454 big block and a 350 turbo transmission?

Question

i have a 76 chevy that i dropped in a 454 BB but the torque converter doesn't bolt up to the flywheel and it has a 350 turbo transmission. the motor that was in it before was a 350 SB but im going to get a torque converter for the 454 but i was wondering if the transmission would have to be change too or will it work with the 454? I heard that the motor would shred the transmission almost right away, but the source is not that reliable.

Answer 1

If your motor is all stock the trb 350 should do all right as long as your not driving like a maniac. Now if your making 450 hp or more you may need to upgrade. Summit, Jeggs, TCI, and bowtieoverdrives.com all have what you need. I would probally switch to a 700-r4 you'll get a little bit better fuel mileage, more top end, and reduced engine wear.

Answer 2

I did a 454 big block transfer into an 89 GMC safari mini van. I have the 700r4 tranny with the same problem could not bolt the torque converter to the 454 flex plate. To fix the problem I used a flex plate for a 72 chevelle 454 and my tranny bolted right up with no problem. the only problem I had was the torque converter will not hold the kinda torque ( mine being from a v6 converter) it messed up the fins in the converter so had to get a heavier converter to handle the tork of the big block. Your 454 will generate more torque then a small block could be the only problem I could possibly see.

Answer 3

350 Turbo

Answer 4

If you are going to change the trans. (no real need to) stay away from TCI!!!!!!!! I have bought 5 of their so-called performance transmissions and they all came apart. They only build junk on an assembly line that can't take the horsepower they claim. (I was 100hp under the rating) Their 700's are a joke. If you want a good custom built trans. Go to ATI in Baltimore, MD. They are on the web and do a much better job for about the same money. If you are going to keep your trans. (not a problem) you will need to change the flexplate NOT the converter. Also check on the motor balancing.(internally or externally) and use the appropriate flexplate. You do not have to change the trans or the converter(unless you want a higher stall speed)

Answer 5

A TH350 doesn't sound like it would be enough to handle a mudding 454. I still think that for $500, all of that is OK (depending on the shape it's in) but I wouldn't count on that 350 lasting too long.

Answer 6

If the turbo 350 is in good shape you should not have a problem if its a stock 454...Granted the tb400 is a little stronger . Make sure you use an externally balanced flex plate with the 454 engine..

Answer 7

I have a Turbo350 behind my built 468 BB, moderate cam,Holley 770,headers,March pulleys,TCI rattler balancer,ect.It's been back there for 4 years now and still works flawlessly.Ihad it rebuilt with TCI Maximizer kit from the beginning and TCI Breakaway torque conv,very stout trans.Its in a 71 chevy 4x4 with 36 inch Swampers and detroit limited slips front/back

Answer 8

i doubt it would even bolt up and the 454 would for sure destroy a 350 turbo trans.

Answer 9

You will have to get a different torque converter, but judging by the fact that you put a rat motor in i am assuming you are going for horsepower and performance GET THE TRANSMISSION BUILT if not you will be back in it real quick.

Answer 10

no UN true 350 is a fine transmission, people that said that are UN educated guessers you will be fine, many GM hypo cars came with big blocks and turbo 350's nothing new