302 head 351 block

[Maleah]

can anyone tell me the benefits or drawbacks for putting 302 heads on 351 block?

 

[ForceFed70]

Depends on which 302 head you are installing.

If it's a stock head, depending on the year it may allow you to increase or decrease the compression ratio.

You would need to drill out the head bolt holes to accept the larger 351W head bolts (easy to do).

Ususally there is no advantage unless you managed to get a good deal on an aftermarket set of 302 heads.

 

[5.0ina66]

can anyone tell me the benefits or drawbacks for putting 302 heads on 351 block?

Yep, one problem, they wont fit. The head bolts are bigger on a 351W.

 

[rbohm]

advantages;

if you use the early 302 heads, then the compression ratio goes up.

disadvantages;

the 302 uses 7/16" head bolts the 351w uses 1/2"

the ports are smaller

the compression not only goes up, it can hit as high as 13:1

you will lose power overall unless the 351w you are building is a late 70's on engine, and then you step sideways power wise.