what is the main difference in small blocks that are producted pre 86 and after 87+?

Dip Stick location,and rear main seal (2 piece vs 1 piece),and I think some of them were roller cams(not sure)!

Dip Stick location,and rear main seal (2 piece vs 1 piece),and I think some of them were roller cams(not sure)!


every 87 and new small block i've come across r set up for roller cam now that dosen't mean every block has a roller cam but u could easly put one in one of these blocks with the right parts. one piece sealis alot better then the 2 piece. and u can't use 86 and older fly wheel and balancer on a 87 and newer. oh yea center bolt valve covers on 87 and up and on the intake the center bolts r strait up and down and vortec engines have no center bolts just 8 end bolts that r also strait up and down

All later blocks were set up for roller cams, but they didnt put the roller cams in trucks till 96.

I assume then if that an 87+ original roller block can easily be a set up for a standard cam with no changes then...

ignore my stupidity, I am just trying to learn...

What is set up internally different on an 87+ block in order to accomodate the roller cam?

Lifter bores/bosses are a lot taller and they're flat on top. Not all post '86 blocks can be fitted with OEM rollers, look for the machined tops of the lifter bores. And yes, you can fit one with flat tappet cam, but I have no idea why you'd want to with new rollers going for $100 a set and cams available for $100 - $150. One bad lobe on a flat tappet cam will cost 4 times that much in machine costs, new bearings, etc.

http://i131.photobucket.com/albums/p306/furygt426/des21.jpg

like this. u can see the 3 bosses in the middle of the valley