Port matched 25mm insulator

[Bowen]

So a few months ago I purchased a 25mm manifold mace bakelite insulator and I was quite impressed with the product, anyways had to change the fpr as mine was defective so I took the manifold off and apart and I noticed that the intake runners didn't line up with the ports on the insulator and then again to the lower half of the manifold so I spent a couple of hours on the die grinder with a tungsten carbide bit and ported the insulator and parts of the intake runners until it was a mega smooth transition down each one and man oh man did it make a difference!

So if anybody out there has a manifold insulator and you find that some don't line up spend a little time and you will really get an Awsome result!