i have recently found a place around town here that sells rebuilt th350 for around $225 ( although i plan on rebuilding it with higher performance stuff)so i was wondering if you guys think i should swap out my 700r4 for one? by the time im done with the motor i should be at about 445-500 hp and 405-450 ftlbs. i had already had my mind set on really beefing up the 700rf but if you guys think i would be better off with a th350 i plan to do the swap. i think it may also be cheaper/easier the build up the 350. it wont be a daily driver so i dont really care about gas. its more of a weekend/strip car. and also people are saying the b&m swap kit is better than the hurst so that would be the one i would use. any input/suggestions would be appreciated.

 

I just did the same thing. Either trans can be built up to hold the power.

If you decide to go the locally rebuilt TH350, I would check them out and find someone that has one in there car. I bought my rebuild kit from Dana at Probuilt. It was my first trans rebuild and it is working out great. It is also rated for 450-500 hp.

The Torque converters for the TH350 are cheaper than the 700R4.

I used the B&M torque arm bracket. It worked out ok. The biggest thing is getting the right bushing and bracket.

Hope this helps.

Oh yeah, you will need a different dip stick tube, maybe new trans lines, and of course you need to run a extra trans cooler.

 

- Either trans can be built for the power, but a 700r is a more expesive build.
Just remember that if you do go the route of the t350, you won't have as low of a first gear, so to maintain off the line performance you'll also need to change the rear-end gear.

 

yea thanxs, i planned on runnin 3:73 more than likely or what do you think a good rear gear would be.

 

Man you should be thrilled with 3.73's I had 3.23's with my th350 and it was quicker than my 700r4 through the 1/8th by about 3/10

 

awesome, just what i wanted to hear, yea alot of people recommended 3:73 since i would be driving it on the streets some too.

 

well i got another question for this post, what all would i have to do to have a th350 handle my motor hp/torque numbers without being thrown into the junkpile a couple months down the road.

 

You really wouldnt have to do a whole lot.

The TH-350 is pretty dang strong bone stock (alot more than the 700r4!)

My TH-350C was pulled from a JY many years back, the fluid was changed and thrown into the car. Since then its outlived the stock LG4 (the 305 that killed the 700r4) then lived through a pretty mild 350 and now its onto my latest creation of a 350, one rear end, a few sets of gears and a partidge in a pear tree. All with a JY th350c and a shift kit. Though rumor has it the 350C is slightly stronger than a regular Th350, this things been to hell and back and still goin strong.

I run without lockup and it hasnt seemed to hurt this thing one bit with the increased temps.


Unless your going to use really sticky tires and beat the snot out of it you shouldnt have to spend a whole lot to get that tranny ready for you.

 

IMHO, for racing, th350. Lighter unit(fewer gears), lighter rotating mass, closer gear ratios(as opposed to the granny low and the rpm drop from 1-2 and the od that won't engage at wot in the r4) and cheaper to mess with.

For street, 700R4. Decent low for quick takeoff, and overdrive.

 

84z28350 is right.
- For mild to moderate street car, a good rebuilt t350 will get the job done, no issues. Good clutch packs, a good "shift kit", and a decent converter are all you really need for around 500hp. They're great trans until you start going for large power numbers, then its time for a t400.

 

one more question which would be easier to swap the one with the longer or shorter tailshaft and also what is this i hear about the th350"c"

 

The TH-350C has the lockup function for the torque converter, just like a 700r4.

Theirs rumor that the tranny is also built slightly stronger thana regular th350.

The TH-350c is kindof like a 9bolt rear, good until you break it. then comes the joy of finding parts!

 

the long tail lets you reuse the old drive shaft. I replaced the stock torque arm with a Jegster that adjusts for pinion angle(the front mount sits in the driveshaft tunnel). they said it's good for about 400 hp.