Best carb/distributor combo for a stock 300?

Oregoon

Well-known member
My '66 F100 has a 300, fed and ignited by an Autolite 1100 and a Load-o-matic. The carb is shot the point where it'd be as costly to rebuild it as it would to replace it--as in a lot of machining is required.

Also, I'm learning that the Load-o-matic isn't very effective, and since the two go together like dirty socks and smelly boots, it's time to find a better aternative, being as I'm going to spend some money anyway.

So: What's the best combo for my stock motor? My truck's a two wheel drive, has a 3-on-the-tree and a 3.50 rear-end, and will be driven daily. It may haul an occasional load of barkdust or yard debris. Nothing exciting...

I'm looking for reasonable economy and a relative ease of maintenance.

Any suggestions?

As always, I am grateful for anyone who takes their time to lend me some guidance, and look forward to being able to do the same.
 

jack orchard

Well-known member
Great choice of a truck. I think you will get many different opinions. Mine is only one. I prefer an Autolite 2100 2 barrel carb w/1.08 venturi (with manual choke if you can find one). This can be installed with an adapter to the stock intake manifold, or on an aftermarket intake manifold. If you go to the trouble and the expense to change the intake manifold, you might consider adding EFI exhaust manifolds. I prefer Duraspark II ignition. This is just my opinion. I am sure others will have different ideas. Good luck,....jack
 
The cheapest way to good MPG and power I'd think would to get yourself a stock duraspark(1975-76) or duraspark II (1977-1980) distributor and a Carter YF carb.
You might be able to find all the parts you need used on one truck. Just look for the Vacuum advance can on the distributor of any 1975 up to about 1982 or so.
If a truck in the 1980 and up has a flat grey plugs where all the wire go into the distributor its NOT (Ignition or carb) what you want.

on the ignition side you would also want to get the harness between the distributor, Coil and the ignition module box.

There is a way where you could just get he carb and distributor and build a HEI igniton system with a GM module and you can findinfo on it at http://www.gofastforless.com
 
:oops: I have a correction some where around the years they started putting EGR valves on our sixes the bolt pattern on the carb bas got bigger on these 300s so if you find one of the latter models you might need the intake manifold as well.
 

blmhawkeye

Well-known member
Look into advancing the cam too, it really helps. Also if it doesnt already have it need steel crank/cam gears or itll leave ya walking like it did me
 

Oregoon

Well-known member
blmhawkeye":2pr2x7wj said:
Look into advancing the cam too, it really helps. Also if it doesnt already have it need steel crank/cam gears or itll leave ya walking like it did me

I was under the impression the early 300s were already advanced?
 

herosandwich

Well-known member
bronoco for clarification. do you mean the boxy float bowled carter YF without an automatic choke? or the newer YFA WITH an auto choke and a more rounded float bowl?
 

J.R.

Well-known member
Oregoon":290yah3p said:
blmhawkeye":290yah3p said:
Look into advancing the cam too, it really helps. Also if it doesnt already have it need steel crank/cam gears or itll leave ya walking like it did me

I was under the impression the early 300s were already advanced?

Yeah... 1966 should be OK on cam setting. Seems like it wasn't until 1972 or so that the factory started retarding the cams about 4 degrees as part of the attempts to cleanup exhaust emissions.


J.R.
SoCal
 

herosandwich

Well-known member
also, is there a way to check if you're cam's been retarded for emissions? I've got a f100 six from 1970 that i'd like to check, seems to be straddling the line.
 
herosandwich":7kkgv60m said:
bronoco for clarification. do you mean the boxy float bowled carter YF without an automatic choke? or the newer YFA WITH an auto choke and a more rounded float bowl?

I've never noticed the difference between the the 2 unless the YFA is the Feedback carb. ?

