Jonsered 630 with jonny 625 piston.

[smokey7]

Pin to top is same skirt is same width. Also there is small windows around the wrist pin boss. Ill grab pics soon. The 630 piston is a full circle with same size and shape of windows included. So my thoughts that i can get better flow into lower transfers due to flow inbetween p&c instead of just through the windows. What do others think. Its looking like i might be getting a used 630 jug with a semi questionable thin ring piston and wonder if using a 625 piston in its place would benifit anytging other then saving the thin ring piston from pissible bang/and hang. Who needs pics incase my wording sucks it make sence in my head as i think i may try it unless knowen issues pop up tgat i dont notice yet.

 

[huskihl]

It'll run better with the meteor style. The full skirt piston was original to the 630, but the added drag and weight of the skirt will slow it down

 

[smokey7]

When you say run better... Are you thinking about additional flow thru the lower transfer? Or the less potential weight and drag from the full skirt on the original? So far for me its easier to find good am pistons for the 625 vs the 630. I alreasy have one running a oem piston. Stock numbers 107 125 68 now at 105 120 77 it runs real good but wonder if its right for this saw as it only does 12500 on the edge of lean.

 

[huskihl]

When you say run better... Are you thinking about additional flow thru the lower transfer? Or the less potential weight and drag from the full skirt on the original? So far for me its easier to find good am pistons for the 625 vs the 630. I alreasy have one running a oem piston. Stock numbers 107 125 68 now at 105 120 77 it runs real good but wonder if its right for this saw as it only does 12500 on the edge of lean.

My 670 had the same full skirt style as your 1st pic above. I changed it to one like your 2nd pic and it gained rpm in and out of the wood and spooled up faster

 

[NCFarmboy]

I have a New West AM full skirt piston in piston drawers. Can't make myself use it.
Shep

 

[huskihl]

I have a New West AM full skirt piston in piston drawers. Can't make myself use it.
Shep

They probably last forever with all the added skirt support...

 

[Motorhead]

I put one of those full skirt 630 plstons in a 625,It seems to have more torque.

 

[smokey7]

I have 2 real nice used oem 625 pistons 1 real nice used oem 630 piston and a new metior 625 piston and a lrb 630 piston. So i got choices. The lrb pistons look very very nice quality im not scared to run them one bit. I had a gulf lose a chunk of the crown on the intake side on a 625 i built. Will never use another i dont think. The ebay seller said no warranty since it was in a ported saw. He claimed it had to snag in a port. Never seen a saw have the crown drop into the intake so i think it was a excuse from him. It was not his fault but he did sell the piston.

 

[NCFarmboy]

I've not heard any bad reports on LLRB pistons. They do have some that nobody else has. Husky 55 closed port piston for ex.
Shep