J-spec Pistons

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SLOroadster
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J-spec Pistons

Post by SLOroadster »

Has anyone heard of the specs being different for japaneese market pistons versus the US spec? I sent one of my .060 pistons back to Deves to have a correct set of rings made (I thought the ones I had were too small) and they said that the oil control ring groove was way deeper than the US spec for the same piston. Is someone smoking crack here? My pistons did come from Nissan Japan, but as far as I know a U20 piston is a U20 piston.

At this point, the re-ring job that I thought was going to take about 4 hrs has turned into a huge pain, due to stupid things :roll: . Perhaps I will have a car again next week.

Will
Sorry, I find modern engine swaps revolting. Keep your G, R, or U series in your Roadster!
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Minh
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Post by Minh »

Well it's entirely possible that there are few JDM items that we are NOT aware of.
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spl310
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Post by spl310 »

I could be out to lunch, but is there a possibility that those are H20 pistons? Might be worth it to have him cross reference.
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SLOroadster
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pistons

Post by SLOroadster »

They are flat top pistons, with the correct part # for .060 U20 pistons. The compression rings fit fine, but the oil controls were way (like .25 inch) off. The H20s are dished (I think, I certainly wouldn't use them for a high compression high rpm engine at any rate. They weren't designed for it.)

Will
Sorry, I find modern engine swaps revolting. Keep your G, R, or U series in your Roadster!
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itsa68
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Post by itsa68 »

Sportsimport had been selling both the Japanese U20 pistons and Deeves rings on this Ebay list link, so you might want to give them a buzz.
In the piston auction its mentioned to use their rings for the pistons.(no mention of using the Deeves that they listed).

Here is the link to where I found their listings for item #7909344789 , #7909344460 and #7909367937


http://stores.ebay.com/Sports-Imports-D ... ayZ2QQtZkm

Ray B.
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