I am looking for some pictures / tips on what exactly needs to be done to mount a 4bbl on the 300. I have a 390 CFM carb from holley but I need to figure out what vacuum lines I now need to run. Additionally I need to figure out who to buy the extended accelerator cable from. Any photos or articles would be helpful. I have a 82 that I am trying to change from the 1bbl to the 4 bbl. Thanks.

joseph

 

Hi Joseph - You will need a 4-barrel intake; Offenhouser makes an open and a dual-plane version. I believe Clifford makes one as well. These can be found from Summit, etc, but if can find a used one it will save a lot of money. The vacuum lines will transfer over. Your new carb and intake will have provisions for vacuum connections. Your distributor vacuum advance will go to ported vacuum on the new carburetor. If you have an automatic transmission, you will transfer over the modulator line as well. If you have power brakes, you'll transfer that over too. Lastly, any heater controls, etc will need to be transfered also. The throttle linkage will take some creativity on your part. It depends how the carburetor sits. On a dual-plane manifold, the carburetor has to sit 90 degrees which changes things around. On an open manifold, you can keep the carburetor facing forward. If you keep seat the carburetor 90 degrees as in a dual plane setup, and you have AC, the AC box will affect how you set up your linkage as it will be close proximity.

I am running an Edelbrock 500 with an Offenhauser dual-plane intake in an AC truck, so I had to custom engineer my throttle bracket. I used a cut-to-length Lokar cable. Lokar makes quality cables, however they are a tad pricey. Cheaper cables can be found from Autozone, etc. Here are some shots of my setup with close-ups of how I did my throttle linkage. My truck is a 79.

 

I'm running the Offy C-series and Edelbrock 500, here's a shot.



And I used a Lokar throttle cable mounting bracket that attaches to one of the carb studs. It works with the stock cable. Very easy and handy. There's a place you can screw in a vacuum tree on the manifold.

 

I don't have any pics from my old truck that really show the throttle cable setup-

I basically used a throttle cable from an 86 F-series with a 300, and the original throttle cable mount from the windsor that was in my 84 F250 c clamped to the intake- It never came loose, I actually had to cut the stupid clamp off when I scrapped the truck.

 

I have some in my gallery when I rebuilt my 300.

1982 Ford F100 4x2 - 300 rebuild pictures

You can reuse the original stock throttle cable and bracket it you want to make one like mine. I have a manual trans, so it might be different with an auto.

 

Check out the pictures in my gallery of my 82 F250 4x4 conversion.


Rod

 

On my 80 bronc I bought a throttle cable for a 85 F150 with a 302. It fits perfect.

 

http://i144.photobucket.com/albums/r...Picture032.jpg

http://i144.photobucket.com/albums/r194/Harte3/001.jpg

http://i144.photobucket.com/albums/r194/Harte3/003.jpg

48" Lokar Cable and a Spectre Bracket.

Mounting the carb North/South might cause a fuel distribution problem. Mounting East/West with the Primaries next to the engine like on an Offy DP or with the Secondaries next to the engine would most likely be the better bet with a Clifford or Offy C.

Also, tuning will be necessary. The usual problem is stumble off idle and/or bog when going WOT. Usually cured with a larger pump squirter, a more aggressive pump cam and/or a stiffer vacuum secondary spring. A 4-hole spacer under the carb may help with low-mid range driveability if that is a problem.

fmc400 and BVA have very nice, clean installs of the Edelbrock. Same for 1982fordf100 and the Holley.

 

what is the size of carb to go with without being overkill? id asume about 500- what cfm is the stock 1bll anyone know?

 

Stock 1 barrel is 120 or so I believe. 500 is about as high as I would go on a 300 and even that is pushing it. My intake came with a chart; there is also a calculator on Holley's website, I think.

 

500 is more than sufficient. The Edelbrock 500 seems to work quite well. A Holley 500 4v is rare. A 650 spread bore Holley might work as well as a Qjet. Both have small primaries which results in good driveability and economy. Secondaries have to be adjusted/limited so as to not "plug the toilet" when having a "teenager" moment.

 

I thought the stock 1bbl is about 220cfm, but I could be wrong.

 

Seems like I saw a figure of 195 cfm a while back so about 200 cfm MOL is close and the primaries on a small 4v don't flow too much more than that. With a 600 cfm one can probably generate more hp and tq on a well modified engine but on a stock or mild build it most likely will just result in less mpg...although one poster last winter, IIRC, said he uses a 750 dp on his plow truck.

 

Offenhauser DP intake manifold, EFI Split exhaust manifolds, Holley 390 cfm carb, true dual exhaust into flowmaster 40's and straight out the back with chrome tips.

 

I'd really like to hear your set up, with the flowmaster 40's. Did you use an X or a H pipe?