Buick 225 carb choices - offenhauser intake

Im using a buick 225 in my Flat Fender project, using a 1968 CJ5 frame with factory 225 frame mounts. This motor already has an Offenhauser intake on it. This is a 4 barrel intake with a 2 barrel adapter plate and what I think is an Motorcraft 2100 carb (please confirm).

My problem is with a 1" thick body mount, I only have 2.25" between the carb air filter mounting surface and the center hood rib. I do not want to cut the sheet metal. It seems like there is opportunity to remove the 2 barrel adapter (about 3/4" thick) and just use a 4 barrel carb to attempt to gain some room with the hood for the air cleaner (TBD, maybe a carb hat and remote air filter).

Any thoughts on what 4 barrel would fit this offenhauser intake and do well offroad? or is there a different 2 barrel carb that has a lower profile to gain some hood room.

I dont want to use more than 1" thick body mounts, and would prefer to even drop it down to 1/2" if that can be made possible.

Thoughts, Ideas, Feelings?

 

Yes, it's an Autolite/Motorcraft 2100. A fairly old one, since it has the little vent hole on top of the bowl (missing an arm that closes it when the throttle is closed) and it has what appears to be a factory manual choke.

 

I have a 470 truck avenger on a weiand intake. I have 43 jets in front and 53 in back. I think it is a 9.5 power valve from my memory and a #28 squirter. It works well now, but was a bit of a pita to get tuned to get really good driveability. The offroad capability has been fantastic from day one. I would honestly rather a rebuilt rochester and factory intake if I were doing it over again.

 

I like my MC2100 on offy intake allot. You may look for a drop base air cleaner with a flat top. It also looks like you may be able to have the adapter milled down quite a bit, or find a different adapter.

 

Interesting I have the same build flatty body on ecj5 frame with factory v6 engine mounts and hockey puck body lift for a fat 1/2 lift over stock. Offy intake with carter afb (400 cfm) and I have about 2 1/2 to the bottom of the hood rib. Likely going to a quadrajet as the afb is a spotty off road carb even with work. As mentioned others like the holley truck or 390 carb tweaked and seem happy. The qjet is good offroad as well. I'm probably going to use an air horn and divorced air filter

 

i run a holley 8007 , 390 cfm carb on the offenhauser intake. Works great for what i do.

 

Thanks for the input guys. I have been searching around for a drop air filter, or a carb hat with remote air filter. In my quick searches, I have not found a carb hat that is less than 3" tall, and have not had any luck finding a 9" diameter drop air cleaner. That is the largest diameter (centered air cleaner) I can fit with the firewall space. An offset drop air cleaner with a larger diameter may work, but not sure if it will fit around the bowl area of the 2100? Id rather not special order something for $60 just to try it. I want to know it will fit, trying to figure out how I can confirm the fit before spending money.

 

does anyone know if the offy intake is taller than a stock buick 225 intake? I wouldnt have a problem putting stock intake back on if it will help my hood clearance problem. I have one, but it is in PA, so I would have to have it shipped to Utah to be able to measure / test fit

 

ok, I just measured the offenhauser 360 4 BBL intake on my engine in the basement. Measured with a straightedge across the mating surface for the carb to the back of the top of the ribbing of the block where the rubber seal sits is about 4.75 inches. The dead engine I have mocked up in my rolling chassis with the stock 2 Bbl intake is the same measurement plus or minus an eighth.

 

Awesome! Thanks! Great info! I'll keep the offy in action in that case

 

4Vs on the 225 has been discussed a lot in the 'Early CJ-5' forum. You might get more feedback posting there than in the builds forum.

The usual objection to the 8007 is that it has the same off-pavement problems as the rest of the 4150/4160 style Holleys. They tend to suffer from bounce-induced flooding, and often will not run at specific sidehill/uphill/downhill angles. There's lots of discussion online about this - https://www.google.com/search?q=modifying+Holley+carburetor+for+off+roading&ie=utf-8&oe=utf-8 and in a search here.

Some members run the 470 CFM Truck Avenger on the 225 with good results. https://www.holley.com/products/fue.../avenger/off-road_truck_avenger/parts/0-90470 Post up in the Early CJ-5 forum and you will likely get some helpful discussion. The annular boosters are supposed to help with smaller displacement engines, but not available on the 470 - I wonder why.

 

Thanks for the input! Ill copy and paste in the early CJ5 forum. I was debating on where to post this at first.

 

This is what I used , FRAM PRA 3566, it about 1 1/2 inches thick. I found a bottom of a air cleaner that fit the carb. I cut everything off the sides, just kept the bottom. Cut it to fit outside of air filter. I then made a top out of another flat aluminum air cleaner.

 

A guy at work hooked me up with this 1975 Bronco factory air cleaner. The hood rib just barely touches and I don't have to swap out the adapter or carb. Works for me!

 

If you have a slight amount milled off the adapter you wont have anything rubbing and possibly eliminate an annoying squeak.

 

Score! That's why I like this place...