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stock distributor vacuum control/ vacuum advance
My 351c 2V has A/C, and the gigantic compressor and brackets to go with it. I tested the stock vacuum advance can, (with a slightly curved actuator shaft extending into the diz) and found it wasn't moving with vacuum (either manifold, carb, or my face), so I decided to replace it.

My FLAPS had one (eventually) with the correct actuator shaft, but the thing is large, really large, and it won't allow me to time the engine correctly, and with a small enough turning radius because it hits the A/C brackets.

So, I don't have a service manual for this car yet, and I also don't know where the old one is anymore to find a part number for the one that will actually turn in the space allowed.

Anyone have the Ford part number handy for the original, and maybe who carries it, even if it's only available from a Ford dealer? My FLAPS do not, yet. I already replaced the points with Pertronix, and do not want to buy an MSD etc., so.......any help?

Thanks in "advance"!

.jpg   dd190.jpg (Size: 34.3 KB / Downloads: 205)

Auto trans, single port: Part number: C5AZ-12370-A, Motorcraft sales number: DD190

anyone know where I can get the spring, port, etc., that screws into it for the vacuum line....if it doesn't turn up in my garage somewhere.......
Solved. 180 the Diz
OK what is FLAPS? I don't want to look like an idiot but I don't know that acronym.
It sounds like the distributor was installed 1 or 2 teeth off from where it should be. The gear on the distributor and the gear on the cam need to be properly "clocked". Not like a Chevy with just a slot. Not sure what year you have, this is for a 1972 351 2V.

The vacuum advance units that I have in my 351C 4V cars are identical to what Chuck posted; should apply the same to 302's as well.

In the worst of cases, you can try timing the distributor one tooth off to get the vacuum advance canister pointing away from the A/C bracket while maintaining proper timing. You may or may not be able to achieve this depending on your upper radiator hose location. If you're already off a tooth or two, find the proper spot for your distributor first, then start experimenting.

Incidentally, where is #1 on your firing order right now? That yellow car in my signature had been kludged together by a bunch of idiots who had the timing off by 157.5 degrees (one plug short of 180) and had it set to the firing order of a Windsor, not a Cleveland (they also wiped a brand-new cam and lifters by running it with no assembly lube, bent four pushrods as a result, installed the wrong thermostat, and stripped some threads in the Holley carb. That's not even including the "bodywork" that's over this car, but that's for its own thread). Not that you did any of that, but I now check every unfamiliar 351C for just that before touching it.

As for vacuum advance adjustments: In the worst of cases, mark the distributor and block at proper base timing, rotate the dizzy clockwise every time you need to slide that Allen key inside the unit to adjust the advance, bring the dizzy back to the mark, and test.

Be glad our brackets aren't that bad - late '70s 400's and 351M's with Delco A6 compressors make it next to impossible to get to the advance units. I drilled a hole straight through the bracket to access the advance on my '78 400; never regretted doing so.

mweeps;186532 Wrote:OK what is FLAPS? I don't want to look like an idiot but I don't know that acronym.

Friendly local auto parts store.

Or, if you happen to think your local auto parts store are idiots, you may substitute the F-word of your choosing.


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I have a stock 73 h code with AC and would be willing to post a pic if you think it will help.

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Yep, mine is a 351 2v with the house-sized AC compressor RPM Air intake mani and a 600cfm edelbrock. I stabbed the diz with #1 @ TDC. and the timing gets just close enough to stay running, then I run into the compressor with the back of the vacuum can, so it's not quite right. I am using the Cleveland firing order and wire map, thanks for asking. Wink Won't grind off the back of the vacuum, or the side of the compressor just on principle, so I may opt for flipping the diz 180*, though it will look kind of goofy.

I should probably try to stab the diz the right way again, since I had it out once again to re-prime the oil pump after replacing the rope seal RMS. and maybe I messed things up that time. I had sweat in my eyes...yeah that's it, I had sweat in my eyes. We'll see. I'm going back through the torque on all the FE bolts and adjuster cams on the front end to see what I missed when I replaced the lower arms and upper ball joints, sway bar bushings and pins etc., first.

After chasing my portable garage and shade canopy around in the wind and repairing things this morning I haven't had time to look at the diz again. Thing runs pretty good really, even with me working on it though. Pics are always helpful, Luke. Anytime you can. Thanks for all your help guys. A lot.
This not a stock vacuum advance but, the relative orientation of the of the distributor to other components is the same. Chuck

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I had the same issue on a '73 I had a while back. I just moved the distributor gear one tooth over so I could center the vac advance unit in the space available. You'll have to put a socket on an extension and move the oil pump drive shaft a little as well, so the distributor will drop back in. Trial and error. Use a little silicone or something on the socket where the extension attaches so you don't leave the socket on the oil pump shaft when you pull it back out.

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