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Needing help from machine shop guys around. Searching for a piston

Nacho-RT74

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ok! I never have got anything easy. So why would be easy now?

I sent my block to get the deck squared. Making the story short, found one piston skirt broken somehow! Pretty sure machine shop did it, but have not how to prove it at this moment

The bigger problem is not really the broken piston, the REAL problem is UEM IS NOT MAKING ANYMORE THESE PISTONS ON ASYMMETRICAL VALVE POCKETS! Now they are SYMETRICAL.

I don't want to deal with unmatched set to the rest of my engine or diff weight deals due this new design. Sooooo please if you have or are related with machine shops getting in stock JUST ONE KB215 +0.020" piston to fifth cylinder ( left side exhaust valve pocket ) NO MATTER IF USED, please let me know to buy it from you!

REALLY PLEASE HELP ON THIS!
 
I don't think the new design is going to adversely affect your engine, as long as it's the same weight, and you have enough piston to valve clearance. The new piston weight should be pretty close to the old design, if not exactly. And you do, of course, want the same height quench pad.
 
Looks like what you have on your hands is a 451, with a 400 block and a 440 crankshaft? And you are using 400 rods at 6.358" length? What is the exact diameter of your piston? I'm guessing that it's 4.360. Is that right? The more info you can provide, the better chance you have of someone being able to help you.
 
Yes!

4.362 is the bore

Being KB215+20 with left exhaust valve pocket ( 5th cylinder ) should be enough info
 
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ANOTHER OPTION FOR ME COULD BE FIND A KB251 PISTON which is the same KB215 but higher step, made to cut at engine needs. Just will cut like the rest of my set!
 
ANOTHER OPTION FOR ME COULD BE FIND A KB251 PISTON which is the same KB215 but higher step, made to cut at engine needs. Just will cut like the rest of my set!
That sounds like the best idea, get the KB 251, and machine down the step dome, to match the other pistons step dome height. You may want to order 2 pistons, just in case. You may need another at some point in the future.
 
UEM doesn't have them in stock either with the old design, so I'm on the same deal
 
somebody dropped the piston/rod on a concrete floor and broke the skirt. i don't think i'd worry about the newer pistons unless there is a noticeable weight difference; and i doubt that.
 
I think I would have chamfered the sharp edge and slapped it back in by now....
 
Yes that's what I will do if I can't find it, but better If I find.

I have even think ( and toward to ) on cut all pistons skirts and have them equalized
 
Yes that's what I will do if I can't find it, but better If I find.

I have even think ( and toward to ) on cut all pistons skirts and have them equalized
I wouldn't worry about doing them all. No more than what's missing off that one, the engine will never know it.
 
Every seller gets individual pieces straight from UEM, and they don't have the old design anymore in stock, just the newer design with equalized valve pockets
 
Gotcha, I guess it's an old picture, because it shows unequal valve pockets.
 
Is the piston I got actually broken which I bought back in 2012
Send us several different pics from different angles, then we may be able to tell you if it is actually broken. From the first pic, it does appear to be broken, as if it was dropped on the cement floor.
 
What is on pic is the broken and missed part. The bottom of the skirt
 
I think I would have chamfered the sharp edge and slapped it back in by now....
Yes, that's what I would have done. You would be surprised at what some guys (including myself) get away with!.....................From the looks of the original picture, the ring grooves appear to be somewhat corroded. Maybe take the rings off and glass bead all of the pistons. Then install with new rings and a freshly honed cylinder.
 
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