305 into a 383?l

[75 Florida Roadster]

Ok motor heads, I need your expertise. I have a 75 vette and I want to put a 383 in it. I have a spare 305 engine in an 80 van and was thinking about making a 383. First it would be a learning process. I have never ground a block for clearencing of connecting rods, plus I don't want to have mega bucks in the engine. It will be used strictly for street. I am not worried about a 4 bolt main. Will a 383 crank work in this block? Has anyone ever used a 305 for starters? Is the bore smaller than a 350? if so, what would you come up with for cubic inches if you used it?
If I have to I will buy a crate 383 but you don't learn hands on that way. Thanks for your reply in advance.
Jack :crazy

 

[patsnitrovette]

you cant make a 383 out of a 305 ,a 305 with a 400 crank is a 331 ,335 or abouts,you would need a 4.030 bore and a 3.75 stroke to get a 383.they do have kits for 305 available,but they run out at higher rpms.

 

[75 Florida Roadster]

305

Thank You for the reply. I had a feeling the news wasn't going to be good. I think I am just going to dig deep in my pockets and go for a new 383 crate engine.

 

[Jack]

you cant make a 383 out of a 305 ,a 305 with a 400 crank is a 331 ,335 or abouts,you would need a 4.030 bore and a 3.75 stroke to get a 383.they do have kits for 305 available,but they run out at higher rpms.

I agree. 30 over 350 bore =4.030 ... 30 over 305 bore=3.766. You cannot overbore a 305 cylinder enough anyway ... you'll may be into the waterjackets by the time you get to 4.030 ... if you lucked out & didn't ... walls would be so thin you'd have early failure from hot spots/warping. Please don't bother stroking a 305. Plenty of buildable 350 blocks out there for cheap.
JACK:grinsanta