how much horsepower will a stock tranny with a shift kit handle

thinking of installing a shift kit and running the edge comp hot
and later adding a single disk converter what do u guys think will tranny hold up
not alot of racing is my daily driver maybe run a couple of times on the track and dyno looking for 350-375 hp

thanks

 

Depending on mileage and trans condition, it could end up killing the trans.

Do it once, do it right. Shift kits are a bandaid.

Dave

 

thanks

130000 highway miles

so go with a aftermarket valve body

 

a shift kit does the same thing as an aftermarket valve body. you could do the shift kit alone but when i had my tranny built, I put new clutches and seals in along with a billet single disc converter. It holds up fine for me although I want to get a tripple disc down the road. A valve body and coverter should work fine as long as you dont slip your tranny on a regular basis now.

 

I have a Transgo shift "reprogramming" kit installed and really like it. I have also added about 35 extra horsepower and that is about all the stock transmission will take.

Gotta love 1960's technology...

 

This is: Not True

 

Actually, it is.

Unless a valve body is then out onto a machine and it is setup correctly, shift kits often create far more issues than they solve.

Dave

 

That is simply a false statement.

I suspect you are speaking of someone that trys installing a shift kit in a burned up trans that needed to be completely rebuilt in the first place

 

No. It is correct.

I can draw the distinction of a shift timing change and one that alters internal VB pressures.

Many of these kits alter the pressure flow and timing internally. Many allow for simultaneous application of internal elements and or poor timing resulting on flare and low pressure issues.

This is not my opinion. This is a fact. Yes, I have seen many transmissions wiped out due to shift kits. And that could have been avoided by simply checking the VB out on a machine and tweaking the setup.

Many guys defend shift kits because "they have never had a problem". Then they can't understand why they have poor shifts, hard shifts, flare, ect after a local trans guy told them they cold hold another 100HP with no problem. This is no surprise to those of us that have been around transmissions before owning a Dodge.

But I will no longer argue the point. Guys want to believe what's printed on a package, not what is based in reality.

Dave

 

a shift kit allows you to choose how hard you want your shifts... someone that wants the hardest shift they can get without knowing the consequences would surely damage any transmission. Can you explain what a bought valve body has that a shift kit doesnt? I do believe companies require a return of a core so they can drill the same holes and change the same springs as a shift kit changes. There can even be variances in what specs company A does compared to company B... which one is "done right"? Not trying to be a DB but IMO, a little common sense and a shift kit can do everything if not more than a store bought valve body.

 

thanks guys for the info just trying to find the best way to go
what do u think of dunrite valvebody or who do u recommend

thanks

 

I had 134,000 miles when i put the transgo shift kit in. It helped the shifts and helped with the comp, but couldn't hold after the injectors. Dave Goerend built a vb & TC for my truck. I'd say call Dave and spend the $$, you be happy you did. Then you will be a step closer when you need a rebuild.

 

Dunrite builds a really nice vb.

 

I had an 06 i put just a transgo shiftkit in and it worked wonders. Finally after running crazylarry, 120hp injectors, dual fueler, fass 150, mp8, and 180 shot of nos the input shaft broke. All the internals were golden just the shaft sheered off. I just put the reprogramming kit in my 47re and all i can say is wow. My tranny has 109,000 on it and i put this kit in and it is awesome. All i have is 90hp injectors, fuel plate ground and slid so far but there is no slippage and boy does she grab. Just my stupid opinion, sure you can waste the extra 400 dollars or so and get a valve body that does the same thing.

 

Nothing wrong with a transgo shift kit. They are great for the money.

I bought my truck with a fuel plate, and a slipping, clogged up filtered transmission at 163,000 miles. The transmission had been replaced before, but i dont know how many miles the transmission had on it when i bought it. I assumed it must of had 30-40k since it needed a filter change pretty bad. I drove it a little, and then changed the fluid/filter, and put the transgo shift kit in. It was slipping before, and after i did the transgo/filter change, It held good. Then i added a 4k GSK. It still held good, and pulled much harder in the fluid coupling. Somewhere down the road from there, I ended up with a triple disc and valve body from goerend, along with a billet input and suncoast flexplate. I would guess im making around 360hp now. The transmission still has the stock clutches, and seals in it and is still doing great. The truck now has 238k miles on it. Almost 80k miles later after my "band aid's". I also pull trailers plenty in the summer, and have mader several drag strip passes, and pulled it several times too. As long as you are working with a transmission with decent clutches, a shift kit can only help if its installed correctly. That and a good converter makes a huge difference. I still cant believe how good my transmission has been.

Eric