400 sbc
 

well i bought an 1985 Iroc-Z with a 400 sbc, Turbo 350 but no title, so i was thinking of swapping the engine into my 89 RS. Is this a good move, or is the 350 a better investment, it's going to be a daily driver only but with some kick in it to keep the ricers at bay. My only concern is my t-5, can it support its power and is the swap even worth it, i have a 305 in it right now? Thank you

RE: 400 sbc
 

do you know what your rear end ratio is?

RE: 400 sbc
 

its all in what your wanting. 400's are known for their torque. But honestly, if your going to keep this your DD, keep with the 350

RE: 400 sbc
 

Just FYI the 400 small block is an externally balanced engine so the flywheel and harmonic balancer have to be for a 400,you can't use the flywheel off the 305 or a 350 with that engine.
Other than that it should be a plug & play,just get the right flywheel and harmonic balancer.

RE: 400 sbc
 

My built 400 makes over 500hp and 500 ft lbs, it is internally balanced now but it is a very extensive build.

RE: 400 sbc
 

T-5 was not offered with the 350 because it could not handle the torque. Compaired to the 350 the 400 is a torque monster. the 400/350 combo can be a good match if the 350 has been beefed up.Many of the SB 400 came with TH400 from the factory.

RE: 400 sbc
 

I'd really prefer to keep the car a manual transmission cause its a whole lot more fun and for that little extra fuel mileage. What about a t-56 swap or maybe rebuilding the t-5? Also has anyone heard of a 400 sbc with a tpi unit. I have TBI on the 305 right now and carb on the 400 and a 400 TBI doesnt interest me AT ALL, what would you guys do?

RE: 400 sbc
 

i think i read somewhere its the design of the t-5 that makes it weak. not the gears. but dont quote me on that. i think your best bet would be the t-56 swap.

RE: 400 sbc
 

i like the 400 sbc but people tell me they have really thin cylinder walls. so they can do damage if they happen to overheat. just a heads up.

RE: 400 sbc
 

I have heard that as well, so if you are interested, you can do like what I am doing and using the 400 pistons and crank to make a wicked 383 stroker witha 350 4 bolt main block. just a suggestion. I know some here will pont out you could buy one for less headachs that cost about 5 grand ( and it do look sweet), but something about the " ya I built it myself" thing I kinda like.lol.