Does anyone use gapless rings of 4g engines?

We started using Manley with gaplles a year ago on Subaru engines and they work absolutely great!

What does the GURU's say?

 

im not a guru but i did look into them and emailed topseal. they said that the second ring is the only one they recomended for gapless. the readon was because of the high boost that our cars run and that because of that we need to allow some blowby of the first ring. i looked for the email but i must have deleted.

 

found the old thread with the email in it.

https://www.evolutionm.net/forums/ev...ings-4g63.html

 

We use the gapless on the second grove.... what I like:

Less blowby
oil stays clean for longer... dont smell the fuel in the oil so quickly.

 

I was chatting with a fellow tech and V8 guy about gapless rings earlier today. He opted to stay away from them due to the additional head work required. His builder said they would have to run tighter clearances at the valve guides due to amount vacuum the gapless rings create. Something I never thought about.

 

We run stock subaru heads... no work done on head of any kind.
Maybe its only on some V8 engines.... maybe small pistons dont pull that much vacuum....

 

I dont know about your car but the little pistons in my 05 MR pull 20" of vacuum at idle on stock cams at 850 rpm.

:-)