How much lift can stock gt40 heads/springs handle?

[project67]

just wondering how much lift before coil bind on stock gt40 valvetrain.
thanks

 

[Supercharged306]

Check the pressure with a Intercomp valve spring seat pressure tester. This you can do with everything in place. To many people change camshafts and do not check spring rate. I drag race and I check my springs after every race. Now I think you should be safe in the .512 or you might get .550 but don't push it.

 

[mob]

Stock gt40 valve train isnt even enough to handle a stock mustang cam. If you are not using an aftermarket cam or INSIST on not upgrading the springs even with a new cam, use the stock e7 valve train. But for 150 bucks for the trickflow kit that you can install yourself its worth it.

 

[project67]

ok, not sure i understand. the stock e7 heads/cam had less lift than the cobra cam w/1.7 rockers, right? but you are saying the e7 springs are better? if the gt40 springs wont work i'll get some trick flows but i was just wondering how much lift they will accomodate. i run an x303 with my aluminum gt40 heads with the springs that came with them with no problems. i guess they are not the same springs?

 

[mob]

Well I guess it wou ld help to know if you are talking about aluminums or cast iron. I was talking about the explorer gt40 valvetrain.

 

[Vinnietbird]

Use a quality set of springs.I have an extra set of Trick Flow springs in the garage.

 

[project67]

these are gt40 heads, not gt40p heads.
and vinnietbird, how much for the tf springs?

 

[drk]

I'm getting my 40p heads installed next week. Using my stock e7 valvetrain and stock HO cam. Will add goodies later down the road, but just want the heads in now.

 

[drk]

Update: Guys at my shop say HO valvetrain is better than 40p valvetrain... However they said not to run really any type of cam other than stock.