so, a 305 LO3 motor is a 262ci, stroked with a 350ci crank....


What cubic inch displacement would you get if you used a 383 stroker crank in a 305 motor?

and... is it possible?

i'm going to guess 327, and no. lol

 

It's around 335 depending on the overbore. Waste of time and money, but you can do it and every fool with a 305 thinks it's a great idea to spend more money than a 383 costs to make less power than a 350. But all the parts are out there and people still build them.

https://www.thirdgen.org/forums/engi...ard-built.html

 

i agree, a waste of time & money. for the record, the 262 & 305 have different bores & strokes. 262, 3.671 bore, 3.100 stroke. 305, 3.736 bore, 3.484 stroke. a 305 block in standard bore with a 3.75 stroke crank will make 329 cubes. hardly worth the effort to end up with less than a 350.

 

Thanks guys, never said I wanted to do it, just trying to learn my bore n stroke combos lol.. u can buy a 350 block fo a few hundred bucks, machine shop would cost a thousand lol...

But, I guess mainly, I'm trying to figure out why people don't bore their 305's out a 4" bore, and change to 350 heads, etc etc.

Not saying its cost effective either, but, if u buy a 350 used, first thing u do is get it machined, why not machine the 305 for a larger bore?

Again.... strictly infomational purposes only.... and ignore the money part of the equation...

 

Because you can't.

 

i actually got the answer i was looking for on yahoo answers lol...

"The 305 and 350 is NOT the same block and you can NOT bore a 305 out to a 350.

The outside of block is the same, cam bore is same, etc but cylinder bore and walls are not.

BTW 305 is not a 262 block eaither. It (262) has an even smaller bore at 3.671

The 350 has a 4.000" bore
The 305 has a 3.735" bore

Max over bore is .060" and truthfully about half of the blocks don't have enough wall thickness to go past .040". After .030" over you should have all small block engines sonic tested to see if theres enough wall thickness

Even with the max over bore of .060" on a 305 that gives you a 3.795" bore, still .205" away from 4.000" (almost 1/4 inch)

That's a 314.9 cid engine.

The bore size is the prob with the 305. That tiny bore can't breath good as RPM comes up. The small bore acts as a bottle neck and choke point"
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as far as i'm concerned THAT is why people who know these things don't build 305's up inherently.

makes perfect sense, and is a very good answer... now i know!