vvelez5

Alright im still a newbie to all this and i want to get some aftermarket heads on my 5.0. I like the gt-40 heads but i see that there are different types and im wondering what do the CCs mean. dont i just bolt it on to the block? and what else would i need to have these things working? thanks for your help

Hung Like a Stang

Hmm, the actual head question is very vague.

But, the "CC" is the combustin chamber volume in cubic centimeters. the higher the number, the lower compression, and vise versa. (this is w/ your standard piston, a dished pistion will lower compression, an dome pistion will up the compression)

If you're staying naturally aspirated, you can run a higher compression (lower numerical valued "CC" head) and get a little more power if tuned right. If you want boost, get a low cr number.

Theres a lot to look into with new heads. Intake runner volume for instance, too big, and you'll bog hard on the low end. The combustion chamber volume previously discussed, Possible push rod length issues. You might want to run head studs and get a good head gasket. If you're looking into gt40P heads, you'll need a different set of headers and spark plugs.

There's a lot of info if you use the search function.

mjr46

depends on what gt-40 heads are to looking at?? cast iron gt-40's??....gt-40p's??? or aluminum head gt-40's??

vvelez5

i was doing much more research on the subject i was amazed to see the clock say 4am and i was still online learning about this thing but its very interesting and I'm going towards the side of the gt40p and obviously get the right headers to match those frpp made specifically for the gt40p now im just wondering if i buy the gt40p from this website would i still have to port them? (feels like a stupid question) but i hear porting out used gt40p heads can run pretty pricey

drhoward

porting any set of heads can be expensive


You don't need to port then, alot of guys do just to get more hp out of them

my77stang

check out these right here, probably the best bang for the buck GT40P's around...

http://www.tristatecylinderhead.com/...products_id=40



by the time you buy a used pair, pay for a valve job, new bigger valves, stiffer springs, and the extra machine work they will charge to open the heads up for the bigger valves you cant really beat this price.

*edit* i just emailed them to ask what kind of hardware they are using. if they tell me the valves are some chinese crap i would look elsewhere, or try to buy these just as bare machined castings maybe?

hillbilly pony

I would personally recomend just buying a matched kit like Holley or Edelbrock the comes with heads intake and cam push rods etc. this is more expensive BUT it will take all of the guess work out of your set up. After you put on something like that and enjoy the differences you FEEL. then you will gain a more clear understanding of how the "numbers game" involved with building a custom set up effects performance. Just compare whatstock feels like with the new feel after in kit. Youcancompare the statistics with the seat of your pants and it will begin to make more sence.

vvelez5

thanks for all your info the ones from tristatecylinderhead.com were the ones i was looking at because of the price for the pair. Oh and another question can i still use my stock cam for the GT40p's? and later on upgrade? I would love to get a kit from holley or edelbrock but like you said they are expensive maybe later on i would be able to get a kit if it would be less costly later on. i appreciate everyones feedback and 77stang i would appreciate it if you ever get a response from tristatecylinderhead.com about the valves thanks again

1991LX5.0

you can upgrade later but i would save a little extra and do the cam now. A cam is only $200 and if you do it later your going to have to spend $80 on a new gaket kit plus spendhours tearing it back down and putting the cam in. Id wait a few weeks and do it right the first time so your not kicking yourself in the *** later

w8less

or just run the stock cam and add 1.7's like in a cobra set up