Here's a good one. I haven't done anything but cuss and wash my hands...

'68 pickup with 318LA. Stock, points ignition. Runs great except that distributor is worn out. Mechanical advance is wonky and vacuum advance is non-existent.

I figure, heck why not upgrade to electronic? I buy an electronic distributor on ebay for a core, NAPA gets me a rebuilt electronic distributor. I get a couple orange control boxes on ebay. I install an electronic voltage regulator, ignition box, distributor...it acts a little silly at first, then a snatch the base timing to about 15* and it settles to a nice smooth idle. Great. I throttle up a little to watch the ignition timing, and IT GOES BACKWARDS! I mean with the vacuum disconnected and 15* base timing, by about 1200rpm the thing goes back to 0* timing.

WTH?

should have gottin a reman points dizzy from auto zone for 30$ IMHO

then drop a pertronix points conversion in it

could have got one for a reverse rotation marine engine

that would explane the timing plate moving the wrong way as the dizzy is spinning the wrong way

Apparently it is a marine distributor that made its way into the wrong box as a core...the vacuum pot is on the opposite side of the distributor from the original. The shaft is bent too, so I guess I'll be getting a refund at NAPA and ordering a MP from Mancini.

A reverse rotation dist , I never woulda guessed but I'm sure Michaels' saw his share of marine stuff down in the Florida swamps. Might just get a used electronic dist, they pretty much last forever as there isn't alot of bushing wear like the points ones and it'd sure be cheaper & you just need a decent one to trigger the ECU and I'd be more concerned w the orange boxs' quality. Good luck.

RB distributor. Keep it or sell it to me. I'll give you a core.

think it was a sb dizzy going the wrong way

The RB and SB distributors are the same length and I have seen in the past them mixed up. Course when the weights advance they go the wrong way and retard timing instead. Turn rotor against the weight springs if it turns counter clock wise and returns clockwise it is likely a bb diizzy.

We once got an MP conversion from mancini for a BB with a SB dizzy in it but I noticed it before we put it on.

The vacuum advance will pull advance Counter Clockwise also instead of clock wise if it is a BB dizzy!

my RB dist is taller than my sb dist

hows that fit

now the advance plates and guts maybswap but the shaft is deff longer on the RB than the SB

I have allways thought they are engine specif

and the revs rotation ones just have diff guts and advance plates

gotta remember which dist goes in which engine when working on a twin sb offshore boat with one revs rotation engine

or if its revs rotation out drives only

The A and RB or is it the B and A will fit on the engine into the distributor drive. You have two types of distributors there!~ LOL!!

the b is shorter than the rb

the la is shorter than the b and rb

in the pics it an la on the left and rb on the right

the flange that fits into the block to the end of shaft is differant length on all 3 as far as i know and remember

i know the polly and LA and "maybe" an early hemi use the same dist though

could be wrong on that early hemi part,think I have read that some where