GT-40P Heads + B Cam + 1.7s = ??

[Peg8687]

while this combo work?
do i need longer pushrods if so what size?
also will the springs be ok? or do i need new ones too?

Isnt a B cam with 1.7s a 512/512 lift?

Thanks

I'll be ordering all this next week

 

[90mustangGT]

I run the B cam with 1.7's on thumper heads, does well. Is yours a daily driver? The B cam might be a little rough for a DD.

Actually, it's .510 lift but either way I would suggest some stronger springs. I have the Thumper heads with the double valve spring option and I am glad I did it. No valve float, and stock style springs arn't much good over .500 lift.

I have Crane Cam's 1.7RR's, same as the cobra rockers, and I had to get longer pushrods to make them work right.

 

[billheis]

cam & rockers

I running B + 1.7 Cobras + E7s works great. I believe the P heads use same length pushrods. I used the Ford Racing and just about all rocker bolts went 1/2 turn after 0 lash. I use d the Crane spring kit but ran into some problems. Contact Thumper at http://thumperoforangepark.com or PM him though this board. He has a spring that works well for this combo. You might want to send him your heads and let him work his magic on them.
Bill

 

[SwAmPf0x]

I run that combo, no problems with the stock valve springs so far, going to switch to a Comp cam and upgrade the valve springs soon, I needed longer pushrods as well, some P head users do and some dont, wont know until you install the rockers

 

[mike keirstead]

I run that combo, no problems with the stock valve springs so far, going to switch to a Comp cam and upgrade the valve springs soon, I needed longer pushrods as well, some P head users do and some dont, wont know until you install the rockers

Depends on what YEAR P heads the person have.

 

[mike keirstead]

while this combo work?
do i need longer pushrods if so what size?
also will the springs be ok? or do i need new ones too?

Isnt a B cam with 1.7s a 512/512 lift?

Thanks

I'll be ordering all this next week

The B cam is a good daily driver and will make good power with your heads.

It has .510 lift with 1.7s. Usually the stock GT-40 P springs will not support the B cam and 1.7s safely. Some people get away with and may tell you that it is OK to use the stock springs. But I doubt they will buy you new parts when your motor blows up.

Are the heads used? Have a shop pressure test the springs so you know what you have for pressure. Then you will know for sure if you need new springs or not. That is the safest way to do it.

As far as your pushrods go, with the P heads it really depends on what year. Some need different pushrods and some don't. So it is hard to say YES or NO. Best way to find out is get an adjustable pushrod so you can check what length you need.

Also you want to check you PISTON/ VALVE clearance when you assemble the motor.

Here is some good reading on P heads.

http://www.corral.net/forums/showthread.php?s=&threadid=423779