Thread: roller cam vs. non-roller short block

Tweet

Come on everyone knows that anything chevy ever made will fit in a sbc and you can rebuild it for $ 36.27.

Originally posted by MIT QUK
Come on everyone knows that anything chevy ever made will fit in a sbc and you can rebuild it for $ 36.27.

chevy. is trying to mix it up a little lately. and that $36 is up to $50.00 now.

Originally posted by lt1s10
i'm talking chevy. i dont know what everybody else is talking about, so just forget anything i said. southerner made me do it.

WEll .............. whatayaknow, I read the small print at the top of the thread FORD I assumed he was talking 302 small block chevy. Sorry about that.

Originally posted by southerner
WEll .............. whatayaknow, I read the small print at the top of the thread FORD I assumed he was talking 302 small block chevy. Sorry about that.

i was thinking chevy. to. all this and we still dont know what "small base circle " means.

Roller blocks have taller lifter bores to fit the OEM roller lifters that are taller than flat tappet lifters. If you get a early block you need to run a small base circle cam so the lifters will be far enough into their bores to stay stable.....or you run the link bar lifters.

Originally posted by MIT QUK
Roller blocks have taller lifter bores to fit the OEM roller lifters that are taller than flat tappet lifters. If you get a early block you need to run a small base circle cam so the lifters will be far enough into their bores to stay stable.....or you run the link bar lifters.

Yes, indeed, You have that correct. Although several manufactures make a retro kit that uses Ford style roller lifters and a spider to keep them located on the smaller base circle cam and they only require the drilling and tapping of two holes.

Originally posted by rficalora
Is the only difference in a roller cam 302 block and a non-roller block the cam that's installed? in other words are the cams interchangeable between the two and what really makes it a roller or non-roller is the cam that's in it?

The sbf has not changed much over the years in overall design but some but there are some small changes to be aware of. If you are comparing early to late the 2 blocks are slightly differant, and there are some modifications that cant be done to early blocks that are used in the late model vehicles, such as: late model blocks used in computer controlled vehicles have a boss by the bell housing that is used to hold a knock sensor which automaticaly adjusts timing when the engine starts to ping (please bear with me the years im going to use will be close but not be right on the money, been a while since I worked at the engine shop ) I believe that the knock sensor boss was put into effect in 1985. also early blocks used a 2 piece rear main seal so the crank shaft and block were differant between early and late model I believe the full round rear main seal went into effect in 1980 and also the provision for putting the dipstick hole into the block came about in the same time frame.
The roller block has 2 holes drilled into the valley to hold down a plate with fingers that hold the retaining clips which keep the roller lifters from being able to spin. If you compare late model to late model roller versus non roller the blocks are identical.
That may have been more than what you are looking for but there it is .

NB

The lifter bores in a SBF roller block are cast taller than the early flat tappet blocks. The tops of the bores are machined flat and the dogbones are held down against it with a spider. The spider is held to the lifter valley with two small bolts.

You can add a roller cam to a non-roller block by using one of the roller lifter sets with the link bars. Another option is to use a roller retrofit kit but these use a small base circle cam to make up for the shorter lifter boors.



--Patrick