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64-67 Expert
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8,561 Posts
Looks like a good unit. I still have the same dial-back Snap-on light that I got for my birthday in 1983!! Taken care of, they last a long time.
 

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Discussion Starter #6
I asked for that one.
Timing is set @ 6 deg., runs like crap and runs hot.
If it is running at 210 when it is 27 outside this isn't going to work this summer when it is 110.
 

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64-67 Expert
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8,561 Posts
Do Explain, 'runs like crap'. Most 400's that run poorly are running hot, retarded, or both. What cam and where is the cam timing, what water pump spacing, etc. What is your engine vacuum at idle? If it's a hot running turd, my money is on retarded cam timing or ignition timing. Possible mis-installed distributor by a tooth, too. Get us a vacuum reading at idle. With an 068 type cam, should be damn near 18-21"HG.
 

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711 Posts
6 Degrees initial is way too lazy to run good and will contribute to running hot.

Obviously, you want to tune for max advance (36-ish degrees @~3200 RPMs) and let the initial fall where it may. Mine currently falls in at almost 14 degrees @ idle, but I'm running a couple of gallons of 110 octane with each tank of 94.

As GeeTee says, try tuning it with a vacuum gauge and see how close that gets you. It usually works pretty well.
 

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Discussion Starter #10
6 Degrees initial is way too lazy to run good and will contribute to running hot.

Obviously, you want to tune for max advance (36-ish degrees @~3200 RPMs) and let the initial fall where it may. Mine currently falls in at almost 14 degrees @ idle, but I'm running a couple of gallons of 110 octane with each tank of 94.

As GeeTee says, try tuning it with a vacuum gauge and see how close that gets you. It usually works pretty well.
Thanks for the ideas and specs, the engine was rebuilt to run on this crappy 91 octane gas we get out here in Ca. and it has been sitting in the tank for a year so I think I will pick up a fiver of Sunoco 110 @ the parts store up here and put in a couple gallons.
Timing light came today so I need to check that out.
Also the cam was broken in @ 2,000 RPM for 20 minutes and I only have a total of 70 minutes on this engine but with the ice and cinders on the roads up here I can't take it out to test it.
:banghead:
 

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Former Super Moderator
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9,919 Posts
I don't even know were mine is at. Not recommended but I just time it by ear. I back it down till I can't hear any pinging at WOT, then I back it down a bit more. Runs strong and perfect. When I run the race fuel I ramp it up a bit. It almost seems like every engine wants it's own tune.
 

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64-67 Expert
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8,561 Posts
For years, I had to run my '67 GTO at 2 degrees BTDC when I had the stock 670 heads on it. The 92 -94 octane available in the '80's would not support running as advanced as 6 degrees. When I did use race gas and set the timing at 6, it ran great. Went to lower compression heads later on, and was able to run more initial. Your engine will 'tell' you what it wants. Lower compression, better fuel, or a bigger cam allows more initial advance. And, while more initial will give it more grunt out of the hole, it will hurt your top end. It's a compromise.
 

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Premium Member
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774 Posts
Great thread. Thanks to GR----I followed your example and ordered the same one from Summit as I recently discovered the light had gone out in my old one from the '70's. It's a really nice light and the case should protect it. Been 16* here and now ice storm with snow coming. Maybe by Feb, I'll be able to get the GTO out of the garage to use the new timing light on it. Arrrgh.
 

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148 Posts
I have that same Innova light. Watch the cord on the dwell meter, I've whacked mine on the fan once or twice when ai tried to get too close to the balancer. I definitely like the advance feature and tachometer.

Roper - If your gas has been sittng for a year with no stabilizer, you may want to pump it out. Ethanol gas goes through phase separation after about 60-90 days.
 

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Discussion Starter #15
I have that same Innova light. Watch the cord on the dwell meter, I've whacked mine on the fan once or twice when ai tried to get too close to the balancer. I definitely like the advance feature and tachometer.

Roper - If your gas has been sittng for a year with no stabilizer, you may want to pump it out. Ethanol gas goes through phase separation after about 60-90 days.
.


I already pumped it out through the QJet.
:laugh:
I am on my third tank now.
 

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Discussion Starter #17
Sweet. I can see I was a little late to the party. Congrats on getting your engine done and installed. I'm still waiting on mine....
The waiting is the hardest part especially when everything else is done.
Today I fixed the last bug, intermittent charging.
I bought the repro Delco/Remy regulator from Ames and the contacts were all cockeyed.
Once I got them flat and wiping properly and adjusted it works great.
Now that it is dialed in tomorrow I am taking it off the mountain, maybe to The Summit Inn or out towards Indio on the 10.
Time to put some freeway miles on it.
:)
 
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