piston height

[handyman]

I have a problem, when I used repop rods and nos pistons together the piston doesn't come to the top of the cylinder. The cylinders are sleeved back to standard size. This is on a 45" motor. What is the fix for this. Those little motors don't have all that much power and don't want to loose more to compression loss.

[shelbyinparadise]

you are most likely using the early surplus pistons which were low compression (shorter), than later pistons K-type which were taller. Rods should be same length. Older solo motors controlled compression by three different aluminum heads marked 5, 5.5 and 6 with 6 being the highest. Most 1952 and up servicars came with same cast iron head, but they also had several compression ratios. Shelby

[handyman]

Does anyone know what brand of piston is the tall one? The nos is about .095 short.

[shelbyinparadise]

Does anyone know what brand of piston is the tall one? The nos is about .095 short.

V-Twin is listing both pistons the k style has the 1/16th top rings that was used on G, and K from 1952 to 1973, where the WL used 3/32 rings. The catalog is confusing as it may be showing the same pistons with two different ring styles because in the back of classic section it shows piston sets for k models with different part number with -52 style piston pin. I have some originals I will measure and post, the 55 inch K pistons are arc cut for flywheel clearance on bottom. Shelby

[shelbyinparadise]

Sorting through a batch of nos and used pistons There was two different pistons in production in 1952 for K and G models, one using the late style pin and -52 spiral retainers and one having the old style pin and -32 c clip, both pistons are the taller version and after 1956 all G motors used the K height with -52 pins, found 4 variations including 1 with 4 ring grooves. G pistons would have part number ending in -29, -29A or 29B, Both -29A and -29B are the tall K style, while the K pistons have part numbers ending in -52 or -54. Hope this helps, Shelby

[handyman]

pistons

Sorting through a batch of nos and used pistons There was two different pistons in production in 1952 for K and G models, one using the late style pin and -52 spiral retainers and one having the old style pin and -32 c clip, both pistons are the taller version and after 1956 all G motors used the K height with -52 pins, found 4 variations including 1 with 4 ring grooves. G pistons would have part number ending in -29, -29A or 29B, Both -29A and -29B are the tall K style, while the K pistons have part numbers ending in -52 or -54. Hope this helps, Shelby

Thanks Shelby, I think I can go with that info.