DS-II & '67 Autolite 1100 Compatibility???

[Anonymous]

Almost ready to do the DS-II swap, and a question was raised. Is the stock '67 Autolite 1100 going to work with the DS-II, or is the vacuum advance all screwy? ONly one vacuum line to the dizzy. Is it load-a-matic, or not? Does it matter to the installation of a new dizzy?

This question is further compounded by the comments in the recent thread on vacuum/ spark advance. Confused now.

So, do I need a new carb to go with my new dizzy? I'm just trying to make my poor-running car into a good running car right now. Don' wanna make it a non-running car (again). Frankenclutch Ack! *shudders*

Stop me, before I kill again!!

--mikey

 

[CobraSix]

without getting into sticky details, I ran my DS2 on an Autolite 1100 for the better part of a year with absolutely no problems at all. I connected teh DS2 to the ported vacuum on the carb, and plugged the port on the manifold.

Slade

 

[Anonymous]

Ooh! Gory details on plugging the manifold port, por favor?

It's been awhile since I've had the carb off. What am I looking for, and what should I plug it with? I'd use my finger, but I need it to point and laugh with (at the ID10T in the mirror).

It also occurs to me- are there any external tell-tale signs of Load-a-matic? The dizzy has a single vac hookup. No clue if it's original or not. I think I saw info on that in another thread. Sorry to be so dense as to ask again. I hate electrons.


--mikey

 

[cdherman]

I have sent you a picture of a loadomatic style 1100 carb. It has a spark control valve slightly above and to the left of the vacuum hookup.

Please understand -- the ONLY vacuum hookup that the 1100 loadomatic carb has, is neither manifold, nor ported vacuum. It is a combination of ported vacuum and venturi vacuum. See the above sticky post for more info on loadomatic.

If your 1100 is from 67, there is a good chance it does not have the spark control valve anyhow. In that case, you do not have a loadomatic carb, and the vacuum port on the carb has ported vacuum.

To clarify -- ported vacuum comes from a small port in the carb neck which lies right above the accerator plate. At idle, the plate is closed, and the carb sees no vacuum, even though a large amount of manifold vacuum exists. When you begin to open the accelerator, the plate opens and the carb and port above the plate begin to see the manifold vacuum. The ported vacuum and the manifold vacuum are essentially identical at all times EXCEPT at idle when the plate is closed.

Why ported, as opposed to manifold vacuum? I have read that engines run cooler, but produce more polution when running a manifold source of vacuum to the distributor. Ported vacuum came onto the scene before all the worry about smog though so there is more to it than that. Running a manifold source of vacuum to your DSII dizzy might work, so long as you are very careful to set the timeing with the vacuum disconected and plugged. But you would only want to do that if you do have a loadomatic carb.

Not being aquainted with small six intakes, I am not certain if you have a vacuum port on the manifold. My 240 has 2, one for the PCV system, and one for accessories.