GT40p heads with stock HO cam

[90LX5spd]

A buddy of mine is swapping GT40ps onto his stock '90 GT. I know the stock GT40p springs are dicey even with his stock HO cam. Can we save some money buy transfering the E7 springs onto the GT40ps? Thanks.

 

[stykthyn]

That is an extremely bad idea. Do yourself a favor and spend the 150 bones on new springs now instead of new springs, valves, and pushrods later.

The trick flow kit is popular

 

[90LX5spd]

I've seen the Trick Flow kit you mentioned. Should/can we just use the springs from the kit? I've read from several sources that the keepers supplied with the kit are junk and the GT40p heads being installed are brand new Ford pieces.

 

[3uzfte]

I was just in the same boat. I put milled GT40s on my stock H.O block, and was OK on P-to-V clearance, however the stock springs are/were in question and I wasn't going to gamble, so I ponied up and bought the TF kit. I wouldn't suggest using Ford keepers on the TF springs, but that is just me. They are very similar to the stock GT40 keepers, but they are 1 piece instead of the 2 piece design that is seen on the stock GT40 valvetrain. Other than that, the TF springs needed different shims to achieve the same install height, and overall the TF has more strength, and you can tell when installing them. Hope these pictures help.

Locks: Left, Trick Flow, Right, Supplied in GT40 rebuilt kit

Springs: Left, Trick Flow, Right, Stock GT40

Installed: Left, Stock GT40, Right, Trick Flow

 

[90LX5spd]

Cool. Thanks for the pics. It looks as though the exhaust and intake have different installed heights on the stock GT40P head. I assume the Trickflow supplied retainers do away with this as they appear all the same height. Do the Trick Flow retainers do away with the exhaust rotator function and is it really needed anyway?