Official GT40P headed 300rwhp thread!!!

I have a 1999 Mountaineer GT40-P engine with about 16,xxx miles on it and the following...

-'96 Explorer intake
-65mm throttle body
-BBK unequal length shorty headers....2 1/2 inch off road X-Pipe,40 series Flowmasters,and Mustang 2 1/2 inch mandrel bent tails.
-Trick Flow Stage 1 cam
-Ported "P" heads with Trick Flow springs
-1.6 SVO roller rockers going on as soon as I get the time

Timing is set to 14 degrees as of now and seems to be working well at that.The car is equipped with the T-5 and King Cobra clutch.

I have no idea what the horsepower is right now.The engine feels strong,and runs flawlessly.I'm planning on upgrading to 24# injectors eventually,but I have a/c and a couple of other things at the top of the list. Any idea of the power this combo may have?
 
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I'm in the middle of a 4 to 8 swap and just getting my motor together. I got a deal on some gt40p bare heads and some good spring and s.s. valves. Got a explorer intake and ford racing headers from Stangnet members. Running e303 cam with 3.27 gears. I'm dying to see how this combo works. Great thread!!!
 
You are correct sir!

Seriously though, Tom you know what I am referring to. No need to make smart comments that will only confuse those who dont know any better.

Venom351R has AFR 185s, a custom cam, and a TFS R intake....and doesnt have over 350rwhp on his 351.

I'm making a point - and I know of some AFR 185 head 351 engines that make more poer than that. I know of a 195cc 363 making 450 to the tires.

My point - It's not good to generalize.
 
I'm making a point - and I know of some AFR 185 head 351 engines that make more poer than that. I know of a 195cc 363 making 450 to the tires.

My point - It's not good to generalize.

Obviously his combo isnt the end all be all for 351 combinations. And a average "joe" is not going to put together an extremely powerful "pro stock" like combo. On these forums its not common to see a 363 making 450rwhp. Perhaps guys on hardcore50 pull those numbers since they are much more experienced. Stopsign32v (sp) proved a point a while back on the size of parts that you choose to put on a motor....although his combo was too radical for his wants to drive it all the time....it put out power that most wouldnt have guessed.


You are right, most generalizations arent appropriate and can be proven wrong....and I could be wrong when I make this guess....but a "ported" gt40 head on a 351 is not going to outpower a AFR185 or similar type of head.




But hey, what do i know. Throw ported gt40p's on a 351 and go take out some LS1s :rlaugh:
 
Show me a dyno test that says GT40s on a 351 won't make more power then the exact same head on a 302. You have more displacement and when the piston goes down it MUST draw in more air, it's physics at work here, I didn't make those laws. If there's a bigger cylinder pulling in more air, when it compresses the mixture there is going to be MORE OF IT, regardless of anything else. So it will make more power period. Might only be 1 extra HP, but it must make more power, it has no choice.

Now, will the car be any faster? Maybe not because of the extra weight of the windsor block under the hood, but I guarantee it will feel quicker off the line because it will make a noticeable amount of extra torque.

And if someone can pull 300 rwhp out of a GT40 headed 302 then 350 from a windsor shouldn't be difficult either. And stop quoting what people are making with 351's with AFR 185s, because out of your own mouth, "351's with 302 parts make 302 power" and last I checked the 185cc AFR IS a 302 head.

And no offense to Venom, but 350 RWHP is kinda weak for that combo.
 
Show me a dyno test that says GT40s on a 351 won't make more power then the exact same head on a 302. You have more displacement and when the piston goes down it MUST draw in more air, it's physics at work here, I didn't make those laws. If there's a bigger cylinder pulling in more air, when it compresses the mixture there is going to be MORE OF IT, regardless of anything else. So it will make more power period. Might only be 1 extra HP, but it must make more power, it has no choice.

Now, will the car be any faster? Maybe not because of the extra weight of the windsor block under the hood, but I guarantee it will feel quicker off the line because it will make a noticeable amount of extra torque.

