HELP WITH HEADS

[tonys88lx]

got a couple questions on heads, i have a lead on some gt 40s for a good price im waiting to find out if they are Ps or regular i should know tomorow. 3 bars are regular and 4 bars are Ps correct? now im running 1.7 rr with a b cam. i heard that the p heads have a smaller cc but also have a smaller exhaust valve. so wouldnt it make sense to get the regular gt heads since they have a larger exhaust valve but they have a larger cc, im thinking if i just milled the heads i would attaing the smaller cc and have a larger exhaust valve, im not positive on all this so help me out, also i have longtubes and they are the slip tube type im not sure what brand they are cuz they have no markings but will they work with the p heads:SNSign:

GT40 Heads
3 bars
1.84" Intake/1.54" Exhaust
Cast Iron
65.5cc combustion chambers

GT40P Heads
4 bars
1.84" Intake/1.46" Exhaust
Cast Iron
59cc combustion chambers

 

[tonys88lx]

ttt comon guys u gotta have something to say

 

[BlownFiveLiter]

Due to the revised combustion chamber design of the GT40P heads which located the spark plug in the center of the combustion chamber, they were able to increase exhaust flow over the GT40, while using a smaller valve. Check out this site for just about everything you'd ever want to know about the GT40P heads. And welcome to :SNSign:

 

[natestang5.0]

i just installed a set of gt40ps on my 89 5.0 and the compression is so much higher my stock mustang battery sometimes will not turn it over. They are a good head swap for the price. Hope you have a whole weekend to do the swap.

 

[Tonys96Cobra]

Due to the revised combustion chamber design of the GT40P heads which located the spark plug in the center of the combustion chamber, they were able to increase exhaust flow over the GT40, while using a smaller valve. Check out this site for just about everything you'd ever want to know about the GT40P heads. And welcome to :SNSign:

Most LT headers will fit with the p's, you will need to run 90 degree plug boots at the worst. I think the Flowtechs you have to hammer the #4 pretty good.

 

[tonys88lx]

awesome

well thanks for all the replies so far keep em coming. Now i already emailed thumper as of last nite about porting and valve springs, but what do u guys think i should do to the heads machine shop wise? this is a street car that will see the track but its important to me to have low end power because it is a street car and its an automatic.And besides i have nitrous for top end powa. But what are some important things that i should definately have done to the heads. I dont have much money but i dont want to cut corners so nothing crazy. thanks

 

[2000xp8]

Buying a Gt40 iron head, p or not, then paying to have the valves changed and then the heads ported is a waste of money.

You are saying a "good deal" How much?

Say for example $250 for the heads, that's what i would consider a good deal, then $500+ in headwork.
Here in NJ, for a valve job with NO parts, you are at $250 alone. $100 for milling, then you need $100 springs, and you really haven't done much.

You are almost at what you can buy used heads that will make twice the power. Gt40x aluminums, twisted wedges, edelbrock rpms. I've even seen the x's for $850 NIB.

If you want to buy gt40 irons and just drop them on, because you are on a budget, that's cool, just don't drop any extra money on them.
If you need more power, save up and buy something better.

 

[tonys88lx]

heres the deal

im getting the gt40s for 175, thats a pretty good deal if u ask me. Now since im running a b cam with 1.7rr there will b float issues so i figured if i was installing new springs maybe i could get a basic port job. I have no clue on prices since i have not gotten that far yet. thanks

 

[2002BLGT]

im getting the gt40s for 175, thats a pretty good deal if u ask me. Now since im running a b cam with 1.7rr there will b float issues so i figured if i was installing new springs maybe i could get a basic port job. I have no clue on prices since i have not gotten that far yet. thanks

get them , and order the trickflow OEM upgrade spring kit I think its like $130 bucks , valve stem seals will run about 30 bucks and you can lap the valves yourself if you have time and patience doing it , its not rocket science to getting a good seat on them .......if you have the extra time get a good die grinder and gasket match the ports yourself ....shops around here will mill the heads for 25 bucks a head but don't go more than .020 on them ......you will have some time in them if you spend the time to port them , but I would be with all the above done a minimum of 35-40 horse power or more at the crank over the stock E7s, oh and trade your 1.7s for some 1.6s you might have clearance problems with a B cam and 1.7s with stock pistons

 

[tonys88lx]

roller rockers

I really dont want to trade my roller rockers for 1.6s, the motor i built my buddy we used a e303 cam with 1.7rr and gt40s with no problem. so i think i should b fine. i really want the extra lift out it.Its not much but it will make a differenc.:SNSign: