All Small Six Aftermarket 1100 Issues

[0Meltdown0]

Hey all! First post here.

Long story- I have a 64.5 Mustang that I recently revived after it sat 20+ years. The original autolite 1100 carburetor ran good EXCEPT for the idle mixture. When I tried to adjust the mixture on the carb the head of the screw snapped and left the rest seized solid in the carb. After being brutally attacked with easy-outs and drill bits, that carb-body is no longer salvagable.

So I got a copy-cat 1100 online that seems to have decent build quality, the only problem is now the car behaves strange under load. This includes a kinda "bumpy" feeling during acceleration and the car will sometimes stumble coming off the line or when downshifting into 2nd.

I guess my question is, could this be the jetting? The engine idles great now and seems to rev fine with the clutch in, it only seems to act up under load. Would it be possible to take the factory jets from the original carb and use them in the new one? Could the issue be completely unrelated? Does the issue even exist in the first place?
What is the meaning of life?

I'm 18 and very new to the hobby. I still have a lot to learn about carburetor tuning.

T.I.A. !!!


(accidentally posted this in the wrong category before, sorry moderators!)

 

[ActionYobbo]

Yes check the jet sizes
The symptoms you describe can be caused by the jet being too big.

 

[frozenrabbit]

trash that junk aftermarket carb, not much success for anyone with those. original units are easy to find on ebay.

 

[powerband]

welcome to a group that is more than willing to provide answers to questions you haven't asked ...
.
... they say Carburetor is French for "Don't F*^k with it"
.
first think SIMPLE - did you connect the vacuum line from carb to distibutor? . Ignition and fuel working together are all there is to 'tuning'.
.
again go over the carb/fuel supply and ignition for obvious issues before deciding on 'new' carb as source of running 'strange under load'.
.
now that your hands that smell like gas anyway, fun to open that brand-new 1100 and see what you think. The Main Jet doubtful marked for size, float and fuel inlet checked for build material contamination , only 'adjustment' is float - fuel level for best idle/run mix. My experience with the Clone Carbs is they are exact to the dimensions of originals and have only slight alterations internally. Clone Carb parts screws are extremely tight for some reason
.

large number of vendors selling 'offshore' low cost clone carbs leads to questions of quality, but since no domestic source of new carbs loke 1100's in @ 40 years WTF ... . I've seen the unmistakable shiny aluminum CLONE carbs on early Chevy pickup sixes, Volvo P1800, hot rod 350/350's and numerous Holley 4Bbl's, Rochester Qjets, etc at cruises and shows. Original carbs were Zinc based and dull grey but the clones are bright aluminum and weight 1/4 of originals.

Ford Falcon 1100 in Parts & Accessories for sale | eBay

www.ebay.com

.
have fun

 

[0Meltdown0]

Update- damn

I've tried everything to make this little carb body work, nothing. Swapped jets, adjusted the float height to a few different positions, tried reusing my car's old needle seat. Only made the carb run even worse. Kinda SOL here...

no domestic source of new carbs loke 1100's in @ 40 years WTF

Kinda feel the frustration here. One of the most popular cars in the U.S. and there are no proper 1100 style carbs??

Anyway, I guess I'll be watching ebay for original parts carburetors so I can mangle something together and start cruising again. Thanks for the help anyway!

 

[John Ha]

Welcome! Bummer that the copycat carb didn't work but you were lucky. My car wouldn't even start with the one I bought.

Rock Auto sells remanufactured carburetors (I bought one of those after the clone I bought didn't work). They're original carbs that have been remanufactured to original specs - mine was done by Autoline. They are a bit pricey if you don't have a good core but mine's been working flawlessly since installing it.

Just offering this as another potential source.

Also, just out of curiosity, did the replacement carb you bought match the distributor (both should be either the "load-o-matic" variety or not)? If not, they won't work well together, although it's possible that someone in the past changed the distributor and carb to the later non-load-o-matic versions.

 

[Frank]

Update- damn

I've tried everything to make this little carb body work, nothing. Swapped jets, adjusted the float height to a few different positions, tried reusing my car's old needle seat. Only made the carb run even worse. Kinda SOL here...


Kinda feel the frustration here. One of the most popular cars in the U.S. and there are no proper 1100 style carbs??

Anyway, I guess I'll be watching ebay for original parts carburetors so I can mangle something together and start cruising again. Thanks for the help anyway!

0Meltdown0- welcome! It's rare to get a china carb that functions correctly, either at all, or in every individual circuit. Finding a good USA carb (original equipment) is difficult. I've had a couple of dud rebuilt units, the physical body of the unit was worn out- loose throttle shafts, slack linkage, etc.
This company has a good reputation. The link is one example, shop around with different years, etc and you should find something correct. They sometimes have factory rebuilds, and they sometimes offer new. They have Rebuild and Return also, but if your original carb is damaged, it won't do. Their new carbs are cast in China, but built in their facility in Jacksonville, Fla. You're going to have to accept that it's going to cost more to get quality, the knockoff carbs built entirely overseas really are junk.

