danltr450

I am in the process of finishing my 351w project that I was going to can. I am at the part of the heads, I now have a set of p heads that have the bowls cleaned and smoothed. the exhaust is opend up to the larger felpro gasket and the intake is matched to the 1250 felpro. does any one think these heads are to small or will the be sufficent. I can get my hands on a set of un ported gt40 heads off a cobra for $400. As for the rest of my set up I have a f cam , perfomer rpm air gap and a stock 89 truck bottom end with low miles and fresh rings bearings etc.

ZachW04Stang

Its probably time to upgrade to some aftermarket heads. GT40ps flow better then gt40s from cobras. The problem is both heads are really gonna choke a 351. Its time to get a head that will get some air into your 351.

my77stang

i'd throw the P's on and drive it. they arent as good as $1000 heads from trick flow, afr, etc - but you already have them AND they have port work done. they are more than enough head for a mild 351w.

danltr450

would a valve job be a noticeable increase in power? (3 angel valve job )I have been told both ways that it will and it won't, but never had a set of heads then had a valve job doen then put them back on to see the difference. I also just noticed that patriot has a new head and ifI were to save a little money to buy a set I would probably go with them. I am more or less looking to see what kind of power I will gain with this head.

my77stang

dude a valve job will do nothing other than make sure the valves are sealing (if they arent, your loosing power) but seeing as how they are GT40 P's and they have port work done to make them flow even better...... you have a GOOD set of heads already. not the best, but a GOOD set of heads. use em, and spend the other 1,000 your saving on other parts to make your car perform better.

stang8689

might as well use them then get some better ones down the road

danltr450

Good point, you guys are very convincing. glad you dont know my wife. She would use you to get what she wants from me. With my intake set up should I use a spacer between the carb that is open or one with the 4 holes. doe s either one creat more top end than the other?

danltr450

http://www.thatmetalbox.com/automoti..._head_flow.pdf

how accurate does every one think this is. if its close these heads should do pretty good

my77stang

the heads will flow fine, and as for the carb spacer a 4 hole adds a little more to the bottom, while a open adds more to the top.

ih8chevy

correct me if I am wrong but arent the 69-70 351 heads basically the same as gt40 heads? So why would it be much of a problem if they have port work. My question is why would you put an F cam in that thing? Thats gonne be the weak point.