Those running a 3.625 stoker with 6.350 rods, what pistons are you using?

Heads are being worked last if that matters, I think that was the idea of doing the heads last after all machining and lower end work. My builder has done many of these, several I know, basically the same build over the years so I trust he has it figured out. Close but not over 9:1 was the target.
 
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It will be difficult to get to 9/1 compression ratio. You can order any size dish and any pin location.

That was one of the reasons I did my piston project. I played hell just getting 8.99:1 with my 4.2 using Speed Pro pistons. With a 22cc inverted dome it makes it easy without all the decking, shaving and custom Cometics.
 
That was one of the reasons I did my piston project. I played hell just getting 8.99:1 with my 4.2 using Speed Pro pistons. With a 22cc inverted dome it makes it easy without all the decking, shaving and custom Cometics.
The bottom line for me is to be able to use the stock thickness head gaskets to avoid cutting the intake. If a person is going to purchase custom pistons,he has the ability to fit the pistons to the engine. This guy has decided to not take advantage of this precious opportunity. Even your shelf pistons would have produced more desirable results,but it looks like he has decided to pay more for less.
 
The bottom line for me is to be able to use the stock thickness head gaskets to avoid cutting the intake. If a person is going to purchase custom pistons,he has the ability to fit the pistons to the engine. This guy has decided to not take advantage of this precious opportunity. Even your shelf pistons would have produced more desirable results,but it looks like he has decided to pay more for less.


In his defense, not many people know about these yet. It was a pain to tear my entire engine down do I could deck it .035" and then another pain to wait for custom cometics at way more money than stock type that are much easier to seal... then another pain to shave my intake... then somehow over the weekend it grew while it sat on the table and I had to shave it again! lol


I wish I would have known to build these pistons before I needed them!! :)
 
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The main thing I don't like about the diamonds is the unnecessary valve relief pockets. Outside of what it does with the frame front or creating hotspots or carbon deposits, It gets VERY thin at the edge of the piston crown.

I wonder why they even have the reliefs, I just got a set of 8.5cr 3800 diamond pistons (Coated) and they looked just like the 3.8 wisecos I used in the other car.Dished, no reliefs
 
Ok, I misunderstood a few things before you go slamming me, again, this is not an area I have much knowledge in, just barely enough to know the terms. I thought the block was going to be zero decked, it is not. The CR would be in the 8.7 -9.1 range, doesnt need to be exact anyway on a turbo motor as a lower CR can be made up with boost, and 3 or 4 points is nothing to be concerned about unless it was NA. There is not going to be enough taken off the deck to warrant any special machining of the intake...which BTW I will be getting Champions heads and intake anyway so having Champion machine them a little to fit better isnt any big deal as they will be doing some custom machining to the heads already is my understanding. Once the heads arrive and the bottom end is together, then it will determine what head gasket thickness to use. May point out, the main caps will get a line bore whihc will also move the centerline slightly towards the top making the piston that much more slightly higher by a few thousandths.
Those pistons did not require any engineering design, or custom coding from the piston maker since these were essentially catalog order, you will be paying a much higher price for a real custom piston, yes they can make anything you want, but it will require their engineering signoff and custom machine coding, easily doubling or tripling the cost compared to an off the shelf piston.
 
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