by desurfer64 Mon Mar 16, 2015 9:53 amwanting to switch out my 1 barrel to a 2 barrel any unexpected problems I should look for
3 posters
1 barrel 2 barrel coversion
desurfer64- Number of posts : 11
Location : Delaware
Registration date : 2014-11-19
Seth G- Vintage-Vans Listings Manager
- Number of posts : 2087
Location : Anacortes, WA
Age : 51
Registration date : 2013-04-24
What head do you have? Look at the intake log rear of the carb, you will see a # like C7DE
What size engine?
It get's complicated. You see, before like '67 or 68, ford used what they called the Load-o-Matic carb and distributor combo. Which is a real POS. So, in order for you to switch to a non l-o-m carb, you have to change out the ignition sytem, i.e. the distributor. L-o-m's have no mechanical advance and the vacuum advance was different and will not work well with a "normal" carb.
So, if you have a 170, the very first thing you should do is pull the distributor and see if the oil pump hex dive is 1/4" or 5/16"(be sure and mark the rotor's position in relation to the body first). If it is 1/4", you are pretty much screwed. There may be a way to convert a dist using you're gear and shaft, but that is beyond what I know. Ask at fordsix.com. The only thing you can do at that point that will be easy is to get the largest carb for a load-o-matic 200 six. Which will be an Autolite 1100 with 1.2" venturi, and they're hard to find in good condition. They also made one with 1.1" venturi which is likely bigger than your's which is also hard to find descent.
If you do have a 5/16" distributor, are you planning on doing a direct mount or using an adapter? Classic Inlines has the only adapter that is worth a damn and even then you're only going to gain around 5 hp or so, direct mount with some porting and headers will net you 20-30 hp @ the wheels. Linkage is always the big issue. Depending on engine and head you may be better off going with a larger 1 barrel, like a Carter RBS. They came on 250's from 70-74 or so. Linkage is not a big deal with them, just have to find a way to remount the U shaped linkage arm that mounts to the coolant warmed carb base or reuse that base. If you have a small log head, pre '69, you'll need an adapter. In which case you can probably mount the above mentioned linkage to it. But having said all that, if you have a small log head, you're biggest improvement will come from finding a later head and exhaust manifold, calculating the combustion chamber volume and shaving it the needed amount to bring the c/r up to 8.7 or more with whatever gasket you use, likely felpro - .050" compressed. And put an RBS on it. If you can find an early 70's maverick or mustang with a 250, you can get everything you need.
What size engine?
It get's complicated. You see, before like '67 or 68, ford used what they called the Load-o-Matic carb and distributor combo. Which is a real POS. So, in order for you to switch to a non l-o-m carb, you have to change out the ignition sytem, i.e. the distributor. L-o-m's have no mechanical advance and the vacuum advance was different and will not work well with a "normal" carb.
So, if you have a 170, the very first thing you should do is pull the distributor and see if the oil pump hex dive is 1/4" or 5/16"(be sure and mark the rotor's position in relation to the body first). If it is 1/4", you are pretty much screwed. There may be a way to convert a dist using you're gear and shaft, but that is beyond what I know. Ask at fordsix.com. The only thing you can do at that point that will be easy is to get the largest carb for a load-o-matic 200 six. Which will be an Autolite 1100 with 1.2" venturi, and they're hard to find in good condition. They also made one with 1.1" venturi which is likely bigger than your's which is also hard to find descent.
If you do have a 5/16" distributor, are you planning on doing a direct mount or using an adapter? Classic Inlines has the only adapter that is worth a damn and even then you're only going to gain around 5 hp or so, direct mount with some porting and headers will net you 20-30 hp @ the wheels. Linkage is always the big issue. Depending on engine and head you may be better off going with a larger 1 barrel, like a Carter RBS. They came on 250's from 70-74 or so. Linkage is not a big deal with them, just have to find a way to remount the U shaped linkage arm that mounts to the coolant warmed carb base or reuse that base. If you have a small log head, pre '69, you'll need an adapter. In which case you can probably mount the above mentioned linkage to it. But having said all that, if you have a small log head, you're biggest improvement will come from finding a later head and exhaust manifold, calculating the combustion chamber volume and shaving it the needed amount to bring the c/r up to 8.7 or more with whatever gasket you use, likely felpro - .050" compressed. And put an RBS on it. If you can find an early 70's maverick or mustang with a 250, you can get everything you need.
jdlaugh- Number of posts : 298
Location : Tulsa, OK
Registration date : 2013-03-18
Classic Inlines has a lot of information on the smaller Ford six, including this article on converting to two barrel carb: Another issue for Econoline folks is actually fitting the larger carb in the dog house.
I have a 240 engine and have already converted to a Duraspark ignition system and have also been considering switching to a 2v carb. Right now I'm using a Carter YFA from a Ford 300, which would be a big step up if you have one of the smaller Ford sixes.
I have a 240 engine and have already converted to a Duraspark ignition system and have also been considering switching to a 2v carb. Right now I'm using a Carter YFA from a Ford 300, which would be a big step up if you have one of the smaller Ford sixes.
