351 heads

[f8tlfiveo]

I am tossing around the idea of doing a 351 swap.. I have gt40p's on my 302 at the moment. Would these flow any better than a stock 351 head?Are there any decent ford production heads to put on a 351? I have searched and not been able to find much. I know putting 302 heads on a 351 will give you 302 power, just wasn't sure how good a stock 351 head would flow. If they are going to flow about the same I can just find a shortblock and use gt40p's for now.

 

[Jason 302]

I feel like a 351w with GT-40P heads won't be anything more than a stump puller that belongs in a truck. Not saying it wouldn't run well, just saying those extra cubes need to breath.

Personally I would save my pennies for a while and invest in some AFR 185's....then hang on

 

[f8tlfiveo]

Yeah.. I didn't really think it would be a performance upgrade.. I am going to turbo my car, so I figured I would start with a 351 block for more strength rather than buying a aftermarket 302 block.. Plus you get a couple extra cubes out of it.

 

[srtthis]

if i remember right the 351 heads flow ok but are somewhere around 72CC so they they dont make a lot of compression. which is what your looking for with a turbo

 

[f8tlfiveo]

Yeah definitely wanna keep it on the lower side..

 

[VibrantRedGT]

GT40p heads are ok for a 302 not a very good choice for a 351. Like mentioned AFR 185's are ideal, had these on my 347, just an excellent head. Look into a custom cam and 351 intake from TFS. With a turbo all this will really make some ponies.

 

[f8tlfiveo]

Is it easier to buy a newer roller motor rather than converting a old one to a roller?

 

[CarMichael Angelo]

You have to remember that stock 351w heads just plain suck. The last time I paid attention to stock 351w valve sizing, it was 1.85/1.54 I./E. Respectively.The exhaust port is tiny, shaped poorly, and full of cast iron warts and bumps. that was on a C9 or D0 "4bbl" head." later model smog heads were even worse.
I would imagine that the valve size has not increased since then. A gt40 head has what? A 1.9/1.6 valve size? Although that sounds like a stock 351 w head,. The port should be a little better though, and as a rusult should be a little better. As opposed to running vs not running ( since you have those heads already) I'd use what I had until I could afford a better head.

 

[f8tlfiveo]

My gt40p heads are 1.84 intake and 1.54 exhaust. I bought them redone with bigger exhaust valves. I would think that these would be better than a stock 351 head. And they only have about 2000 miles on them..can I run these heads on a non roller motor? I think I read a small base circle cam is needed.

 

[f8tlfiveo]

Is there a "budget head" that can be used without spending 1000$+ on a set of heads?

 

[Gearbanger 101]

Ported GT40's are't going to be ideal, but the'll get the job done. Remember, these were the same heads found on the '95 Cobra R and it made 300hp with very little effort.

 

[f8tlfiveo]

Ported GT40's are't going to be ideal, but the'll get the job done. Remember, these were the same heads found on the '95 Cobra R and it made 300hp with very little effort.

so if I ported the gt40p's I should be ok until I can get better heads.

 

[srtthis]

Ported GT40's are't going to be ideal, but the'll get the job done. Remember, these were the same heads found on the '95 Cobra R and it made 300hp with very little effort.

same heads as a 93-95 lightning also