Do they put more strain on the drive parts? 
Should I install a shift kit?
Thread Starter
Racer
Joined: Jul 2004
Posts: 420
Likes: 1
From: Lapeer MI
Should I install a shift kit?
I'm not 100 percent clear on their purpose. Here are the vitals...
Car: 1975 coupe
Engine: zz502 (stock)
Transmission: T400 (freshly rebuilt using stock parts)
Drivetrain: Upgrades include Spicer U-joints and carbon fiber half shafts
Rear end: Stock except for 3.90 gear (freshly rebuilt)
Tires: 275/40 R18 Nitto (traction rating AA)
Note: Other modifications made to the car should make it 200-300 pounds lighter.
2nd note: I plan to cruise the car on nice weekends but occasionally take the car to the strip.
A few car buddies are recommending I install a shift kit. I believe they make the car shift faster. Do they put less strain on the transmission by less clutch slippage? Do they put more strain on the drive parts? Will they make me more consistent at the drag strip? Thanks.
Car: 1975 coupe
Engine: zz502 (stock)
Transmission: T400 (freshly rebuilt using stock parts)
Drivetrain: Upgrades include Spicer U-joints and carbon fiber half shafts
Rear end: Stock except for 3.90 gear (freshly rebuilt)
Tires: 275/40 R18 Nitto (traction rating AA)
Note: Other modifications made to the car should make it 200-300 pounds lighter.
2nd note: I plan to cruise the car on nice weekends but occasionally take the car to the strip.
A few car buddies are recommending I install a shift kit. I believe they make the car shift faster. Do they put less strain on the transmission by less clutch slippage? Do they put more strain on the drive parts? Will they make me more consistent at the drag strip? Thanks.
Melting Slicks
Joined: Jul 2005
Posts: 2,545
Likes: 3
From: 406ci SB, AFR 180 Heads - 490 HP @5,600 RPM 529 lb-ft @ 4,100 RPM
The long soft shifts from the factory make for a cushy ride, but in reality they do more harm than good. The longer the shift takes, the longer the auto clutches are slipping. This creates heat and wears the clutches faster. A shift kit shifts by making them faster and firmer. This allows the clutches to engage faster and reduce wear and heat build up. The shift kit also improves lubrication. This puts more lub oil where it's needed most, again reducing heat & wear. A converter lockup kit is a shift kit to convert the "Pulsed Type" lockup to an "On-Off Type" lockup. From the factory the torque converter ramps up to full lockup, with periods of slippage in between. The lockup kit gets rid of this skippage by simply turning the converter on a certain point and eliminating heat from slippage. The converter produces 80% of all the heat a transmission makes, a lockup kit greatly reduces that. Also make sure you have a good transmission cooler. clean and infront of the rad.
Sorry for the long answer to your question, but I hope it helps you understand shift kits and their purpose. I'm sure others will be better with an explanation also
Sorry for the long answer to your question, but I hope it helps you understand shift kits and their purpose. I'm sure others will be better with an explanation also
Melting Slicks
Joined: Nov 2003
Posts: 2,362
Likes: 1
From: San Antonio TX
lol RatFinger hey some people can dream lol. But maybe he has a special Turbo 400.But the other things he brought up are correct. It will make the car a bit more consistant as well as improve the life of the trans with a shift kit. Also he is correct to use a good trans cooler. And yes it will be harder on the driveline as well.
Melting Slicks
Joined: Jul 2005
Posts: 2,545
Likes: 3
From: 406ci SB, AFR 180 Heads - 490 HP @5,600 RPM 529 lb-ft @ 4,100 RPM
Originally Posted by SHAKERATTLEROLL
lol RatFinger hey some people can dream lol. But maybe he has a special Turbo 400.
Sorry I missed the T400 in the post and was thinking T350 when I answered, but there are 400 shift kits.
Last edited by Glass Act; May 11, 2006 at 12:40 AM.
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Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
A turbo 400 with good kit and Trans Go shift kit will run 300k miles of hard heavy use without failure.....should, anyway, that that included in front of a Pontiac 455, good for 550 ft lbs.....
IF built correctly I think they good forever....
GENE
IF built correctly I think they good forever....
GENE
Pro
Joined: Jun 2005
Posts: 581
Likes: 60
From: USA
I used to be a die-hard manual-trans guy, until I got my first TH400 used car at a disposal auction, and put a B&M shift kit into it. chirped the tires at every shift, it was a blast. been a firm auto-trans believer since then, and have put B&M, Art Carr (the original), and TCI shift kits into TH350, TH400, TH700R4, TH2004R, and 4L80E, always pleased with the results. the only way to go. better mileage, reduced slippage, lower trans operating temp, extended durability.
Le Mans Master
Joined: Oct 2005
Posts: 6,247
Likes: 471
From: Glen Allen, VA
My 71 Cutlass I used to have had a shift kit in the turbo 350 and I loved it. As mentioned, it shifted pretty hard and would chirp the tires on the 1-2 shift. The engine was stock, so I never got it to chirp on the 2-3 shift, besides, it has 2.somehting gears and the 2-3 shift didn't happen until 90 with the throttle wide open.
Melting Slicks
Joined: Jul 2005
Posts: 2,545
Likes: 3
From: 406ci SB, AFR 180 Heads - 490 HP @5,600 RPM 529 lb-ft @ 4,100 RPM
Red_Shift, don't worry about the differential unless it's in poor shape, it will handle alot more than a simple shift kit add on. The C-3 has a very strong rear drive system. There are a lot of cars here pushing high HP with few complaints about breakage.
Melting Slicks
Joined: Jan 2006
Posts: 3,028
Likes: 2
From: North NJ
I'll "hold" onto your carbon fiber halfshafts and nice shiny crossdrilled rotors if your unsure about drivetrain stress. Don't want to hurt those pretty things. 
Go for the shift kit, you won't beleive the difference. Make sure your U-joints are in good shape and you should be fine. Only way your rear will go bad is if its already on its way out. If your yankin the trans, open up the diff and check the condition of the gears. Good luck.
Go for the shift kit, you won't beleive the difference. Make sure your U-joints are in good shape and you should be fine. Only way your rear will go bad is if its already on its way out. If your yankin the trans, open up the diff and check the condition of the gears. Good luck.
Safety Car
Joined: Oct 2004
Posts: 3,920
Likes: 731
From: Youngstown Ohio
Originally Posted by bozzman3
Ok, You guys have convinced me! Now which level of kit?B&M has two different stagesI have a warmed over 350 pushing about 330 at the flywheel in a 1980 L82.
Le Mans Master
Joined: Oct 2004
Posts: 5,269
Likes: 54
From: Orlando Florida
St. Jude Donor '05
I'm not 100% sure what exactly was done to my TH350. The pre-owner told me the tranny was "custom-build" with a modifed shift kit ... well... it shifts so hard that you get this neck snapping feeling everytime it shifts... OK, I'm not a wussie but too much is too much 
when I shift from 'park' to '3' with my foot on the brake it feels like the half shafts are about to penetrate the floor
If they offer stage 1 and stage 2 you might want to consider stage 1
when I shift from 'park' to '3' with my foot on the brake it feels like the half shafts are about to penetrate the floor If they offer stage 1 and stage 2 you might want to consider stage 1
Melting Slicks
Joined: Jul 2005
Posts: 2,545
Likes: 3
From: 406ci SB, AFR 180 Heads - 490 HP @5,600 RPM 529 lb-ft @ 4,100 RPM
Originally Posted by bams12
I bought the B& M shift improver kit but it has two different stages, Rv/Heavy duty and Street/strip. I assume that the Street/strip is the one that I will want . Any advice.
