Fast 90 Help
Thread Starter
Instructor
Joined: Jun 2006
Posts: 223
Likes: 0
From: long island N.Y.
Fast 90 Help
i currently have a ls6 intake on my01. i have heads and cam producing over 400 rwhp. im looking for another bump in hp. is it worth it and advisable to go with the fast 90 setup. For the money would it really be noticeable. I am thinking about running it with NOS
My other thinking is possibly do the gears instead.
All ideas and input would be appreciated
My other thinking is possibly do the gears instead.
All ideas and input would be appreciated
Burning Brakes
Joined: Jul 2006
Posts: 968
Likes: 12
From: Regina Sask
I gained 25 RWHP over the stock LS6 manifold/ported 80mm BBK TB, with the Mamofied 90/90 intake. Tony includes the better intake seals & adds thread inserts for the TB. My car went from 409 RWHP to 434 RWHP with the FAST intake swap (I just finished swapping the LG G5X3 114 LSA camshaft in place of the very weak 229/242/.630/.630/114 LSA brand X camshaft, and will be getting back on the Dyno Jet in a few months).
I painted the intake manifold with Krylon high heat paint & trimmed the fuel rail covers.
Russ Kemp
I painted the intake manifold with Krylon high heat paint & trimmed the fuel rail covers.
Russ Kemp
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Since your original question was a choice between gears and the intake, personally I would choose the gears over the intake. The gears not only give you a bump in acceleration but if you install something like the DTE differential, you can bolster the strength of the differential for the power level you are currently making with the car. I suspect that if you are like most of us, you will be back later looking at the intake 
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Burning Brakes
Joined: Jan 2002
Posts: 885
Likes: 0
From: The Woodlands Texas
The FAST intake and LS2 throttle will not be of much use until you go to a heads / cam swap and start making at least 380 or 390 hp. You just don't need the air/fuel equipment until then.
I agree that a 3.73 or 3.90 or so rear gear is a better bang for the buck if you are basically stock.
I agree that a 3.73 or 3.90 or so rear gear is a better bang for the buck if you are basically stock.
Burning Brakes
Joined: Jul 2006
Posts: 968
Likes: 12
From: Regina Sask
Yes, but 2001blkvette stated that he has cam & heads and is making over 400 RWHP. If his car has 3.15 gears, installing 3.73 or 3.90 gears will then require drag radials. And if he is going to install a nitrous kit, 1st gear will be useless!
When I swapped 3.73 gears in place of the 3.23 gears in a high 12 sec 1991 Trans Am GTA that I used to own, the car never went any quicker or faster in the 1/4 mile. The car was harder to hook up, and just revved too high at highway speeds. I wished I would of left the stock 3.23 gears in the car.
If the car has 2.73 gears, a 3.42 would be a cost effective upgrade, and would be 2400 rpm @ 78 mph. With 3.73 gears the rpms would be 2600 rpm @78 mph, and would be almost 2800 rpm @ 78 mph with 3.90 gears.
Russ Kemp
When I swapped 3.73 gears in place of the 3.23 gears in a high 12 sec 1991 Trans Am GTA that I used to own, the car never went any quicker or faster in the 1/4 mile. The car was harder to hook up, and just revved too high at highway speeds. I wished I would of left the stock 3.23 gears in the car.
If the car has 2.73 gears, a 3.42 would be a cost effective upgrade, and would be 2400 rpm @ 78 mph. With 3.73 gears the rpms would be 2600 rpm @78 mph, and would be almost 2800 rpm @ 78 mph with 3.90 gears.
Russ Kemp
Burning Brakes
Joined: Jul 2006
Posts: 968
Likes: 12
From: Regina Sask
If your going to be using street tires (no drag radials), and if the tires spin off the line now, changing gears will make it easier to spin the tires. And you have to consider the highway RPM. With your 3.15 gears, the RPM's will be close to 2200 @78 mph.
Since the 3.42 gears are stock on the 6 spd cars, you may be able to get a used complete rear end for a good price. Depending on the size of your cam, you may need a higher stall TC more than a gear change.
Russ Kemp
Since the 3.42 gears are stock on the 6 spd cars, you may be able to get a used complete rear end for a good price. Depending on the size of your cam, you may need a higher stall TC more than a gear change.
Russ Kemp
Thread Starter
Instructor
Joined: Jun 2006
Posts: 223
Likes: 0
From: long island N.Y.
my cam is the tsp 228r 114lsa. so it might make more sense to keep the gears, get the t/c and maybe fast 90.
would the 3.15 work well with the 2800 stall, or is it better to get the gears done, even though i would most likely only go to a 3.42 rear
would the 3.15 work well with the 2800 stall, or is it better to get the gears done, even though i would most likely only go to a 3.42 rear