Is it Worth it ???
Thread Starter
Race Director
Joined: Oct 1999
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From: Somers NY
Is it Worth it ???
I'm trying to stay within a budget... and would like to know what kind of increase in HP or 1/4 mile time...
I don't even know if the following is worth the time & $$)
I have an LS2 with Vararam, Kooks Headers, and a good tune.. it has run a best of 11.98 @ 117 mph..
Would I see any improvement if I just change the rockers to 1.8 (with better springs, and give the intake a good porting, and retune it...???
I know to change the cam I most likely should go to a higher stall converter, "BUT" thats when the $$ starts getting out of hand
If I ran 12.00 as is.. with just the 1.8 RR and ported intake would I see an improvement of .10 or .15 ??
Thanks
I don't even know if the following is worth the time & $$)
I have an LS2 with Vararam, Kooks Headers, and a good tune.. it has run a best of 11.98 @ 117 mph..
Would I see any improvement if I just change the rockers to 1.8 (with better springs, and give the intake a good porting, and retune it...???
I know to change the cam I most likely should go to a higher stall converter, "BUT" thats when the $$ starts getting out of hand
If I ran 12.00 as is.. with just the 1.8 RR and ported intake would I see an improvement of .10 or .15 ??
Thanks
Last edited by jpee; Jan 28, 2012 at 04:13 PM.
Burning Brakes
Joined: Jan 2010
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From: Orient Oh
There's a lot better ways to spend that kind of cash... heads ported,springs, and rocker arms with a re-tune... I wanna say about 14-1900 there.. If I was you.. just get spare set of gto fronts and fast 102 with ported tb.. You can find gto spares fairly cheap and with this set up you'll see a lot more off your 1/4 et and best bang for the buck. If you do the work yourself cam package would be your best bet. You can get a really good cam from spinmonster
Race Director
Joined: Mar 2005
Posts: 11,549
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From: Southampton NJ
I'm trying to stay within a budget... and would like to know what kind of increase in HP or 1/4 mile time...
I don't even know if the following is worth the time & $$)
I have an LS2 with Vararam, Kooks Headers, and a good tune.. it has run a best of 11.98 @ 117 mph..
Would I see any improvement if I just change the rockers to 1.8 (with better springs, and give the intake a good porting, and retune it...???
I know to change the cam I most likely should go to a higher stall converter, "BUT" thats when the $$ starts getting out of hand
If I ran 12.00 as is.. with just the 1.8 RR and ported intake would I see an improvement of .10 or .15 ??
Thanks
I don't even know if the following is worth the time & $$)
I have an LS2 with Vararam, Kooks Headers, and a good tune.. it has run a best of 11.98 @ 117 mph..
Would I see any improvement if I just change the rockers to 1.8 (with better springs, and give the intake a good porting, and retune it...???
I know to change the cam I most likely should go to a higher stall converter, "BUT" thats when the $$ starts getting out of hand
If I ran 12.00 as is.. with just the 1.8 RR and ported intake would I see an improvement of .10 or .15 ??
Thanks
tommyd went 11.3s, i went very good times, and you will to. just ask marc and he will tell you how
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From: St. Louis, MO
St. Jude Donor '08
Thread Starter
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From: Somers NY
s with your suggestion. I have about 2 months to make my decision (thats when I'll get my tax return 
And the track won't open until March... I should have a plan in place by then...
Team Owner
Joined: Feb 2001
Posts: 27,246
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From: Short Hills, NJ
I don't think the rockers are a cost effective mod either. He might see a full tenth reduction in ET from them but he won't be doing the work himself so the final cost of a mod like that might not justify the end results (or even lack thereof).
That would've been one of the first things I'd suggest for him as well 
except for one thing, he has the Z51 brakes and GTO spares don't fit over them without the use of spacers (which add cost, complexity and could possibly compromise bearing life and safety (according to some at least).
But even if they did fit, John was never much of a 'skinnies/weight reduction' kind of guy.
