C2 high RPM BLOW-BY

[William V.]

BV

[William V.]

Re: C2 high RPM BLOW-BY

Correction. The car is a C3 not a C2

[Joe R.]

Re: C2 high RPM BLOW-BY

Bill,

What type of rings are you running?

Joe

[William V.]

Re: C2 high RPM BLOW-BY

The rings provided by SCAT are Total Seal part number ST4060. The piston are Keeth Black KB718+.060. Forged

[Duke W.]

Re: C2 high RPM BLOW-BY

He was asking for the type of rings used. Most are made of cast iron, but have a facing on the top ring. Chromium ("chrome rings") was used up until circa late sixties. They offer excellent abrasion resistance, but are slow to break in.

The most common type of OE and replacement rings are molybdenum faced ("moly rings"). They have excellent wear resistance as long as good air filtration is used and break-in quickly.

Some racers just use plain unfaced cast iron rings as a couple of throttle blips will break them in, but they wear fairly quickly, which is not an issue with frequent rebuilds. Some Sprint Car engine builders still use chrome-faced rings due to the highly abrasive dirt track environment.

Rings also come in various widths, tensions, and section geometries. Standard production compression rings are 5/64" wide and have fairly high tension; 1/16" wide "low tension" rings are often used by racers, but are a poor choice for a road engine.

Your problem could be caused by any of the above factors if you are using something other than standard tension 5/64" moly rings, and searching the Web for the manufacturer/part number should yield all the technical details of the installed rings.

Duke