Fuel Coolers? Who Knows Stuff About Them

[DJRIFT]

Ok sorry for somthing that should be in the forced induction part of the site but there seems to be plenty of clever people in the motor sport section.

Ok so after chatting with a mate last night he told me he was having trouble with his fuel getting too hot in his surge tank and causing the cars power to die off. he was recommended that he fit a fuel cooler. his car is a 300odd kw Rb25 in a R32 that is used for Drift mainly just for some back ground info.

i was a bit blow away by him saying that for 2 reasons. 1 i have limited experiences but Ive never seen or head of it before in similar cars in similar circumstances. ie i know of plenty of circuit cars that have never had this problem.

and 2 another friend of mine has a similar issue with his car as far as after an hour of spirited driving the fuel pump and surge tank gets hot to touch and than he gets a drop in power.

Is it somthing to do with the size of the surge tank or the plumbing of the tank because i can think of half a dozen R32s that have surge tanks, similar power and do a similar amount of work and only 2 out of 6 or more have dramas?

Can any one shed some light on what mainly causes it besides under bonnet temps?

On a side note i do remember one or two of the V8 super Taxis teams being pinned for running the fuel lines through a drink or suit cooler in the car to give them a slight power advantage. If colder fuel is better (more power) is it worth cooling the fuel for the end result?

i know ive asked lots of questions but ive just never seen or heard about it in the amount of cars that are about.

thanks Damo

[BezerkR32]

hey mate, this was touched on before in another thread, might have been Duncans build.

Basically it is caused by the circulation of fuel. A smaller surge tank could contribute to higher temps, also higher fuel pressure. It has always been an issue. we used to sit dry ice around fuel tank in drag car. Running a cooler in return line is a goog idea. Also fuels with higher alcahol content like E85 help.

[fatz]

fuel return from engine to top of surge near the drain back

fuel supply from tank to the bottom of the surge

disco!

and make sure your lift outflows your engine fuel pumps

[Neil]

I like the idea of fuel coolers and I'm going to instal one on my car.

I personally think there's way to much under-bonnet heat and all this supplying and returning of fuel just generates even more.

Here's some pics of the cooler I'll be using,,,It's out of BMW X5 diesel (E53 1st gen).

Neil.

[DJRIFT]

WoW thanks for the feed back.

i dont think i need anything for my car just yet but it is now on the to-do list for my car.

and i will be monitoring some of the circuit racing skylines to see if its a problem for them.

After talking it over with a few mates we realised that it happens to two blokes that have high mount turbos in r32 gtst with stock bonnets where as most of the circuit r32s have vented bonnets. that may also be a cause.

[sav man]

where about are you going to mount it on the car neil? under the car near the diff?

[badhairdave]

i never had an issue with my r32 on a track or the street and it had similar power to the ones you mentioned.

walbro lift pump, 1.5 surge tank, 044 main pump.

plumbed in as fatz has mentioned with the lift pump easily out flowing the main.

The car would happily do 20 minute sessions around wakefield in 30+ temps with no fuel issues. The tyres would over heat before anything else.

It also ran a stock bonnet.

The surge tank would get warm to touch but never hot.

Ideally the return should be plumbed into the fuel tank but as that's a PITA we all tend to just run it back to the surge tank. If your lift pump isn't out flowing the main significantly so the fuel is constantly being recirculated through the engine bay then you will end up with the problem you have mentioned. If the lift pump is easily out flowing the main then the fuel is constantly getting returned to the tank and getting a chance to cool down.

[Evocoop]

Another little trick I've picked up from experience is to recycle the old oil cooler from the Hicas if you've removed it. After it's out of the reg run it through the factory power streer cooler and back to tank. It's neat, costs nothing and works enough to make a difference.

[Neil]

where about are you going to mount it on the car neil? under the car near the diff?

Ben,,,on the Radical it's going where the vent is in the pic. I'm going to replace the vent with a little scoop. I'm hoping that Duncan's class rules allow for one as well.

If they do I'd like it in the engine bay on the supply line.

Skylines shouldn't have a problem with hot fuel,,,I'm quessing theres another problem. BUT cooler fuel means more horsey's so why not run one. Feel the fuel rail next time,,,man it's hot.

Neil.

[Duncan]

yep coolers are free for me. I'll run a temp gauge around the fuel line before adding the weight though

the nugget on the other hand should probably get one from day one.

[DJRIFT]

Another little trick I've picked up from experience is to recycle the old oil cooler from the Hicas if you've removed it. After it's out of the reg run it through the factory power streer cooler and back to tank. It's neat, costs nothing and works enough to make a difference.

after looking at one of the cars in question we thought about this option as it would look very stealth but i dont think it will be enough. but i am thinking about re-fitting my old P/S cooler there and plumbing it into the return because as you say its cheap and easy and weighs f all.

[eric liu]

all of the topic seems very difficult to me ,haha

need to know more about it

[unique1]

i run a single 044 feeding a 3l surge tank into twin 044s and after 30 min of driving the pumps get alot louder and the surge tank is pretty damn warm, i will be adding a fuel cooler on mine for sure, the cooler the fuel the better

[BezerkR32]

you know that too much pump will also contribute to the problem.

i run a single 044 feeding a 3l surge tank into twin 044s and after 30 min of driving the pumps get alot louder and the surge tank is pretty damn warm, i will be adding a fuel cooler on mine for sure, the cooler the fuel the better

[unique1]

you know that too much pump will also contribute to the problem.

yes i know that, the setup was in a street car before when having the issues of noisy pumps but now its going into a track only car and it needs the pumps, one 044 wont cut it so 2 is needed for the power output i am running.

Edited May 22, 2009 by unique1