How much horse approx would a 305 with forged pistons bore over a decent amount,also forged rods,a mild cam,no bolt-ons or anthing like that and its carberated, the motors all stock besides internal, all external stock how much horse would it be making?

 

Slightly less than stock.

 

how would it be less then stock, a stock what?

 

Exactly.

You haven't got nearly enough info in there to compare with anything.

 

im asking how much horse will it have approxemently with the internal built but the external is not, heads are stock,headers are stock everything besides internal how much horse approx will it have as it stands with no external engine parts , its a chevy 305 from the mid 70's recently rebuilt.

 

Well stock cams can be considered "mild", so without actual cam specs no power gain could be estimated there. You haven't said if there's any compression change with the new pistons, so no power gain there either.

You did say that the pistons are forged though, which means they're probably heavier than stock so the increase in reciprocating mass would suggest that the engine would make less power than it did before the rebuild, all other things equal.

 

gotcha so some boltons should boost it right like intake, carb,headers ext.?

 

Intake and carb will get you next to nothing. Headers and exhaust will show some benefit though.

In general, good power comes from good heads (which any heads from the 70s most likely are not). Matching the cam to the heads ensures you've got a good powerband. The rest of the parts don't generally make you more power, they only cost you less.

 

Well stated Apeiron.

The bottom end doesn't give you any power, so all the nice rotating parts only add durability, no HP. You'll need good flowing heads and a well suited cam to peg the HP number higher on the dyno.

'70's 305 heads are notorious for being crap. I think the '70's 305s were rated at or around 145HP. My '82 LG4 was 145HP, so I can only imagine a 70's one as being worse. So with your modifications, we can say around 125-130HP. Got beaten badly by any toyota echo's or anything yet?

Throw the roots blower on, or the 250HP nitrous shot and you'll be set

 

not gunna waste time and money i will just throw it in while i build a 350 ha thanks guys