Questions on running bubba's distributor

R

Rollingmenace

Member
I want to start off by saying in no way is this thread intended to bash Jim or his product... I'm just curious about a few things and want some of your opinions.. I know Jim checks in here ocassionally maybe he can comment as well .. I plan on calling him on my day off to clarify...
I have a 51 with a 8ba in it 12v converted ... I purchased one of the bubbatronics mech advance dizzys from bubba.. Upon arrival this thing looked like a nice piece .. I'm not real savy when it comes to working on these old engines but I'm learning .. I had the help of one of the guys at work who is into old jeeps and old Chevy trucks to set up new dizzy...

We pulled the ford one out immediately I noticed a difference the ford dizzy shaft stuck past the drive gear about 3/4 to one inch .. On bubba's it is less than 1/4 inch .. I believe this is supposed to ride in a bushing to help keep unit running true...

Now when we set the bubba's dizzy it went into the timing cover as much as the old ford did.. but one thing we noticed is it seemed to have a lot less engagement on the cam gear than the old ford did.. And if we pull it up ever so slightly we loose engagement on the gear... Does this sound correct....

Next we did not check the old ford in the car but it seems the bubba's has a lot of movement at the top of dizzy.. There seems to be more slack in the rotor than the old ford left to right.. It also seems the bubba's has a fair amount of oscilAtion at the top of unit when running in the car... We pulled and mic the collars where they slide into the timing cover and is seems there close within a few thousandths ...

The main concern I have is I don't want this thing chewing up my cam gear on the car .... What are your thoughts or experiences on this thanks
 
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There were two types of 8BA distributors, ones that used the lower support bushing and ones that didn't. Is your timing cover cast iron or aluminum?

It could be the Chev shaft is not going into the lower bushing, and is preventing the distributor from seating fully? I would ask Jim!
 
I'm not 100% sure on my type of cover as it was painted I'll check it when I get home... If I had to guess though looking at the old distributor it deffinitly seated into the bushing.. I'll try and get ahold of Jim today after I leave work...
 
I think since you purchased the parts from Jim the best bet, before you mess up some parts, is to call him back for some helpful advise rather than get incorrect information off a message board.
 
Rollingmenace said:
I'm not 100% sure on my type of cover as it was painted I'll check it when I get home... If I had to guess though looking at the old distributor it deffinitly seated into the bushing.. I'll try and get ahold of Jim today after I leave work...
Click to expand...


Pictured below are the 4 types of 8BA front covers I've come across. "A" and "B" are aluminum, while "C" and "D" are cast iron.
The distributor on the left is cast iron with a full length body. The one on the right is aluminum, has a short body with an extended shaft.

DCP_3265.jpg


The rear of the covers are pictured below, and shows that the aluminum short body distributor with the extended shaft should only be used with "A" that has the lower support, (As Ford did) although it will fit cover "B". The cast iron distributor can be used with "B", "C" and "D" but would not have complete upper support with "A", IMO.

DCP_3271-1.jpg


The picture below shows the distributors in more detail. The alloy housing has less than 1" of upper support, while the "stepped" cast iron housing has 4 1/2" of support.

DCP_3294-2.jpg
 
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V8 Bob

This is excellent. I have known about the differences for years but never seen it depicted. This has been bookmarked into my tech file.
 
GOOD QUESTIONS!!

AFTER SHIPPING ALMOST 1000 OF THESE UNITS WE HAVE MADE SOME SMALL CHANGES AS WE GO.

Our first units we made two models , one for the cast iron and one for the aluminum (i Call it the merc cover). One had the shaft cut off for the cast and we left shaft hanging out for the mercs etc with the lower support.
After some times we checked out all the covers and decided that the cover with the lower support could use less shaft extension and we cut back on the length allowing one unit to be used with any and all covers.
This has worked very well thru hundreds of units. As theres NO load on the distributor other than a set of points ( no oil pump to drive ) the lower support does very little . ( if a mag is used i would suggest using the full shaft as the mag is a heavy load)

A couple installation tips ( included with each distributor) , align the distributor
in the cover making sure if a support cover is being used to allow the support to fit in the machined aluminum support. ( note this is not a bushing but a machined aluminum parts with tons of front lube splashing on it all the time.
Number two , we install a aluminum plate using the measurement off a stock distributor. I suggest using a stud in place of the hold down bolt and checking the clearance between the head and distributor , placing a washer either under ( if needed) the plate or above based on actual feel. Depending on heads used this can vary a little bit.
I personally check every distributor and gear in a Merc cover before shipping for fit and gear location, to assure machine work matches original fit and finish..

Once installed and tightened down there should be no wobble when running...
feel free to give me a call at 317-487-9460 for further help.

My most important question is " hows it run".
 
Wow Bob, you had me out of my chair and into the shop as soon as I read your post about the different front covers because I'm going with the SBC distributor too albeit from another excellent source. Turns out I have the "B" aluminum cover and all is well. I knew there were both aluminum and cast iron covers but didn't know the significance of each. Thanks for sharing. This forum is great!!
Howard
 
GreenMonster48 said:
Very interesting! What was the reason for the two different distributors? Or was it just one of those Ford things :rolleyes:?
Click to expand...

The cast iron bodies were used from ('48 truck) '49 car until sometime in '50, when the aluminum distributors started being used on U.S. Fords and Mercurys, according to their shop manuals. I don't have any info if trucks also switched to alloy. :)
 
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