I have a rebuilt Cater YF that was on my 80 bronco before i swapped the head and all the other stuff.
believe it or not it is so new it has the place on it to mount the mixture control solenoid. The company that did the rebuild epoxed up the hole. It worked fine on the old Bronco.
 

herosandwich

Well-known member
the YFA Has a big automatic choke on the side, and is normally marked with YF, the YF has a manual choke. that's the biggest difference.
 
herosandwich":13sw6jmo said:
the YFA Has a big automatic choke on the side, and is normally marked with YF, the YF has a manual choke. that's the biggest difference.
AS far as i know the last manual chokes had to be about 71 or 72?
 

Oregoon

Well-known member
Any good sources for Carter YFs (manual choke) or the 2bbl and adapter? Rock only seems to have R&R service on the Carter and I lack a core.

Also: Many thanks to those who've helped thus far!

Between this site and the guys over at slick60's, I'm getting the old girl together. Currently dealing with a horrendous upper respiratory viral-infection, so I have nothing but time to assess my options and formulate a plan. And drink herb tea.

Got new intake and exhaust manifold gaskets in the mail today, and will wait to get a distributor until I find a proper carb. Really got my heart set on a Carter with a manual choke, but if I have to, I'll set up a hot-air tube and go electric. How hard are the elctric YFs to convert?

I'm pretty old-school with my tastes though, so far prefer a manual set-up.
 

bubba22349

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Oregoon":2a3aegi1 said:
Any good sources for Carter YFs (manual choke) or the 2bbl and adapter? Rock only seems to have R&R service on the Carter and I lack a core.

Also: Many thanks to those who've helped thus far!

Between this site and the guys over at slick60's, I'm getting the old girl together. Currently dealing with a horrendous upper respiratory viral-infection, so I have nothing but time to assess my options and formulate a plan. And drink herb tea.

Got new intake and exhaust manifold gaskets in the mail today, and will wait to get a distributor until I find a proper carb. Really got my heart set on a Carter with a manual choke, but if I have to, I'll set up a hot-air tube and go electric. How hard are the elctric YFs to convert?

I'm pretty old-school with my tastes though, so far prefer a manual set-up.

For a 1V to 2V adapter CI has a new one for the 240 / 300 see link below, good luck on your pickup. :nod:
http://classicinlines.com/proddetail.as ... D300%2DHCA
 

motzingg

Famous Member
Take this all with a grain of salt, because I haven't run the 2v carb with the adapter on the stock manifold, but from the results here:
http://classicinlines.com/Dyno2VSwap.asp

I'd say the expense and risk of worse fuel economy/odd running aren't worth the potential 5-10% gain in horsepower. Especially if you're just looking to replace your stock and not going for max performance.

It sounds like you're going to stick with the YF, which sounds like a good idea. I did the 2100 autolite conversion by milling out my stock manifold into a big oval, bolting on a machined adapter plate, and a riser made out of aluminum for a smooth conversion from 2 small barrels into one big oval. It works great, but it was a ton of work. Even if the carb is the choke point and you can flow more with a 2-1 adapter, you're going to have air making an abrupt kink right behind the atomizer rings and I just don't see that being as good for fuel distribution. Plus you have to screw around with throttle cables/linkages and all that stuff which turns a simple bolt on job into a frustrating mess.

As far as the distributor/DS2 conversion, unless you have a good source that is known running/crashed, i'd go with all new(reman) components. I purchased everything for a '1978 F-100/ 300-6' for my conversion and it went without a hitch. It was way easier than i thought it would be. For me, the junkyard was going to come out to 60 some bucks for all the components and from Rock Auto it worked out to just under $100 including all the spark plug wires and everything. For the peace of mind knowing that i'm not running 40 year old components that might fail on me in the rain or something dumb, the extra cost is totally worth it.

I'm very very happy with the DS/DS2 system. It starts up great, runs great, very healthy feeling. Its just nice peace of mind knowing that it always works with no maintenance. I am pretty comfortable with points and have a lot of old motorcycles that are plenty reliable with them, but for the cost, DS is a no brainer. Any of that HEI or aftermarket stuff just doesn't seem as reliable to me, plus just how much spark to you really need for a 50 year old engine with 8:1 compression? I was planning on going to a hotter coil (probably 'summit' generic high performance) when/if mine failed but it hasn't gone out on me yet, so it is still stock.
 
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