And if someone can pull 300 rwhp out of a GT40 headed 302 then 350 from a windsor shouldn't be difficult either. And stop quoting what people are making with 351's with AFR 185s, because out of your own mouth, "351's with 302 parts make 302 power" and last I checked the 185cc AFR IS a 302 head.

And no offense to Venom, but 350 RWHP is kinda weak for that combo.



LOL

The entire point of the saying is dont expect to make true 351w power with 302 parts. Dont use small parts on a motor that wants bigger parts!!!! I truly thought this wouldnt need to be said because even if u take 2 302s, give them the same head, intake, cam....they wont dyno at the same exact number. Come on man... Stop taking it so literal. Its obvious it will make more power than a 302 and not the exact same number. Its also obvious it will make better torque at a lower rpm. But again, stop taking it so literally.



Since you want dyno numbers, where is a 351w combo with gt40s that has cracked 350rwhp :shrug:


I must have missed where i said an AFR185 head is the IDEAL head for a 351. Im simply saying that a AFR185 head is many times better than a gt40 head. Thus, i would be very impressed if u can beat Venom's combo (afr185/FTI cam/tfs r intake) with a gt40 head. Again...im kinda disappointed that this actually has to be spelled out tho. :( (just bustin your balls mark :D )



You're a funny man :lol:
 
Either you mean something or you don't.. there's no dodging the facts. Everyone knows that your "high" expectations on your windsor build will fall flat if you go with smaller 302ish parts. But putting those parts on these motors does have a purpose. Not all of us are made out of money, so we have to cut corners to see our projects come to life. Anything AFR makes is outta my budget, they've gotten so damn full of themselves that you have to be rich to afford their stuff!! Looks like GT40s for me! lol
 
Hey Tom, what's the details of that 363 you're referring to? Is it a high rev motor? Big cam?What kind of intake? Is it a street car? A/c? Power steering?

AC Cobra clone (Excaliber), Dart block, Dart 195 CNC heads, ported Vic Jr, 850 Willeys Holley, solid roller cam that revs to high 7,000 rpm band, 1 3/4" Jet-Hot coated headers into 3" side pipes, T56 into a Ford 9" with 4:10s or 4:30s depending on tires and track. Runs 10.50s on the motor, 9.70s @ 139 mph on a 150 shot with a 1.36 60'.
 
I have a 88 Lx stock bottom end.. Gt40p heads all cleaned up, new stainless valves, new stock springs, the exhaust valves are 1.54 instead of 1.46, no port work on heads. Explorer intake, gasket matched lower. 1:7 roller rockers, 65 mm tb, 70mm mass air, stock box with k&n, g force t-5,ram clutch, aluminum driveshaft, electric fan, ucas,lca's frame connectors, hurst shifter, 3:55 gears, 245 50 16 nitto drag radials, pulleys, no smog pump, mass air conversion..dynoed before heads and intake 263hp, 315tq... And 13.6 @ 100mph with 1.9 60ft.. Going to the track next weekend... Hoping to be in the 12's or damn close.. Anyone think this is a possibility?
 
Yeah I thought they seemed high.. But we did 3 pulls and they were all about the same.. The lower intake was ported..I don't know if that makes much of a difference.. The bottom end I was told when I bought it is a 93 cobra crate shortblock.. But I don't know if they were any different than a stock 88 bottom end..
 
What cam are you running? Nonetheless, good numbers. As far as your previous question, 12's are definitely a possibility. A good 60' time will get you close and the heads and intake should be good for a few tenths. Keep us posted.
 
I kept the stock cam cause I am going to build a twin turbo setup with the turbo coupe turbos..I will post track numbers after this weekend.. I need to get it dynoed again too..getting a tune would be a waste of money at this point in time right?
 
Ok.... I am disappointed...no gain anywhere at the track... Just makes me wonder if I did somthing wrong when I put the heads on.. I even put a fiberglass hood on, and took the a/c stuff out..if my mass air meter is calibrated for 24's and I have 19lb injectors would the car still run? I took the mass air meter off and it has a 24 written in marker on it..which makes me wonder if it is the right one..it is supposed to be from a 94-95 gt..