Shift Kits?
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Joined: May 2010
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From: NC
Shift Kits?
I have been looking at some shift kits for my 75 auto' to make the shifts a little smoother when im being a little more liberal with the throttle. Do they make that much of a difference and can I get some other thoughts on them. A friend from school has a 66 falcon that is doing about 400 horses and he said that when he did the shift kit in his auto it made a big differance in his low end. any thoughts?
Le Mans Master
Joined: Oct 2006
Posts: 7,123
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From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
My personal favorite is Trans-Go. I've used their kits in GM's transmissions from the 125's used in the Citiations (remember those), all the way up to the 4L80E. Excellent luck with all of them.
Le Mans Master
Joined: Jan 2006
Posts: 9,192
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From: Boca Raton Florida
The trans go kit is one of the most popular shift kits and that might or might not be an indicator of Best or Better. I have used them in several transmisions and have always been satisfied. However, I might point out that the kit will not make it shift "Smoother" it will make the shift more "Positive" meaning it will slip less between shifts. That will inherently make it shift with a bit more of a bang that stock. Tranny temp and longivity will be much better under normal operating conditions than stock though.
Thread Starter
Advanced
Joined: May 2010
Posts: 54
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From: NC
The trans go kit is one of the most popular shift kits and that might or might not be an indicator of Best or Better. I have used them in several transmisions and have always been satisfied. However, I might point out that the kit will not make it shift "Smoother" it will make the shift more "Positive" meaning it will slip less between shifts. That will inherently make it shift with a bit more of a bang that stock. Tranny temp and longivity will be much better under normal operating conditions than stock though.
Safety Car
Joined: Oct 2000
Posts: 3,593
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From: Southern Indiana
I'll throw in a 3rd and 4th shift kit option!!!
I like B&M and if you could find a Hurst brand they are the best!!!
Anyway how about an easy project????
Your Modulator has an adjustable screw in where the rubber line hooks to.
You need one of those little pocket screw drivers that will fit in the end of the modulator and turn it in for later shifts and out for early shifts.
Now I heard only turn no more than 1 in or two out, but of course I have brought it out to the end of the tube but not the other way to the extreme.
I like B&M and if you could find a Hurst brand they are the best!!!
Anyway how about an easy project????
Your Modulator has an adjustable screw in where the rubber line hooks to.
You need one of those little pocket screw drivers that will fit in the end of the modulator and turn it in for later shifts and out for early shifts.
Now I heard only turn no more than 1 in or two out, but of course I have brought it out to the end of the tube but not the other way to the extreme.
Le Mans Master
Joined: Sep 2004
Posts: 5,116
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From: Livonia MI
I've done many of the B&M and Trans Go Kit's over the years, and smoother shifts isn't the description I'd use for any of these, as really designed to firm things up. I'm pretty much sold on the Trans Go's though, and install them in them all my auto tranny's. The B&M's seem to hit hard on the 1-2 upshift all the time, with the Trans Go's only hitting harder when getting on the gas. The TH350/400 installs a snap, but if doing a 700R4 kit, pack a lunch, maybe two. Keep in mind when doing these kit's, if running 100 mph, and accidently drop the lever into 1st, that's what you're getting, like right now.
Race Director
Joined: Jan 2007
Posts: 10,620
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From: Danville Illinois
2025 Corvette of the Year Finalist - Modified
2024 C3 of the Year Winner - Modified
2021 C3 of the Year Finalist - Modified
2019 C3 of Year Finalist (appearance mods)
Have had a B&M shift kit in my turbo 400 for over 30 years now, love it.
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From: Crossville TN
You won't get "smoother" shifts with a shift kit. You will get firmer shifts. If you have the stock THM-350 still in the car, I suspect your vacuum modulator has 'bit the dust'. It is a 'can'-like device mounted on the side of the transmission and will have a vacuum line going to it (from the intake manifold). If the line is loose, reattach it...that might fix the problem. If not, change the modulator and it will cause your shifts to occur sooner and smoother with light throttle.
