View single post by Esprit2
 Posted: 06-21-2019 04:29 pm
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Esprit2

 

Joined: 05-01-2005
Location: Minneapolis, Minnesota USA
Posts: 512
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Dakota123 wrote:
Weird... well, one groove looks a bit different than the other two now that I look more closely, so I’m betting it started life as an E. Think I’ll get a degree wheel and try and figure out what it is.Years ago, I bought a 907 cam carrier on eBay. It came with a cam installed that had none of the usual Lotus ID marks, but it did have "Delta" stamped on the back end. I called Delta Motorsports and they said it wasn't one of theirs. So I called Delta Cams, and they also said it wasn't one of theirs. :-/

I used a degree wheel to map it's lift profile, and it's a wild, long-duration cam, clearly not for street use. It's not a Lotus cam, and I've never found any cam spec that matches it.

It's unfortunate that aftermarket cam grinders weren't more diligent about marking their products, and/or obliterating any original marks that might be confusing down the road. And it's unfortunate that, as a group, they weren't more respectful of existing Lotus cam names.

If you don't know the source (ie, from Lotus), "104" and "107" have become as meaningless as "3/4 Race". 'Back in the day', every cam grinder made a "3/4 Race" cam for your small block V8, and they were all different. I would have preferred to have the true meaning of "104" and "107" preserved, but what you get now depends upon where you buy them. Besides frustrating my 'OCD', it makes email-helping someone de-bug their cam timing problems very difficult, since you really don't know what they have.

FYI...
Other LOTUS cams. Competition only, not used for street applications, and no longer available from Lotus.

Cam . . Part Number . . ID Mark . . Lift (inch) . . Duration . . . MOP . . . . Comments
105 . . . A908E0105 . . . 105 . . . . . 0.433 . . . . . 296 . . . . Per event . . Sunbeam-Talbot Rally Engine
106 . . . A908E0106 . . . 106 . . . . . 0.450 . . . . . 320 . . . . Per event . . Motorsport Cam
108 . . . A908E0108 . . . 108 . . . . . 0.460 . . . . . 304 . . . . Per event . . Motorsport Cam

Regards,
Tim Engel

Last edited on 06-21-2019 04:31 pm by Esprit2