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Discussion Starter #1
I finally got my b234 je forged pistons with special coating to increase velocity and lower friction and since its similar technology nascar uses, I should be able to beat the livin crap out of em without breaking them.

Now if I can only figure out how to locate all the end gaps at the same time, I will be set. I did not know it, but you set your top compression ring end gap up to the type of appication or power you will be making. Na cars have a tighter gap, turbo/supercharger, more gap or less tight, if you are nitrous racing, it more than doubles you're gap, much looser...

I settled on in-between street/strip turbo and full on racing nitrous...

John
 

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Yet again you have set the bar John. I like you because like me you don't want to do the normal thing. I don't want to have the power you do(I'm lieing) but I have things I want to do that are not part of the perscibed tune. I am glad that you are here to be a guinea pig for everyone.
 

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Discussion Starter #6
Castor Troy said:
how much were those pistons john?
They are about 650.00 with the coatings and I think 560.00 or so without the coatings. I guess je had never done a b234 forged piston and I had to send them one so they could spec it out and make some for me. Now there is a part# and they can make em for you...:cool:

John
 

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John Z Williams said:
They are about 650.00 with the coatings and I think 560.00 or so without the coatings. I guess je had never done a b234 forged piston and I had to send them one so they could spec it out and make some for me. Now there is a part# and they can make em for you...:cool:

John
:cheesy:

Mine should be here Friday.

I ordered them the week they were being spec'd....now I know why it took so long. :cool:
 

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Discussion Starter #11
Yea, I sent them out about 5 weeks ago... Here is another picture. They should perform well:cheesy:

They look better in the block...
John
 

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Wow, those look sexy inside that block. What are those smudges on the head of each piston? they look like scratches but I doubt they are.
 

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Discussion Starter #16
No scratches, the pistons are numbered and the arrows are for orientation. You have to set the top compression and second ring with the gaps up 180* from each other and the pistons have a small half hole on the back-side of the piston, must be for oil squirter clearance on the stroked block.

They were marked to make sure the right piston went in the right hole and in the right direction! I put each top ring in each cylinder and flipped some around until 3 of them were the perfect end gap for turbo-charged pressures. I had to take about .003 off one of the top rings because it was way too tight. Each ring was set-up for a particular cylinder bore, so #1 was not right for #3 and so on...

Many race engine builders will order their rings over-sized so they can file them to exact perfect end gap specs. Na engines want a tighter ring gap, turbo strip/street is a little looser and full on nitrous racing engine is more than double my gap for extreme cylinder pressures.

I settled at just a hair looser than turbo/ street/strip. It should be perfect for a 50hp shot of nitrous or nitromethane;)

John
 

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John Z Williams said:
Each ring was set-up for a particular cylinder bore, so #1 was not right for #3 and so on...
Did you have the block bored while the pistons were out?
 

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Discussion Starter #18 (Edited)
No, had the block checked 6k ago and it showed basically no wear, it was on the bottom end of the wear scale and the rings were not even broke in all the way yet on the used block I bought. I chose to have the block honed at the machine shop at that time.

It still had a nice cross hatch in the cylinder walls and I just gave it a light hone, about 4 strokes per hole to scuff them up a little.

Cylinders can be out from one to the other even after a good hone and if one cylinder is out .001, you multiply that by Pi 3.14 and it can be as much as .003" so its a good idea to fit each new ring into each cylinder and check the end gap. 3 of the rings were very close and one was too tight. I put each ring in every hole until I got 3 of them to match the recommended specs. So bore or 3.54 x .0050 = .017" for turbo-charged cars. I made the top compression ring match those specs. I had to file one of them to meet specs.

John
 

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Looks nice John, I feel like I am playing catch-up with you. I just put my rings and pistons in my 2.3L last weekend. But my ring gap came out to .021”, which is the top end of the Haynes manual specs. My 2.3L 9000 engine had 90,000 miles on it but did not need any machining, just a hone. The engine machinists were impressed it was in such good condition. Hope to start my swap on Tuesday. When do you expect your piston swap to be finished?
 

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Discussion Starter #20 (Edited)
Yea, that is what my machinest said too, he was impressed at the virtually no wear on the cylinders. He said no reason to bore it over, that just gives you more times to rebuild the engine!

I had it wrong, there was an exta o in there... It was a minimum of .015" for the end gap and for street/strip turbo/nitrous it is bore 3.54" x .0050" = .017"

That is what I set mine up at .017" or 17 thousands. Just a little less than the .021" that you set you're car up at... That makes more sense;)

HMMM, my rings are set smaller than you'res... I hope its enough! They give a minimum of .015", so I am .002" larger than that, I hope its enough...:cool:

John
 
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