Carb to EFI - Fuel lines

I'm going from carb to EFI on the Challenge Roach (82 Corolla w/3TC)

Should I change out the fuel lines?

If so:

• What size? (Approximately 200hp and 100-188lph fuel pump)
• Metal or rubber? (covered under a protective panel that runs the lengh of the car)

What say ye??

What is the diameter of the current lines?

Is there a feed and a return line?

I'd have to crawl under there and measure. I'm betting dinky . . . LOL!

There is a feed and return line.

EDIT: .25 feed and .20 return OD fuel lines

The fuel line material depends on the fuel pressure it will see. If the high pressure pump will be in the tank or near it then either metal or high pressure capable rubber/plastic line from the pump to the engine.

In reply to jimbbski:

I'm leaning towards an external unit that will be mounted next to the tank. 6-8" inches away from the outlet line about the same height . . .

I never knew about the difference between carb spec and FI spec. Glad I found out before I put the NB engine in my NA. Harder to find, but well worth it. Not a fan of fires!

Strike_Zero wrote: I'm going from carb to EFI on the Challenge Roach (82 Corolla w/3TC) Should I change out the fuel lines? If so: - What size? (Approximately 200hp and 100-188lph fuel pump) - Metal or rubber? (covered under a protective panel that runs the lengh of the car) What say ye??

200hp from a 3TC without boost??? Not likely, not cheap....

The stock lines are a we bit small, but should be adequate for 140hp, which is far easier, although still tough to make N/A.

The AE86 EFI lines do mostly fit the bottom of a E7 Corolla, so you could run a GTS line, that is what I'm using on my 170hp 4AGE with no issues.

Finally, you can but large diameter metal line... OR EFI capable rubber fuel line

TiggerWelder wrote: I never knew about the difference between carb spec and FI spec. Glad I found out before I put the NB engine in my NA. Harder to find, but well worth it. Not a fan of fires!

Yup, quick way to tell, is if the parts store doesn't charge around $5/ft then it likely isn't EFI rated.

Also, the return line isn't under pressure (usually) so you can run less expensive hose for that, but that's your choice.

Strike_Zero wrote: I'd have to crawl under there and measure. I'm betting dinky . . . LOL! There is a feed and return line. EDIT: .25 feed and .20 return OD fuel lines

I suspect you'll want to move up in size a bit. You could probably use the .25 line as a return to potentially save some money/effort, but if you have to bend line another one sometimes isn't a bad deal.

I would use as much metal line as possible since it flows better and there is less chance for failure, if its properly supported and bent.

In reply to oldeskewltoy:

Boost to be included

So it looks like I'm safe for testing and tuning while NA until the turbo is added . . .

Strike_Zero wrote: So it looks like I'm safe for testing and tuning while NA until the turbo is added . . .

A swirl pot in the engine bay with the EFI pump can also alleviate the need to upsize the lines from the tank, since you'll be dumping the returning fuel there and merely feeding the tank with a lightweight lifter pump from the tank (depending on your economy, you could even empty the rear tank and run drag passes or autocross runs carrying less weight in the car).

I guess I should have said the Roach will be autox'd . . . A lot!!

In reply to Stefan (Not Bruce):

Would that work using the mechanical FP as a lift pump??? Or just dump the mechanical unit altogether?

Tank => filter => mechanical FP => swirl pot => filter => hi press pump => filter => rail => regulator => swirl pot??? Or am I making this way to berking complicated (I'm good at doing that) . . . .

I have to see how much room in engine bay I have to play with. With charcoal canister relocated, that may work!!