Clay

[Thomas Vaught]

LOL!!!!!!

It will be a while before that deal dies down!

Tom V.

[gofaster]

This is interesting. At 10" of depression on the old SF-110, sucking clay out of the port has not been much of an issue for me.

Several years ago I found some clay at a craft shop that is non drying. The clay hasn't gotten hard yet. The labels are gone now, so that is all I know about it. Once the new bench is done, I'll find out if it still stays put at higher depressions.

For entry radii, I use polycarbonate, acrylic and delrin for rectangular and irregular ports. For round Harley ports, I have a very short velocity stack sort of thing (with a very generous radius) so I can tighten the manifold clamps/bolts to secure it. Testing at 10", the difference between clay, my short stack, and a radiused entry that I cobbled out of an old H-D manifold were negligible when I tested them all on the same head. That in itself surprised me as I expected a gain with the short stack/radius entry.

I like using the solid fabricated entry radii over clay because I know that every head of a particular type that I test is presented to the bench in the same way.

[larrycavan]

Jim

I have several different rubber intake motorcycle carb boots that I ported into the shape of a velocity stack. They seem to work pretty well on Asain bike heads. For the most part, they either bolt on or clamp on....

I haven't had any problem with clay sucking into the bench but I have had a problem recently with it wanting to stay put in exhaust ports at 28" when I used it to fill relatively dead sections of the port floor...

The port shape is funky though. One valve shoots almost dead straight out to the window and the other valve has a significant bend to make before the window.

I have to admit, I was a hold out on higher pressure testing. Things do seem to change when you turn up the juice. I'm now convinced it's the way to test.

Larry C

[Tony]

I have moulded generous intake flares for ports out of body filler. A lump of the stuff stuck to a thin aluminium plate can be held in position with the manifold bolts, and moved from port to port.

[Nick]

The clay is getting better with age. It is now getting harder and stays put. Also my sculpting abilities are getting better too. I can get a 6cfm increase by using clay around the intake port. This flow bench stuff rocks. I think a radius plate is in order, would be a lot faster than sculpting this clay. Not to mention I look like a retard going in the kids section to by clay an Vaseline!!!!!!!! Whats next, baby rattles to to check for turbulence. Sounds Like Larry already has a whistle.