KJL

I see them advertised but not sure what the advantage is for a street vehicle.
I also have been swaping between points and the Pertronix conversion unit. Car seems to idle better with the points.

Alwyn678

I would leave the points alone.(not sure of the benefits of dual points however)...My car idles Super with points but the Pertronix Ignitor II left me stranded :sad:

2ND77

The idea behind dual points distributors is to stop the points from floating. They did this by having 2 sets of points...each only closing half the time...in other words...instead of a single set of points closing for each fire of a spark plug...the 2 sets of points would operate every other fireing. So...the points dont open and close as fast...and dont float. These were very useful in very high reving engines. I dont think for a street use...they are really nessesary. I have one in a 67 Firebird when I was in Highschool...and there was no noticable difference from the single points I took out. Just 2 sets of points to buy and set...(which if I remember right involved a matchbook to keep one set from sparking while I set the dwell on the other...lol. Anyway...thats one explaination...hope it helps.

Ron

kellsdad

It's been many years since I owned a 72 Vette LT1 with a dual point distributor. As I recall, that engine redlined at about 7,000 RPM and I remember replacing or adjusting the points periodically to be able to reach that RPM. As for whether or not they're useful for everyday driving - it depends on whether or not you routinely rev your engine high enough for the points to become the limiting factor in engine performance. If point float is not now a problem, I see no reason to change.

ram82fire

There are two types of "point " systems ,,, one type used two sets of points and a pair of coils . The advantage being double the saturation time for the coil windings . The other type used two sets of points and one coil to increase dwell time . One set closed the circuit and although both sets are actually closed for a period of distributor rotation ,,, the other set would open the circuit . The ones that would open the circuit and thus trigger the coil would tend to pit or burn much more than than the ones that closed the primary circuit . These distributors also had a longer dwell period and used large capacity condensers [so big they were fit on the exterior of the dist body] This is turning into a history lesson and some folks are figuring out how old I must be !! If you want more info just shout . :crazy:

Racer16k

If your having problems with your points floating there are better points with stiffer springs available. Also have you ever used "the piece of vacuum hose behind the points trick"? I thought the idea behind dual points was to allow the coil to charge longer, not to eliminate point bounce. On my Cobra Jet motor the point cam was different to work with the dual points.

lars

KJL -
The dual points allow higher redline rpm with better coil saturaton. Most dual point distributors did not have a vacuum advance control unit, since they were intended for racing. A dual point setup is not the best way to go for a street-driven car.... you can get outstanding performance throughout the usable rpm range of your engine with a good quality set of single points by simply setting up your ignition curve correctly. We held the SS/KA National Record with a single point, stock GM recurved distributor with an MSD6A unit and a Mallory coil. Don't knock the points...! As far as the PerTronix goes... you'll get equivalent or better performance from the points. I have a box full of PerTronix and Unilite setups that I've pulled out of Vettes and GTOs to gert BETTER performance by using good points.

yellow 72

I replaced a stock dist. that has a Unilite conversion with an Acell dual point, tach drive, *with* vacuum advance...wouldn't trade it for any electronic piece :cheers: I guess I just have to justify keeping my old dwell meter :lol:

ram82fire

The point that lars makes about single points is so very true ! Running the dual setup was a maintenance PIA . There are a great deal of automotive electronic gadgets sold on the market , the majority of these products are not really necessary to make your car run well . There are a lot of hot cars around running on points !

Wrencher

I run a full mechanical progressive dual point in the BOSS (7200 redline), but a regular set is fine for the street in most cars. I run points in all my old cars.

Hans

HWY 9 - Z06

I run a dual point distributor out of a '63 in my '69 small block. the idea behing the dual points is to give you a longer dwell time, charging the Coil longer for a hotter spark. I drive my car everyday, about 80 per/day. as long as you go with good points(i use accel) you really dont have to mess with them much. if you use cheap points, plan on adjusting them weekly and replacing them monthly. i change my points every 4-5 months. i did notice an improvement in running from my original distributor, but it may have just been worn out. Points won't leave you stranded though, as long as you have an extra set and a matchbook. tune up spec for a '63 distributor with dual points is 29deg +/-1 each, and 34 deg +/- 1 total. block the second set of points and set your dwell to 29, then remove the block and adjust the second set until your dwell is 34(TOTAL). i am very happy with my dual point distributor.