Fan Clutch

[montgomg]

Before I ask my question I did look up the available information on the CRG Reports on this subject and was educated somewhat.
I am looking for a fan clutch for my 69 Z28 which should be an Eaton with a CV stamping. I have located an Eaton clutch with a CH stamping presumably from an SS 69.
Assuming the spacing from the water pump mounting surface to the fan mounting surface is the same or very close between the CV and CH clutches does anyone know the internal differences between these two clutches? Any idea if these differences would render the CH clutch non-usable for the Z28 application? Thanks.

[Gramps69Z]

According to this report, (scan down and read about fan clutches).  It was the length from the water pump mounting to the fan mounting. 


http://www.camaros.org/coolingsystems.shtml

[montgomg]

Thanks, Yes I did read that section before I posted my question. The last sentence of the CRG Report seems to indicate there may be an internal difference in the clutches to account for the RPM ranges of the various engines.
My question remains does anyone know if there are internal variations and if yes could the CH clutch still be used on a Z28 which had originally a CV stamped Eaton clutch.

[lynnbilodeau]

This is the clutch in question.  It is an Eaton, but looks similar to the one in the article labeled as a Delco, except the Delco has somethiing stamped into the metal, where the Eaton is only ink stamped.

[JohnZ]

The small-block clutches were all the same dimensionally (mounting hub face to fan mounting surface), regardless of Eaton (coil thermo) or Schwitzer (flat plate thermo) manufacture; the big-block clutches were slightly shorter. Without the original drawings, I don't think anyone knows the internal calibration differences.

[KurtS]

And I don't know if there was an RPM-capability difference between the clutches...

Kurt (the author)

[montgomg]

Thanks to all for your input. That helps greatly.

[RS_COPO_Canuck]

The small-block clutches were all the same dimensionally (mounting hub face to fan mounting surface), regardless of Eaton (coil thermo) or Schwitzer (flat plate thermo) manufacture; the big-block clutches were slightly shorter. Without the original drawings, I don't think anyone knows the internal calibration differences.

The fan clutch that was on my car when I purchased it was a newer aftermarket Eaton. It is scary close to the radiator. Does anyone know of a proper length replacement I can use for now. I am just putting the engine compartment back together and want to put something mechanically/dimensionally correct in there until I can find an original. Thanks

[BillOhio]

I believe someone had a cv clutch on yenko yesterday in the parts section if you want some good pictures

[RS_COPO_Canuck]

That one is a CV - I need a CZ......but thanks very much for the reply.
I have found a CZ for $750 which I'm mulling over. I need to put an aftermarket one on for now to get it running.