Heads have different size exhaust valves. Different plug angle( for the P's) and supposedly the casting of the P's are slightly better. IIRC the combustion chamber CC is different also. I could be wrong though
right on
earlier intakes have the EGR hole and a spot on the #5 runner with a little extra "meat" for drillign/tapping the act sensor,thats the only difference there
everything you said about the heads rings true to me..
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92 lx 5.0 vert-,stock plastic airbox,stock T-5,shifter & clutch,stock 19lb injectors and fuel pump,no radio,speakers or cruise control..antenna delete(for less wind resistance)
(new)best so far 12.712 @ 105.99mph 1.752 60ft
the p heads actually flow a little better,but everyone is scared of them cuz they have to buy new headers,or so they think..the most popular of all headers,BBK shorties are known to fit with 90* boots..they're like $150 or so brand new
people end up paying 2x as much for a set of used standard style GT40 heads compared to the GT40P heads,when they could score the P heads AND a new set of headers for the same price as the standard GT40's..i just sold a set of standard explorer GT40's on ebay last nite..they went for an unbelieveable $415 + shipping (i still dont believe it myself lol)
P heads go for around $200+ shipping for the most part..you tell me which makes more sense lol
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92 lx 5.0 vert-,stock plastic airbox,stock T-5,shifter & clutch,stock 19lb injectors and fuel pump,no radio,speakers or cruise control..antenna delete(for less wind resistance)
(new)best so far 12.712 @ 105.99mph 1.752 60ft
an important point about the heads is that the GT-40 comes with a larger combustion chamber than the ET7E so to keep the same compression ratio you need to milled, in the other hand if you install a set of GT-40p heads in a stock 5.0 you will raise the compression ratio from 9:1 to 9.5:1 because of the smallest chambers and if you cu it or milled to 30 mm you will get a closest 10:1 compression ratio.
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GT 1991 convertible,GT40p heads, explorer intake, 65 mm TB, 70 mm Maf, MSD 6A, K&N filter, FlowMaster 40 Series Delta flow, 130 amp 3G alt., taurus electrical fan with derale fan controller, MSD wires, 3.73 rear end, mega bite jr. lower control arms, R-17, AOD with 4R70W internals and a B&M shift kit
what i see, is that the explorer cobra or GT-40 intake have an a range between the 1500 to 5500, and i think the range of work in the edelbrock is 2500 to 6500, if you have an a stok engine or little modify, then the edelbrock it seems to be a litle to much for the aplication, besides, the ford intakes is a cheap and good option to get more horsepower
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GT 1991 convertible,GT40p heads, explorer intake, 65 mm TB, 70 mm Maf, MSD 6A, K&N filter, FlowMaster 40 Series Delta flow, 130 amp 3G alt., taurus electrical fan with derale fan controller, MSD wires, 3.73 rear end, mega bite jr. lower control arms, R-17, AOD with 4R70W internals and a B&M shift kit
Last edited by gerzen; 08-25-2009 at 11:39 AM.
Reason: spelling
Wow, I have a 66 convertible that I am going to be a 5.0L in with a t-5. I got a 1991 225HP HO engine. I was thinking about going with the Cobra (GT40) intake and the GT40 heads. I had noticed that the Non p heads were move expensive and heard about the plug angle. I like the idea of miling the cylinder to get 10.1 compression. So I have two questions maybe someone can answer for me.
1. Will the BBK shorties work in a 66? Clear the stearing, etc.
2. I am considering a rebuild that will allow the car to run on E85 if desired. The 10.1 compression will help. Not to mention the bigger injectors and heads. I have to run stainless steel fuel lines, and probably will need a different pump. Does anyone know if the HO computer will adjust and advance the timing and fuel spray? If not, can I use a programable computer to make it work and toggle back and forth to regular gas?
I love the site!
Here are pics of my project and engine. Engine, 2 ton hoist, and stand were a craigslist find for $300
just a guess on the computer stuff,but check into something like the twEEcer r/t or anderson ford PMS..they dont make any handhelds for the EEC IV as far as i know(PMS is close,kinda),but those 2 i mentioned are TOTALLY adjustable
