2 barrel jetting

[Thedodgeguy69]

Hello all! So I've been a member for a while but have not posted anything. So here's to my first post here. The car. My fiance and I just purchased a 1963 Plymouth Fury convertable from the spring fling in LA. We just picked it up from San Diego this weekend. I went to start it to get it off the trailer and it would barley run and reaked of gas. It dawned on me that Reno NV is about 4950' higher in elevation and I need to rejet the carb for my higher altitude. The engine is a stock 361 2bbl. Anyone at about the same elevation that can recommend what jet size I should use?

 

[Jesse6869]

Like to see responses on your post as i to just removed of my cars from California to navada.

 

[RJRENTON]

Hello all! So I've been a member for a while but have not posted anything. So here's to my first post here. The car. My fiance and I just purchased a 1963 Plymouth Fury convertable from the spring fling in LA. We just picked it up from San Diego this weekend. I went to start it to get it off the trailer and it would barley run and reaked of gas. It dawned on me that Reno NV is about 4950' higher in elevation and I need to rejet the carb for my higher altitude. The engine is a stock 361 2bbl. Anyone at about the same elevation that can recommend what jet size I should use?

First of all....the carb is likely to be a 1-1/2 BBD Carter or maybe an equilivant Holley. USUALLY....when going to a higher altitude, the main metering jets (in the case of a Carter carb the metering rods are increased as well to flow less fuel) are REDUCED one POSSIBLY two jet sizes. Because at higher altitudes, the air is thinner (less dense or lower oxygen) which require a leaner mixture. Carter 1-1/ 2 BBD 2 bbl metering rods and jets are very hard to find. Holley carbs use the same style metering jets (no seperate metering rods) and they have a number stamped on them (like 55, 60, 70, etc) which indicates the orifice size.....and fuel flow capabilities...the smaller (or larger) the number, the less or more fuel flow. Suggest you obtain a copy of the factory service manual for your year, make and model, engine as all is explained with drawings and setting information....it lists the suggested metering jet reduction to try. IF you cannot find the metering jets/rods for your Carter 2 bbl, you may want to consider replacing the 2 bbl manifold and carb with a 4 bbl manifold and carb from the same year 383 engine that uses a a Carter AFB, which use parts that are significantly easier to obtain....you'll need to get a 4 bbl air filter and do a little linkage modifications......others may hsve other suggestions.....just my opinion of course....
BOB RENTON

 

[Cop car wagon]

Or find a spare pair of jets and start drilling. Harbor freight has a letter, number, fractional drill bit kit for cheap.
Drill it incrementally till the idle mixture screws are 2 turns out. You are probably over 4 to get an idle right now.
Altitude, and fuel volatility mess with all carburetors.
I had to drill and drill to get a thermo quad to work on my 80's truck.

 

[RJRENTON]

Or find a spare pair of jets and start drilling. Harbor freight has a letter, number, fractional drill bit kit for cheap.
Drill it incrementally till the idle mixture screws are 2 turns out. You are probably over 4 to get an idle right now.
Altitude, and fuel volatility mess with all carburetors.
I had to drill and drill to get a thermo quad to work on my 80's truck.

The jets on the Carter 1-1/2 BBD have a guide hole for the metering rod above the fuel metering orifice. REMEMBER it's not the diameter of the jet but a combination of the metering rod's step dimension and the jets diameter....converted to AREA, in sauare inches, THEN SUBTRACTED TO GET THE EQUIVALENT DIAMETER of the fuel metering orifice. Area varies as the square diameter...everything must be converted to area to be accurate. MOST Carter carbs use a idle feed restriction as part of the primary booster venturii assembly...this is where the idle fuel is controlled not the jets and metering rod's as the rods are already down to.minimum orifice size and do.not control idle fuel.flow.....just thought you might like to know....
BOB RENTON

 

[Thedodgeguy69]

Thanks for the info. The carb is definitely not the original one. It's a Holley 2bbl from a 71-72 400. I removed it from the car and pulled the jets. The numbers on the jets are 63. I picked up a set of 61 from summit today. I will try them out and see how it runs.

 

[RJRENTON]

Thanks for the info. The carb is definitely not the original one. It's a Holley 2bbl from a 71-72 400. I removed it from the car and pulled the jets. The numbers on the jets are 63. I picked up a set of 61 from summit today. I will try them out and see how it runs.

If the Holley carb is as you note, i believe it's a Model 2210, approximately 460 CFM rating. Some of the the emission control Holley carbs use a backward" idle mixture control feature, where the apparent idle mixture adjustment screw is an AIR BLEED and the idle fuel metering is fixed, internal to the carb. The Holley number on jet is a reference number, not necessarily the orifice size, but it can be the actual hole dimension. Your choice is a good first try....hopefully it will fix your issues. After driving the change for ~ 1000 miles +/-, pull a couple of spark plugs to see how/if the engine operation has changed. The leaner fuel mix should be evident as a cleaner center electrode and lower insulator. Make sure the carb's base gasket is not leaking and all mounting bolts are evenly tight.
BOB RENTON