'74 ZO7 identification??

[Mel Goff #33968]

My '74BB coupe has the FE7 (Gymkhana Suspension) option. It's also equipped with the 3:08 rear and M21 close ratio trans. After receiving the restoration/spec package from GM that's been offered, I discovered something of interest. From what I am reading in this package it seems that the combo of the LS4 (or L82) 3:08, M21, FE7 (which was included with the ZO7 option)...might just identify this car as a ZO7: 1 of 47 made. How can I tell if this car has the heavy duty front & rear brakes that complete the ZO7 'off road suspension and brake package'?

Other options on the car as follows:

J50(PB) C60(AC) C50 (rear defrost) no PS or tilt tele

Mel Goff #33968

[Joe L.]

Re: '74 ZO7 identification??

Mel-----

I can virtually assure you from the information that you provided that yours is not a Z-07. That's because if you have J50 power brakes, you could not also have J-56 HD power brakes which are part of the Z-07 package.

In any event, you can check for this option literally at a glance. J-56 HD front calipers will have three readily distinguishing characteristics. First, they will not have the top center bosses for the single caliper pin which retains the brake pads. Instead, they will have 2 long cotter keys at either end of the caliper pad opening which retain the pads.

Second, the brake pads will have a "turned over" upper edge.

Third, the front calipers will have an extra cast ductile iron support brace which attaches between the caliper and the spindle bracket.

Actually, you can just take a glance through the slots on your front wheels to see if the upper center-mounted boss is present for the caliper brake pad pin. If it is, you don't have J-56 brakes and, consequently, you don't have Z-07.

Of course, all this assumes that nothing has been changed or modified on your car with respect to brakes or other components. If things have been changed, "all bets are off". However, if you have some documentation which shows that your car is equipped with J-50 power brakes, then I think the question is answered without further ado.

[Mel Goff #33968]

Re: '74 ZO7 identification??

Hi Joe...

Thanks for the heads up on my question. I should have worded my post a little differently regarding the J-50 power brakes. I do have power brakes, however since the build sheet was destroyed prior to my ownership of the car, I just assumed they were J-50. Until your reply, (and most informative info) I was not aware of the RPO J-56. So.....guess I'll just have a look at my calipers as you suggested and see what I have (sob)...maybe, just maybe I might be lucky. Yours, along with other members' knowledge and willingness to help guys like me, is one of the many reasons I joined the NCRS.

Thank You...Mel