| Also known as | GAN 25, GAN-25 |
| Listed in parts books | Not catalogued by year yet |
PISTON SET +.020 (63.5mm) T100 1939-57 - 9-1 COMPRESSION - REPLACES 70-3615 CP161 - Use CP29 for 7:1
A +.020 oversize 9:1 compression piston set (63.5mm) for the pre-unit Tiger 100, replacing the older 70-3615/CP161 piston.
This is a +.020 oversize piston set for the pre-unit Tiger 100, sized to 63.5mm and built for 9:1 compression. It's cataloged as a direct replacement for the older 70-3615 / CP161 piston, so if your parts book or a machinist's old paperwork references either of those numbers, this set is what you're after. Ed keeps this one filed under the JRC 5TPU/020 number, with GAN 25 showing up as another form of the same listing.
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Note the catalog specifically flags this as the 9:1 compression version. If your motor calls for 7:1 instead, the listing points to CP29 as the correct set — don't grab this one by mistake if that's your spec.
We don't have much more on file beyond what's in the catalog entry itself. Give the shop a call with your bore measurements in hand before you order, just to be sure the +.020 size is what your cylinders actually need.
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