Engine hook bolts on manifold

[BULLITT65]

I see a return spring on your engine hook danny, and then on Loyds car no return spring there, but both of your cars have the water neck with a provision for the return spring, I am pretty sure my water neck doesn't have the provision for the spring. Did all 69 Z have that provision? or was this insignificant enough where some had it and some didn't?
Or just early cars had it? (didn't mean to hijack just curious if this has been raised before or noticed)

[JohnZ]

I see a return spring on your engine hook danny, and then on Loyds car no return spring there, but both of your cars have the water neck with a provision for the return spring, I am pretty sure my water neck doesn't have the provision for the spring. Did all 69 Z have that provision? or was this insignificant enough where some had it and some didn't?
Or just early cars had it? (didn't mean to hijack just curious if this has been raised before or noticed)

All 660 thermostat housings had the provision for a return spring, but it wasn't used - the spring was anchored at the REAR, on the spark plug wire support; bad design that accelerated wear of the primary throttle shaft holes in the baseplate, but that's the way it was.

[BULLITT65]

So did the whole production run of 69 Z 's come with the 660 only? maybe i have the wrong one...
( I am not in front of my car just trying to zoom in on a picture of mine, hard to see if it has it or not)

[jims69]

Our thermostat housing has a provision for a return spring.   Concerned about throttle shaft wear;  I added a front spring  years ago.  It doesn't look correct; but the extra spring is easy  to remove.  A slightly different "feel" on the accelerator pedal ; is the only difference during driving.

Jim

[Edgemontvillage]

So did the whole production run of 69 Z 's come with the 660 only? maybe i have the wrong one...
( I am not in front of my car just trying to zoom in on a picture of mine, hard to see if it has it or not)

There is a good CRG thread on the 660 thermostat housing that might help:  http://www.camaros.org/forum/index.php?topic=10971.0