I need to put a new clutch / flywheel in, but I was considering doing a new motor at the same time because i have some major blowby. I have a 350 tpi that the PO told me came out of an 86 vette, and a t5 trans. Since everything is already set up for tpi I was wondering what blocks can I use with my tpi and t5 set up? Is this an easier / more affordable option than switching to carb? thanks

 

If it already runs with the tpi but just needs a new motor underneith the tpi then your options are either a 305, 350 or 400. They are all sbc's. Now depending on if that block is a 1pc rear main seal or not could change a few things. But in general those are your options. If it is a 1pc rear main seal block then your best bet would be to find a 305 or 350 that is a 1pc rear main seal block as well.
Edit: 1pc rear main seal=1986 and newer sbc's
2pc rear main seal=anything previous 1986 sbc's

 

Yea im thinking the blowby is from bad rings because i have good compression in all but cylinder 3 :/ . How can i tell if i have 1pc or 2pc? I guess i can look up the casting number but i dont know where to look lol

edit: i read that they changed to 1pc mid year 86. is this true?

 

Not sure on the whole mid year thing. Do you have center bolt valve covers? Im not to sure on if that will tell you if its a 1pc or not. But if they are then its a good possibility youve got a 1pc. The best sure fire way is to just get your casting number. But that is really hard to view with it in the car. Its on the back drivers side of the block along the flat spot that the tranny bellhousing bolts to. Do a search and im sure you will find more info to help with that.