adamcgodby

I have a 92 z28 original 305 car but has been swapped to a built 350. Had the trans (700r4) built to withstand 500hp and well it's not helped. I have had to have the trans rebuilt twice and its ready for a 3rd go round but I would honestly rather switch transmissions. I've decided to go to the TH400 trans and just want feed back as to what others have encountered doing this. I'm sure the cross member will need to be replaced or a new or fabricated. But what do I need to watch out for when buying one (I'm buying one that is professially rebuilt). Am I going to need a new driveshaft? Even though the stock shifter is for the 4speed can I still use it for the TH400? Do I need to watch out for spline count? I'm not worried about the speedo. I use a GPS. Any feed back is helpful, pictures and videos are great.

Thanks in advance.

adamcgodby

Or would it be easier to do a TH350 trans instead of TH400?

articwhiteZ

iTrader: (56)

the 700R4 when done right will hold upto 500hp all daylong. lingenfelter did mine back in the 90s when my car was done by them.
none lock up..

look up a better builder

with todays hardparts to put even more HP to the 700R4. the cost will be out of sight of most.
I just did one with 100% of the best hard parts you can get for the 700R4. just the hard parts came to $3500. then add a custom converter the way I want it was $800 (billet front) 9"
but then I want to Keep My overdrive and 4.56 gears.as the trans now has a close ratio gearing no more rpm drop when shifting from 1st to 2nd.. and 28" tall tires

Night rider327

iTrader: (13)

I have a th-400 in mine. I love it.
You will need a aftermarket Th-400 crossmember or make your own.
You will need a way to mount torque arm to trans tail.
When I 1st did my swap 12 years ago I used the old Hurst th-400 swap kit, since then I have went with an aftermarket torque arm that does not go to the trans.
You will need a 82/83 3 speed auto/4 speed man. driveshaft or a custom built one. (I part out third gens and have a couple of those driveshafts if you are interested)
You will need a th-400 slip yoke and a 3RN to 1310 conversion U joint.
You will need a th-350/400 torque converter.
Yes your stock shifter will work. From OD to 2 everything will be off by 1 on shifter...
OD will be D, D on shifter will be 2, and 2 on shifter will be 1.

adamcgodby

I've actually decided to go with the TH350. Due to the fact I can get a 9" tail shaft for it and it will be a 1/16" shorter than the 700r4. I believe I can use the same drive shaft considering there's only a 1/16" difference. And I found a crossmember on eBay for a 92 Camaro using a TH350. And the shift pattern like you said is what I was figuring it would read which is fine by me. Can someone specify what torque arm I will need? I'm ordering a 2200 stall converter. And the transmission I am looking at is a TH350 stage 2 from TCJ.

Night rider327 does that seem like everything I will need. I just need to know what torque arm I will need. And I'm not sure what hp/tq the car has. But the trans in ordering is rated for 550hp/tq.


The motor is a 91 block 350 bored 40 over flat top Pistons. With hydraulic roller cams for a circle track car. Not 100% what the lift/duration is. But it has vortec heads that have been ported and polished with a valve job and bigger springs. Has a Holley 650 double pumper 4barrel. 3.73 gears. The guy who built it use to build his own drag engines and circle track engines and estimated it from 380-460 hp. Once I get the trans taken care of it will be on the dyno for exact specs.

smh1987FFB

Did you have to modify the shifter cable bracket that mounts to the trans? I find that none of the bolt holes line up.

Night rider327

iTrader: (13)

Sorry, I can't answer that one. I used a B&M pro stick shifter, cable and bracket on mine.

Night rider327

iTrader: (13)

Yes you are correct on the driveshaft. Stock 700r4/T5 driveshaft will work on a th-350 long tail swap. We have a th-350 long shaft in my Dad's 82 firebird.

Torque arm depends on type of crossmember and setup you will be using. Please send link to that ebay crossmember.

My dad just wanted to keep the stock torque arm so he used the old B&M swap kit that has a plate that mounts to the tail housing of th-350 and then you use half of your stock torque arm clamshell and bolt that to the plate.

Th-350 has it's trans mount moved 2" so really you could just bolt or weld flat bar stock to a factory crossmember and make it work for a th-350.

The torque arm is the hardest part of it. If the crossmember you are buying has a torque arm mount on it or not is the big question before looking at what torque arm you need.

smh1987FFB

Your post said you used the stock shifter. I made it work by drilling a new hole. I will probably end up welding a tab on it to pick up another hole.

adamcgodby

The link for the crossmember is

http://m.ebay.com/itm?itemId=311567528077


The torque arm is the only thing I am hung up on now.

smh1987FFB

The UMI torque arm relocation kit as they call it comes with an arm to attach the torque arm bushing to. You need to buy an aftermarket bushing though. The P/N is 2232 and sells for $259.
http://umiperformance.com/catalog/in...roducts_id=300

adamcgodby

That was specified with the TH400. Ive decided to do a TH350 swap.

Night rider327

iTrader: (13)

No sir, my post to the OP said "yes you can use the stock shifter"

Night rider327

iTrader: (13)

If you want to go that route you will need this crossmember http://umiperformance.com/catalog/in...v28jclt1svmjk3

mrisley

Hello, I just came across this post. I am in Spokane as well. I was wondering who you had build your 700r4? I have a 72 Chevelle with a 496 and I am trying to get it to live.

articwhiteZ

iTrader: (56)

Louise Transmissions
tell them Jeff the white Camaro guy sent you..