LS6 intake manifold
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From: Waddell Arizona
LS6 intake manifold
I' m thinking about purchasing a LS6 intake manifold for my 99 coupe. Will I gain any horsepower with this unit? How hard is it to install? Any advice good or bad is appreciated.
Gary
Gary
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From: Coconut Creek FL
Originally Posted by grunz95
I' m thinking about purchasing a LS6 intake manifold for my 99 coupe. Will I gain any horsepower with this unit? How hard is it to install? Any advice good or bad is appreciated.
Gary
Gary
Well having done one on a pretty much stock 97 - I have to disagree with the post above that says pass...I noticed a very nice increase in throttle response along with an engine that really came alive above 2500 RPM. I did not dyno tune or anything for this install....but the seat of the pants was enough to tell me it was worth the $300 I paid...the install is not difficult but you will need to convert to the newer style coolant lines. The older LS1 coolant lines run under the manifold in the void that is there by design, the new LS1\6 intake does not have this open area under it (hence the larger runners) so the line will not work (at least with out modification)
go here: http://ls1howto.com/index.php?article=5
it shows step by step install along with the part numbers for the required stuff you will need.
If you are planning any future modifications (Long Tube headers, cam or heads) it will behoove you to have this already...
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Joined: Jun 2003
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From: Coconut Creek FL
Originally Posted by idiedtrying
where is a good place to buy the ls6 manifold??
Start in the parts for sale section- there is usually 1 or 2 to be found. You may even want to start a thread in there asking to buy one. Most can be had slightly used for around $300 (this is where I got mine) the coolant lines I got from my local Chevy dealer- I used the part numbers in the link I posted to buy them...oh, if you need the 8 O-Ring type gaskets (most can be reused if they are in OK shape) buy them from FAST http://www.powerandperformancenews.c...Category_Code= best price around (about half of what GM would charge)
Hope this helps!
Le Mans Master
Joined: Aug 2000
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From: Suffolk, Long Island NY
Originally Posted by byte_me
Well having done one on a pretty much stock 97 - I have to disagree with the post above that says pass...I noticed a very nice increase in throttle response along with an engine that really came alive above 2500 RPM. I did not dyno tune or anything for this install....but the seat of the pants was enough to tell me it was worth the $300 I paid..
IMO, seat of the pants is the worst way to judge a performance increase or decrease. There's no way someone can feel 5-10 HP on a 350+HP car.
I had a before and after dyno done. I didn't even see a 5 HP gain on my stock heads/cam car. I'd wait till you install a cam or at least headers.
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From: Whippany NJ
CI 6-7-8-9 Veteran
St. Jude Donor '08-'09
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Originally Posted by 90droptopp
Is your car stock? Are you planning heads and cam later? If the car is staying more or less stock, pass on the intake.
Most mods need combination to make them work well. Intake manifold alone does nothing.
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Joined: Mar 2004
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From: Waddell Arizona
Originally Posted by idiedtrying
do CAI or exhaust first.. theres a lot about the ls6 manifolds on here, just do a searsh, you will find all kinds of posts
your in hammond?? im in valparaiso
your in hammond?? im in valparaiso
Gary
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Joined: Jun 2003
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From: Coconut Creek FL
Originally Posted by Face
IMO, seat of the pants is the worst way to judge a performance increase or decrease. There's no way someone can feel 5-10 HP on a 350+HP car.
I had a before and after dyno done. I didn't even see a 5 HP gain on my stock heads/cam car. I'd wait till you install a cam or at least headers.
OK...so let me re-post what I said I did IN FACT get out of the car, that was not there before the LS6 intake...so either the intake did in fact do this - or it was that pixie dust that I sprinkled around it before I drove it...
"I noticed a very nice increase in throttle response along with an engine that really came alive above 2500 RPM"
there have been others that have also gotten good results from doing the swap - Just so you know, a dyno is not 100% accurate - weather conditions and the setup can make or break you, besides there is a "re-learn" process the computer does to understand what has changed, perhaps yours was dyno'd before the computer understood the difference - a "dyno tune" would probably have been the way to go for you...
Racer
Joined: Nov 2005
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From: Murrieta Ca..... America, fun while it lasted
Originally Posted by byte_me
OK...so let me re-post what I said I did IN FACT get out of the car, that was not there before the LS6 intake...so either the intake did in fact do this - or it was that pixie dust that I sprinkled around it before I drove it...
"I noticed a very nice increase in throttle response along with an engine that really came alive above 2500 RPM"
there have been others that have also gotten good results from doing the swap - Just so you know, a dyno is not 100% accurate - weather conditions and the setup can make or break you, besides there is a "re-learn" process the computer does to understand what has changed, perhaps yours was dyno'd before the computer understood the difference - a "dyno tune" would probably have been the way to go for you...
