head swap

[legalize420]

i just picked up a set of used gt40's. i plan on doing some searching and reading up more on the swap within the next few days. couple of questions. what will i be able to reuse. should i invest in some rockers. the heads have a little over 100k on them. do the springs need to be changed. i will definetly be picking up the new bolts but should i get some new pushrods while im at it. thanks

 

[txstang84]

at a bare minimum, they should probably be inspected, so you can determine whether or not you will need to change any parts. with 100k miles on them, they should probably have a valve job and maybe change the springs if your planning on running a bigger than stock cam. any competent machine shop will be able to ck them out for serviceability, have them all cleaned up for you and they should ask you what cam you're planning to run (this will determine what type springs to run). and yes, IMO pushrods are a good investment just for good practice sake.

 

[legalize420]

at a bare minimum, they should probably be inspected, so you can determine whether or not you will need to change any parts. with 100k miles on them, they should probably have a valve job and maybe change the springs if your planning on running a bigger than stock cam. any competent machine shop will be able to ck them out for serviceability, have them all cleaned up for you and they should ask you what cam you're planning to run (this will determine what type springs to run). and yes, IMO pushrods are a good investment just for good practice sake.

i planned on keeping the stock cam for now. i wasnt even going to get heads for a while but i got a good deal so i jumped on it. if the size of the cam determines the springs then what if i planned on changing the cam in the future. will it be possible get some springs that will be ok for the stock cam and them still have room for a bigger cam down the road.

 

[9T3SVT]

Put them on a shelf in the garage until you can afford to do it right or you're wasting time. Don't put them on with out having them inspected first. I know the standard male thing to do is install the parts ASAP but trust me, I speak from experience. Save up and do it right the first time

 

[thumper460]

Yes... have the heads freshened!! valve job, surfaced flat and NEW springs to match the cam, If your keeping the stock cam, the stock springs should be fine.. but they will need to be tested at the shop and installed at correct pressures.. cool?? Push rods.. why?? stock are fine!! rockers.. Why?? stock stamped steel are fine... just freshen the heads and rock!! ( wow.roller rockers. 5 HP gain for 300.00 isnt really a good $ to power ?? )

Just me..........................

Thumper

 

[legalize420]

thanks. i will take them to get inspected. as far as replacing parts and upgrading i really have limited knowledge of what needs to be done and what would be a good idea to do with the heads now. i was just trying to get some ideas of what needs to be done. i will do some more searching when i have time and see what else i can come up with. im just trying to make this go as smooth as possible. thanks.

 

[legalize420]

what about injectors. i have the 19s on now, but i have a set of 24s in the garage. will i need the 24s on the gt40 heads?

 

[thumper460]

NO.. you dont NEED to, however if you have them ..USE them. you have to remember that the bad ass 5.0 is a "smog engine" and it will love the add'l flow when it needs it.. put them in... cool??

Just me.................................

Thumper

 

[txstang84]

the 19lb'ers should be fine until you get a cam that keeps the valves open longer...you might have to fatten it up a bit with some more pressure since the 40's flow more than the E7's...at least until you get it fine tuned.