Fuel cooler placement, R34 GTT

[chiksluvit]

Fuel cooler placement, R34 GTT

Hi all,

Having rewired the fuel pump, the 040 buzzes pretty hard when the fuel is warm, usually only takes less than 30 min drive in summer and maybe under around 1 hr in winter before it starts screaming, so I thought I'd add a fuel cooler on the return line.

Trying to find somewhere to put the fuel cooler wasn't easy though, basically a few things I had in mind:

• not drilling any holes on the chassis
• not keen to put it in front of the car- explosions on collision

The best I could find was under the floor pan below the drivers seat along the chassis rail- what do people think of this location?

this is where I found:

 

[chiksluvit]

And here's a photo of the cooler test fitted



Haven't finished making the bracket yet, will make a bracket to hold the fuel cooler to the sill once I'm sure that's where I'd place it. Any feedback on potential hazard or suggestions of other better location is welcomed

Placement of cooler was inspired by vw golf diesel models

[GTSBoy]

If that's as flush to the floor as I think it is, then you need to change it so that it gets some air flow through it.  Move it away from the floor, make a small scoop of some sort to duct air to pass through it either going up or down, depending on nothing more than preference.

It is true that it will do some cooling as you have it......but it could do a lot more.

[chiksluvit]

Thanks GTSboy, thought about making an aluminum duct for it and slightly angle the rear side down so air will have somewhere to go
But do you see any potential hazard? Like rocks hitting it or do you think it's unlikely?

[GTSBoy]

There's the beauty of the scoop.  It can also be a pretty effective shield.

[DCIEVE]

Some fine mesh would be wise, plenty of stones bounce around under the car.

[Skepticism]

I worry a bit about what happens when you go over a rumble strip at the track, or scrape on a driveway, or something :s

 

Edited February 14, 2017 by Skepticism

[chiksluvit]

Hrm it sits slightly above the bottom of the chassis rail and the side sill. Plus the car isn't that low, so im not so worried about the height. You can see from the photo that the dump pipe and gearbox both sits lower than that and Ive never had clearance issues

Most Volkswagen diesels have their fuel cooler sitting at the bottom like this, albeit different style and positioned in between two rails which is probably more ideal

[V28VX37]

I'm with GTSBoy in that it won't do much without airflow, especially is butted against the floor ppan . you'll definitely need a scoop which will add height and complexity.

Suggestion: how about just a bigger capacity fuel pump with good large gauge rewire? Theoretically it would run at less capacity and cooler & quieter. Safer too compared to an external cooling core.

I've got a small Walbro 270 and it's noisy as anything on a track day but does calm down afterwards. I'm assuming 040 is of a similar capacity. Try Walbro 460 or something perhaps?

[GTSBoy]

4 minutes ago, V28VX37 said:

I'm with GTSBoy in that it won't do much without airflow, especially is butted against the floor ppan . you'll definitely need a scoop which will add height and complexity.

Suggestion: how about just a bigger capacity fuel pump with good large gauge rewire? Theoretically it would run at less capacity and cooler & quieter. Safer too compared to an external cooling core.

I've got a small Walbro 270 and it's noisy as anything on a track day but does calm down afterwards. I'm assuming 040 is of a similar capacity. Try Walbro 460 or something perhaps?

Actually, that makes it worse.  Bigger pumps push the fuel around through the rail more often (picking up more engine bay heat) and they beat the crap out of the fuel in the pump itself.  A proper voltage control system is the best way to make the best use of bigger pumps.

If it were me, I would be putting it towards the rear of the car.  In front of the rear axle, opposite side to the exhaust.  About where the HICAS solenoid would be on an R32 if it was still there.  But even further tucked up.  Track GTRs used to run diff coolers there.

[sneakey pete]

There's not really much space there with the 33/34's because the fuel tank sits there now.
If it were me i'd invest in PWM fuel control and stop the fuel from getting hot in the first place instead of trying to cool it down after. Easier said than done of course.

[chiksluvit]

Yeah I had that location in mind at first but unfortunately it's where the fuel tank sits on the r33/34, the floor pan in front of the tank is also lower than the front, so the lowest point of the cooler will be sitting lower than the bottom of the chassis rail and be as low as the bottom of the exhaust

 

Here's a photo of it when I first trial fitted it

 

 

[GTSBoy]

[Dose Pipe Sutututu]

Looks much safer behind the diff like the above photo.

Flying off the track and hitting a ripple strip with the fuel cooler exposed next to the chassis rail would be dangerous.

[Dose Pipe Sutututu]

also what potato still runs HICAS on a fairly worked car? (referring to the car with the fuel cooler mounted under the spare)

[niZmO_Man]

Hey man, HICAS has its uses

[Dose Pipe Sutututu]

18 minutes ago, niZmO_Man said:

Hey man, HICAS has its uses

I guess so, as a boat anchor (small boats) or a door stop, could also use it for bicep curls

[chiksluvit]

I think GTSBoy's photo is referring to the cooler in front of the rear sway bar. I'm not sure how that is mounted but I'd imagine it will need some drilling on the floor pan, likewise with mounting behind the diff

I initially found this and was planning to copy this but found out it was for r32 gtr and won't work on r33/34 due to the location of fuel tank



And here's the Volkswagen/Audi set up- similar to where I've placed it, except it's a lot slimmer than the cooler I've got..

[Dale FZ1]

VW use a completely different cooler design.  If you're focused on running a cooler, look at the spec/type they have used.

Otherwise, really consider what Sneakey Pete has recommended.  Better approach all-round IMO.

[sneakey pete]

Just had a thought: you running this in the feed or return?

If the pump is heating it would need feed, if the going through the rail and getting hot is would need return, i'd have thought?