Can someone tell me whats the difference between the SBC 350 center bolt VC heads and the side bolt VC heads? I have the center bolt ones on my 88’ K5, just wondering why there different.
function wise they are the same , but ya need a intake from a 87 up head design for it to bolt up to those ,as the intake and v-cover have diff bolt patterns . the 86 and older perimeter v/cover have there own pattern as well . they will bolt up to any gen 1 small block no problem
I’m looking to stay with the same valve covers. Why are bolt patterns different? Are the non center bolt heads vortec heads? Or did they just start casting them different and had to switch to a different style valve cover?
Yeah you need matching intake manifold/plenum. IIRC the manifold mounting difference was that on some heads the bolts went in vertical(like on the 4.3 vortec), while others had the bolts go in perpendicular to the intake flange surface(angle)
He doesn’t want to change the heads. He just wants to know why some valve covers have the mounting holes in the middle and why some have them around the outside.
in 87 gm changed to a 1 piece rear main seal and at that time the changed the v/cover design so they didnt leak as much . at the same time they changed the intake manifold bolt angle of seal at a feable attempt to stop intake leaks . the vortec head is in a class on its own it has no intake bolts in the middle only 2 at each corner of the intake . and like i said before all gen 1 heads will interchange with all gen 1 blocks .
Exactly!
So basically I just have a more up to date design of the valve covers.
ahhhhh ok , yeah you have the newest v/cover design gm had on there gen 1 and 2 heads lolol
Yea I just didn’t know why they made the 2 different style covers. I’m not looking to swap anything on the engine yet, its been running to good.
It’s just new vs. old style. Unless you get aftermarket heads that come setup for either style cover you can’t interchange any parts like John said.