Fuel Cooling?
 

After having a chat with my builder this afternoon we think that the Walbro in tank pump is probably going to be out of its depth with the s400-75 on it. So it looks like the fuel system is on the cards

He seems to be a fan of fuel cooling, said when he made his car pumping so much fuel through the std lines heated him up and was giving him major issues. What do you guys think of running a fuel cooler/do u know where to get one.

I've got a pic of how I'm planning to run the system I drew up in paint lemme know what you guys think. Looking at running one of the fuel lab 1000hp in line pumps and one of the fuel lab filters, I like how you can clean the element in them. (didn't put my in tank pump in the diagram but its there) planning on fabricating up a surge tank to go where the exhaust normally is on the r/h side of the car as I'm just running a single pipe. Is re making the return line going to be necessary or will it be ok with just the larger supply line?

http://i939.photobucket.com/albums/a...elsystem-1.png

Just had a new idea whilst in the shower. I think I might run the return line to the surge then the surge to the tank, in doing that I might get one of the fuel filters with a check valve and run it before the return enters the surge. Thoughts?

Well I had also thought of running a fuel cooler, but never got around to doing so. When I was looking at the idea I never really got the answer of placement as far as running it in the feed side opposed to the return side or the opposite. Maybe some of the guys here have a better grasp of the subject.

When I did look at the idea I thought of using the BG heat sink. There was the Flex a lite cooler as well.
http://www.barrygrant.com/news/artic...oduct_005.aspx
http://www.flex-a-lite.com/auto/html/fuel-coolers.html

I never really looked at those cool can type coolers like Moroso & Mr Gasket, I'm actually not sure if they are used in EFI cars.

Assuming the Walbro is in-tank, use it to feed your surge tank. Also, like you said, plumb the return back to the surge tank. Have a return off the top of the surge tank back to the main tank.

I'm just wondering what kind of real-world benefit there is to cooling the fuel personally. I know on the Honda F1 turbocharged racecars, they actually pre-heated the fuel to a certain temperature using engine coolant to help atomization, now whether that was to help fuel economy, power, or a bit of both I don't recall. I'm just not sure it's going to help you...

I also thought of running one using an outboard boat water-cooled oil cooler, and plumbing it in-line with my air-water intercooler. But when I looked into it I couldn't find much more benefit than just me thinking it would help.

Well I'm not planning on running one now, as I am going to make up half inch fuel lines instead. When your running big flow efi pumps through standard lines the fuel gets fairly hot and can cause issues.

My filter and pump got here today, pretty impressive took a week to get here from the states. Now all i have to do is try and get ahold of some fittings to make up my lines and i'm all set.

It seems I can wire the pump up to the ecu so once it hits a certain RPM the pump will switch to the higher output. Should be good as it will shut the thing up while cruising. It's rather massive though

Quick question for those reading. I have a walbro in tank pump, was thinking this afternoon as this is an efi pump will it be suitable to fill the surge, or do I want a lower pressure higher volume pump?

Heres a pic of the pump and filter

http://i939.photobucket.com/albums/a...r/IMG_0614.jpg

Layman here what would cooling the fuel before it goes back into the tank do for you?

the honda engine is neat, it does really highlight that the fuel they used was weird though.

i wonder how much cooling youd really need with gasoline? it might be that a loop of aluminum line, like a PS loop would be plenty

either that or maybe it would be simpler to hook up the fuel pump speed relay

Fuel coolers are used on engines that have major heat soak problems that causes the fuel to evaporate in the lines. I had an old turbo'ed Fiero and was getting bad fuel vaporlock probs, slapped an inline fuelcooler on it and it solved the prob. But that car was rear engined and had heat issues form the start. I wouldnt think in our cars it would be as big of a problem, then again ive never done any high HP builds on a rotary yet.
Ryan

i just bought a transmission cooler to try this with, im going to mount it in front of the radiator and put it between the filter and the rail. it would be nice to have some temp readings if anybody had done this before to see if its worth it?

I'm not going that far on mine. Im making a surge tank thats going to mount where the r/h half of my exhaust used to be. I'm going to have the cooler attached to that as well as the pump so it's all in one unit. Just waiting on the fittings I ordered to get here. They are having trouble getting one of the bulkhead fittings I want =(

I have every F1 book and report known to man from the turbo era, i'll try to scan that article and post it.

Fuel cooling is only needed when you have an abortion of a fuel system (read 2 x 044 Bosch LOL) then it is easy for the fuel to go over 80 deg C or more and you can see and hear it boil in the fuel tank! I have seen this first hand after a 20 minute drive in one Mazda I tuned for a work shop one night.

A proper fuel system (I.E. Mine) will support 850bhp or more in power ;) and after 30 minutes of operation only show 8 degree's over ambient temperature (with only 30lt of fuel on board). IE 20 deg C day, 30 minutes later of running fuel temp logged at the rail is 28 deg C or so. :party:

*This is achieved by no stupid base pressure settings.
*A variable speed/voltage fuel pump control
*A decent Japanese fuel pump, more flow less heat than others
*A Water Injection tank that has a fuel circuit built into it.

In practice you really need to be fucked up bad like that workshop Mazda I worked on to see a benefit from "cool fuel" but in some cars it can make the difference from detonation to not believe it or not. Power wise it makes fuck all difference.

This is my "fuel cooler"

Fuel goes in the bottom fitting, out the top fitting, in my water injection tank is a allow fuel coil, it stabilizes the fuel temperature, after a 30 minute drive the tank is still cold to touch, I have included a log of the fuel temperature on a 100kmh to 150kmh run in 2.291 seconds! 20 deg C ambient day yesterday at this test run. Fact V's Fiction lol

http://img600.imageshack.us/img600/7...1cdisystem.jpg

http://img132.imageshack.us/img132/9...2cdisystem.jpg

http://img214.imageshack.us/img214/7...ttuned20ps.jpg

This should really not be a problem with the normal (rail) pressures we're running unless you're running some kinda extreme fuel set-up - see RR's post about the multiple 044's.


-Ted