How To Identify Aftermarket Cams?

[DanShirts]

I bought a second hand rb20. The seller says it has "264 pon cams" in it. But they look like stock cams to me. They don't have any casting numbers, or stamps, or serial numbers, or anything. So I went and opened up my friends rb20 that I KNOW has aftermarket cams. His look like stock cams too, no markings at all.

How can I tell what I have?

[MrStabby]

Do the poncams have a different lift to stockers? If so you could measure the lift and see if it matches the poncam spec.

[DanShirts]

My cams have 8.25 mm lift. I think that is stock lift. Can someone verify that?

[DanShirts]

I took them to a machine shop. I measured wrong.. they are 8.5mm lift.

Stock is 7.80 mm lift 240 duration. Mine are 8.5 mm lift 256 duration. So it looks like I have Tomei poncams (or copies).

Factory cam specs: http://www.tomei-p.co.jp/_2003web-catalogu...haft-specs.html

Tomei RB20 cam specs: http://www.tomei-p.co.jp/_2003web-catalogu...4_cam_RB20.html