OEM oversize pistons

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OEM oversize pistons

Postby drbob » Wed Nov 20, 2019 6:34 pm

Anyone know / remember what OEM oversize pistons were available
when they were offered by Isuzu?
Also when dry cylinder (lipped) sleeves are used, Goetze,Kolbenschmidt/Mahle appear to be quality, what about Chinese?,
IIRC Shanghai Isuzu Diesel state that they have the Laystall chrome process in production!
Anyone used these?
Thanks for any tribal knowledge available.
1981 Diesel LUV Sport long bed

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Isuzu vehicle(s): 1983 Diesel LS Long Bed 4x4

Re: OEM oversize pistons

Postby Halden » Thu Nov 21, 2019 9:19 am

I don't know of anyone who has used these. With them being sleeves, they are not exactly structural since they would be dry. My only concern would be quality of the alloy and thickness of the material. Ideally They would be rather thick, and then you would have to machine them down to the spec as when pressed in they can buckle and distort by a couple thousandths of an inch...

I believe 20 and maybe 40 over were available as over size pistons but boy are OS pistons expensive. Cheaper to get it sleeved. Technically safer to get it sleeved too because there is more material there to keep the cylinder walls from cavitating.
It's not pronounced "Ih-soo-zoo", it's pronounced "It-screws-you"
83 LS Long Bed Diesel 4x4
82 LUV Short Bed Diesel 5 Speed 2wd
64 Chevy C20 w/ 283 & 4 speed.
05 Sonata with a standard