"I noticed a very nice increase in throttle response along with an engine that really came alive above 2500 RPM"
there have been others that have also gotten good results from doing the swap - Just so you know, a dyno is not 100% accurate - weather conditions and the setup can make or break you, besides there is a "re-learn" process the computer does to understand what has changed, perhaps yours was dyno'd before the computer understood the difference - a "dyno tune" would probably have been the way to go for you...
Or maybe you need to justify the $300 you spent....... Plenty of us on this board have "been there and done that". To the initial poster, when g.m. swapped it as the standard intake, they raised the h.p. rating 5 gross h.p. Think about it.
Drifting
Joined: Jun 2000
Posts: 1,872
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From: St. Louis MO
It's not the HP that delivers the "SOTP" performance gain, it's the torque. If you look @ the 00 vs. 01 specs, there's a significant (earlier) torque gain with the new intake. With a more aggressive cam in the 2000, you should be able to feel it. Anyone have any dyno #'s that would confirm this with a 2000?
Burning Brakes
Joined: Oct 2004
Posts: 931
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From: Rowlett, Texas
I installed an lS6 manifold on my mildly modified 2000 last week. It felt pretty sluggish, actually worse, for the first 100 miles. But now I notice better throttle response, and an engine that comes alive above 2500. Hmmmm.
Of course, you guys are right - spend $300 & it damn well is gonna run better in your mind!
I'll get it dyno'd and Edit-tweaked next week, but unfortunately I have done some exhaust work also since my last dyno, so I won't be able to judge just the effect of the manifold.
Yes, the '01 had 5 hp and 25 lbft more than the '00.
Changes were: smaller cam, LS6 intake manifold, bigger maf, bigger air filter opening, cast-iron exhaust manifolds. So, what did each of these contribute to the 25 lb-ft - who knows - Just do'em all, except the cam, ha.
Cheers,
DG
Of course, you guys are right - spend $300 & it damn well is gonna run better in your mind!
I'll get it dyno'd and Edit-tweaked next week, but unfortunately I have done some exhaust work also since my last dyno, so I won't be able to judge just the effect of the manifold.
Yes, the '01 had 5 hp and 25 lbft more than the '00.
Changes were: smaller cam, LS6 intake manifold, bigger maf, bigger air filter opening, cast-iron exhaust manifolds. So, what did each of these contribute to the 25 lb-ft - who knows - Just do'em all, except the cam, ha.
Cheers,
DG
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From: Coconut Creek FL
As the poster above mentioned, there is more to it then 5 HP - there is also torque to be had from this...
The order of Mods I did are this:
LS6 intake and Haltech Stinger
Kooks Long tube headers - high flow cats - Xpipe
Z06 titanium catback (keeps the highway noise to a minimum
Underdrive crank pulley
As I eluded to above - the LS6 intake along with the Haltech setup made a nice change in the cars attitude. So despite what anyone wants to say, there was a noticable difference.
To answer the one post stating that I am trying to justify the $300 expense - well, all I can say is what I know the car did afterward...and it was worth the $$ in my book - especially now that I have done a few more mods...so look at it like this, it was good on the stock car and allowed me to get even more out of the future mods I did.
Increasing a cars ability to pull in more air and exhaust it GREATLY increases the cars performance. Basic concepts of a 4 stroke engine (Suck, squeeze, bang and blow) The more you suck, the more you squeeze, the bigger the bang the more it can blow...just like some opinions on this board!
The order of Mods I did are this:
LS6 intake and Haltech Stinger
Kooks Long tube headers - high flow cats - Xpipe
Z06 titanium catback (keeps the highway noise to a minimum
Underdrive crank pulley
As I eluded to above - the LS6 intake along with the Haltech setup made a nice change in the cars attitude. So despite what anyone wants to say, there was a noticable difference.
To answer the one post stating that I am trying to justify the $300 expense - well, all I can say is what I know the car did afterward...and it was worth the $$ in my book - especially now that I have done a few more mods...so look at it like this, it was good on the stock car and allowed me to get even more out of the future mods I did.
Increasing a cars ability to pull in more air and exhaust it GREATLY increases the cars performance. Basic concepts of a 4 stroke engine (Suck, squeeze, bang and blow) The more you suck, the more you squeeze, the bigger the bang the more it can blow...just like some opinions on this board!
Burning Brakes
Joined: Oct 2001
Posts: 812
Likes: 13
From: Houston TX
My oil sender unit failed , So since I was removing the ls1 manifold. I replace it with a LS6 and had it dyno my gain was 15 hp. It ran little lean add little fuel and got 17 hp. ( MTI, LS1-edit lG headers) 