Ford, 1963-1967, 144

nationalcarburetors.com

 

[bmbm40]

This Holley for sale is the 1100 replacement Ford used:

A

For Sale Thread 'Holley 1940 Carburetor D0PF 9510 K, Rebuilt, Mustang 6 Cyl. 1964-1967 & Other Fords. Replaces Autolite 1100'

Sep 15, 2025

Motorcraft branded Holley 1940 carb 4529-1 2596. These were Ford service replacements for the Autolite 1100 (SCV) which was discontinued. They were branded either Motorcraft or Autolite. This is a SCV vacuum type D0PF K, which works with the original Load O Matic distributor. Same SCV valve as on 1100. Hot air auto choke. 1-7/16 inch bore.

Cleaned and rebuilt by with all new internal components and gaskets/seals. Also new, NOS throttle dashpot, SCV valve, and base mounting gasket. Experienced rebuilder. Specified replacement for the orig. Autolite for on many 170-200...

• Alkraut
• Replies: 0
• Forum: Buy, Sell, or Trade - Small Six

 

[Frank]

^^ Excellent choice!

 

[0Meltdown0]

I might still have either a Holley 1940 or 1904 that I took off a 144C.I. Falcon. If it's a 1940 I know it should work with some adjustment but what about a 1904? Would I need a different distributor for that? I'm not really sure how to I.D. the type of distributor.

I'm not sure if that's the route I'll take, I'll probably keep looking for a used 1100 to rebuild. I'm not currently in a position where I can let hundreds of dollars fall out of my pocket lol.

Again, thanks all!

 

[bmbm40]

Keep in mind the Autolite 1V carbs had different cfm ratings for the 144/170/200:

Classic Inlines Autolite Carb's

If you can find the appropriate 1100 to rebuild that would be a nice solution. Make sure to get one with the correct rating for what is in your Mustang and of course the load o matic/scv technology. 170 or 200? If you have a 170 and can find the Autolite 1100 for the 200 get that one.

There are several Mustang forums and one of their favorite past times is removing six cylinder motors and installing a v8. You could start checking theses sites for parts.

Or if your current lom/scv distributor can work with a Pertronix module you can possibly use a regular carb.

Classic Inlines Ford Six Load-O-Matic Distributor & Spark Control Valve

Not sure if you can upgrade to DSII in your block but it is an improvement:

Classic Inlines - Duraspark II Swap

Someone on here with an early block will know.

 

[pmuller9]

TTT

 

[awasson]

Keep in mind the Autolite 1V carbs had different cfm ratings for the 144/170/200:

Classic Inlines Autolite Carb's

If you can find the appropriate 1100 to rebuild that would be a nice solution. Make sure to get one with the correct rating for what is in your Mustang and of course the load o matic/scv technology. 170 or 200? If you have a 170 and can find the Autolite 1100 for the 200 get that one.

There are several Mustang forums and one of their favorite past times is removing six cylinder motors and installing a v8. You could start checking theses sites for parts.

Or if your current lom/scv distributor can work with a Pertronix module you can possibly use a regular carb.

Classic Inlines Ford Six Load-O-Matic Distributor & Spark Control Valve

Not sure if you can upgrade to DSII in your block but it is an improvement:

Classic Inlines - Duraspark II Swap

Someone on here with an early block will know.

I recall also seeing that the Autolite 1100 had a different model for the auto transmission vs the manual because of the vacuum detent circuit in the transmission. I haven’t verified that though.

 

[awasson]

I might still have either a Holley 1940 or 1904 that I took off a 144C.I. Falcon. If it's a 1940 I know it should work with some adjustment but what about a 1904? Would I need a different distributor for that? I'm not really sure how to I.D. the type of distributor.

I'm not sure if that's the route I'll take, I'll probably keep looking for a used 1100 to rebuild. I'm not currently in a position where I can let hundreds of dollars fall out of my pocket lol.

Again, thanks all!

Hey, welcome to the site. This place is a jackpot of knowledge.

The first thing I check with these engines when it’s a carb issue is how much fuel pressure is getting to the carb. If the fuel pump was changed recently, it’s probably providing 3 times the pressure of the original pumps and the new Clone Carbs have no tolerance for having more than a few lbs of fuel pressure. Even the original will be overwhelmed by pressure from the new fuel pumps.

If it were me, I would reassemble the clone carb right back to stock, put it back on. Temporarily, for testing purposes, disconnect the fuel pump inlet from the tank and just block it off from leaking. Then I would get something you could use to supply gas with a gravity feed to the carb to see if you can get it to behave with a known low pressure. If it works, hook up the fuel pump and run a fuel pressure regulator inline to the carb.