Possible stupid question.....

[5.7 hemi]

But why use spiro loxs on wrist puns when an inside snap ring would be easier to install?

 

[RT K_line]

All I can think of would be the tinsel strength or shear resistance of the spring steel compared to a steel snap ring. JMO

 

[5.7 hemi]

Could be, but snap rings are used in transmissions and they take a lot of abuse.

Maybe some of more experienced builders can shed some light on the subject.

 

[cryplydog]

Because they have a strange habit of jumping out of the groove for various reasons. I have never lost a keeper but I have seen it happen too often. Spirolocs are the better deal of today. Smokey Yunick used 2 snap rings per side at 180* out each and also stated that the wrist pin end play had to be no more than .005 with perfect perpendicularity to stay together. George Smith sr. said that they were simply PUSHED out by dynamic forces on high horsepower engines NITRO HARLEYS. I use spirolocs now but I liked using the nylon buttons for many years. I've built and ran quite a few hot rod/race engines and long arm big bore Harley engines over the past 45 years and have always used the very best quality parts and machining I could find, never lost a pin once but Ive seen it many times and I believe its second rate parts, machining, and assembly. As a machinist I can tell you this, if you have a cylinder, rod, or piston or crank journal that are not parallel and perpendicular you will spit the pins out along with what ever else wants to go. Pistons,pins,and keepers/locs have to be machined/fit as a working assy. you just can't use *** pistons with JOJO's pins and chingchong snap rings!

 

[not so famous bob]

Because they have a strange habit of jumping out of the groove for various reasons. I have never lost a keeper but I have seen it happen too often. Spirolocs are the better deal of today. Smokey Yunick used 2 snap rings per side at 180* out each and also stated that the wrist pin end play had to be no more than .005 with perfect perpendicularity to stay together. George Smith sr. said that they were simply PUSHED out by dynamic forces on high horsepower engines NITRO HARLEYS. I use spirolocs now but I liked using the nylon buttons for many years. I've built and ran quite a few hot rod/race engines and long arm big bore Harley engines over the past 45 years and have always used the very best quality parts and machining I could find, never lost a pin once but Ive seen it many times and I believe its second rate parts, machining, and assembly. As a machinist I can tell you this, if you have a cylinder, rod, or piston or crank journal that are not parallel and perpendicular you will spit the pins out along with what ever else wants to go. Pistons,pins,and keepers/locs have to be machined/fit as a working assy. you just can't use *** pistons with JOJO's pins and chingchong snap rings!

I lost 2 snap rings on one of my hemi`s back in the day, u won`t loose a spirolock ! wristpin dragging the cyl. wall ain`t good !

 

[dieseldazzle]

I'd be willing to bet spiro locs would be lighter than the equally sized snap ring.

 

[5.7 hemi]

Well now I know, good info!!