292 Pistons

[Classic v6 GMC's]

I'm sending my 292 to the machine shop later this week and started looking for new pistons and there are 5 different stock replacement options on Summit alone.
Any opinions/suggestions on the following? Any other pistons that are better?
I want to run 87 so that is why I am looking at stock pistons.
Thanks in advance.

https://www.summitracing.com/parts/u...make/chevrolet
https://www.summitracing.com/parts/s...make/chevrolet
https://www.summitracing.com/parts/u...make/chevrolet
https://www.summitracing.com/parts/u...make/chevrolet
https://www.summitracing.com/parts/u...make/chevrolet

[TJ's Chevy]

Originally Posted by Classic v6 GMC's

I'm sending my 292 to the machine shop later this week and started looking for new pistons and there are 5 different stock replacement options on Summit alone.
Any opinions/suggestions on the following? Any other pistons that are better?
I want to run 87 so that is why I am looking at stock pistons.
Thanks in advance.

https://www.summitracing.com/parts/u...make/chevrolet
https://www.summitracing.com/parts/s...make/chevrolet
https://www.summitracing.com/parts/u...make/chevrolet
https://www.summitracing.com/parts/u...make/chevrolet
https://www.summitracing.com/parts/u...make/chevrolet

All those pistons are .030 over just to be clear. Few of them have different compression distances. https://www.summitracing.com/parts/u...make/chevrolet

I'd just go with these.

[Classic v6 GMC's]

Originally Posted by TJ's Chevy

All those pistons are .030 over just to be clear. Few of them have different compression distances. https://www.summitracing.com/parts/u...make/chevrolet

I'd just go with these.

Thanks for the reply!
Yes I was just looking at .030 over because that is a common over bore. I'm going to wait for the machinist to tell me what size is needed.
I saw the different compression distances and dish sizes and that is why I wanted suggestions.
Any reasons for those pistons over the other? Just wondering.

I am building this for my 4x4 so I want to keep the low end torque.
How much would 1.84 or 1.94 intake and 1.6 exhaust valves help?
What about lump ports?
I plan on going with a 4 barrel intake.

[TJ's Chevy]

Originally Posted by Classic v6 GMC's

Thanks for the reply!
Yes I was just looking at .030 over because that is a common over bore. I'm going to wait for the machinist to tell me what size is needed.
I saw the different compression distances and dish sizes and that is why I wanted suggestions.
Any reasons for those pistons over the other? Just wondering.

I am building this for my 4x4 so I want to keep the low end torque.
How much would 1.84 or 1.94 intake and 1.6 exhaust valves help?
What about lump ports?
I plan on going with a 4 barrel intake.

I'm not sure what the stock distance was so I picked the furthest. haha Personally I'd prefer sealed power pistons over those, but you can only get cast aluminum propane pistons from them which would bump your compression to 9.5.1.
With stock compression and a stock cam bigger valves with lump ports won't do a whole lot. 1.84's with lump ports would help for sure, but adding some lift would be the best thing you could do.

Here would be a good cam:
http://www.compcams.com/Company/CC/c...x?csid=58&sb=2

This is a 250 cam so you'd have to have it custom ground on a 292 cam.

4 barrel intake with headers would help to. You'll get better mid range with them.

Really the best thing you could do is bump the compression up for more power, then you would have the low end still. 5-8 pounds of boost would really do it.

[GRX]

The #1437 would be my choice as well.

How would one deal with different fuel pump eccentric location using that 250 cam? Electric?

[Classic v6 GMC's]

Originally Posted by TJ's Chevy

I'm not sure what the stock distance was so I picked the furthest. haha Personally I'd prefer sealed power pistons over those, but you can only get cast aluminum propane pistons from them which would bump your compression to 9.5.1.
With stock compression and a stock cam bigger valves with lump ports won't do a whole lot. 1.84's with lump ports would help for sure, but adding some lift would be the best thing you could do.

Here would be a good cam:
http://www.compcams.com/Company/CC/c...x?csid=58&sb=2

This is a 250 cam so you'd have to have it custom ground on a 292 cam.

4 barrel intake with headers would help to. You'll get better mid range with them.

Really the best thing you could do is bump the compression up for more power, then you would have the low end still. 5-8 pounds of boost would really do it.

Okay I dropped it off at the machine shop and he said we need .040 over pistons.
Can I get .040 over propane pistons? So I would have to run 91?

So if that cam, 1.84 and 1.6 valves, lump ports, 4 barrel and header will make a nice engine then I will do that. Just not sure on pistons.

[TJ's Chevy]

Originally Posted by GRX

The #1437 would be my choice as well.

How would one deal with different fuel pump eccentric location using that 250 cam? Electric?

You can't use a 250 cam in a 292, that eccentric will hit against something and for the life of me I can't remember, OR it was the fact that you Can, but you won't be able to run a cam driven pump.

[GRX]

Originally Posted by TJ's Chevy

You can't use a 250 cam in a 292, that eccentric will hit against something and for the life of me I can't remember, OR it was the fact that you Can, but you won't be able to run a cam driven pump.

You are probably thinking of flat spots on the 292 cam for conn rod clearance. That would be chief concern using a 250 cam.

