Crank identification - 3.4 DOHC - Is it better?

[davida1_hiwaay_net]

Are you going to use the wider SBC cam bearings or stock replacements?

Good work so far on the block prep!

Thanks, I appreciate the comment there.

Didn't know SBC bearings could be used. Is there any modification needed for this to work? I'm going to search it now and see what I can find here about using these.

Sincerely,
David

[Superdave]

I used the Durabond coated ones in my 3500, the only thing the shop did extra was add a 2nd oil hole in the front bearing like the stock one had.

[geoffinbc]

I used the same bearings in my current 3.2L. I did not add the second oil hole. But it is easy to do if you want. The Chevy Power manual has some details on modifying the 660. Although it does stop at the Gen II engines since it is an older publication. But when they mention the SBC cam bearing installation they never talk about drilling a second hole so I never did it.

[davida1_hiwaay_net]

Back to the engine build - The machinist isn't done with the cam bearings yet. They are really busy! They are installing SBC cam bearings in the block.

I worked on the heads today, porting and cleaning them. I feel as if the iron head engines can benefit quite a lot from simple porting such as gasket-matching the intake ports and blending / smoothing the valve bowls. I didn't spend a long time on this, maybe 2 hours. Did a similar porting job years ago on a carb 2.8 and it made a very noticable difference.

Before:




After:


Also, as suggested I cleaned up and blended the oil drainback channel - removing casting flash and creating a smooth path for oil to return to the block from the valvetrain.





Valves all cleaned up. Will probably take them to the machinist to get them ground, IF they won't clean up by lapping. There is hardly any wear, just some light pitting on the exhaust valves. The intake valves looked unused after polishing.



I've got to order pistons for this. Thinking about these Sealed Power WH562CP hypereutectic coated skirt pistons. I really like the coating on the skirts. Every one of these engines has scuffed pistons and piston slap; and this looks like a way to avoid it.

They are standard for an iron head 3.1 so the compression ratio should be OK for this build. Feel free to comment as I am open to suggestion; but cost is a factor on this build.

EDIT: I have ended up with 2 threads on this same car, so I'm going to go back to the other original thread at http://60degreev6.com/forum/showthre...l-85-Celebrity for the remainder of the build.

[Guest]

I looked at King Engine Bearings for this engine, and they have the small groove in the lower main insert. I guess that's the lead-in groove. I like that and will probably order those, IF I can get them.

Thanks. By the way, looking at your sig, this engine is similar. I'm using a distributor with MSD but same Code$59 program.

By the way I did not get a 3x00 engine. The top end did not scare me, but the oil pan is totally different, bolts to the main caps and is not compatible with the old school front timing cover. So I got a 1991 model 3.1 engine. I tore it down to a short-block at the yard and they only charged me $90 for everything from block down. I'm tearing it down and it is *LIKE NEW* Very very happy.

Sincerely,
David

Nope, my engine is nothing like what you are doing lol...

Mine is an inline 2.8, a Nissan L28E to be exact, running off the GM EFI.

[davida1_hiwaay_net]

Nope, my engine is nothing like what you are doing lol...

Mine is an inline 2.8, a Nissan L28E to be exact, running off the GM EFI.

That's cool. I see you wanted something tunable and used $59 for it.