Bonk's EFI tank (rewind)

[wrcbonk]

Hey guys, I moved this over from Fuel Delivery b/c I wasn't getting any response. Not sure if thats becuase no one saw it or b/c my post sucks, we will see. I have been working on my fuel tank and fuel delivery system for my RB25 swap. I have a 1971 240. I measured the stock RB fuel lines at the rail/regulator and got 5/16ths. I am replacing the stock 1/4-inch return line off the 240 with a new 5/16ths line to match the RB. Plan to use the new 5/16ths line as the pickup and the original 5/16ths line as the new return. I drilled out the stock return line to fit a bulkhead fitting for the new pickup (see pics below). Does anyone have a suggestion of how I should seal that bulkhead fitting? I also have a bulkhead fitting for my pump electrical leads coming out of the tank.

 

As far as the delivery part goes I still need to make up my mind on an external pump or internal pump. RIght now my set-up is in-tank. I want my car's fuel delivery system to mimic the system out of the doner skyline, which used an in-tank setup. At this point I can still change and go external. That is my main question for you Hybridzers.

 

We all have that buddy who is a professional mechanic. Mine likes in-tank pumps because he claims the fuel cools the pump and noise is reduced. The same guy had a 240 for while, but then sold it. He gave me his tank for free so I felt like I could take a chance trying to modify it while still having my tank in case things blew up.

 

In order to keep things from blowing up literally the first thing I did was have the tank hottanked in muriatic acid. After that I painted it to keep the external corrosion down, then I used the Kreme product to coat the inside. I ordered the stock RB25 in-tank pump, a blind plate for access, some bulkhead fittings for the pickup and electrical, and finally a one way ball valve to resist starvation. The blind plate was a pain. I could not get anyone to sell me a nut ring so I had to make one myself. I used sheet metal and threaded inserts. It sucked, but it appears to work.

 

Then came the fun part, cutting into the tank. Its pretty amazing what a guy can do with a cut off tool, a dremel, and a set of step bits.

 

 

 

 

 

So I have two questions:

 

1) Am I just asking for trouble going with an in-tank setup or do you guys think this will work well?

 

2) How well do bulkhead fittings seal? Is there a sealer I should be using? (RTz already suggested Tank Repair material)

 

Oh yeah, I plan to put a filter in the engine bay inline with a fuel pressure gage.

 

I want to thank Monzter and 1-Tuff-Z for their posts on the subject.

 

Bonk

[PapaSmurf]

I love it, keeping the original tank is well worth the trouble as far as I'm concerned. A few things to think about: you probably should have done the cutting before having it hot tanked and sealed - obviously it should have been cleaned out well before cutting but now there may be remaining bits of metal in there and the sealer isn't there over the edge of your cut. Also does the in tank pump have a good filter on it? You want to protect your fuel pump. The in tank pump should be considerably quieter than an inline pump, my inline drives me insane. I would also put your inline filter ahead of your pressure regulator to protect it, is it a good regulator or a cheap aftermarket one?- does it have a bypass valve going into the return line? If it doesn't have a bypass line it has the potential to LEAK fuel when it goes out. I love the tank though good work keeping her looking stock.

 

*edit - Oh I misread your post, you're putting a filter inline with a fuel pressure gauge. Make sure your fuel pressure gauge is NOT the stupid variety that requires a fuel line to enter the cabin and connect directly to the gauge. Unless the gauge is staying in the engine bay make sure you buy the type that uses an electronic sending unit. If it's just a cheap gauge to monitor how the regulator is working from time to time again make sure the filter is in front of it, you don't want anything but fuel going into the guage or regulator. A fuel leak in your engine bay can really ruin your day.

Edited August 15, 2010 by PapaSmurf

[wrcbonk]

Papa,

 

You are correct about my setup. The plan is to have the filter in the engine just infront of the inline fuel pressure gage. I am not plannng to have a fuel pressure gage in the cab, I just want to be able to check the pressure in the engine bay to check the pump. After the pressure gage the line will run to the stock fuel pressure regulator, which immediately precedes the fuel rail. Need some input on what you mean by a "bypass" line on the return. As it is now the return comes off the back end of the fuel rail and just heads back to the tank.

 

Thanks

 

Bonk

[jakeoster]

Cool setup!

 

Only suggestion I would add is it would probally have been better to get a higher flowing pump. Unless you are just planning on keeping the turbo stock or mild.

Edited August 16, 2010 by jakeoster

[wrcbonk]

Jakeoster,

 

You pegged my setup, dead stock. If decide to get more agressive with my engine in the future i will need to spend the money on a Bosch 044 and maybe add some more baffling to the tank, maybe even a fuel cell. Hate to lose the spare tire though.

 

Bonk

 

Cool setup!

 

Only suggestion I would add is it would probally have been better to get a higher flowing pump. Unless you are just planning on keeping the turbo stock or mild.

[bumble zee]

I got a sump from Summit Racing and put it on my 240z tank

 

 

 

 

[rejracer]

Bill,

 

I forgot to give you the metal plate before I took off, have not forgot. I would get that plate replaced with a heavier gauge, I don't think it will seal long term. I'll get the metal to you this weekend, then we can make one, once you decide on a thickness. The heavier steel will weld up much nicer, and without the warpage.

 

My understanding of the components in order as the fuel would see them.

sock filter to protect the pump

pump

main fuel filter

fuel rail

pressure regulator

return to tank

 

keep up the good work

 

Robert