Getting more air onto my oil cooler. Bumper mod?

[jonrb 0]

Hi folks

 

I need to get more airflow onto my oil cooler which is located on the N/S behind the bumper. It is currently fed by slots dremmeled into the fake grille next to the N/S towing eye cover on my VR6. For track days I can get a little more airflow onto it by taping the towing eye cover open, but I still see 140 degC on track which just isn't good enough. Taping the towing eye cover does make a significant difference though as it takes much longer to come up to that temperature, so I know I'm on the right lines here.

 

I'd like to replace the entire fake grille with a duct or scoop, does anyone know if a) the grille comes out easily and b) if any such duct is available?

 

Thanks in advance

Jon

[Toad 0]

Early cars had a pipe that took air to the brakes to cool them that was fed from that part of the bumper. would be worth looking at them I believe.

 

Here's a poor pic of the duct and an early lower grill. Alternatively how about putting it in the cetre of the bottom of the bumper?

[jonrb 0]

Mine is a very late VR6 - last of the line, first registered in 1996.

 

However, my grille looks pretty much like what you have posted and ringed in red. Only on mine the grille is all fake and blanked off and Stealth opened up some of the bars of the grille with a Dremmel.

 

If that entire grille could be opened up, or even temporarily removed each time I go on track, then that might do the trick.

 

Does anyone know if it comes off easily on its own?

[craziscot 0]

If your hiting 140 Deg C on your oil temps your lucky you've not blown the engine to pieces!!! I'm sure oil looses it properties and consistancy at about 130 Deg C!!!!

[boost monkey 0]

If your hiting 140 Deg C on your oil temps your lucky you've not blown the engine to pieces!!! I'm sure oil looses it properties and consistancy at about 130 Deg C!!!!

 

Depends entirely on what oil he is using (grade and quality) but you're right on the basis that oil starts to break down at high temperatures.

 

OP, what oil are you using and what cooler? 140dec for oil temp sounds a lot higher than a stock VR should be getting. When did you last flush the oil and do a change?

[Toad 0]

ooooh on a related note... have you got vag com? Can you let me know your ecu part number, mine is a similar vintage, but seems to have a golf ecu, but so is another late vr I know of. I wonder if they put golf ecus on the last few vrs.

 

That pic is of an early bumper. Maybe you could get the grill to fit yours? Otherwise just Cutting that section right out would probably do the trick :)

[jonrb 0]

I'm running Silver Synta oil (as supplied and fitted by Stealth) and topped up with Castrol Magnatec as I was low on oil recently and didn't have any Synta.

 

I plan to change the oil before my next track day, BTW.

 

Not sure what the oil cooler is as Stealth did a supply and fit - I think it's a Mocal.

 

BTW, I'm only seeing these temperatures on track with some very hard driving - not on the road!!!

[jonrb 0]

You can see the actual install on this pic:

 

s_Image025.jpg[/attachment:ec663]

 

So for ultimate cooling I guess it could do with ducting making two air paths - one each side of the cooler.

[Dec 1]

I have the passenger side ducting off an early spec car going spare, let me know if you need it. :wink:

[jonrb 0]

I have the passenger side ducting off an early spec car going spare, let me know if you need it. :wink:

Yes please - it might be useful. I'll drop you a PM.

[jonrb 0]

I've had a better look at the bumper now.

 

You can clearly see the oil cooler almost side-on through the slots cut into the fake grille, so finding a way of opening that up more would definitely help.

The "slats" of the grille are wedge shaped, so the gaps in the grille are much smaller than they look.

The grille runs the whole width of the bumper. If you cut that area out then the cover for the towing eye wouldn't stay on any more as it clips onto lugs either side, the N/S of which is on the part I would want to remove.

 

I don't understand why the earlier design (posted by Toad) has proper functioning grilles and why the later one is all blanked off and fake. :(

 

I've looked on Demon Tweeks and, whilst they have a good range of ducts, they're all too big for the gap. I think realistically I'm looking at buying a Dremmel (finally, an excuse to buy one!) and cut out the slats of the grille to leave an ugly hole, smooth down the edges as best I can and maybe fit some coarse mesh to prevent stone damage to the cooler.

[Rob Heath 0]

What about fittin a bigger oil cooler??

[jonrb 0]

What about fittin a bigger oil cooler??

I think the oil cooler is probably sufficient if only I could get more air onto it. When I tracked the car for the first time with it I was dismayed how ineffective it was. However, taping open the towing eye to make an impromptu air scoop made a massive difference - I still got silly temperatures but it was more slowly. So I figure that if I can get even more air in then it might do the trick.

 

Also, I've only just had it fitted, so changing it for a bigger one already does seem like a bit of a waste. :)

[jonrb 0]

This is what I've come up with for now. I used a drill saw to just cut the whole lot out. It's not pretty but it does the job. I hope it doesn't affect the aerodynamics of the car too badly.

 

oil_cooler.jpg[/attachment:baf81]

 

I'm not sure what that tube is. I'll have to find a way of clipping it up out of the way.

 

At some stage in the future I'll buy a replacement lower grille andcarefully cut out the back of the blanked-out portion with a Dremmel to leave it looking like Toad's one.

[jonrb 0]

For reference, the "tube" is part of the wiring for the fog lights.

 

Interestingly, I was talking to the guys at The Phirm and they say that they mount the oil cooler behind the upper grille, in front of the main radiator, because

a) there is room,

b) there is plenty of airflow,

c) less chance of stone damage than where I have mine and

d) for maximum airflow on track days it is very easy to just unclip and remove the entire grille.

 

I may have mine relocated.

 

In the meantime, my hack about on the lower grille did work well, although when I used it in anger at Silverstone it was a much colder day than previous track days which would have helped anyway.