1970 Fuel Line Question L46

[Stuart K.]

I have a 1970 L46 350/350 that I am restoring. Very early February build, non-California build. The body is off the car and I'm beginning to assemble the chassis. I have a new fuel tank and have fuel line questions. How many fuel lines are there supposed to be? There are two existing steel lines (which I will replace with stainless) running from the tank along the passenger (right) side of the frame rail to the engine area (where the fuel pump will be). One is the supply line, the other is the return both running along the passenger side. I've seen diagrams depicting another return line traveling along the drivers (left side of the car) and also a charcoal canister. Are those supposed to be on the car? I'm looking for an understanding of what lines and components will be needed to correctly restore the car. I have read the NCRS manuals and all of the AIM materials, but I can't seem to get consensus. It looks like there are only the two lines that I have mentioned.

[Mark E.]

Re: 1970 Fuel Line Question L46

Stuart,

1970 cars without NA9 (evaporator control system) only had the two fuel lines along the right frame rail (supply and return).

NA9 added a fuel vapor line from the canister to the fuel tank that ran along the left frame rail.

[Leif A.]

Re: 1970 Fuel Line Question L46

Stuart,
I can't answer your fuel line questions. But, I can offer a bit of advice...avoid stainless steel fuel lines (and, brake lines), they tend to be very difficult to attain a good, leak free seal. The standard steel fuel line will outlast you and will not give you the same leak headaches. JMHO

[Stuart K.]

[Terry M.]

Re: 1970 Fuel Line Question L46

I have seen more than a few 1970 Corvettes with NA9 that were delivered to locations other than California. My guess, and it just that A GUESS, is that the factory had NA9 equipment and not enough cars scheduled for delivery to California, and they "forced" NA9 onto cars delivered anywhere.

And yes, I know 1971 Corvettes came with the vapor recovery system that was essentially what in 1970 production was called NA9.

Bottom line is you have to carefully examine the car for clips along the driver's side frame rail or other evidence of NA9 installation.

[Mark E.]

Re: 1970 Fuel Line Question L46

I have seen more than a few 1970 Corvettes with NA9 that were delivered to locations other than California. My guess, and it just that A GUESS, is that the factory had NA9 equipment and not enough cars scheduled for delivery to California, and they "forced" NA9 onto cars delivered anywhere.

Couldn't any buyer order NA9, whether in California or not? And I vaguely recall that some jurisdictions (maybe NY or NYC) required CA emissions. I don't know if this was during 1970 though.

[Patrick B.]

Re: 1970 Fuel Line Question L46

Stuart,
I can't answer your fuel line questions. But, I can offer a bit of advice...avoid stainless steel fuel lines (and, brake lines), they tend to be very difficult to attain a good, leak free seal. The standard steel fuel line will outlast you and will not give you the same leak headaches. JMHO

That would be true for brake lines and fuel lines from the fuel pump to the carb because of the flare fittings, but the fuel lines from the tank thru the frame should be trouble-free in stainless because the connections are just clamped on hoses.

[Leif A.]

Re: 1970 Fuel Line Question L46

That would be true for brake lines and fuel lines from the fuel pump to the carb because of the flare fittings, but the fuel lines from the tank thru the frame should be trouble-free in stainless because the connections are just clamped on hoses.

That's true Patrick.

[Terry M.]

Re: 1970 Fuel Line Question L46

Couldn't any buyer order NA9, whether in California or not? And I vaguely recall that some jurisdictions (maybe NY or NYC) required CA emissions. I don't know if this was during 1970 though.

You are right Mark in that any buyer could order NA9 regardless of where the car was delivered. It is hard to tell original buyer's intentions or thinking 20, 30 or now 50 years on. Of course there are the few, the proud the original owners. My apologizes to the Corps for modifying their motto.

[Mark E.]

Re: 1970 Fuel Line Question L46

You are right Mark in that any buyer could order NA9 regardless of where the car was delivered. It is hard to tell original buyer's intentions or thinking 20, 30 or now 50 years on. Of course there are the few, the proud the original owners. My apologizes to the Corps for modifying their motto.

Cars that vent to atmosphere do stink up the garage. Maybe this was a motivation to order CA emissions.

[Terry M.]

Re: 1970 Fuel Line Question L46

Cars that vent to atmosphere do stink up the garage. Maybe this was a motivation to order CA emissions.

My 1970 does not have NA9 and has never "stunk up" the garage. In fairness the leaking Holley may have disguised any other odor.