iron head choices

dresmnkaos

New Member
Jan 28, 2004
100
0
0
looking to throw on some iron heads til next year when the boosted stroker gets built. then ill be looking into some AFR's.

ive heard of ppl putting 289, 351, GT40 heads, etc. on 5.0's. which set of heads would be the best to monkey with and slap on my motor. keep in mind id be willing to port/polish these heads to livin em up.
 
i can pick up a set of gt40's for 80 bux any day of the year. throw int another 300 or so and have some nice iron heads. what about 351 heads? do they have more potential than the gt40's?
 
What cam are you guys using when bolting on GT40P heads? What headers are you using? What rockers are you using?

Reason I ask, is I just sold a 98 Explorer 5.0L yesterday that had the four lines in the heads..P's right? I should have charged him a core to get his motor back. I could have clean those old heads up and installed them on my black notch.
 
p specific headers or I have heard that the 351 swap headers work too.
I have a set of FRPP 1.6rr's that I am going to be using on my gt40's
 
That is what I would want to do. Stock bottom end, new timing chain, stock cam, GT40P heads, Explorer upper and lower intake, stock dizzy, stock T-body and EGR spacer.

Oh...what size injectors with my list of parts.
 
In my experience, standard Windsor 351 heads DO NOT have more "potential" than gt40p heads.


"Out of the box", no, but when you consider what can be done with porting, then that changes everything. Of course, you could also port the P's so it really just depends on where you start. I scored some '69 Mach 1 351W heads that were already professionally ported and polished and already had 1.94/1.60 valves in them for $260. I ended up having to put another $450 into new stainless valves, but the port work on these heads is good enough to justify it...they'll run right along with any of your entry level aftermarket aluminum heads. Of course deals like that don't come along too often so i would opt for some standard P heads over anything else, unless you wanna get Thumpers or look for a set of used aluminums. I almost got a set of Dart Windsor Sr.'s for $700 that were ported and flow bench certified to flow 310cfm, but they got bought out from under me.
 
the new 5.0 magazine that came out did a HCI consisting of BBK intake manifold, Dart iron eagle heads, and anderson n-41 cam...and some little stuff like throttlebody, injectors..etc.
They gained 164whp, and 130wtq, but lost a avg of 8whp and15wtq between 2500-3300rpms. I think the losses were due to the bbk manifold. The heads flowed 159cfm at .500lift on the exhaust but I don't know what on the intake.
Baseline power was 181whp @4100rpms, and 248wtq @3200rpms
HCI power was 284whp @5100rpms, and 293wtq @4500rpms
 
Yeah, I saw that gain in the new mag. That makes me want to throw those on my black notch, but I just can't see spending 3K on my car that already runs perfect...even though it's stock and kinda slow.
 
They gained 164whp, and 130wtq, but lost a avg of 8whp and15wtq between 2500-3300rpms. I think the losses were due to the bbk manifold. The heads flowed 159cfm at .500lift on the exhaust but I don't know what on the intake.
Baseline power was 181whp @4100rpms, and 248wtq @3200rpms
HCI power was 284whp @5100rpms, and 293wtq @4500rpms

That's an incredible gain with just a HCI project.... 164 horsepower? You might want to recheck those numbers. 159 CFM on the exhaust ain't even great. A crappy port job would probably get that out of GT-40P heads.

Gettin' back on topic...

The GT-40P heads are readily available and as such are the logical choice.
 
That's an incredible gain with just a HCI project.... 164 horsepower? You might want to recheck those numbers. 159 CFM on the exhaust ain't even great. A crappy port job would probably get that out of GT-40P heads.

Gettin' back on topic...

The GT-40P heads are readily available and as such are the logical choice.

Your right the magazine said at 5317rpms baseline it had 142whp but then at 5374rpms it had 118whp.....so peak gain was actually at 5317rpms it went from 142whp(baseline) to 283whp(HCI).
 
Your right the magazine said at 5317rpms baseline it had 142whp but then at 5374rpms it had 118whp.....so peak gain was actually at 5317rpms it went from 142whp(baseline) to 283whp(HCI).

The next time they run the dyno they need to make sure that they put the other 4 spark plug wires back on the baseline before they dyno it. The 283 hp isn't the number I question, it's the 142 hp that is way off. The lamest numbers I've ever read about on a 5.0 was in the 180 to 190 hp range. :shrug:
 
the only bad thing about the "P" heads is the requirement for special "P" headers. i have some bbk and mac unequal shorties. will either of these two work on "P" heads? from what ive read no, but maybe you guys know differently.
 
Iron heads... GT40's.. GT40P's, Ported E7s or ported GT40s.. they all will allow over 400 BHP and most HCI combos are pulling 150+ whp!! Get what you can.. then you can always upgrade with port work.. yes??

Just me..................................

Thumper
 
the only bad thing about the "P" heads is the requirement for special "P" headers. i have some bbk and mac unequal shorties. will either of these two work on "P" heads? from what ive read no, but maybe you guys know differently.


I am running BBK unequal's with my P heads, I only had to run a 90* sparkplug wire to #7 cylinder to make them work, all of the other plugs had room to spare.