81 CIS, throttle plate position?

[Sub8]

Hi all.

I just noticed that when I pull the throttle linkage open, the point at which the metal arm on the linkage bolted to the fan shroud 'bottoms out' gives me about 75-80deg at the throttle plate. Is this normal? Should the throttle plate open closer to 90deg?

Many thanks...

[E Sully]

Yes, you need to adjust it a bit. Many don't realize they are not getting full flow due to linkage needing adjustment.

[Sub8]

Ok, thanks for that......so how do I go about shortening the arm (to get the plate more open) without affecting the closed throttle (plate position). There doesn't appear to be a seperate cam for the closed throttle position?

[timmy2]

Two lock nuts on the arm? Loosen both and spin the rod to lengthen or shorten as needed.
One nut and end is reverse threaded to enable this adjustment.

[E Sully]

I have an earlier car so I can't say exactly where you need adjustment. The linkage can be adjusted at a numerous points. On mine there is a pedal stop at the front cluster to adjust pedal travel, as well as adjusting the linkage joints up front and at the transmission.

[Sub8]

Hi. So I was being a bit slow!

The linkage from the bellcrank, on the shroud, to the throttle body needed to be shortened, in order to open the throttle more. But this also causes the throttle plate to be more open when you release the assembly.i.e at idle.

The linkage from the transmission side then needs to be lengthened to allow the throttle to close more!

Thanks all.