Ported LS6 TB vs. Ls2 90??
Thread Starter
Le Mans Master
Joined: Feb 2001
Posts: 6,777
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From: West "By God" Virginia
CI 7-8-9-10 Veteran
Ported LS6 TB vs. Ls2 90??
I currently have a ported LS6 throttle body with my Fast 90 intake on my H/C Z now, would there be any gains, pros/cons, going with an ls2 90 tb? For those that will ask, I don't know exactly what was done to my stock tb, other than it was ported(on the car when I bought it). I believe the factory ls6 tb is 78mm, does anyone know how far out they can be ported? Any incite would be great, thanks!!
Burning Brakes
Joined: Nov 2004
Posts: 1,226
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From: Lakemoor IL
I would switch over to an LS2 setup. The whole point of running a FAST 90 is so you can use a 90mm TB.
You should be able to get a ported LS2 for around $300. Then sell your 78mm TB for $150 and the cost is minimal.
You should be able to get a ported LS2 for around $300. Then sell your 78mm TB for $150 and the cost is minimal.
Team Owner
Joined: Mar 1999
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From: At the beach in little Rhody
Burning Brakes
Joined: Nov 2004
Posts: 1,226
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From: Lakemoor IL
Maybe he has a FAST 78 and is confusing it for a 90.
Team Owner
Joined: Mar 1999
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From: At the beach in little Rhody
Instructor
Joined: Jan 2006
Posts: 214
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From: Middletown Delaware
Yeah u have to check out, you either have a 78 w ls6 or a 90 with a ls2(or other 90tb) already. If you have a 78 and upgrade to a 90 w/ls2 you would also need a harness (about $50).
I wouldn't think the expense of a new Fast 90 and LS2 tb would be worth it. Better off spending a grand on a N2O kit.
I wouldn't think the expense of a new Fast 90 and LS2 tb would be worth it. Better off spending a grand on a N2O kit.
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Burning Brakes
Joined: Nov 2004
Posts: 1,226
Likes: 3
From: Lakemoor IL
Yeah u have to check out, you either have a 78 w ls6 or a 90 with a ls2(or other 90tb) already. If you have a 78 and upgrade to a 90 w/ls2 you would also need a harness (about $50).
I wouldn't think the expense of a new Fast 90 and LS2 tb would be worth it. Better off spending a grand on a N2O kit.
I wouldn't think the expense of a new Fast 90 and LS2 tb would be worth it. Better off spending a grand on a N2O kit.
I used a plug and play harness($50) that works great.
Instructor
Joined: Jan 2006
Posts: 214
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From: Middletown Delaware
Still what kind of differnce in performance would u think he would get with spending $350 for shell $300 for ported tb and $50 for harness.
Thread Starter
Le Mans Master
Joined: Feb 2001
Posts: 6,777
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From: West "By God" Virginia
CI 7-8-9-10 Veteran
I have pretty good #'s, 450whp, and 416tq w/a 228 cam, so I don't think the cost of upgrading would be worth the minimal gains.
Yeah u have to check out, you either have a 78 w ls6 or a 90 with a ls2(or other 90tb) already. If you have a 78 and upgrade to a 90 w/ls2 you would also need a harness (about $50).
I wouldn't think the expense of a new Fast 90 and LS2 tb would be worth it. Better off spending a grand on a N2O kit.
I wouldn't think the expense of a new Fast 90 and LS2 tb would be worth it. Better off spending a grand on a N2O kit.
Instructor
Joined: Jan 2006
Posts: 214
Likes: 5
From: Middletown Delaware
Are those #'s N/A or with N2O?? If N/A then I would think is a 90.
What is setup; Are they stock heads??
I'm sure someone can chime is on the bolt pattern of the tb, so u can tell which one u have.
What is setup; Are they stock heads??
I'm sure someone can chime is on the bolt pattern of the tb, so u can tell which one u have.
Instructor
Joined: Jan 2006
Posts: 214
Likes: 5
From: Middletown Delaware
Someone will give u the bolt pattern. I don't know them without looking. If no one chimes in I'll let you know when mine shows up this week.
Thread Starter
Le Mans Master
Joined: Feb 2001
Posts: 6,777
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From: West "By God" Virginia
CI 7-8-9-10 Veteran
Race Director
Joined: Sep 2005
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From: Pasco WA
To make it simple, the FAST 90 has 4 bolts attaching the TB, and the 78 only has 3. Another thing, if it has a 90TB, the actuator (the thingie that sticks out of your TB to the side) is flipped to the pass. side, because it doesn't clear the power steering resevoir. Also the gasket on a 90 is perfectly round, whereas, the 78 is square on top, and round at the bottom.
