Fuel Line Size

I have a 69 Coronet R/T . Is the stock fuel line size 3/8"? And also is the stock fuel pump size 5/16"? The car didn't have fuel lines when I bought it so I had no personal reference. Thanks.

3/8 would be preferred with a BB assuming it's basically stock or mild mod's

I believe that is correct. 3/8" from tank to pump. 5/16" from pump to carb.

The 440 and Hemi got the 3/8 from tank to the pump 5/16 from the pump to carb. The 383 down used 5/16 the entire way

Im of the idea all 440 and hemi cars were SUPPOSED to get 3/8" line.

But I remember many 440 cars from 25-30 years Ive had in the day that were 5/16" . Both 4 bbl and sixpack cars

This^^, Yep, my A12 had a 5/16" and so did any 440 I worked on, "in the day"

Joe

Gtx6970 and jlatessa, I remember from the ones I've had in the past (440 cars) that they had 5/16" lines from the fuel tank. I'm in the process of connecting my new lines up on my current 440, and I don't ever remember going from a 3,8" line to the 5/16" inlet on the fuel pump. I don't believe any rubber hose is 3/8" on one end and 5/16" on the other. I looked up the fuel pump in my SM and it lists MS4845 for the number of the fuel pump. That particular pump has a 5/16" inlet.

I can make my situation work, but I have never had to go from larger line to smaller line before. Maybe I should have gotten the 5/16" line in the first place.

When I replaced the fuel line in my '68 Charger (440) 20 years ago, the old line was definitely 3/8". I remember because tech support at wherever I was ordering the new line from insisted the correct size was 5/16", and that the line in my car must have been changed. Sure looked like factory to me. I installed a 3/8" line to match the old one.

it should also have a 1/4 return line

My first 1969 gtx vert

Had a 5/16 main line. 1/4 return.
But had a 3/8 sender. Best I could tell was all factory

Had a 5/16 rubber hose forced over the 3/8 sender

Don't remember fuel pump fitting size

My 2nd gtx vert was all 3/8 front to back.

5/16” on everything but the Hemi from all I’ve seen in 60 years

Huh: I also thought I'd seen somewhere in factory literature that 440s got 3/8".
Haven't had a 440 in many years, so I can't say what mine had; but I had a 512" RB that ran fine with a 3/8" system and only a good mech pump.

My 70 rt charger has 3/8 oem.

It is funny as the parts book seems useless as it just mentions generic roll of 5/16" fuel line even under hemi. Didn't see anything in the tech bulletins. In the 69 dealer book under engine selection the hemi is listed as having "special 3/8" fuel line. I thought at some point in 68/69 time frame 440/hemi got the 3/8" fuel line to the pump. But who knows. Begs the question what did the A-12 get, since they started as 383s.

I bought a 69 A12 that was that was in the restoration process, they hadn't gotten to the point of doing the fuel line, what was painted over on the underside of the car was 5/16 with no return line. The first run , 3/29 build date , had 5/16 lines, I don't know where the discussion has gone as I haven't been active in those forums for years .

Well, I purchased an A12 new in the spring of 1969 and in upgrading to a electric fuel pump from the back frame rail,
I can unequivocally tell you that I replaced the 5/16" line going to the mechanical pump.

I'm 81 years old and have pictures of my car on the carrier next to my buddies (a salesman at the dealership) M code Barracuda.
Those were the days!!!

Joe

Just went up and calipered it...3/8 bone stock. tank to pump.

I agree, a buddies Dad had a '70 Hemi 'Cuda, 4 speed, all stock, was selling it in 1975, I couldn't come up with the $2,000 for it, it wound up in Alaska. I've never seen factory 3/8" fuel lines on a mopar. IIRC, Dave Dudek extrude honed his factory 5/16" fuel lines to get a bit more flow?

B1MAXX...calipered the I.D.?

Joe

My 66 Hemi Belvedere II has 3/8” line (30,000 original miles) 69 Cuda M code 5/16”

OD. thats the hose size id.

I replaced my old lines when I restored the car but I still have the 3/8 line and sending unit. I don't know why but I kept all the old parts I could.

B1MAXX, you are correct, learned something today.
So we're better off with a 3/8" flex fuel hose with a larger I.D.??

Joe

I have 4 or 5 old original pumps, I know one is off a 68 GTX, all are 5/16” non Carter pumps.

possibly, but in my experience the pumps were the limiting factor from the factory with 3/8 steel line, except maybe the hemi pump...I never had one of those. My stock 440 pump would cut in and out under full throttle bonzai blasts.

After finding my original fuel line from my car, I found that it is 5/16. I also measured the original fuel line on my 70 hemi charger and it is 5/16 also. I personally think that both sizes were used depending possibly on what was available at the time.

The outside diameter of the stock fuel lines are not what the insides are, a 5/16 O.D. may be less than .300 I.D., less around corners
I try and use a 1/2 O.D. thin wall steel tube for my half way serious race cars, a lot larger than needed is way better than a tiny bit to small
If I can't fatten the mixture up enough to slow the MPG down in the 1/4 mile I don't have enough fuel delivery
My new heads up no prep car will have #12 AN from the fuel tank to the crank driven mechanical race pump on the front of the gear drive for the centrifugal superchargers and other accessory needed to be completive

I don't buy this one bit. Maybe the 69.but not the 70.
I should clarify.... in regard to the tank to pump.