hi i have an 86 trans am with a 350 in it i am rebuilding the motor with new pistons rods etc. during the winter i would like to put a turbo in, i have 1 that i got from the junkyard it is a garret T3 from an old chrysler 4 cycl, i think it is a .46 trim im not sure.Is this turbo to small? also do i need to have a cross over pipe? because i just want to flip some headers upside down, weld a flange on it and put a downpipe, is that ok?

 

Good winter project. With a turbo that small you need twins. Get one more just like it. It is probably the popular .42 A/R comp. housing (40/45 trim) unit. Make sure you beef up the flipped headers for street use. They will spool fast and be good for 350 - 400 FWHP.

Beyond that, all you need is downpipes, oil feed and return lines and a way to fuel it. This power adder board has many examples of how to do it. Search for "oil return", "downpipe", "749", and "FMU" and you should be all set.

EDIT: With those small turbos it will have all kinds of torque down low, but run out of wind when you rev it up. If you want a high RPM / high HP setup, you would need to find bigger turbos. If they are 50 trim compressors it would be much better. Pull the compressor housing off and measure the compressor wheel and compare the wheel size to the sizes at majestic turbo (website). They have the wheel size and compressor maps.

 

yes but if i was to just get a bigger turbo would i need a cross over pipe? because that means i would have to do more fabrication.

 

With those turbos you would need twins. There would be no cross over pipe, but the work doubles because of the two turbos and two downpipes. Two of everything.
I have a twin setup, but if I was to do it over again I would have went with one big single due to simplicity and ease of maintence and fabrication. Performance wise I am not stuck on singles or twins. I like cheap, reliable, and simple. That is why I like the single setups better. Some like twins.

EDIT: Fabbing a cross over pipe out of 16 ga. is more simple than fabbing two downpipes, two intake pipes, two oil feed & return lines. Not to mention cost of all that stuff.

EDIT AGAIN: Is that turbo water-cooled also? If so, then you need to make all those water feed & return lines. It took quite some time to make that stuff on my setup. Custom 3/8" Y-fittings, 3/8" lines, NPT fittings at the turbos, finding 18mm copper washers, 3/8" silicone/water-hose, etc.
Search for "another twin turbo Camaro" and you will get a complete part list.