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You may recall that I have been working with a rich carb and exhaust backfire problem for a while. I have a 302 with an MSD dist. speed demon 650 carb and it was so rich that my eyes watered and the exhaust "painted" the rear bumper with black smudges.

The car is running much better tonight and there is no more exahust backfire. The vacuum is all the way up from 8 inches at idle to 15-16 inches at idle! WoW. No off idle stumble although I am still not quite there at the top end.

Here is what I learned about adjusting Crane Gold alum. roller tip rockers. - back off the set screw (allan wrench) in the middle of the adjusting nut so as to unlock the adjusting nut, then back off the nut about 1.5 turuns (this is just to give yourself some slack so you start out with enough valve lash to feel what it is like.). Next, finger tighten the adjusting nut until you can no longer easily turn it with your fingers. Check the push rod by seeing if you can wiggle it up and down just a hair. You should be able to. Then, tighten the nut as far as you can with your fingers. This removes all valve lash without putting preload on the hydraulic lifters. Next, take a open end wrench and turn the adjusting nut tighter by 3/4 of a turn. I get there by recognizing the nut is six sided, then tighten it one "side" at a time until I have tighted it 3.5 "sides". Holding the wrench in place, tighten the lock screw with the allan wrench. Of course, you have to have the cam positioned correctly for each cylinder you are adjusting. I turn the crank to TDC and adjust 6 valvles, to 180 and adjust 4 more, then turn the crank to 280 degrees and finish with the last 6. I have a chart that tells me which valves to adjust at what crank degree, but the chart is still out in the car so I cannot rely that info right now. If anyone wants it, send me a pm.

For timing, I but the blue bushing in the MSD dist. with 2 blue springs. Then I set the intial timing at 13 degrees advanced. This gives me 21 degrees of timing in the dizzy and 34 degrees total.

The carb is rebuilt, with a change in the power valve from 6.5 to 5.5 to lean out the power shot. The primary jets are 66 and the secondary jets are 72. The idle transfer slot shows .020 below both the primary and secondary butteryflies.

I also cleaned the K&N fuel filter and reinstalled, as well as cleaning the K&N air filters.

Just for grins and chuckles at a stop light I moderately revved the engine (2,000 rpm or so) then dropped the clutch. The posi in the 9 inch did its job and both rear tires dropped a little rubber on the road. I can also get a little chirp at the shift to second.

I think the car is just a ittle rich yet and it does run a ittle ragged at the top end, still need to tweak it, but now JohnbPro will beat the car by something under a car length, instead of by a distance measured in zip codes. haha. ::

Well, tomorrows project is to replace the power steering cylinder and control valve, in hopes that I get my steering radius and power steering for right turns back.

Gone but never forgotten
25,239 Posts
but now JohnbPro will beat the car by something under a car length, instead of by a distance measured in zip codes
As long as I'm still beating you, that's all that matters ::

That's great news Ken, and a good "how to" on the valve adjustment. What I do for the 1/2 or 3/4 turn of the adjusting nut is to position my wrench/ratchet perpendicular to the head, then when you turn it, when the wrench is parallel, that's 1/4, perpendicular again is 1/2, and parallel again is 3/4.

Judging from you new vacuum readings (which are higher than I've ever heard from your engine), and the bark of second gear (which I've never heard from your car), it sounds like you're real close. You may actually be beating me now if I don't get that track-lok fixed soon :(
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