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Source for flat top pistons 0.020

fireroad

Donation Time
1725cc rebuild is almost complete (Vizard mod, 240z valves, custom rods, KB grind cam) but having a heck of a time sourcing flat top pistol a for 0.020 bore. Ordered from JE Pistons and they have screwed up twice now, the second set are a thousandth off. Who else is out there? Compression is right at 10.1 and I will be running it on AV gas. Thanks!
 
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alpine_64

Donation Time
If you have custom rods... Assume they were set for a csrtain pin height.... So are stock pistons going to work for you?
 

RootesRacer

Donation Time
1725cc rebuild is almost complete (Vizard mod, 270z valves, custom rods, KB grind cam) but having a heck of a time sourcing flat top pistol a for 0.020 bore. Ordered from JE Pistons and they have screwed up twice now, the second set are a thousandth off. Who else is out there? Compression is right at 10.1 and I will be running it on AV gas. Thanks!

When you say a thousanths off, what dimension?

If you are gonna go custom pistons, there is NO reason to use stock dimension rings. J&E made me flat top pistons in 82.5mm which is a great bore for performance rings. I would imagine that 82mm would be pretty common too with an 82.25 in between.
My flat tops run proud of the deck (by design) and are setup for 6" L6 chebbie rods.

One of the key rules when building an engine is to get the pistons first, then supply them to the machine shop and let them bore for the pistons you got, not the ones you wanted...
 

spmdr

Diamond Level Sponsor
Well, this is a timely thread. I'm looking for Alpine pistons also.

It has been YEARS since I bought custom pistons, (Not for an Alpine).

I have dealt with several sources in So Cal.

I have found the biggest challenge has been the sources lack of Retail sales ability.

One of the biggest disappointments was when a shop Bored a block to the wrong size,

with custom pistons in Their hands, THAT took months to get!

It was Shocking how FAST the Shop got the same Piston maker to replace the pistons!


But, YES different Ring dimensions for Alpine pistons!

I'm beginning to think the POOR ring sealing of Alpine pistons is a contributing factor

of their Poor performance!
 

RootesRacer

Donation Time
Well, this is a timely thread. I'm looking for Alpine pistons also.

It has been YEARS since I bought custom pistons, (Not for an Alpine).

I have dealt with several sources in So Cal.

I have found the biggest challenge has been the sources lack of Retail sales ability.

One of the biggest disappointments was when a shop Bored a block to the wrong size,

with custom pistons in Their hands, THAT took months to get!

It was Shocking how FAST the Shop got the same Piston maker to replace the pistons!


But, YES different Ring dimensions for Alpine pistons!

I'm beginning to think the POOR ring sealing of Alpine pistons is a contributing factor

of their Poor performance!

Moly > Cast Iron
 

spmdr

Diamond Level Sponsor
Yesterday I sent a message to "The Piston Guy" looking for Alpine pistons.

So far, NO response....

It's a toss up who I contact next, Ross or Racetec

DW
 

spmdr

Diamond Level Sponsor
I think both J&E and CP have moved out of So Cal.

...not a bad thing for THEM....

DW
 

fireroad

Donation Time
So a quick update: Looks like the machine shop screwed up. The donor block had been previously bored .020 over and all cylinders were good except 1. When they first ordered from JE apparently they did not communicate the cylinder bore and the first set of piston came in stock dimensions. The second time they ordered they said the cylinders are currently 0.020 over and just assumed they would go the next size up. Given how much we have invested in pistons and custom rods already it will likely be cheaper to sell the stock size pistons and current block and buy a different, unbored block. I'm livid because I wanted to go at least 0.030 over, if not o.o40 :mad:
 

RootesRacer

Donation Time
So a quick update: Looks like the machine shop screwed up. The donor block had been previously bored .020 over and all cylinders were good except 1. When they first ordered from JE apparently they did not communicate the cylinder bore and the first set of piston came in stock dimensions. The second time they ordered they said the cylinders are currently 0.020 over and just assumed they would go the next size up. Given how much we have invested in pistons and custom rods already it will likely be cheaper to sell the stock size pistons and current block and buy a different, unbored block. I'm livid because I wanted to go at least 0.030 over, if not o.o40 :mad:
This mean fewer future rebuilds with only a nominal displacement increase.
The larger bore can also reduce the rigidity and integrity of the cylinders due to being thinner.
I would shoot for .020, good first bore diameter.
 

fireroad

Donation Time
This mean fewer future rebuilds with only a nominal displacement increase.
The larger bore can also reduce the rigidity and integrity of the cylinders due to being thinner.
I would shoot for .020, good first bore diameter.

Thanks for that input, that makes me feel better that I didn't miss an opportunity or go too conservative when so much time and money has been but into this project
 

spmdr

Diamond Level Sponsor
Yesterday I talked to Randy at Racetec and Darius at Ross.

Bottom line, stock spec rings and pins are almost extinct!

And my guess is things are not looking good for much improvement anytime soon.


So then the next question is: what ring package to pick? IF I go to a custom piston.


I also talked to Fireroad to clarify his situation, his statement about "...sell the stock size pistons ..."

got my attention.

He has 2 sets of custom pistons.

1 set is for a bore of 3.189

Set 2 is for a bore of 3.2283

It is assumed his subject block has a bore of 3.230

Neither are my Stock size.

BUT, I DID talk about the bore size of 3.228 with Ross, it's a common size for something,

and may be the size I go with a custom piston. DW
 
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