Hey all,

So, after another series of delays, I resumed work on my '91 bird (Although, sessions continue to be periodic, as it's at a friend's house). While removing the valve covers and intake manifold today, I discovered that the engine, at least partially, may not be original...I was under the impression I had a factory L03, but the heads are on top of a flat tappet block...(lame!).

Just curious, were center-bolt heads ever installed on non-roller blocks in these cars? I was under the impression that all 87+ 305's had roller cams from the factory. Maybe the PO slapped all the top end stuff onto an earlier block? Might partially explain why it always ran terrible w/a stock L03 tune (Not to mention, I found coolant in the lifter valley...)

 

The truck engines got the center bolt valve cover heads but did not get a roller cam (until the 1996 vortec engine)

So it could be a full size truck, van, suv engine.

But no as far as the F body cars goes from the factory if it has center bolt heads, it has a roller cam as far as I know

 

Yeah, I had a feeling that it's either a motor out of a truck/van, or an earlier car. I thought most 87+ blocks still had had the provisions for a roller cam though, even if they came with a flat tappet? The one in my car doesn't even have roller provisions in the lifter valley.

Planning on pulling off the heads to get some casting #'s later in the week/this weekend. Will I be able to find the block casting # with the motor still in the car? (Most wiring/accessories have already been removed, making some space.

 

Get the suffix code off the block... Front pass side, on machined pad in front of head. It will tell engine plate, mo, day, year, size, HP, induction, and what car it was installed in.

 

ANY heads bolt to ANY block in the SBC family. ANY goob can do it. Happens all the time; more often than not in fact.

All the suffix code will tell, is what engine and car application THE BLOCK was part of. May or may not bear anything more than a passing resemblance to what THE ENGINE is now.

People slap (or "throw"... any time on this board somebody says "I'm gonna 'throw' {fill in the blank} on my car" I just click the Back button) non-factory combinations together all the time. In fact I would propose that less than 1% of all "combinations" are factory once the heads get changed while the motor is apart, and most of those, are by pure accident.



Block casting # is behind the driver's side head, on top of the bell housing flange. I wouldn't bother with stamping codes.