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Old 09-17-2019, 01:31 PM   #1
68Gold/white
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Join Date: Sep 2011
Location: Ark City, Kansas
Posts: 3,307
Re: Green Machine

Congrats on this awesome find!!!

Not knocking ANY of your efforts, BUT there are folks that specialize in Quadrajet Restoration and sell parts for them. Cliffshighperformance.com sells a lot of parts and pieces for these carb's. He sells a throttle shaft bushing kit that comes with it's own self aligning drill bit. I can testify that it does work, I have re-done 4 carb base plates!!!

His book is also very helpful!!! he sells all kinds of parts you cannot even find...
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Old 09-17-2019, 01:38 PM   #2
cariboumarkt
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Join Date: Aug 2019
Location: spokane, wa.
Posts: 28
Re: Green Machine

Quote:
Originally Posted by 68Gold/white View Post
Congrats on this awesome find!!!

Not knocking ANY of your efforts, BUT there are folks that specialize in Quadrajet Restoration and sell parts for them. Cliffshighperformance.com sells a lot of parts and pieces for these carb's. He sells a throttle shaft bushing kit that comes with it's own self aligning drill bit. I can testify that it does work, I have re-done 4 carb base plates!!!

His book is also very helpful!!! he sells all kinds of parts you cannot even find...
Thanks 68Gold/ white, I'm not ditching the Q-Jet, just putting it on the back burner for the time being. I spent too many hours scrubbing the crud off the thing to give up now!
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Old 10-01-2019, 06:37 AM   #3
cariboumarkt
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Join Date: Aug 2019
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Re: Green Machine

With the Carter, er… Edelbrock all spruced up and installed, and the risk of self-emollition greatly reduced, it was time for a tune up! I blew the dust off of the old vacuum gauge and timing light to get a baseline. 17Hg from the handy Edelbrock manifold port… not too bad! I set the idle mixture and then I checked the timing.

Not only did I not find the timing set to the recommended 12° advance, but the thing was actually retarded by several degrees! “Huh, that’s odd” I thought. I loosened up the distributor lock down and bumped that up to a safe +8° as a starting point. With the vacuum advance hooked back up, the engine idle speed shot up by several hundred RPM… another “Huh, that’s odd” moment. I shot the balancer with the light again and “Whoa!”, the timing mark was almost out of sight! Way off my timing marks! I decided to take it around the block and had horrible detonation at almost any load. Back to the shop and under the light I confirmed the proper non vacuum timing was still at +8° but the minute I attached the advance hose the at idle timing shot through the roof! I started backing the timing off and testing for detonation and found that it cleared up when the initial timing was, you guessed it, several degrees retarded.

A quick inspection of the distributor showed a worn out, sloppy mess. I was planning a dizzy upgrade anyway, no time like the present! The helpful folks at the local Motion Auto Supply fixed me up with a stock H.E.I. set up including plugs and plug wires and I finally found time to noodle around with those this weekend. The thing dropped in easy, although the larger cap was a bit tight against the firewall. You’d think with 100 cubic feet of space under the hood of this thing they’da set the engine just a smidge closer to the bumper…

Anyhow, with another quick tune, the initial timing set at +8° the thing now fires up instantaneously, runs much smoother and actually has a little pep when you step on the throttle! Overall it’s a pretty dramatic improvement… I can’t wait to see how much fuel economy improves.

But (there’s always a but), all is not golden. I’m still getting some detonation with an initial timing set at +12°, which seems odd. I’m also still seeing some minor fluctuation of timing at idle, which makes me thing the timing chain might be slacked. And Even with this moderately improved seat-o-the-pants performance found the next weak link… under full throttle acceleration, the motor overpowers the clutch! Hopefully I can adjust that away. Otherwise were looking at a new clutch! No time like the present!
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