9165pt0

I have read that the explorer gt40/gt40p heads had weak valvesprings. Some say they are the same at e7 valvesprings. Im not sure which is correct. Im sticking with the stock ho cam, wondering if the gt40 explorer valvesprings will hold up to 5200rpm?

Any experiences with ppl who have used the explorer valvetrain and ho cam is appreciated. Thanks

bluebeastsrt

Those parts will work fine together. no worries.

9165pt0

ok thanks. any idea of how much spring pressure is needed? Im having a machine shop check out the springs for me.

bluebeastsrt

closed 75. Open 215.

9165pt0

ok sounds good. my buddy thought 90lbs and 260lbs for 5000rpm. idk where he got those specs. but ill be sure to check the specs of these to what you stated. thanks again

dawson1112

IIRC the gt40P heads have a higher spec spring on them than the gt40 heads.

9165pt0

the machine shop told me my seat pressure was 80lbs. is this enough for the stock ho cam?