I need to know if i can upgrade my 305 to a 383. will i have to change my set up to carb or can i keep it as TPI? my Camaro has the LB9 block

 

No, can't be done. The 305 bore is 3.736", a 383 is a 327/350 block with a 4.000" bore which has been overbored to 4.030". With the 3.75" stroke, that comes out to 383 cubic inches.

If you put a 3.75" stroke crank in a 0.030"-over 305, you come up with 334 cubic inches. Before you ask about that, read https://www.thirdgen.org/forums/faq-...5-stroker.html .

The most you can safely bore the typical 305 block is .060". 3.736" + 0.060" = 3.796" - well short of 4.030".

You can keep TPI with a 383, but it will be very restricted. You can upgrade the TPI hardware to handle it. But, emissions legality will become a problem with the "better" TPI upgrade hardware. The only emissions legal carb is the factory computer controlled type.

 

My suggestion, if you have the resources, drop in a 350. If will bolt straight in, and you can build it to a 383 from there.