In desparate need of early model 71 dart fuel cap

[Oldmanmopar]

Yes Cheryl, well the one i got fits perfect, the grip sits horizontal to the ground so the stripes when applied on my 71 demon will look correct with half stripe and half butterscotch. here are some pics and measurements, the overall width from ear to ear is .635 and from the ear to the rubber seal is aprx .170. the ears are the smaller ones hope this helps if NE1 needs more measurements let me know, the one i thought is correct in your pic Cheryl looks to have ears/tangs that are to large.

You got it thats a 71 cap. These are hard to find. They came on 71 abody cars with collision impact protection. They were stopped because of the dome light ignighting the fuel when opening the door after a rearend collision. That little pipe in your trunk is the culpret. The cap is forced off when the tank is smashed. Putting the fuel into the roof of the car to contain it. But when you opened the door you would ignite the fuel. Those four hoses coming from the tank are not vents.This was hushed up and taken out for 72 .Everything was changes so you couldn't put this in later years. 70 on back were all the same but they were not vented. so they changed th size of the ears so you couldn't replace a 71 vented cap with a 71 nonvented . I took a bunch of these caps to Carlisle. I sold them all to one person for $65 dollars each. I kept 2 for each of my cars I do have other year caps with necks. Heres the problem. Some slide in from the outside of the quarter and the quarter has a diferent indent for this. some have 4 holes instead of three. Others are cLocked wrong. a 70 cap and neck will fit use the vent tube because the cap is not vented on a 70. 72 and up will not fit they slide in from the outside. Darts are totaly different the flange is at a different angle. The darts have a flatter quarter Where dusters demons and dart sports have more of a bulge. I used a 71 neck and cap on my 71 duster but I used the vent tube fron the 70 also. This gave a larger vent for greater fuel flow . I run a #8 fuel line.

 

[LH23H2R]

The difference is EEC ( Charcoal Canister ) vs. non-EEC .

One style is vented ( non-EEC ) , the other is non-vented ( EEC ; closed system ) .

NOT all Ca. cars got the EEC setup in 1970 .
A fellow I worked with had -- and hopefully still has -- an all-original 1970 Swinger 340 , original Ca. model , untouched engine compartment ; he bought it new in Spring 1970 from the local Dodge dealership.
NO EEC setup ; and , it had a chrome fuel cap .
Also , non-thermostatic air cleaner !

Opposite end of the 1970 model spectrum :
1970 'Cuda 340 ( BS23H0E ) .
Built in the L.A. ( Commerce ) plant in late 1969 , for Ca consumption .

Had the EEC setup ; was also sans N42 exhaust tips ( Noise Reduction Pkg , required in certain counties in Ca. ) .

I believe that -- at least when it comes to "B" & "E" bodies , as well as certain "A" Bodies -- it came down to :

- N95 ( Cleaner Air Pkg / Calif Emissions Pkg )
- Motor
- Whether or not the car had an N96 ( Fresh Air Intake , et al. ) hood

I've noticed throughout the years that certain motors didn't get the EEC setup :

- 440 3X2 ( Six Pack / Six Barrel )
- Hemi
- 340 3X2 ( 1970 T/A motor )

-OR-

340 / 383 / 440 single four barrel induction if the Ram Charger ( et al. ) hood , Shaker hood , or any other F.A.I. hood ( scoops on 1970 & 1971 340 Dart / Duster / Demon ) was ordered ( standard in some cases ) .

When the cap has a double-step 'screw' setup ( takes two turns to release the cap from its rest ) , it also has EEC ; these are the non-vented caps ( closed system ).
If there's only one-twist to release the cap , it's a vented ( non-EEC ) cap .

I hope this is of some help ...

 

[BlueSwinger]

My car is '70 model year, but it is a California car so has the EEC. I have the cap as described in post #27... visually identical to the one on the left in post #5.

As described above, it takes two turns to release the cap, but that could also be described as two motions for a total turn of about 270 degrees (3/4 of a full turn) due to the two sets of latches holding the cap into the filler tube.

So... question: Since I am removing all of the EEC equipment from my car (yes, I have checked with local regulations first, keeping PCV of course), it sounds like I should replace my filler tube with the vented style with vented cap... correct? And I hope this is the more common one to find?

Also, my cap is chrome with black plastic handle. I have been assuming this was aftermarket. Or is that how the factory non-vented caps were?

 

[slantsixdan]

Factory caps were body color. Service replacement caps could be had in primer (for bodywork jobs) or in chrome with chrome handle (for "I lost my gas cap but I'm not going to pay for paintwork" situations). Aftermarket caps often had black plastic handles. See here for complete info on the fuel tank vent system on your '70 California car. Removing it is kinda pointless.

 

[BlueSwinger]

Factory caps were body color. Service replacement caps could be had in primer (for bodywork jobs) or in chrome with chrome handle (for "I lost my gas cap but I'm not going to pay for paintwork" situations). Aftermarket caps often had black plastic handles. See here for complete info on the fuel tank vent system on your '70 California car. Removing it is kinda pointless.

Thanks for the info. However, I'm replacing the tank, fuel lines... everything... basically every last thing in the drivetrain, mechanical, fuel systems in the entire car is being replaced, and none of my EEC (or ECS or whatever it's called) is in good condition, so in that light, I don't think it's pointless. If I were doing it solely to remove it, then sure.

So, it sounds like I should replace my filler tube with the vented style with vented cap to finish off the job.