The tip of the racing poppet valve is seldom considered, despite having to withstand relatively high contact stresses. Whilst we can say that the contact stresses concerned are generally low compared to other valve train applications, the relative movement between the valve tip and the adjacent component can be low, especially in the case of overhead cam engines where a lash cap or, more rarely, a bucket follower applies the load to the valve.Even in the case of those engines where rockers...
Up until about five years ago, the standard pushrod outside diameter for a USAC National midget engine was 5/16 inch, costing roughly $6 each. That has changed, according to Frank Honsowetz of Ed Pink Racing Engines (EPRE). Now, he uses one of two Trend 4130 chrome moly pushrod specifications, both with carbo-nitriding that infuses carbon into the material for a better bearing surface. Honsowetz said the 166-cubic-inch Toyota four-cylinder engine they build for use in USAC’s National...
What does it take to build a better valve spring for USAC National Midget use? Frank Honsowetz of Ed Pink Racing Engines (EPRE) in Van Nuys, California cites a long-term relationship with Steve Pound at PSI Springs as his great starting point. “We use PSI springs in everything we do, not just in the Toyota midget engine,” he told me. “We have such a long relationship with them and we are able to work together to advance development of our springs. “I think Steve looks...
In recent articles, we have assessed some of the materials employed in the manufacture of racing valves. This month we will take a break from this recent theme, and take a brief look at some of the surface treatments used on racing valves, perhaps returning in the future to look more deeply at some of them.In terms of surface treatments, we can split these into three basic groups:Coatings, which are applied on top of the bulk materialSurface hardening treatments, which alter the mechanical...
Although Funny Car engines get torn down from top to bottom end between 1000-foot NHRA Full Throttle Drag Racing Series passes, it’s easy to overlook pushrods “because they are that good,” according to 2008 series runner-up and 2009 Countdown to One participant Tim Wilkerson. He’s been using “nothing but Manton pushrods” in his engines for many years citing, “Terry’s got a good product and he’s quick to fix something if it’s...