that if you go with Jeb's Intake or a SuperRam with non-ported D-Ports, you're going to choke the motor without some good porting and upgraded valves on your heads.
If you were going to do heads and cam along with your choice of intake (Jeb's, SR or MR), you could have a better optimized combo.
I would still be concerned with the 130K bottom end and the RPMs that you want to run.
If you wanted to keep it on the cheap, maybe you could just port your existing TPI setup and heads and get the Hot cam kit.
Ron
If you were going to do heads and cam along with your choice of intake (Jeb's, SR or MR), you could have a better optimized combo.
I would still be concerned with the 130K bottom end and the RPMs that you want to run.
If you wanted to keep it on the cheap, maybe you could just port your existing TPI setup and heads and get the Hot cam kit.
Ron
Team Owner
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From: SE NY
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Re: 90 L98 performance combination. Your thoughts?? (Raistlin)
Right you are, on a road course you can likely select the gear with a 6-speed to keep RPMs up in the power band.
So a peaky power curve would be no problem and certainly would yield more HP.
In that case you would do better with a set of BowTie Al heads as they are beefier than the #113s and so less prone to stress cracking that big HP numbers wil bring.
I think you need angine that will run in the 6-7k RPM range which means doing the bottom end as well. You know, build the package to fit your needs.
If you want to wait till this L98 gives up, pocket port your heads along with some good valve train parts, do the cam and siamese the stock intake base. These mods willl allow you to pull strongly to 6k RPM or maybe a little more with minimal investment now.
So a peaky power curve would be no problem and certainly would yield more HP.
In that case you would do better with a set of BowTie Al heads as they are beefier than the #113s and so less prone to stress cracking that big HP numbers wil bring.
I think you need angine that will run in the 6-7k RPM range which means doing the bottom end as well. You know, build the package to fit your needs.
If you want to wait till this L98 gives up, pocket port your heads along with some good valve train parts, do the cam and siamese the stock intake base. These mods willl allow you to pull strongly to 6k RPM or maybe a little more with minimal investment now.
Thread Starter
Burning Brakes
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From: Manhattan
Re: 90 L98 performance combination. Your thoughts?? (HeaderDesign.com)
jburnett is modifing Victor Jr 2975 sp manifold. that's the one i'm thinking about.
I agree the stock heads will severly choke the potential of the hot cam/sp intake combo. I'm just limited living in an apt in the city, so I won't be able to port the heads at the same time i do cam and intake. I'm guessing 350 crank hp from stock heads, a lot more from ported heads. I figure I could do this in two stages, intake/cam then later port my 113's.
Do you think ported 113's would be able to get 430hp (crank) like the LT1's?
I agree the stock heads will severly choke the potential of the hot cam/sp intake combo. I'm just limited living in an apt in the city, so I won't be able to port the heads at the same time i do cam and intake. I'm guessing 350 crank hp from stock heads, a lot more from ported heads. I figure I could do this in two stages, intake/cam then later port my 113's.
Do you think ported 113's would be able to get 430hp (crank) like the LT1's?
Team Owner
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From: SE NY
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Re: 90 L98 performance combination. Your thoughts?? (Raistlin)
I've read that the portedc #113s will flow over 400hp but that they are rather thin compared to aftermarket heads.
Burning Brakes
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From: Cleveland OH
Re: 90 L98 performance combination. Your thoughts?? (Raistlin)
Do you think ported 113's would be able to get 430hp (crank) like the LT1's?
I don't think you'll get 430HP at the crank with just a port job on the 113s. You might come close with a full port/polish job with upgraded valves.
The choice of intake will also affect how much HP you're making. The MR seems to make more HP at the expense of some TQ. The SR is the opposite, and I don't have enough experience with the single plane to make a guess.
However, back to your question, I would say that you won't make 430HP on a simple port job to a d-port 113.
Ron
Thread Starter
Burning Brakes
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From: Manhattan
Re: 90 L98 performance combination. Your thoughts?? (RonRed89)
I found some information from Sallee Chevrolet website. They have upgrades for the ZZ4 engine. Option 6 has a ZZ4 with single plane intake, hot cam, and ported heads w/ larger valves. They say it makes 440hp and 437tq. http://www.sallee-chevrolet.com/Chev...V8s/PUZZ4.html
I guess I'm on the right track. Thanks for all your help.
--steve
I guess I'm on the right track. Thanks for all your help.
--steve
Le Mans Master
Joined: Jun 2002
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From: High Plains Drifter Fayetteville, AR
Re: 90 L98 performance combination. Your thoughts?? (Raistlin)
I found some information from Sallee Chevrolet website. They have upgrades for the ZZ4 engine. Option 6 has a ZZ4 with single plane intake, hot cam, and ported heads w/ larger valves. They say it makes 440hp and 437tq. http://www.sallee-chevrolet.com/Chev...V8s/PUZZ4.html
I guess I'm on the right track. Thanks for all your help.
--steve
I guess I'm on the right track. Thanks for all your help.
--steve
Safety Car
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From: Ohio
Re: 90 L98 performance combination. Your thoughts?? (Raistlin)
I re-read your post on doing the intake and cam first, without doing the heads, and the logic. I think that you will find that A) you will generate additional power over stock, but B) you will then be moving the air restriction to the heads. I don't have any dyno numbers to prove out the statement I'm going to make, but it seems logical that you would likely make as much HP just doing the heads vs. all the expense and pita work doing the other two jobs?? C) you will be 90% of the way to taking the heads off anyway if you do the intake and cam. All the accessories have to be removed to do those two jobs. Why would you want to later do it all over again to get to the heads in the future??