Originally Posted by F-BIRD'88
My 406 screams with my vortec heads on it.
revs right up to 6700rpm. pulls like a frieght train. well past 6000 rpm.
The vortec heads are ported but not max ported by any means.
The solid roller cam that you have will work really well in the 400 with your vortecs.
re valve lash:
I trust you were not trying to set the lash "hot".
Its a lot easier to set the lash "cold" a lot more pain free.
You won;t hate doing it either.
Set the lash cold about .004" tighter than the hot lash spec.
I'd reconsider using that cam in your 400 w the vortecs. IMHO it is just right for your 400 w vortecs.
Ap72 has no clue.
The Hyd roller you got is just dandy too. Just not my preference.
These cams are just right.
If you liked the vortec heads on your 350, you are going to really like them on a 400SBC.
Use a -18cc dished piston on your 400 for pump gas compatability with 64cc heads.
A flat top piston 400 with vortecs will need about a 100 octane fuel to keep it happy.
A bit much for pump gas.
the old cam was flat tappet and it wiped a lobe. I was lashing cold, but its a pain in this truck while basically sitting on the motor. The old truck had no fenderwells so i could sit on the tire and go through them very easily. I went hydraulic because my springs were too weak for a solid roller, and i read many horror stories of cheap roller lifter failing with street use. pressure fed lifters are alot of money.
with my intake valve closing at 74 on the new cam i figured i could up the compression to 11:1.. i dont remember the intake closing on the old cam but with a 102 installed ICL it was trapping over 200psi with no pump gas issues. I always spiked the fuel before races, but i did plenty of street flogging on pump 91. always had 32* total timing. I always figured the stall speed and tight quench made it more forgiving