I do still like the converter and used FAST 90/92mm (or new FAST 102mm if need be) along with a ported stock throttle body idea as well.
except for one thing, he has the Z51 brakes and GTO spares don't fit over them without the use of spacers (which add cost, complexity and could possibly compromise bearing life and safety (according to some at least).But even if they did fit, John was never much of a 'skinnies/weight reduction' kind of guy.
I do still like the converter and used FAST 90/92mm (or new FAST 102mm if need be) along with a ported stock throttle body idea as well.
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From: St. Louis, MO
St. Jude Donor '08
That would've been one of the first things I'd suggest for him as well
except for one thing, he has the Z51 brakes and GTO spares don't fit over them without the use of spacers (which add cost, complexity and could possibly compromise bearing life and safety (according to some at least).But even if they did fit, John was never much of a 'skinnies/weight reduction' kind of guy.
I do still like the converter and used FAST 90/92mm (or new FAST 102mm if need be) along with a ported stock throttle body idea as well.
Keep in mind, you can get put on c5 rotors and caliper mounts, which are cheap, and then you can run the GTO spares with no spacers. That's what I do.
The skinnies and taking the passenger seat out have a surprisingly big effect for low cost...where else can you get a consistent .15 -.20 for around $400 incl. wheels/tires/caliper mounts/rotors? Even a converter doesn't have that cost/benefit ratio.
Last edited by Joe_G; Jan 29, 2012 at 10:23 AM.
Burning Brakes
Joined: Jan 2010
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From: Orient Oh
I would only run the gto fronts on track days... Get a intake manifold for sure. The ls2 manifold restricts so much and even a fully ported ls2 intake wont compare to any fast intake. You can find used fasts 600-800 shipped then sell your ls2 for about 200$ so about a 400$ upgrade and there easy to install. You don't need to port the fast but recommended. I'm a DYI kinda guy and I would get a und pulley with the cash saved from getting the fast ported. If you was local I would charge you a 12 pack of beer and a pizza for entire install But a converter now... That's like a 500-600$ labor removal/install at shops but is a must for auto guys if they wanna go fast 
That's about a weekend project for me but I wouldn't charge that much
But a converter now... That's like a 500-600$ labor removal/install at shops but is a must for auto guys if they wanna go fast That's about a weekend project for me but I wouldn't charge that much
Tech Contributor
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From: St. Louis, MO
St. Jude Donor '08
I should add that I just recently learned that if I put the jack under the jacking point behind the front wheel, I can lift both wheels on that side of the car up, making the swap from street tires to skinnies/drag radials much quicker than when I had to drive on boards to get the jack under the front cradle.
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From: Peoria/Phoenix AZ
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The rockers require new springs and are a minimal gain. Pretty much nobody does this mod and that's for a reason. I also wonder...but cannot prove...that some of the valve guide wear issues the Z06 guys are having, dropping valves and ruining engines, might be caused by their 1.8 rocker ratio?? That's a pretty big lever ratio.
Keep in mind, you can get put on c5 rotors and caliper mounts, which are cheap, and then you can run the GTO spares with no spacers. That's what I do.
The skinnies have a surprisingly big effect for low cost...where else can you get a consistent .15 -.20 for around $400 incl. wheels/tires/caliper mounts/rotors? Even a converter doesn't have that cost/benefit ratio.
Keep in mind, you can get put on c5 rotors and caliper mounts, which are cheap, and then you can run the GTO spares with no spacers. That's what I do.
The skinnies have a surprisingly big effect for low cost...where else can you get a consistent .15 -.20 for around $400 incl. wheels/tires/caliper mounts/rotors? Even a converter doesn't have that cost/benefit ratio.
I agree the 1.8 rockers are not a cost effective and safe approach, but skinnies for John is not safe either. He's damn near as old as me, so changing wheels/tires every week to go racing is hard on the body. And driving to/from the track on skinnies is not the best idea either.
A converter is a one time expense that will meet the ET goal and not cause any other issues.
BTW, a ported TB on an automatic has little to no value at the track.
