Is this a LOM dizzy or a dual action dizzy?

rmcphearson

Well-known member
Is this a Load-O-Matic dizzy requiring a SCV or is it a dual action that has mechanical and vacuum advance?

Thanks,
Roland
 
Hi, I can't see your distributor.
68 and later had the modern vacuum and mechanical advance.
Good luck
 
One of the tells is the vacuum diaphragm. I don't know if they are all like this but the ones that are hard piped or have tubing/pipe connection instead of built in smooth nipples are scv types. All the 68/69 and later dual advance types used hose. The canisters look totally different to.
 
Thanks Bubba!

That makes sense because this is a '69 block and '70 head (or vise versa-I don't have my notes in front of me). Now, I have a Autolite 1100 on it and the vacuum line to the dizzy is coming from the SCV! Don't look at me, that's how I bought it!

What source should I use? There is a large port on the side of the carb that feeds the PCV and there is the manifold plug. Should I be using one of those?
 
Hi, Someone put the wrong carb on your engine. Not too surprising. I would use direct manifold vacuum for now. Most guys use the timed, or ported vacuum for the distributor advance. Ported vacuum does not give advance at idle, only high vacuum conditions like steady cruise. Direct manifold vacuum will advance the timing at idle, which could raise the idle. So you may have to lower the idle after your switch. Good luck
 
rmcphearson":1il3ikta said:
Now, I have a Autolite 1100 on it and the vacuum line to the dizzy is coming from the SCV! Don't look at me, that's how I bought it!
What source should I use? There is a large port on the side of the carb that feeds the PCV and there is the manifold plug. Should I be using one of those?
These darn che**y guys!
Time for the "Handbook" (Oh, I think U said U have one? May B the above 'tech archive' @ the big blue box - crossed screwdriver/wrench).
 
Your SCV Carb. can be modified for ported vacuum.
There is a tech article on how to do it on the forum tech section.
I can do them for $50.00 plus parts if manifold vacuum is not producing desired results.
The best thing you could do if you want to keep the present distributor is get rid of the points & install a Pertronix 1.
A distributor recurve would also reap benefits. Bill
 
Thanks all. I don't want to put anymore time or money into this Autolite 1100. I have a Holley 1940 that I plan to get rebuilt by a pro.

1) I don't see a SCV on the Holley 1940 so I assume it has a ported vacuum source?

2) According to my bible "Clifford lists a Mallory Dual Point and a Unilite Electronic distributor, with or without vacuum advance." So, if I get one of these without vacuum advance, I guess I could keep using the Autolite 1100 for a while? Are there any cons to this type of distributor?

Thanks,
Roland
 
1) Yes

2) Don't bother, even if you can find one. Get the carb and get that dialed in first. Then if you want to upgrade the ignition, do what Bill says and swap the points out for a DSI pickup. It'll be cheap to do and look like a points setup if that's important. Or swap the distributor out for late a 70's DSII distributor. Either way, use it w/whatever module and coil you want to use. The only advantage of the later distributor is the size of the cap. Who knows whether you need it or not in particular.

The biggest driver with ignition swaps on these engines is the LoM stuff. You've got that part covered. The points will be fine until whenever. You need the right carb. And like b ron co said, I'd try using manifold vacuum in the meantime but you'll have to compensate by turning the idle down and fine tuning the mixture screw when you hook the vacuum back up after checking/setting the timing. Close off the scv timing port. Later pull the scv and plug it with an 1/8" pipe plug just for fun. Do you have a dwell gauge?
 
Howdy Roland:

FYI- Holley 1940s came both with SCVs and without. They were a generic Service Replacement part sold through Ford Service Dept. They were refitted to fit any Ford vehicle that used to have an Autolite carb through to about 1970. So check it out carefully.

Adios, David
 
Ok, great, thanks guys. I will take a photo of my Holley 1940 and someone can confirm for me it's not supposed to have a SCV.

If I swap the points out for a DSI pickup will I still need a dwell meter? I don't have one. I don't even have a timing light.

-Roland
 
You need a timing light. Either the carb will have an scv or a port for it or it won't. If you know what a holley power valve looks like, they look the same. If there is one or a spot on the carb with an 1/8" pipe plug in it, it's scv type carb.
 
1) Should I get the Pertronix ignitor part # 1261 or ignitor II part # 91261?
2) What else should I get with it?
 
Well, well, speak of the devil. Here I've been trying to figure out exactly which ignitor/coil to order. I even sent Pertronix a message asking about what coil to get and if it requires a resistor yada yada yada. (I didn't get a reply). And my bleeping points take a crap while driving home yesterday. The engine won't fire at all now. I'm assuming it's the points. I have 10v at the + terminal of the coil but no spark. I popped the dist cap and the points look they've been drug down the road then chewed on by Oprah.

I ordered a 1261 ignitor and flame thrower coil for $113 total from ebay and I will have to wait a week. Dang it.
 
thanks for the update.

For additional ideas I personnally would need an updated list of components.
Starting to loose track of what yer actually running.

I think the 1100 is way better than the 1940. Pare it w/the DSII for performance (MPGs & pep).
 
That should be a great improvement when you get the 1261 Pertronix and Flame Thrower coil. (y) :nod:
 
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