Shift kit or not?

[lukecp]

I have had a B&M shift kit lying around for my TH350 for quite some time now. I love a nice hard shift into 2nd gear, with the accompying bark of the tires, but i don't know if i want to get the kit put in or not. I know they are pretty hard on tires, rear axles, and U-joints.
I just put all new U-joints and a carrier bearing in my truck, but the original 12 bolt rear proably has 400xxx miles on it. Will putting in a Stage 2 Street/Strip shift kit destroy my u-joints, tires, and rear axle much faster than just driving it around? My truck has a 3.07 ratio open rear if that matters.

[crazy longhorn]

I think every trans built should have a shift kit, & I have run both B&M & Trans go.......I prefer the transgo, as they arent as harsh at the lower rpms(normal cruise). They do shift very hard at high rpms when you need it tho. Good luck,crazyL

[Stocker]

Well, several years ago I put a B&M shift improver kit (I think that's what it was called) in my TH350. My truck only gets a few thousand miles a year, but I've had no problems. I like the firmer shifts and nothing has been damaged. Maybe if something was about to go out anyway, the kit may help speed up the failure. I'd say do it!

[lukecp]

Seems like 2 yes's for the shift kit so far . I love harsh shifts, but i was afraid it would be hard on parts.

Crazy L, where do i find a Trans Go shift kit? They aren't in my Jeg's catalog...

I was afraid the B&M would be a bit harsh when i am just driving around in "D", and i don't want the tires to break loose when the tranny shifts at around 1000-2500 or so RPM, but i would like a nice chirp above that, and a harsh shift when i shift around 5,000 rpm.

[crazy longhorn]

I have picked up the transgo kits locally, but Im not sure where to get them (its been a while). If you set the B&M up for RV mode, it shouldnt be too bad.....street /strip is pretty harsh tho(trans pac). crazyL

[lukecp]

I just found a Trans Go in Summit. They describe it as being pretty serious, and it says you can downshift the tranny into any gear at any speed, and hold it in any gear at any speed. I don't think that sounds like a great idea, i have accidently bumped the shifter into 1st on my truck when dropping it from D to 2nd to pass on the highway. Pulling 60 mph in first proably wouldn't be good for my motot, lol.

Think the RV mode in the B&M kit would at least bark the tires if i shifted around 4000 rpm or higher?

[1971 Cheyenne]

Can someone explain what exactly a shift kit does, and how you install one? I have absolutely no knowledge about these and would like to learn...

sorry if it's a dumb question


'71

[crazy longhorn]

the B&M transpacks have the same feature on downshifting, or holding gears......yes you do need to be carefull when set up like that! I saw a BB Olds spin 7600 for a second or 2(Oops). I had a transgo shift improver in the kids ranger(basic RV setup). It would lite 2nd up with no problem with a 305/350T , & a 3 to 1 rear gear. for most of the street apps, you really dont need a "full blown" kit. RV mode will have a firm shift, & the tighter you wind the eng, the firmer it gets. crazyL

[miket]

I have a hughes kit in my T400 behind my 502 running to a stock driveline (yuk) with new ujoints and the original ( 130 k miles) open diff 12 bolt.

I had one in my 67 shortbed behind a 383 and it would leave 2 nice short black marks going into second....it had a 12 bolt and a posi...never any issues and I drove the truck hard.


I was told by a "few" tranny shops that the Hughes parts are favorable.

[tom hand]

Well I can tell you from experience, that a stock GM cast second gear will not hold up to much tire "barking"...I have several paperweights out in the garage...lol. Anyone who builds trannys can fix you up with a second gear that will take all you can dish out and they are really cheap. (paid around $15 for the last one I bought) The problem is the trans has to come apart to put it in. If you want tire chirping shifts I would recomend having the shiftkit put in during a trans rebuild so the tranny guy can beef up a few nessissary parts on the inside the trans or you can do it about 6 months after you put the shift kit in.

[1971 Cheyenne]

ttt

[yellowgmc]

you could always add an msd ignition box with the rpm limiter to be safe in accidental 1st gear shifts. good excuse to buy more parts!

[smokekiki]

Cheyenne,the shift kits reroute and change the trans fluid flow and pressure.Automatics are built to keep the everyday person happy with a shift that slides into the next gear.The shift kits lets the trans go into the next gear with a firm shift.

[lukecp]

After reading the thread, i think i will go with the RV kit. My kit is the $29 B&M Shift Improver kit, not the transpack. My stock TH350 sometimes will chirp 'em going into 2nd, just once in a great while if i shift at about 5500rpm. It is a pretty fresh rebuild, so it should be OK for a while.

Thanks for the help!

[GloryHound]

Anytime you get slip in a mechanical system you change the wear of the system. A shift kit is going to wear out the parts of your drive terrain quicker but, the real question is how much quicker? This is mainly going to depend on how much torque your engine is producing. Also you start getting into a lot of torque with hard shifts another component that can give is the torque converter. I say go with a stick shift then you have complete control over how smooth the shift is or where in when you want to chirp.