GT40 cast iron heads.......

Vinnietbird · **GT40 cast iron heads.......**

Will the GT40 cast iron heads work on an '86 H.O. 5.0 with flat top pistons?I don't want to swap pistons right now.Thanks.

THUNDERJET T/C · **Re: GT40 cast iron heads.......**

they should be fine if you keep a stock camshaft such as the h.o cam

Vinnietbird · **Re: GT40 cast iron heads.......**

Thanks,no matter where I check,i get differing opinions.I'm not swapping the cam or the pistons.All I want to do is swap the heads.I'm going to go ahead and grab the lifters and pushrods from the Explorer engine ( I don't need them,but they're free,so,what the heck).I'd like to have the whole long block,but he has plans for the block itself.I can't beat $100.00 for the heads.I was told they should add about 35 to 40 horsepower over the E6 heads I have now (yes,I know the E6's suck).Any ideas on the power difference?

THUNDERJET T/C · **Re: GT40 cast iron heads.......**


Quote: Originally Posted by Vinnietbird Thanks,no matter where I check,i get differing opinions.I'm not swapping the cam or the pistons.All I want to do is swap the heads.I'm going to go ahead and grab the lifters and pushrods from the Explorer engine ( I don't need them,but they're free,so,what the heck).I'd like to have the whole long block,but he has plans for the block itself.I can't beat $100.00 for the heads.I was told they should add about 35 to 40 horsepower over the E6 heads I have now (yes,I know the E6's suck).Any ideas on the power difference?

you should see about 30 h/p from the heads. if you use the intake and throttle body id say another 15-20 h/p.

i would look into maybe a b303 or e303 motorsports cam there would be another 30 or so h/p and make a nice combanation with a broad torque and power range

Vinnietbird · **Re: GT40 cast iron heads.......**

I'm using the Explorer intake now.I need a 60mm throttlebody.I'm looking for one from an Explorer for cheap.I'll modify it to work on my 'Bird.If I go to one of the cams you mention,would that be too much for my Speed Density car to handle......until Mass Air next year?I'm also looking for a cheap used set of better than factory headers (like I'm using now).Budget is TIGHT.One step at a time,I guess.

THUNDERJET T/C · **Re: GT40 cast iron heads.......**


Quote: Originally Posted by Vinnietbird I'm using the Explorer intake now.I need a 60mm throttlebody.I'm looking for one from an Explorer for cheap.I'll modify it to work on my 'Bird.If I go to one of the cams you mention,would that be too much for my Speed Density car to handle......until Mass Air next year?I'm also looking for a cheap used set of better than factory headers (like I'm using now).Budget is TIGHT.One step at a time,I guess.

we have ran a few speed density cars on the b and e 303 but thats as large as you can go without having idle problems

theres some sets of 99.00 1-5/8 shorties all over e-bay they will work fine.

a stock 60mm mustang 5.0 throttle body will also work with the stock linkage

Vinnietbird · **Re: GT40 cast iron heads.......**

Yea,I've got a 60mm (I meant a 65mm,my mistake),but the Explorer 65 T-Body requires a new throttleshaft arm.Only takes about 15 minutes to swap out.Plus,an Explorer 65mm unit is pretty cheap.After the heads,I'm going to get an adjustable fuel pressure regulator and fuel pressure gauge,gaskets (of course),and headers.One piece at a time....heads first,then the collection will grow until I have all the bits and pieces for assembly.Thanks.

Zim · **Re: GT40 cast iron heads.......**


Quote: Originally Posted by THUNDERJET T/C you should see about 30 h/p from the heads. if you use the intake and throttle body id say another 15-20 h/p. i would look into maybe a b303 or e303 motorsports cam there would be another 30 or so h/p and make a nice combanation with a broad torque and power range

Just for a power reference, I put down 277rwhp and 308 tq with the e303 and ported GT40s in my cobra

Vinnietbird · **Re: GT40 cast iron heads.......**

How good is the cam with flat top pistons?Will it cause an irratic idle?Thanks a lot.With me having Speed Density,the thought of a cam change is a bit scary.