[Cliff R]

Believe it or not I purchased all the parts for my Distributor, a curve kit with weights and springs, the adjustable Vacuum canister and a special stop device that looks like a ruffle potato chip for lack of better terms.

JUNK! Those aftermarket recurve "kits" are now and never have been worth two squirts of duck poop. Taking out VA timing with the "waffled" shaped part on the rear screw is just STOOPID right to start with. The travel of the VA should be limited on the OTHER SIDE by controlling when it stops, not when it starts. The springs they supply don't have good tension properties nor are they made of good USA spring wire so go "soft" after placed in service. PM Suntuned and ask him about all that when you get a moment since you don't value my knowledge when it comes to these things.

The Pistons have been installed backwards since 1968 and for a reason that has been authenticated to function in race applications by your peers.

I provided adequate DIRECT experience with doing this and all the negatives that came with it. None of my "peers" provided much more than theory and regurgitated inaccurate information about what happens when you install pistons with the offset in the WRONG direction. That's just STOOPID right to start with and nothing more than an old "racers trick" that never really did much aside from cause piston slap on a cold engine. Since you don't beleive me below is a quote from a very well known authority on these ( Lars) who has written many articles on tuning and other things associated with this hobby:

"Many years ago, I made the mistake of installing some pistons backwards. It did not work well at all, and I ended up doing a teardown to correct it.

The thought that a bunch of yahoos on a Forum think they know more about piston design than the engineers who design pistons is pretty absurd. Even when you have custom-made race pistons designed and built they are of the same basic design geometry with offsets and an oval cam-grind shape to compensate for asymmetrical expansion due to asymmetrical mass. There is a damned good reason the piston designers do not design the pistons to mimic a backwards-installed piston."

The question is:" why do you people say "dot to dot" when that is a Chevy timing Gear installation procedure, "not" Pontiac.

"Dot to Dot" applies to ALL of these engines, Chevy and Pontiac included. As the builder you have the option to put the "dot" on the top gear at either 12 oclock or 6 oclock. I personally think it's easier to put the top gear with the dot at 6 oclock simply because it's much closer to the dot on the lower gear and less likely to get miss-aligned if you had too many beers during the assembly process! Seriously, it is the SAME end result either way as when you turn the engine ONE revolution the dot on the upper gear simply moves 180 degrees and the dot on the lower gear moves 360 degrees.

Despite this thread running on at least 18 pages longer than it should have I tried to help provided good advice from well over four decades of doing this sort of thing, over 20 of it full time logging over 13,000 work orders in my shop (I would say that I did nearly half that many off the books but the IRS might be watching so I'll keep the numbers low). Instead of following my advice you continued to listen to folks who have about as much direct experience doing this as I spent on the crapper this morning. A few have a tad bit more than that, but in any case after all the work you now have an engine that makes so much heat you are unable to get rid of it even with all the cooling system mods in place. From what I've seen here with these engines it is far better to take steps to keep them from transfering all that heat into the jacket water right to start with, than to try to get rid of it. So basically it is better to treat the disease than to deal with the symptoms.......FWIW and IMHO........

[TRADERMIKE 2012]

Originally Posted by Cliff R

Believe it or not I purchased all the parts for my Distributor, a curve kit with weights and springs, the adjustable Vacuum canister and a special stop device that looks like a ruffle potato chip for lack of better term s.

JUNK! Those aftermarket recurve "kits" are now and never have been worth two squirts of duck poop. Taking out VA timing with the "waffled" shaped part on the rear screw is just STOOPID right to start with. The travel of the VA should be limited on the OTHER SIDE by controlling when it stops, not when it starts. The springs they supply don't have good tension properties nor are they made of good USA spring wire so they go "soft" after placed in service. PM Suntuned and ask him about all that when you get a moment since you don't value my knowledge when it comes to these things.

The Pistons have been installed backwards since 1968 and for a reason that has been authenticated to function in race applications by your peers.