[TJ's Chevy]

Originally Posted by Classic v6 GMC's

Okay I dropped it off at the machine shop and he said we need .040 over pistons.
Can I get .040 over propane pistons? So I would have to run 91?

So if that cam, 1.84 and 1.6 valves, lump ports, 4 barrel and header will make a nice engine then I will do that. Just not sure on pistons.

If it was me I'd go with a .040 over set of Ross pistons...but those will put you out $620. lol

Another issue is the sealed power pistons are only available in a .030 over bore.

If you can't find pistons you can shave the block and head for more compression. I shaved the head on my 292 .030. Block you'd have to be more conservative with. Any particular reason why you have to go .040 over???

[TJ's Chevy]

Originally Posted by GRX

You are probably thinking of flat spots on the 292 cam for conn rod clearance. That would be chief concern using a 250 cam.

That and I thought there was a reason you couldn't as well due to the position of the eccentric. I'll have to read up on that again.

[Classic v6 GMC's]

Originally Posted by TJ's Chevy

If it was me I'd go with a .040 over set of Ross pistons...but those will put you out $620. lol

Another issue is the sealed power pistons are only available in a .030 over bore.

If you can't find pistons you can shave the block and head for more compression. I shaved the head on my 292 .030. Block you'd have to be more conservative with. Any particular reason why you have to go .040 over???

I can't spend $620 for a driver build lol

I'm going over there tomorrow so I will ask him if I can get away with .030 over. It has a good cylinder ridge at the top so that is why he was thinking .040 to be safe.

[TJ's Chevy]

Originally Posted by Classic v6 GMC's

I can't spend $620 for a driver build lol

I'm going over there tomorrow so I will ask him if I can get away with .030 over. It has a good cylinder ridge at the top so that is why he was thinking .040 to be safe.

"I can't spend $620 for a driver build lol"

Sure ya can! They are a nice set to, I got them for my 292. You can use them as a mirror to comb yer hair in!

Ah ok, Might just have to go with stockers then. Only two sizes I know of for stock pistons are .030 and .060.

[suville]

Sealed power pistons are available in .040 over I ended up with a set Im not going to use, decided to bite the bullet and get the Ross pistons from Tom

[Classic v6 GMC's]

Originally Posted by suville

Sealed power pistons are available in .040 over I ended up with a set Im not going to use, decided to bite the bullet and get the Ross pistons from Tom

The propane or stock style pistons?

[Classic v6 GMC's]

Which lump ports would you suggest?

http://www.ebay.com/itm/HI-FLOW-inta...KVwYcw&vxp=mtr

http://www.ebay.com/itm/T6G1-230-250...hRZ9on&vxp=mtr

http://www.ebay.com/itm/T6G2-Max-Flo...RRXv3F&vxp=mtr

[Classic v6 GMC's]

Well .040 over was confirmed by the machine shop so I guess I will go with these https://www.summitracing.com/parts/uem-1437-040
I guess I can always put a turbo on it.

[TJ's Chevy]

Originally Posted by Classic v6 GMC's

Which lump ports would you suggest?

http://www.ebay.com/itm/HI-FLOW-inta...KVwYcw&vxp=mtr

http://www.ebay.com/itm/T6G1-230-250...hRZ9on&vxp=mtr

http://www.ebay.com/itm/T6G2-Max-Flo...RRXv3F&vxp=mtr

Those 3 are pretty much the same, I'd get the ones in the 2nd link.

Originally Posted by Classic v6 GMC's

Well .040 over was confirmed by the machine shop so I guess I will go with these https://www.summitracing.com/parts/uem-1437-040
I guess I can always put a turbo on it.

Sounds good, turbo would be good with the stock compression.

[Classic v6 GMC's]

Well I have ordered most of the parts except for the cam and lifters.
Pics of what arrived today.

[TJ's Chevy]

Cool!

[Classic v6 GMC's]

Originally Posted by TJ's Chevy

Cool!

Thanks

Today I got the call from the machine shop and he said the head and block were ready for pick up!!

[Classic v6 GMC's]

Pics

Some Stainless Glasspack mufflers also arrived yesterday.

[TJ's Chevy]

This is gonna be sweet! Hope to see some footage soon!

[Classic v6 GMC's]

Originally Posted by TJ's Chevy

This is gonna be sweet! Hope to see some footage soon!

I hope so. I will get a video when I get it running good.
I'm watching for a video of yours running.

[Classic v6 GMC's]

The High torque cam and other parts arrived today so I now have most everything to assemble the engine.

Only things left now is to decide on the distributor, plug wires and harmonic balancer.

[TJ's Chevy]

For the harmonic balancer I went with this:
https://www.summitracing.com/parts/r...make/chevrolet


For the distributor I went with this:

https://www.summitracing.com/parts/d...make/chevrolet

The DUI is expensive....but made here in America.

Here's an alternative on Ebay(It comes with wires):
http://www.ebay.com/itm/CHEVY-Inline...RXtR~4&vxp=mtr

Or you could just get a set of Napa Premium HEI wires for a 70's 292. They are a nice set and are 8 mm.