Muffin

I have a line on a 90 4 bolt main block that has a single piece rear seal but a flat tappet cam. I checked the numbers and found the block was used in both a 2 and 4 bolt main and both flat and roller tappet cam configurations. Can anyone tell me,for sure, if the General machined these blocks to accept a roller cam and put in a flat tappet cam or was the roller cam machine work done on selected blocks only? The engine is running and the guy who has it is reluctant to let me disassemble his DD. Can't understand why.

_twisted_

what is the engine currently in?

Pete K

This was common in pick up trucks. Roller blocks had flat tappets from the factory.

Muffin

jd, it is in a 90 Suburban.
Pete, do you have a clue as to the level of machine work? You are correct about the usage. It found its way into a lot of about everything that had a 350. My aim is to build this into to a roller cam big inch small block. I don't have anything else to suck up my time and bucks at the moment. But if I have to get into machining the block to accept a cam retainer I will pass on this one and keep looking.

Pete K

I ran across 3 of these blocks. The cam retainer plate and bolts need to be obtained. Also the spider and 3 bolts that hold it down are also needed. Otherwise it is ready to go. 1 of the 3 blocks needed the spider standoffs(in the lifter valley) drilled and tapped.

JCAIRE2

For a big inch small block you'd be better off starting with a 2 bolt main and having it machined for billet splayed caps. Much stronger than a factory 4 bolt main.

Muffin

JC you are correct but I am not looking for that kind of HP and RPM. My goal is to embaress the next pimply faced ricer that blips his throttle at me while I am on my way to the Social Security office.
Thanks Pete Exactly what I wanted to know. Time to have the torque wrench calibrated.