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Fri Jul 25, 2025 11:16 am

Greetings! I just got my project going after trying every combo known to man or me anyway. Right now I have a issue with the fuel system. I'm about to go out and tear into that. I think I have the pump too far from the tank (14,16") I'm getting cavitation in the pump. It'll be running great, hit a bump goes to missing afr goes into the 20's! My question is what are the alcohol injection diy'ers doing for intercooler? I'm not really far enough into my tuning to see any boost yet. So I have a 7lb fixed gate on my turbo. As soon as I get this fuel problem sorted out I'm sure the boost will follow! So anybody with a megasquirted vw let me know what yall are doing!
Thanks
John

Fri Jul 25, 2025 11:58 am

This pic is not my car but, I do own this Turbo Intercooled EFI setup. I bought it from the builder a few years back.
I just haven't been able to get around to fitting the system on my engine. :?

Fri Jul 25, 2025 12:31 pm

Vegaphred wrote: Greetings! I just got my project going after trying every combo known to man or me anyway. Right now I have a issue with the fuel system. I'm about to go out and tear into that. I think I have the pump too far from the tank (14,16") I'm getting cavitation in the pump. It'll be running great, hit a bump goes to missing afr goes into the 20's! My question is what are the alcohol injection diy'ers doing for intercooler? I'm not really far enough into my tuning to see any boost yet. So I have a 7lb fixed gate on my turbo. As soon as I get this fuel problem sorted out I'm sure the boost will follow! So anybody with a megasquirted vw let me know what yall are doing!
Thanks
John

Are you using one of those Tee's for the return line that screws onto the bottom fitting on the tank?

Brian

Fri Jul 25, 2025 4:10 pm

I had the same problem with 2 different fuel pumps, changed pre-pump filters, post filters, hose sizes, mounting locations, etc, etc... Finally purchased a fuel pump that sucks fuel vs. gravity fed and put the return line into the filler neck of the fuel tank and have never had an issue since. Several thousand miles and 17 psi of boost.

Just sayin' if you are interested.

M

Fri Jul 25, 2025 4:56 pm

Lots of issues with trying to return the fuel into the feed line.

You should be returning the fuel back deep into the tank so it have a chance to cool, and work the bubbles out.

Brian

Fri Jul 25, 2025 9:35 pm

Vegaphred wrote: Greetings! I just got my project going after trying every combo known to man or me anyway. Right now I have a issue with the fuel system. I'm about to go out and tear into that. I think I have the pump too far from the tank (14,16") I'm getting cavitation in the pump. It'll be running great, hit a bump goes to missing afr goes into the 20's! My question is what are the alcohol injection diy'ers doing for intercooler? I'm not really far enough into my tuning to see any boost yet. So I have a 7lb fixed gate on my turbo. As soon as I get this fuel problem sorted out I'm sure the boost will follow! So anybody with a megasquirted vw let me know what yall are doing!
Thanks
John
Does your tank have a vent? I had a fuel flow issue many years ago caused by no vent in my tank.
Currently I'm running an in tank pump, completely homemade, I wouldn't duplicate it today, with the parts that are available, but it's been in the car for 10 years now and has been completely trouble free. The only downside to an intake setup is having to to figure out what to do with the fuel line(s) coming out of the top of the tank. My return is to the stock output on the bottom of the tank, tapped for 1/4npt and adapted to a 90° -6an to work with the hardware running into it. The pump is nice and quiet, also there is a huge selection of cheap in tank style pumps on the market, you just have to be a little creative when designing the system initially.

Your question about alcohol injection and intercoolers is confusing. Are you asking about water meth injection or are you interested in intercooling an engine currently running on e85, or are you wanting to install an intercooler on your e85 burning, water meth injected setup?

Fri Jul 25, 2025 11:50 pm

Another idea you could look into is using a low pressure feed pump and a swirl pot near the engine with the HP return to the pot. The fuel return to the tank comes from the top of the pot, the fuel feed to the HP pump comes from the bottom. So any air bubbles are returned before they reach the HP feed.

Alternatively just make sure the fuel return goes back somewhere any air bubbles can not reach the intake to the HP pump.

I am going to return to the fuel filler on my RusEFI setup.

Sat Jul 26, 2025 7:40 am

Chip wrote: ……
Your question about alcohol injection and intercoolers is confusing. Are you asking about water meth injection or are you interested in intercooling an engine currently running on e85, or are you wanting to install an intercooler on your e85 burning, water meth injected setup?

I thought the same thing

Thu Jul 31, 2025 4:05 pm

I don't have room for an intercooler so I'm thinking water/meth injection operated by a Hobbs type pressure switch. Only comes on under boost. I'm looking for ideas as far as design of the spray nozzles. I have dual tbs.

Fri Aug 08, 2025 7:25 am

So I drilled a hole in my tank close to the fill inlet installed a -6 bulkhead fitting and ran my return to that! Everything working as it should! No more gas fumes! Had a good day at the dyno, made 172hp! I'm looking at the water/methanol injection system from snow. What is anybody using on theirs?

Fri Aug 08, 2025 7:44 am

Vegaphred wrote: So I drilled a hole in my tank close to the fill inlet installed a -6 bulkhead fitting and ran my return to that! Everything working as it should! No more gas fumes! Had a good day at the dyno, made 172hp! I'm looking at the water/methanol injection system from snow. What is anybody using on theirs?

Using an older AEM water injection kit with new V2 injectors.

Started out using an Edelbrock system from the 80's, those were the days!