Will a 4" crank fit in a 305?

 

If by 4" you mean the stroke, no, at least not logically.

2" (for the distance from the crank centerline to the rod journal) + 6" (connecting rod) + x (piston height) = 9.xxx deck height

Where "x" equals the piston height. You would need about a 1" compression height for a piston. Good like finding that for a good price. Also, the clearancing needed is a bit much.

Why would you even want a 4" stroke in a 305. Cost vs. output, the 305 is CLEARLY lacking versus the 350 block.

 

probaly because its way out of the ordnary and i want my car to have the orignal block it but it would be different. more powerful than a 335 or a 340. just trying to keep the same block. also i have a concerns about california smog and i know there is no law about substution for cubic inches. thanks for your help though.

 

What is the budget for this project.

Keep in mind, pistons alone will be $600+ probably.

Oh yea, unless they check casting numbers and cross reference to the VIN, look at the outside of a 350. Then look at the outside of a 305. There is no difference.

 

There are special blocks designed to fit a 4" stroke. They have a raised camshaft for extra clearance and the oil pan rails are located further apart.
I guess some guys have used 4" stroke cranks in factory 350 blocks, but I wouldn't want to try it, cause it would be a very labor intensive project. Same thing for a 305 block.

 

about 3500 and i just want to redo the bottom of the engine cause i already have edelbrock heads,intake,runners,and chip done to the car. but it sounds like it might have too much labor involved even though i pulling the engine myself.

 

you'd be ahead to pull the engine if you're that worried about the numbers matching and buy a 350 block, or even a 400. reguardless it'll take a lot of specalized pieces to make a 4" stroke work in a SBC.

 

Does anybody have pics of a 4" crank SBC? How about pics of the clearancing?