do i need short or long tail piece ? ive got the chance for a th350 been rebuilt for 200 . im putting it behind a 5.3 stage 2 turbo cam an a 7875 turbo . expecting 5-600 hp

 

A "rebuilt" th350 is not the best option at that power level. You need a well built trans to hold up and honestly if you plan to do much more than drag race the car, I'd keep the overdrive.

 

Th400 no question

 

TH400 is heavier, and will hold more power

TH350 , you will need a long tail shaft to swap it in without changing driveshafts.
You'll need more money to hold the same power as a th400

I had a th350, built with decent parts and it held fine to high 10's in my 3500lb car.

 

On a TH350:
The extension housing length has to match the output shaft.
Complete disassembly is needed to replace the output shaft.

If it is a 9" length extension housing model and Chevy bellhousing bolt pattern, it fits once you adapt the torque arm mount and line up the mount.
But, you lose OD.

Outside that, cost and complexity pile up to negate your perceived savings.

 

I would not try to run 500 HP through a TH350.

 

500-600 whp is realistic on that turbo. Thats alot of power and torque. You will want the th400 durability and converter spec’d for turbo which is well known for that combo by most major converter companies like PTC, pro torque, circle d etc

 

i been study for a couple years an this combo seems to be the ticket for what i want .5-600 whp 10 sec. car .im just hoping the summit stage 2 turbo cam is a good fit for the combo .i was gonna do the btr stage 2 but summit specs are pretty close an 130 dollars cheaper .

 

Yeah its plenty of cam and will work. The ls is pretty tolerant of a variety of cam specs lol they all seem to work

 

what stall would you use . summit is recommending at least a 2800 . im thinking sumwhere around 3000 but im not sure . the cars gonna be street driving a good bit but not a daily driver .

 

Depends how you want it to behave and how soon it spools. If you dont have a transbrake for boosted launches at the track then may like more stall speed to get into boost sooner. That thing should be coming on pretty strong by 3000-3200 anyway so i would probably be in that range for stall speed, 3200-3400. Maybe even 3600. A tight converter can make turbo lag worse but too much makes it on off switch lol

 

im thinking about a tranny with a transbrake . i wanna be able to drive it outta boost whgen normal driving . but when i nail it i want boost to come on quick .that turbo should be full spooled at 3300 so ive been told an that cam is good for 2800-7000 . so if i go with a 2800 converter will that give me the type of driving i want to do ?

 

It possibly will. I’d still lean toward 3000-3200 atleast but spec’ing out a turbo converter is tricky because stall changes with torque which you control by boost lol to a degree that converter will act loser with more boost if it can build that boost sooner. But like I mentioned a good converter company will know what to do

it will be out of boost in normal throttle. Heavy part throttle might get close to 1-2 psi lol not a bad thing. But yeah it should light up quick on wot stab either way.

 

I agree 100 percent.

Ptc from my experience is very very good at custom turbo build converters. I recommend them. Always nailed mine right on. I had turbo v6s which were even more difficult imo to get right.

 

thanks guys ill give ptc a call after i get the cam put in . i should get all the parts for the cam instal in june an get the engine in in the end of june begining of july .

 

ok i got the summit stage 2 turbo cam also went with a ebay gt45 price was cheap enough
. i got a good deal on a th350 it held behind a 4.8 with a stage 4 cam a 200 shot of juice . if it dont last no big deal . i got it fur 150 . i think im going with a 3200 - 3600 stall . i watched videos on youtube .it looks like you can drive easy . but if you get on it it stalls . that will be good i hope any imput would be nice .

 

ok ive gotten a better job an am thinking about buying either a th400 or a powerglide .im leaning toward the glide . whats your all thoughts

 

I think you would be money ahead with a TH400. powerglide can work with a ton of stall speed but the TH400 would still likely be quicker.

 

if you think you may ever want to do something other than drag race it, put a 400 in it

 

thanks guys for the input