Tach- Dwell Meter

Airgap dwell is a new one for me. Early Ford specs used to be "Percent Dwell", amount of time the points were closed with respect to the ignition cycle. 90* dwell is close to 100% for a 4 cylinder engine but gitts complicated with 6 and 8 cylinder engines.

Most common is degrees dwell, amount of rotational degrees the points are closed. Most of the time, the dwell is about 2/3's the camshaft rotation. Thus most 4 cylinder engines have a dwell of about 60* outta 90* camshaft rotation. 6 cyls will be about 45* outta 60* rotation. 8 cyls will be about 30* outta 45* rotation.

N.B.....the more degrees dwell, the smaller the points gap and HOTTER the sparkie. BUT TOO SMALL a points gap and ya burns yer points; 'cuz the coil primary electrons will "jump the gap" inspite of the condenser. I always set my points for minimum dwell, (max gap) so I don't haffta be constantly re-adjusting the points gap as the rubbing block wears down closing the gap..... ....Dell

There is no spec given for the side mount. I have been intending to do some research on specs for other Ford four cylinders of the era to see what other Ford distributors are set to.

I have a distributor machine, and one of these days I'm gonna set aside a little time, and chuck up a front mount and a side mount distributor with the points set to spec, and verify what the actual dwell is!

Given the rare and "non-standardized" earlydays use of points dwell, could your front-mount dwell specs be 35-38 deg OPEN? instead of the more commonly used points dwell-time closed? That'd be 52-55 deg "closed" dwell time, somewhat inkeeping with the common 4-cylinder engine tune-up specs nowdays, and more inkeeping with the 0.015 points gap. Justa thought.

I don't have access to a distributor machine, I urge you toodoo yer empirical testing as soon as you can..... ..respectfull, Dell the pointless