F7TE GT 40 P heads EASY SWAP?

[stinkydogfilms]

Hi, Got a chance to get a pair of F7TE Bronco Explorer heads. Would they be an esy swap on a 91 302 EFI lo po in a 91 GM?

All of the head parts are there. Seller suggested a valve job and said that a GM exhaust would not fit up.
How much for a basic head job and how much should I pay to have them installed?

What should I do more than basic to the heads? Swapping heads seem like a big job to me, but so does changing a cam. Carbuerator or distributor no problem. I even swapped a couple of motors and trans in the day and both cars ran and drove. LOL
I believe the head swap, maybe headers and a 3.55 gear would make a big difference. Then comes the wide ratio gear swap in the good ol AOD.
Which shift kit and speed stall for the above combo?

14 inch tires or 15 inch for more low end?

I currently have a single exhaust system dumping into one cherry bomb glass pack under the rear axle turned down at the end to keep the heat from the gas tank.
I think it sound awesome and have been told a few times it doe sound good.
I don't know if I want to go to dual exhaust as I don't want to lose any torque.

Thoughts please.

[pantera77]

I'd start with this thread.

http://www.grandmarq.net/vb/showthread.php?t=3147&highlight=HO+Conversion+FAQ

[1987cp]

Torque when going away from a 2" single exhaust on a five liter engine? Yep, lots of people like to perpetuate that general type of myth. So far as I can tell, it stems primarily from people who made just one change that was inappropriate to the overall combination, lost torque on the butt-dyno because they didn't even bother to do any tuning afterward or else key components simply weren't playing nicely, and then declared that change to have been a Very Bad Idea in the first place. FWIW, there are guys on another site putting out stupid low-end torque using as much as 4" dual exhaust in some cases! Go join there and read their myths section if you want more info than someone like me can process, otherwise focus on our HO-swap tech and call it good.

I've gotten valve jobs for $200, but $300 and up seems to be more typical from what folks say. Definitely add the cost of valve jobs into the cost of the head swap - if you get into a set of factory heads that need a lot of work, it's said to quickly get to the point where it's more cost-effective to purchase a superior aftermarket head in the first place.

Installing heads is very easy, a very reasonable DIY job, so figure on $0 labor for install if you have the time. In-car cam changes are more of a pain (IMO) since the radiator and timing cover need to come out (IIRC), but if your plan is basically along the lines of the standard HO swap, you'll likely be wanting a secondhand HO or Explorer cam to go with it. There are numerous aftermarket options, including custom grinds, but these particular factory cams are cheap to obtain, high-quality, and (in my limited experience) pretty forgiving of having idiots wielding the timing light and the carb tuning kit.

I'd be surprised if lowpo exhaust logs didn't clear the spark plugs on "P" heads, and there are worse options than running a stock 2" dual exhaust, but the usual option for "P" heads around here seems to be the FRPP "P-specific" shorty tubular manifolds, in conjunction with an aftermarket Mustang crossover pipe. Typical arrangements include 2.25" H pipe to 2.25" midpipes (from an S-10) to 2" stock Vic tailpipes (stock Caprice mufflers are 2.25" in and 2" out), and the theoretically superior and ever-popular (but fairly loud IMO) 2.5" all the way back using aftermarket tailpipes for a '95 Impala SS. One doesn't usually hear of people running 3" or larger exhaust on Panthers to my knowledge, but that could obviously be worth considering, depending on your goals. And of course, one shouldn't overlook the possibility of modifying real headers to fit.


I don't understand the question about wheel diameter ... stock tire height is 27" overall, which works fine for most people, and whether you use a 205/75/15 or 235/60/16 or 255/50/17 to accomplish that is up to you.

[mcninetyone]

When I put an Explorer 5.0 in my 91CV, I had the choice of either
GT40 or GT40P heads. Naturally I wanted to use the 'P's", and tried several exhaust manifolds to see which one would clear the plugs. Not a one of them cleared the plugs without at least some modification, and still it was a tight fit.

I tried:
stock cast iron manifolds
TC tubular exhaust manifolds
Mustang stock headers
early model small block ford manifiolds, which seemed to be the best!!!

But not a single one was without issues.

Finally to avoid the problems and not wishing to spend hundreds on headers
and redoing the 'H' pipe. I went ahead and used the GT40 heads with the TC
tubulars. They work just fine, the car runs great and my plugs are right there
where I can get to them. The extra cost and problems using the GT40P's just
wasn't worth it to me.

[1987cp]

True there about the FRPP manifolds seeming pricy when you're trying to do it on zero budget (as I usually am), though I don't recall them being much if at all pricier than quite a few popular aftermarket manifolds.