I provided adequate DIRECT experience with doing this and all the negatives that came with it. None of my "peers" provided much more than theory and regurgitated inaccurate information about what happens when you install pistons with the offset in the WRONG direction. That's just STOOPID right to start with and nothing more than an old "racing trick" that never really did much aside from cause piston slap on a cold engine. Since you don't believe me below is a quote from a very well-known authority on these (Lars) who has written many articles on tuning and other things associated with this hobby:

"Many years ago, I made the mistake of installing some pistons backwards. It did not work well at all, and I ended up doing a teardown to correct it.

The thought that a bunch of yahoos on a Forum think they know more about piston design than the engineers who design pistons is pretty absurd. Even when you have custom-made race pistons designed and built, they are of the same basic design geometry with offsets and an oval cam-grind shape to compensate for asymmetrical expansion due to asymmetrical mass. There is a damned good reason the piston designers do not design the pistons to mimic a backwards-installed piston."

The question is:" why do you people say "dot to dot" when that is a Chevy timing Gear installation procedure, "not" Pontiac.

"Dot to Dot" applies to ALL of these engines, Chevy and Pontiac included. As the builder you have the option to put the "dot" on the top gear at either 12 o'clock or 6 o'clock. I personally think it's easier to put the top gear with the dot at 6 o'clock simply because it's much closer to the dot on the lower gear and less likely to get mis-aligned if you had too many beers during the assembly process! Seriously, it is the SAME end result either way as when you turn the engine ONE revolution the dot on the upper gear simply moves 180 degrees and the dot on the lower gear moves 360 degrees.

Despite this thread running on at least 18 pages longer than it should have I tried to help provided good advice from well over four decades of doing this sort of thing, over 20 of it full time logging over 13,000 work orders in my shop (I would say that I did nearly half that many off the books but the IRS might be watching so I'll keep the numbers low). Instead of following my advice you continued to listen to folks who have about as much direct experience doing this as I spent on the crapper this morning. A few have a tad bit more than that, but in any case after all the work you now have an engine that makes so much heat you are unable to get rid of it even with all the cooling system mods in place. From what I've seen here, with these engines it is far better to take steps to keep them from transferring all that heat into the jacket water right to start with, than to try to get rid of it. So basically, it is better to treat the disease than to deal with the symptoms.......FWIW and IMHO........

This is not telling me why my Engine is overheated, unless you believe the backward Pistons has something to do with it, too bad I don't have the option to be the first to build this motor to begin with , so I can build it correctly in the first place.

[Formulajones]

I believe your overheating issue is due to multiple things, none of which have anything to do with the cam being advanced 4 degrees. Providing that was actually verified with a degree wheel.

The LSA on that camshaft should be around 113 degrees. Installing it at 109 ICL is only 4 degrees advanced and extremely common on pretty much all camshafts today, in fact most will grind that much advance into the cam right from the start.

The tune is one of the biggest factors that play a roll in how hot the engine runs, and 6 degrees of initial timing is no where near enough. I would suspect the curve isn't where it needs to be and likely the vacuum advance not working properly or in an efficient range. I would address that first before I even thought about moving that camshaft again. That's just for starters. We can address other things once that is taken care of.

[Stan Weiss]

Originally Posted by Cliff R

The Pistons have been installed backwards since 1968 and for a reason that has been authenticated to function in race applications by your peers.

I provided adequate DIRECT experience with doing this and all the negatives that came with it. None of my "peers" provided much more than theory and regurgitated inaccurate information about what happens when you install pistons with the offset in the WRONG direction. That's just STOOPID right to start with and nothing more than an old "racers trick" that never really did much aside from cause piston slap on a cold engine. Since you don't beleive me below is a quote from a very well known authority on these ( Lars) who has written many articles on tuning and other things associated with this hobby:

Cliff,
Interesting how when you have done sometime it is fact and accurate. I and others have posted that we have run the pistons installed reversed and had no problems, but of course that doesn't matter.

Stan