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STOCKSPLASH
Mar 15 2007, 06:52pm
My brother built a good shortblock that I'm thinking of throwing in the truck this summer. 0.030 over, forged pistons, Lunati cam (about 210* w/ 0.500" and 0.510"). Nothing too special just stock shortblock with a cam.

Anyways, I've been looking at going with a pair of AFR 185's or something comparable. My brother think's I'd be happy with a set of GT40 heads. I told him I want to put down around 350-400hp to the wheels. And whats the diff. between the GT40P and GT40X heads?

But what kind of numbers are you guys putting down with GT40 heads?

Ranger50
Mar 15 2007, 07:32pm
Don't be hung up on RWHP numbers. To achieve 400rwhp, you will need nearly 500 flywheel hp. That is far from "livable" on the street for very long. Plus you will need a MUCH larger cam to even get close to 400rwhp in naturally aspirated form. It will be a turd to drive from the lack of torque, IMO.

Gt40x heads are aluminum versions of the GT40 head in essence. The GT40P's are an "updated" version of the GT40's which the performance advantage is debatable over the originals.

suruat98
Mar 15 2007, 07:40pm
The best way to achieve what you want is to add a Supercharger. That motor alone with just head will maybe push 300 hp.

freakinmacguyvr
Mar 15 2007, 11:28pm
I have a fairly stock short block, 9.5:1 forged pistons and trick flow track heat stage 1 cam, which is about the same specs as your Lunati. My gt-40 irons are fairly well ported, along with the gt-40 intake. I put 210 hp and 252 tq to the ground thru a 4r70w with stock explorer ecu. The dyno says it will run a 14.8 1/4. Have to wait to see that.... Oh, and the gt-40p heads are a pain to find headers that will clear the spark plugs.

STOCKSPLASH
Mar 16 2007, 02:16pm
Here is the deal. I've got an 86 longblock with an AOD that I planned on building to my liking this summer. My brother wants me to use his motor and some GT40 heads, which he thinks will be "enough" for me to be happy, lol.

My original plans:
-Ford Racing X-cam
-Aluminum AFR 185cc heads w/ 58cc chambers
-Good EFI setup (24 or 30# injectors), 75mm MAF and T-body
-Trickflow upper and lower intake
-1 5/8" headers and some Dynomax mufflers
-T5 with a good strong clutch
-4-link with some 275 or 295 ET streets out back

Now, I'd like to get it running this summer, so I might just start off with a 650 Demon through a Vic. Jr. intake for now and piece together the EFI setup later.

pinellas50
Mar 16 2007, 02:37pm
http://www.rangerpowersports.com/forum/showthread.php?t=187435

WhiteLX
Mar 28 2007, 08:13am
My Mustang made 281rwhp with my Crane 2031, ported GT40 iron heads, Performer intake, 65mm throttle body, and 1 5/8 shorty headers. Full details on the combo are on my website.

You 1986 shortblock will need new pistons or have the stock one flycut for valve clearance.

MichiganSpecial
Mar 28 2007, 07:55pm
The GT40P's are an "updated" version of the GT40's which the performance advantage is debatable over the originals.
Stock for stock, the P heads are better. Argue with me if you want... Although, for the pain-in-the-ass factor, stick with GT40 iron heads and don't waste your money on GT40 AL heads unless you get a GOOD deal. Even so, make sure you get the GT40X AL heads.


Oh, and the gt-40p heads are a pain to find headers that will clear the spark plugs.
Not so much to find headers to clear the plugs, but headers that will fit between a Ranger's frame. I can vouch for it. Are there any other Rangers with a 302/289 and GT40P heads???


My original plans:
-Ford Racing X-cam
-Aluminum AFR 185cc heads w/ 58cc chambers
-Good EFI setup (24 or 30# injectors), 75mm MAF and T-body
-Trickflow upper and lower intake
-1 5/8" headers and some Dynomax mufflers
-T5 with a good strong clutch
-4-link with some 275 or 295 ET streets out back

I just took a X303 cam out of my engine...

trailhead00
Mar 29 2007, 05:11am
I have an 2000 mountaineer 5.0 with the GT-40P heads With FMS Headers. Tourque Monster also makes headers for this application. I know the 98 up 4x4 or torsion bar suspension rangers do not have clearance problems with the steering box or frame, for reasons the explorer/mountaineer motors (302) were based into the torsion bar suspension. So if you have the pre 98 rangers most definetly you could have an issue with clearances. But I know from experience the "P" heads have no issues with 98+ torsion bar rangers.


Todd

2.3'dranger
Apr 04 2007, 10:41pm
Btw how good are the gt40 x heads.?i was looking into a set to lighten up the front end and gain some power also. in 5.0 mustang mag there is a setup that has an e cam, the gt40x heads, 1.7 rockers and cobra intake manifold for like 2100 i belive. is that a good price and an ok setup to use in a 99 mounty 5.0 motor. thanks

MichiganSpecial
Apr 05 2007, 12:49am
for two grand you can get better heads. AFR is where the wind blows now days. TFS Twisted Wedge are also great. Edels are always good. The GT40X AL heads aren't that great. I wouldn't buy them new, personally.

jaybo
May 01 2007, 10:48pm
I would not buy the x heads new. If they were used and (cheap) maybe. The afrs are the way to go. You can make 400hp with a big cam and afr heads but unless you have a 5 spd and gears it will be a dog off the line. You would probably be happy with some cheap ol gt40 P heads which out perform the gt 40s up untill about 5k rpm. torque is what gets you out the hole and makes for a better street truck. I have a 99 explorer 5.0 with the p heads, FRPP headers, and a crower 15511 cam and cobra 1.7 rr. 75 prom maf (about 300 flywheel hp) and it is a beast. I do wish for the afr heads though.

MichiganSpecial
May 02 2007, 06:30pm
Although I have P heads on my truck, I do not recommend them; you'd have to use tri-y headers and beat the #5 tube in or use Hedman 88400 shorties, which will eait fit or you'll have to do some minor beating to the #5 tube. If you want to use iron heads, eith get the GT40 cobra/ex heads or 351W C9/D0/D5 heads.

Chico
May 22 2007, 06:48am
P-heads can put down good numbers, but to be honest they are a bit behind now a days. I look at it like this you can still get a GT-40 intake from Ford for ~500.00 or so, but for 500.00 I rather buy a trick flow intake! I run GT-40P's on my Mustang with great results, 515 RWHP, but thats with a blower, and if I put on My AFR's I'm guessing I would pick up about 20-25 HP. The Headers are the real pain in the ass, I had to make a custom spark plug wrench to get my plugs out... if not you have to pull the headers free to change the plugs every time. Not worth it! They were great back in the day 1990's when they were one of the few options available, but now a days I would get a set of AFR's hands down. I own both, and would dump the P's if I could!

400sxman
May 22 2007, 07:34am
i have a 2000 explorer 302 with gt-40p heads, torque monster headers, and a mac intake that puts 235 down to the ground. from all the research i did (i want 400 rwhp too) your best bet for more power and the cheapest way as well is to get a kenne bell blowe ron there. all said and done, you should be able to do it for $2500 (look on ebay for deals) the best part is it will be very streetable. hope this helps.
~Nat