blownfiveo17

Ok so im having to rebuild my car and i might as well take advantage of it. I am deciding if i should go with a 347 or a 306. What do you guys think. I have a couple questions about the two. first with the 347 would i need to change my heads? can i just bolt the stock ones back on? any dangers if i did? Witht the 306 i have the same question can i just put the stock heads back on?

Thanks.

USMC1775

Both you technically COULD use the stock heads, it would kill a 347 though, moreso than the 306. A 306 is essentially a rebuilt 302, while a 347 has more stroke and much more power. Id say if its an option, go with the stroker

If you cant afford better heads, go with the 306.

5ohhh

With the 347 your going to need more head to run some rpm's. with the 306 your not going to gain any power with stock heads.

blownfiveo17

By kill the 347 do u mean restriction of power or damage? my main concern is damaging my engine or any parts by using the stock heads. I mean would anything be damaged if i ran it with stock heads?

mjr46

meaning choke it!!!!! what's the sense having a 347 if your pals honda down the street will still crack your a**

SonicBlueFiveSlow

No sense running stock heads on a 347, what good are those extra cubic inches if you can't let them breathe. Also, a 306 isn't really a performance thing, it's to get fresh cylinder wall surfaces.

kweb288

ive seen some pretty wicked 306's.... they can/are performance engines, its just more people go for the cubes

Portmaster

It won't damage your engine if thats what you are asking. It will be better suited to plow a field than power a performace car though. The engine won't be able to get enough air so with the stock heads it's going to prob run out of breath around 4500 rpm. If you cant upgrade the heads go with the 306 and a very mild cam

Alex-7

If you're able to, get a 347. Run it with the stock heads, then next time you run into some cash upgrade them and it'll be like bolting on 200hp!!! ha!

SonicBlueFiveSlow

Well I meant if the only thing done to the motor is being bored .030 over, you're not going to notice a huge difference with those 4 more cubic inches.