The Pontiac OHC Six

[TheSilverBuick]

Re: The Pontiac OHC Six

Damn, just got an e-mail from a guy that has a set of forged OHC Pontiac pistons, but they are standard sized > > I'm definately going to go measure the piston diamter just to be sure, but the stamping is pretty damning :-\

[Monk]

Re: The Pontiac OHC Six

Wow.....looks like you got
your hands full

I thought this build would
be pretty straight forward

[squirrel]

Re: The Pontiac OHC Six

Sounds odd, but I can measure a bore with a tape measure, to the nearest .01". Or a steel rule is even better.

It's easy to see 1/32" which is a .030" overbore

[TheSilverBuick]

Re: The Pontiac OHC Six

I have a fancy dial caliper, I just got lazy about it :P

[TheSilverBuick]

Re: The Pontiac OHC Six

I may of figured out what caused the cam to eat itself. I was looking last night for the oil restrictor in the head to remove it, and simply did not find it. Looking online today, I'm fairly sure I was looking at right where it should of been and it's missing (to be confirmed when I get home). If that's the case, then oil pressure to the lash adjusters was too high causing excess pressure on cam followers against the cam. I hear it's an easy part to forget to install if you aren't familar with the engine. Luckily these are available for $10-$15 (cam followers are ~$9.00).

Last set of pictures on this link.

http://www.webrodder.com/article.php?AID=360&SID=4&CID=

[Scott Liggett]

Re: The Pontiac OHC Six

What's with this rubber glove stuff? Afraid your hands will dirty. haha. ;D ;D

.030 pistons would seize up in a standard bore pretty quickly. Get out your fancy, schmancy digital dial calipers and measure to be sure.

[TheSilverBuick]

Re: The Pontiac OHC Six

I don't have a digital one, I don't want to replace batteries :P

[TheSilverBuick]

Re: The Pontiac OHC Six

Squirrel, Harmonic Balancer question for you (because when I googled 292 Balancer it had your name all over it, LOL!). Looking at balancers, if I can determine if the stock one on mine is neutral balanced, think I could use a 292 balancer on mine and sort out the alternator bracketry later? Some 292's "look" similar. That way I could get an SFI rated balancer. Thought I'd ask you before persuing it too much further.

[squirrel]

Re: The Pontiac OHC Six

Should be neutral balance on all of the straight 6 engines. I think you can even use a small block v8 damper, but they don't have a pulley groove.

post a pic of your damper again?

[TheSilverBuick]

Re: The Pontiac OHC Six

I figure if they will work on the Chevy 250/292 it'll bolt to my crank, it's just a matter of figuring out the alternator bracketry. The only pictures I have online are the ones of it on the 292 crank. The belt cog isn't attached to it.

[squirrel]

Re: The Pontiac OHC Six

the 292 used a thicker one like that, the 250s were generally pretty thin. A V8 damper would stick out pretty far. I think at one time I had single, double, and triple groove chevy 6 dampers. Somewhere there might be a picture.

[squirrel]

Re: The Pontiac OHC Six

here you go. The one that's installed is the 250 in the camaro. The ones laying on the floor are 292 and I think a 194 from an early nova.

[TheSilverBuick]

Re: The Pontiac OHC Six

Just to show some spacial relationships. I had forgotten about the waterpump pulley :-\

[TheSilverBuick]

Re: The Pontiac OHC Six

Are the crank snouts the same as the small block chevy?

[squirrel]

Re: The Pontiac OHC Six

I think so. I could go take more pictures and measure with my fancy schmancy dial caliper.