sumcollegekid

Hey guys,

Anyone know what the factory configuration for throttle return springs was on a '69 427/390hp? Did it have 1 or 2 springs (primary and secondary), what were the spring colors for the Quadrajet, and where did the spring(s) connect?

Thanks,
Sum

MelWff

In 1969 there was only one spring.
https://willcoxcorvette.com/corvette...jet-68-69.html
see this diagram for hookup
https://chicagocorvette.net/diagram_...d=2347&rc=1945

vespaholic

I know this is an old thread but it just helped me out.
Follow up to the above, while a single spring is correct, does it make sense to run a dual spring set up?
Thanks

CanadaGrant

I still use the stock spring setup on my 69 427. They went to a double spring after but am not sure if it was safety or a progressive spring rate. I guess you can use whatever you want but unless you have a big bind problem with the carb it isn't going to stick open even without a spring.

vespaholic

I always thought it was a safety "thing" in case one broke.
Hence, my question.
I did not think of the progressive spring rate option.

CanadaGrant

There must have been something as GM wouldn't have installed an extra spring unless there was a reason but I have no idea why. I just use the old stock original spring and it seems to have lasted without a problem.

MelWff

best of my knowledge it was a safety issue started around 1971