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Discussion Starter #1
I have a 66 coupe with inline 6, 200cid.

I've had the car for several years now, rebuilt the head shortly after getting it, and while it runs smooth...it's a real REAL dog. No acceleration to speak of, although it'll get up to 90mph and keep up with all the traffic on the highway.

I thought I was having dwell issues so I bought an Ignitor II today, along with the Ignitor II coil. Installation was a snap, and while it does tend to idle smoother and start with a singal click of the ignition, it's still no faster.

Everything is stock on it (carb and what not), and I know every one complains about these cars not having zip, but a 200cid is equivalent to a 3 liter engine, and should have a lot more pep than I'm getting.

One thing I noticed after installing the ignitor ii and hooking up my engine analyzer was that the dwell was reading real low (like 15 deg) at idle instead of the 37-42 deg that the manual called for. The car idles fine, but that reading has me scratching my head. What I'm I not understanding? If I give the car gas, the dwell does raise up. Is that normal? I was under the impression that the dwell was supposed to remain somewhat constant across rpm readings.

One thing I haven't tested is the vacuum advance. The distributor was replaced when the head was rebuilt (3 years ago) and I just assumed everything was okay on that end. The engine has a stainless steel vacuum line and I'm not sure how to test it for leaks, and to see if the vacuum advance is working. Rubber lines are easier in some respects because you can easily hook up a vacuum gauge to them, as well as a vacuum pump to test the advance. Any suggestions on how to do this with metal tubes?

Would the vacuum advance not working cause the lack of acceleration? What else should I look for? Compression is good, I'm not blowing any smoke and my plugs were a reddish brown when I checked them today while regapping them to .04.

By the way, I've got the initial advance set at apx 12 deg with no pinging.

Any suggestions?

Thanks!
 

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I wouldn't worry about the dwell reading, as there's nothing you can do about it anyway. I always kind of wondered how they could talk about dwell with an electronic ignition system anyway, since the definition of dwell is "the number of degrees rotation with the points closed".

To check the VA, remove dist cap, unscrew steel line fitting at carb, stick it in your mouth and suck! It should move the breaker plate in the distributor. Hold suction on it, and it should not bleed off. These engines are sensitive to timing (at least mine is). I always keep advancing the timing until I get pinging under a load at 40-60 MPH, then back it off until it no longer pings. Makes a big difference in how it runs. It'll never be a hotrod, but it gets around pretty darned well.

While you're this far, put a breaker bar and socket on the big bolt holding the harmonic balancer on. Move the crank first one way, then the other while observing the rotor. See how much lag time there is for the rotor to move when you switch directions. If the timing chain is stretched, you can have a lot of "play" in the mechanism, and that could account for the engine running like a dog.

Good Luck!
 

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Discussion Starter #3
I'm happy to report that I found the problem!!!

The dang VA was NOT working, even though the distributor was almost new! Fortunately I saved my old dist., which had a new VA on it, and that one passed the "suck" test. Put it on and voila, performance increased DRAMATICALLY! I'm REALLY happy with the car now! Got the front end taken care of mid week (a three year battle to get it right), got the AC working 3 weekends ago, and now...the car should at least pass a 76 Chevy Vega the next time I see one. ;-)

By the way, the timing chain was replaced when I did the head, along with the harmonic balancer, water pump, etc....everything that was accessible when the engine was apart.

Just need a new muffler and it will be one sweet ride!

I'm embarassed to say how long I've driven this car with no VA! Boy will I sleep good tonight!

Thanks again, DailyDriver

PS,

Mine's a daily driver too, at least until the snow starts flying here in Michigan.
 

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I'm embarassed to say how long I've driven this car with no VA!
That's the beauty of the VMF. I'd be embarassed to tell you how long I drove MINE with a defective VA when I first got it..!! :eek: That's called experience, now I have shared it with you and you just shortened your learning curve, instead of muddling along for years like I did..... By golly, the system seems to be working, thanks to Bob! Just share your new found experience with others, and it will continue to work.
 
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