Russ K

iTrader: (1)

I've had Yella Terra Ultralite rockers since February 2009 when I installed TFS 215 heads. The TFS springs have ~450 lbs open pressure, and never had a failure. But I always use Royal Purple 10W40 HPS or Mobile 1 15W50 oil. In spring 2013, I installed an EPS/Cam Motion cam and BTR Platinum valve springs with ~400 lbs open pressure as I discovered that the Yella Terra Ultralite rockers might not like 450 lbs open pressure springs.

My cam specs are 234/242/.600/.615/117+2, and it pulls hard to 7000 rpm. And I'm sure I'll never have a rocker failure with the lower open & seat pressure of the BTR Platinum valve springs.

Russ Kemp