intake manifold upgrade?
Thread Starter
Instructor
Joined: May 2005
Posts: 247
Likes: 0
From: Ramona CA
intake manifold upgrade?
I have to change the oil pressure sensor on my 99. Is it worth the cost of a higher performing manifold to replace the stock one? My car is not modded, other than the air filter box is cut out. I probably won't do much else to it mod-wise, but if a new better manifold helps a lot I might consider it now that I'll have it apart. 
Racer
Joined: Aug 2006
Posts: 301
Likes: 0
From: GA
Originally Posted by vettenuts
The LS6 intake would be a good upgrade, but you will also need to modify the head cooling system lines to fit it on.
TIA.,
DBLX
Drifting
Joined: May 2005
Posts: 1,590
Likes: 1
From: Littleton Colorado
Do some searches here, the ls6 intake is popular for the pre-2001 Vettes. I did mine and liked it. The difference in HP probably can't be detected with a dyno, but I swear it runs a little better. Its not real had to swap it yourself. Look on ls1tech.com and search here for instructions on replacing the oil pressure sending unit. You pretty much have to take the manifold off to do it.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
The LS6 intake was introduced in the later cars and flows better than the original LS1 intake. Looks exactly the same from the top, but the bottom gets closer to the valley cover under the intake. As a result, when you do the swap you also need to make a few other minor modifications to get it to fit correctly.
Check this out, it explains it pretty good.
Link to intake swap
Check this out, it explains it pretty good.
Link to intake swap
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Team Owner
Joined: Mar 1999
Posts: 22,025
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From: At the beach in little Rhody
Melting Slicks
Joined: Oct 2006
Posts: 2,228
Likes: 5
From: Gainesville Georgia
Originally Posted by skelly1
I have to change the oil pressure sensor on my 99. Is it worth the cost of a higher performing manifold to replace the stock one? My car is not modded, other than the air filter box is cut out. I probably won't do much else to it mod-wise, but if a new better manifold helps a lot I might consider it now that I'll have it apart.
Racer
Joined: Aug 2006
Posts: 404
Likes: 0
From: Napa Ca
Originally Posted by vettenuts
25 hp for around $400 is $17/hp, which is a bargain compared to other mods. The LS1 intake will also severely limit the gains from any other mod as well.
he wont even come close to 25hp unless he really mods the car. that guys hp rating after the dyno was 405 to the wheels. but he will see IMHO around 10-15 at most.
Le Mans Master
Joined: Dec 2003
Posts: 5,561
Likes: 448
From: Atlanta metro Ga.
Originally Posted by blackc598
he wont even come close to 25hp unless he really mods the car. that guys hp rating after the dyno was 405 to the wheels. but he will see IMHO around 10-15 at most.
Hell, I'd do the swap (and might at some point) for a solid 10HP. The general consensus is it's worth about 5HP. That 25HP post raised some eyebrows; I felt there was more to the story (maybe the car was tuned as well).
Drifting
Joined: Dec 2005
Posts: 1,720
Likes: 3
From: East Hampton CT
It's not all about hp with the LS6 intake. It gives a lot better flow for increased TORQUE down low too. I have heard/seen that the FAST 78 or 90's lose a little low end from the LS6. General consensus is that the LS6 is worth approx 5-8rwhp and at least that in torque over the LS1 intake. It will be worth more if you did heads and cam.
Melting Slicks
Joined: May 2000
Posts: 2,498
Likes: 4
From: Brentwood TN
Originally Posted by blackc598
he wont even come close to 25hp unless he really mods the car. that guys hp rating after the dyno was 405 to the wheels. but he will see IMHO around 10-15 at most.
Without other mods to handle additional air flow, the manifold by itself yields horsepower increases that may be within the measurement error of the dyno according to an article a few years ago in Corvette Fever. There's a post on here somewhere I will try to find so I can give the author proper credit, but he said that he picked up no more than about 4 or 5 hp and that was measured on a dyno and I think was with a tune. If headers, a cam and some other breathing/exhaust improvements are made, the manifold makes another 15 ponies or so.
Save the money.
Charlie
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Originally Posted by blackc598
he wont even come close to 25hp unless he really mods the car. that guys hp rating after the dyno was 405 to the wheels. but he will see IMHO around 10-15 at most.
I still think on a dollar per hp basis its likely better than headers and still a good buy though, look how much people are paying for the FAST setup.
Racer
Joined: Aug 2006
Posts: 404
Likes: 0
From: Napa Ca
Originally Posted by kingsey
Would it be worth it with headers, exhuast and a cai?
yes thats what i have on my car ... IMHO best thing to do is intake, lt and xpipe and then the intake manifold after these upgrades get a tune. should see a good 20-30 hp increase to the wheels. someone correct me if im wrong??
Racer
Joined: Aug 2002
Posts: 253
Likes: 1
From: Bossier city, Louisiana
This might help, it's a copy of an article from Corvette Fever, (Sept. 2004) that ran comparisions between FAST, LS1, LS6 with a stock engine, and with a cammed/header engine, on the dyno.
http://www.timelesscharms.net/ls1/co...on/compare.htm
http://www.timelesscharms.net/ls1/co...on/compare.htm