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Posted by: Conceivedready61 Sep 19 2021, 01:49 PM

Hello All: Not sure if this question has been addresses here as I couldn't find it, But,,,, I'm doing a V8 conversion in my 914 with a late model GM L83 aluminum block that has direct injection. I have purchased an in tank pump( Holley Sniper) to supply the direct injection pump on the engine. This is a non return type system, although the pump has ports for Return and a Vent, the return is plugged in this scenario. My question is with this do I need to keep the Yugly Fuel expansion tank?? Also where does the Vent go from the intank pump?

Thanks in advance for any help.....

Posted by: Tdskip Sep 20 2021, 06:02 AM

With that set up I believe you can plug the return lines.

The tank should have some ability to vent, but that doesn't have to be the factory set up. Just make sure you don't end up with a car/garage that smells like fuel.

Posted by: davep Sep 21 2021, 04:55 PM

The expansion tank is there for a reason, and should not be removed; do so at your own risk. The same with the charcoal canister system, but to use it properly you would need a new source of pressurized air.

Posted by: SirAndy Sep 21 2021, 05:15 PM

Hands down the worst thing i ever did to my car was to remove the expansion tank and charcoal canister.

I'm now running a hose straight from the filler neck vent down under the car and every left hand turn, with 1/2 a tank of gas or more, gas is dripping out the vent and i have a strong gas smell inside the car.

Posted by: eric9144 Sep 21 2021, 08:32 PM

Same, actually pulled over on a twisty road because the gas smell was so strong I thought I had a big issue....not something you want happening on the regular if simply keeping some of the gear in place handles it gracefully.

Posted by: windforfun Sep 21 2021, 08:42 PM

Why do guys make these potentially lethal modifications to your car? Are you engineers or just mechanics? These systems were designed the way they are for very good reasons. I just hope you don't burn your house down in the process. Too much free time perhaps?

Posted by: FL000 Sep 21 2021, 08:45 PM

I recommend keeping as much of the expansion tank / charcoal setup as possible. I have a similar setup as you but have the fuel return also. I ditched the expansion tank but preserved the charcoal canister. I route a hose exiting the canister to my air cleaner.

If I fill the tank up to the brim I get a slight smell of gas the first few miles which I can live with. Without the canister there is a more persistent smell.

Maybe better ways to do it but works for me.

Posted by: andys Sep 21 2021, 09:22 PM

Ditto; I did the same to retain the expansion tank as well as the charcoal cannister.

Andys




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Posted by: Chris914n6 Sep 21 2021, 10:37 PM

A returnless system has the after fpr/return built into the pump assy so it just dumps back into the tank. Less heat transfer from the engine this way. Don't block holes.

In newer cars the charcoal canister doubles as the expansion tank. You will need something or the tank pressure releases to atmo and you smell it.

Posted by: Mikey914 Sep 23 2021, 04:52 PM

I have to ask, why reinvent the wheel?
Is there some performance increase? Some other factor that outweighs the cost, and engineering required to make the system to work safely?

If it’s simply price problem (ie you have a 3 port pump and it’s $900), why not pick a more proven solution that has benefits in other areas.

If this is the case relocation of the fuel pump to the front, under the tank, is less expensive, proven, and helps with vapor lock. There are several threads here on it. I consider it a best of all worlds. When I did my 72 it cost me less than $200 and I replaced all the rubber hoses.

Hope you find this helpful.