Originally Posted by
jld0211
Hi my car is currently at at a tuners having a fair bit of work done just had omex fitted and while mapping they said the piper cam i have at the moment is causing issues at 5,500 rpm that it is bouncing to much and is causing something similar to a misfire and advise i have a newnham cam put on to solve this has anyone had these problems before how good are these newnham cams the car is a erst cheers jay
it is true its down to the new valve springs, old style piper cams had double springs and the new ones have singles and i find above 18/19psi you will get valve bounce which will feel like a top end misfire when mine done it i fitted duplex race springs and heavy duty lifters and had 240bhp .... but the piper cams wear out pretty quick at those figures so an upgrade is needed...
i've heard alot of the guys with newman cams and solid lifters and double valve springs say they are great and get some realy high figures with them.