Is a Metro Xfi cam marked?

[JackMcCornack]

How does one identify an Xfi cam? One has come available, but the ownership chain has a "The guy told me it was an Xfi..." link in it. I believe the guy who is selling it to me believes it's an Xfi cam, but maybe he's as gullible as I am and surely there's some way to check.

[Bicycle Bob]

There's a 1mm difference in lift, and the reduced dwell also makes the XFI profile look peakier to the practiced eye.

[JackMcCornack]

:-) Lacking a practiced eye, is there a way I can tell? You'd think they'd do something at the factory to keep them from getting mixed up in the field--a number stamped into it, or a peen mark somewhere, or something.

[Bicycle Bob]

The calipers say that my standard one is 40.4 mm to the top of the lobe. Presumably, the XFI will be under 40 mm, but look it up, eh?

[JackMcCornack]

Okay, sorry to trouble you, I was being lazy I guess. I'll go "look it up" somehwere. I'm active on a couple of homebuilt/scratchbuilt car forums and I'm perhaps a bit spoiled, the Locost guys in particular share tech info with abandon, but I'm something of a new kid here on EcoModder and haven't yet learned the customs.

[Johnny Mullet]

There are no markings I am aware of, but if you compare your cam to an XFi or economy cam, you will notice a difference is cam lobe height.

[OldGuy]

The following is from my 1994 metro service manual:

XFI Model
Standard camshaft lobe height is 39.628 to 39.788 mm
(1.5602 to 1.5665 inches).
Wear limit 39.528 (1.5562 inches).


Base and LSI Models
Standard camshaft lobe height is 40.415 to 40.575 mm
(1.5911 to 1.5974 inches).
Wear limit 40.315 mm (1.5872 inches).

[JackMcCornack]

Cool! Thanks, OldGuy, that's just what I needed and my Chilton's didn't tell me.