i think i have a 350 in my 1971 lemans sport, how do I know for sure? Also, what would be the right size 4bbl to put on to replace the2bbl?
8 Answers
Check the block casting number. These are found on the driver's side of the engine, at the back of the head on the transmission mounting flange. You can use a mirror to see it.
http://outintheshop.com/faq/casting/castings2.html -- check casting number against this list.
there is also the engine it code on the front of the block just below the head on the passenger side . engine size should also be stamped on the side of the block near the motor mounts .
To address your 4 barrel question , if the engine is stock , leave it the way it is , you'll just spend more money in gas then anything else ! To put a 4 bbl you have to change the intake manifold . the carb doesn't need to be any bigger that a quadra jet , make sure it's made for that engine & not a chevy .
A prior owner already made the switch, I think the carb is bad and wasn't sure what is a correct size to replace with.
The 350 with automatic will run fine around 600-650 cfm with no other modifications. With 4 speed, cam, headers, and dual plane intake you can push 650-700.
A rochchesrter which is probably what you have now is the best carb for that engine , you can pick one up at a swap meet or on ebay make sure it a match for that engine . good luck
