2bbl and 4bbl Distributors?

-
eekvonzipper

eekvonzipper

My Member is Legendary!
FABO Gold Member
Joined
Apr 18, 2020
Messages
1,485
Reaction score
1,559
Location
Cadet, Missouri
What's the difference? if you set-up a Dizzy on a machine for a 4bbl
and drop it into a 2bbl car what will happen?
I just got my rebuilt dizzy from a member here. I mentioned at least 3 times in our conversation that it was a 273 2-bbl.
It came with a full Report Card of all the Testing done. (Very Professional like)
It say's 273-4 All over the paperwork tho...
Should I drop it in?

20201110_120849.jpg


distrib3.JPG
 
eekvonzipper said:
Thanks WR!
Still, I would like to know why he needed to know which carb it had...
Click to expand...
Some cars came with more of a performance curve. Actually, any older 2bbl car will benefit when somebody curves the distributor, and pulls more initial timing. For instance, a stock 318 2bbl in the early 70's may call for TDC or 2* BTDC. I usually end up running them around 10-14* BTDC, and if need be I pull some timing out of total advancement. A lot of times going with weaker springs for the mechanical weights is a benefit as well.

Best to let Halifaxhops answer in your particular case
 
It's not the carburetor. It's all of the engine. compression ratio, weight, and camshaft. "It just happens" that most of the time, 4bbl engines also have more compression and camshaft, dual exhaust, etc, generally a "high performance" engine.

You can recurve just about any dist. except lean burn
 
Also, it is not a dizzy. The carburetor is not a carby, the manifold is not a manny BUT somehow, a transmission is an okay word to shorten to "tranny".....:D
 
Last edited:
eekvonzipper said:
What's the difference? if you set-up a Dizzy on a machine for a 4bbl
and drop it into a 2bbl car what will happen?
I just got my rebuilt dizzy from a member here. I mentioned at least 3 times in our conversation that it was a 273 2-bbl.
It came with a full Report Card of all the Testing done. (Very Professional like)
It say's 273-4 All over the paperwork tho...
Should I drop it in?

View attachment 1715627689

View attachment 1715627696
Click to expand...
As delivered from the factory, each distributor is set up for how the engine is equipped and what it runs in and so on and so forth. This is important during the emissions years and deeper into those years the more important it becomes for a proper running engine while passing the emissions test.

Now! The probable more aggressive curve in that (your) distributor will only help performance and probably mileage. (Good probability!) what an engine likes for more power and mileage, emissions testing/passing doesn’t like.

A more aggressive curve will only serve you better.
I’d drop that right in and go.
 
It could be that vacuum is measured differently from a 2 barrel to a four barrel, requiring a different vacuum advance to get the vacuum assist "just right".
 
RustyRatRod said:
It could be that vacuum is measured differently from a 2 barrel to a four barrel, requiring a different vacuum advance to get the vacuum assist "just right".
Click to expand...
Ah, the reason for the post rears it's head. This is exactly my worry.
 
Slap it in. It'll never know the difference.
 
Fabulous! :steering:
Maybe his notes meant 273-4Speed..?
I did tell him it was a 2bbl StickShift... Duh. My Bad. :realcrazy:
 
Last edited:
Oh crap Somehow missed that. Prob wake it up a bit if anything. I prob meant 273 4 speed. That was a crazy week here. Any issues just send it to me I pay the rides.
 
Last edited:
If it doesn't run right, now you have an excuse to convert your engine to a 4 bbl to match the distributor... :D
 
halifaxhops said:
Oh crap Somehow missed that. Prob wake it up a bit if anything. I prob meant 273 4 speed. That was a crazy week here. Any issues just send it to me I pay the rides.
Click to expand...
I would have to agree with that because the 4bbl was a dual point and the 2bbl was single point as he has.
 
You must log in or register to reply here.
-

Back
Top