Hi guys, im in the process of fitting some hd cat cam valve springs in my 20v blacktop head, the new valve spring wont sit in the recces that is designed for the spring, they are 2mm wider then the oem spring. Looking around the net they all seem to be around 20-21mm wide. am i going to have to mach...

The crank is standard, the rods are the same height and so are the Pistons except being higher compression so the top domes out more but they have bigger cutouts to compensate.

Hi guys, I'm Jay from the east of England uk, I race Westfield kit car in a sprint championship and the car has a 4age 20v engine bolted in. I am currently building up a blacktop with the following spec- 12.1 Pistons with Mrp rods, cat cam 291 11mm cams, toda gears non vvt and a steel 0.8mm gasket. ...