GT-40 Head users come on in...

[fastimes69]

I recently got some cast iron GT40's off a 94 Cobra with 31,000 original miles.I will be putting these on a rebuilt block with bolt ons.GT40 intake,E-cam,pullies, exhaust,65mm TB,etc,etc.My question is it possible to run 12's with these heads unported and with bolt ons.This set up is going in a stripped 89 LX hatch,5 speed that will be used for racing only with a dual stage NX N2O.I know there are several guy's out there with P heads but my question is for the regular GT40 head users.What set up do you guys run and what are your times?

 

[90]

i have the original iron gt40's but i havent taken it to the TRACK yet!

 

[MAC'n89Blckstng]

I have the EXACT same setup, I went 13.8 so far with a little boggy launch, I think its goof for a 13.6-13.7

 

[carbed87]

yeah, i had similar mods and couldn't break a 14.7 at 5280ft... so maybe with more mods, but i dunno

 

[oldschool88vert]

how much is the car lightened? that can make a big difference too. and how big a shot.

 

[25thmustang]

That combo should be good for 240-250 rwhp, and deep 13s if not 12s on a tire. Cars rarely run the best pass on the first or second outing, so take that into consideration!

 

[MAC'n89Blckstng]

I cant shift fast either b/c Im affraid Im going to grenade another T-5

 

[mob]

stock intake? If you get a cobra or explorer intake, slicks and powershfting you should hit 12's, with the nitrous deep 12;s

Just saw you had the gt40 intake

 

[rd]

My 82 runs 12.90 or so on motor with a set of these raggedy old iron heads off a 94 Lightning truck. I have a 1986 cam and not a lot of compression. I did mill them 25 thousanths. Has run 7.80's in the eighth on spray.

I think these are some of the best iron 5.0 heads out there. They bolt on easily, are a definite upgrade, and seem to be durable.

 

[25thmustang]

Great heads for a street set up!

 

[fastimes69]

The LX my cousin and I are building has been gutted.No carpet,door panels,back seat,all A/C stuff under the dash has been removed,front and rear bumper supports,sway bar removed,and still trying to remove other stuff but we're out of ideas.It will have a cowl hood and looking into getting a fiberglass hatch.It is very light as it is already.The NX dual stage kit we have is adjustable if I remember correctly from 100-300 shot !We plan on going with a 300 shot once it is running.We hope it will run low 11's to high 10's once we get it running.It will be a track only car.

 

[fastimes69]

Oh and this same car ran 11.70's with a different set up before.It was a stock engine,stock heads,stock cam,rockers,throttle body,air meter,FPR,everything on the engine was factory stock with 5 speed.The mods were 1 5/8 shorties ,h-pipe,4.10's,9 in K&N conical filter,short belt with a 3in race crank pulley,electric fan,and a 150 shot of N2O.On motor it went 13.10's at 103mph.It could have gone quicker with some tuning.So we should run quicker with our new planned set up..

 

[5ive.oh]

I have ported GTP's and am able to beat my friends 06 GT with 4.10's, a CAI, diablo tune and flowmaster exhaust. I do it on 205 street tire too.