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JE piston clearance

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Old 11-30-2004, 04:30 PM
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JE piston clearance

With the JE's I bought from Malvern a little while back, he listed a clearance of .030". I brought my block into another shop than originally to get honed, and apparently the previous guy did a **** poor job boring and honing it. There is about .050" of clearance at best, with some of the larger ones at about .060". The guy at the machine shop doesnt seem too concerned, but I wanted to get a 2nd opinion from you guys.
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Old 11-30-2004, 06:09 PM
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Originally Posted by preith
With the JE's I bought from Malvern a little while back, he listed a clearance of .030". I brought my block into another shop than originally to get honed, and apparently the previous guy did a **** poor job boring and honing it. There is about .050" of clearance at best, with some of the larger ones at about .060". The guy at the machine shop doesnt seem too concerned, but I wanted to get a 2nd opinion from you guys.
You do mean .003" ...... right?

As for the bit of extra clearance there really isn't anything you can do about it. I would check to make sure the bore is true and round.

JE pistons do like a close clearance. That is one of the benefits of them. Go ahead if the bore is round and straight, just make sure gap the rings tight. Also be gentle with cold starts. You might have some extra skirt slap while cold. I use an oil warmer to help with that.

The thing I do is a pretty close bore and then send the block to a ProMod builder for the final hone with the bore plate. Good help is hard to find.

Keep us posted,

Alan
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Old 12-01-2004, 06:16 AM
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Thanks Alan, Yeah, I meant to say .003". That's funny you say JE's like to be close, because one of the critisisms I heard repeatedly was the exact opposite. But anyhow, this may have been my saving grace; the pistons look to be in great shape.

After posting this, I decided on sticking with this block, getting it in the car, and in the mean time starting over again on another block, just so I can get rid of those blasted o-rings.

The guys I just took the block to seem pretty good. I've dealt with them before and they seem to be on top of things. The only thing is they do not have a torque plate. But one would think the L-series is a bit more rigid than most V-8's.

I had a falling out with the guy who originally did the block, and this was before I knew about this of course. It's amazing too, since almost all off his work building and preparing complete motors fo guys who race their Z's.
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Old 12-01-2004, 07:52 PM
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Just planning ahead, now the Malvern is defunct, I'm not sure where to get new pistons for the next motor. JE does not list them on their web site. I wonder if they were a custom run for Malvern? Any thoughts?
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Old 12-02-2004, 02:59 PM
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JE available in the UK but it seems a bit of a long winded way of getting them by ordering them here and then sending them back to you. I will try to find out if they have a USA dealer. Cheers ben
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Old 12-03-2004, 04:59 AM
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Originally Posted by preith
Just planning ahead, now the Malvern is defunct, I'm not sure where to get new pistons for the next motor. JE does not list them on their web site. I wonder if they were a custom run for Malvern? Any thoughts?
I would think that you could order them direct. At least call the teck guys and see what they say. You may be able to spec a set out and then use a local vendor to place the actual order.

Dave had some that were semi proprietary. These would be the 86-87mm bore with a 140mm C to C rod. When I did mine I still had to mill for valve clearance. Dave also mentioned one time that you could chuck them in a lathe to turn down the side under the plug @ 20 degrees. So even getting a "custom" you may still need to massage them further for your application.

Top End also has a listing for JE. Some folks use these folks ....... some don't....

A.
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Old 12-03-2004, 05:58 AM
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Thanks Alan, Ben. I already got the ball rolling and emailed JE's tech department. When I asked about the rings it took a loooong time to hear back from them, but they eventually did get reply. I'll give it a week and resend another email. I have tried calling, but I usually get their voice mail, which they've never answered back.

I forgot about Top End. I'll get in touch with them. Yes there are "stories", but I've occasionally ordered stuff from them with no problems.
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