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St. Jude Donor '08
Although you are correct - I need to add I'd taken my seat out when I put the skinnies on...but the results are proven time and time again in my car. No need to test further. I have a couple of videos to prove it as a matter of fact.
Here are two runs with street tires.
This run, along with the one in my sig, is with skinnies. While this run is a 1.49 I hit the rev limiter making the 1-2.
I've got a spreadsheet of all my runs. Before skinnies I was a 11.2 car pushing the launch, and after skinnies, 11.0-11.1 car depending upon how hard I want to push the launch. I got 1-2 mph out of them also.
There's a reason all the fast guys run skinnies, they work!
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From: Southampton NJ
No way are you getting .15-.20 from skinnies. I challenge you to make two passes without the skinnies and then two with them and post the difference. No sandbagging either.
I agree the 1.8 rockers are not a cost effective and safe approach, but skinnies for John is not safe either. He's damn near as old as me, so changing wheels/tires every week to go racing is hard on the body. And driving to/from the track on skinnies is not the best idea either.
A converter is a one time expense that will meet the ET goal and not cause any other issues.
BTW, a ported TB on an automatic has little to no value at the track.
I agree the 1.8 rockers are not a cost effective and safe approach, but skinnies for John is not safe either. He's damn near as old as me, so changing wheels/tires every week to go racing is hard on the body. And driving to/from the track on skinnies is not the best idea either.
A converter is a one time expense that will meet the ET goal and not cause any other issues.
BTW, a ported TB on an automatic has little to no value at the track.
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Joined: Sep 2007
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From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
Race Director
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From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
OK, now that you say the seat's out too, then I can believe it. I just didn't want jpee to think that skinnies alone were good for that much.
Thread Starter
Race Director
Joined: Oct 1999
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From: Somers NY
I'm going to "HAVE" to go to a converter, and cam... "all is good"
I'll get my 11.5 this yr.. I might have to go on food stamps, or ask "Obama" for a "bailout" but I'll make 11.5 
Team Owner
Joined: Feb 2001
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From: Short Hills, NJ
I know I'll need "MORE" than just removing the seats, and putting on a set of skinnies to run 11.5...
I'm going to "HAVE" to go to a converter, and cam... "all is good" I'll get my 11.5 this yr.. I might have to go on food stamps, or ask "Obama" for a "bailout" but I'll make 11.5
I'm going to "HAVE" to go to a converter, and cam... "all is good"
I'll get my 11.5 this yr.. I might have to go on food stamps, or ask "Obama" for a "bailout" but I'll make 11.5 And remember John, to run our Pro 11.50 index it's not just about being able to touch the 11.5s with say an 11.59, you really need to be able to run 11.3s/low 11.4s in any weather, especially if you plan on deep staging in order to cut that better light.
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St. Jude Donor '08
Marc, I know how the NHRA rules work for classes at national events - each class has an "index" with a dial they run when running against cars out of their class...but it's heads up against another class member and you better be a second below the "index" to compete.
How do you guys run your "index" classes? All cars are in the same index, so what happens if you break out?
Team Owner
Joined: Feb 2001
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From: Short Hills, NJ
A little off topic but I hope you don't mind educating me!
Marc, I know how the NHRA rules work for classes at national events - each class has an "index" with a dial they run when running against cars out of their class...but it's heads up against another class member and you better be a second below the "index" to compete.
How do you guys run your "index" classes? All cars are in the same index, so what happens if you break out?
Marc, I know how the NHRA rules work for classes at national events - each class has an "index" with a dial they run when running against cars out of their class...but it's heads up against another class member and you better be a second below the "index" to compete.
How do you guys run your "index" classes? All cars are in the same index, so what happens if you break out?
In our 11.50 indexes, breaking out (where neither one went red at the tree of course) is an automatic loss. In the event of a double break out the one who broke out by less (if one goes 11.45 and the other goes 11.48, then the 11.48 wins) regardless of reaction times as the tree goes out the window when anyone goes under/breaks out.