351w heads?

[SMOKEDYA]

So i have a set of GT40P heads ported and a set of stock NON ported 351W heads. Which heads will work better on a 40 over 351? As far as i know the cam is stock and the intake will mopstlikly be a TFS R or lightning? peace




john

 

[enyawix]

use the GT40P if you spark plugs will clear the headers.

 

[squeak93]

Yes, u may have to modify the headers to clear but the p heads are tons better..even when both are ported....Unless u have a set of 69 or 70 heads.

 

[SMOKEDYA]

as far as i know the 351 heads are 74. thanks peace



john

 

[Brandon11010]

yea you want 70,71 351w heads for them to be any better than stock 302's.. i have a set of 70w heads on my 302, ported, larger valves.. made 344 horse 360 torque on the engine dyno with those and a b-303 cam..

 

[SMOKEDYA]

Yes, u may have to modify the headers to clear but the p heads are tons better..even when both are ported....Unless u have a set of 69 or 70 heads.

why would i have to modifiy the headers? i'm using the GT40p's now and the plugs clear fine? but there on a 302 also? peace


john

 

[Foxfan88]

the GT40Ps would be better but IMO i would get a nice set of aftermarket heads, those iron heads will be restrictive on a 351, and you wont be able to extract all the possible HP from the engine.

a 351 can make alot of power N/A but you need a nice set of heads and a good cam and intake to match.

 

[squeak93]

why would i have to modifiy the headers? i'm using the GT40p's now and the plugs clear fine? but there on a 302 also? peace


john

You have to buy swap headers to put a 351 in or use ur existing 302 headers and have ur midpipe swap. It can be done I am sure but not going to be a direct swap for the gt40p heads. U will also have to drill them out to accept larger head bolts if thats not already been stated in this thread (to lazy to go back and re read).

 

[SMOKEDYA]

You have to buy swap headers to put a 351 in or use ur existing 302 headers and have ur midpipe swap. It can be done I am sure but not going to be a direct swap for the gt40p heads. U will also have to drill them out to accept larger head bolts if thats not already been stated in this thread (to lazy to go back and re read).

knew about the head bolts i'll be putting the ARP head studs on order along with the balancer and flywheel soon.


enyawix use the GT40P if you spark plugs will clear the headers.


why would this be? peace


john

 

[85_SS_302_Coupe]

Considering the Lightning 351W came with GT40 heads, and the GT40P heads are generally considered to be superior to the non-P heads, the answer would logically be that the Ps would be your best bet.

Porting changes everything regardless of which heads you choose.

 

[lang williams]

what is the 351 head number...i read some where that the D08 or something like that is the only 351 head worth messing with. I got the gtp's an they sound strong but I haven't run it yet.

 

[65FBE2]

C9 or D0 are the only 351w heads that have 58 or 60cc chambers. anything else will drop your compression to smog levels

 

[85_SS_302_Coupe]

what is the 351 head number...i read some where that the D08 or something like that is the only 351 head worth messing with. I got the gtp's an they sound strong but I haven't run it yet.

Mine are C90E.

 

[Stopsign32v]

Neither if you wanna make decent power. But if you have to use one set then I'd go with the P's.

 

[SMOKEDYA]

well guy's i'm out here in ohio so some time this week i'm headed to jegs to look at the AFR 185's i'm getting here soon! I hope? i'm thinking of selling my H/C/I and buying the AFR185's. Whats a far price? gt40p's ported polished cobra intake (factory) off 93 cobra ported polished 1.6 cobra rockers trick flow push rods and not sure of the cam but it's loppy and is a crane. peace




john