I have just fitted a low profile number plate to the front of my 2002 XKR but am having concerns regarding air flow to the cooling system’s behind the grill. As it is currently winter here in Australia there is no real urgency regarding this potential problem.

Prior to purchase the number plate was fitted in the same position (in front of the grill) so to cover the many holes in the black vertical supports I did the same. I am just wondering if this will be a problem later in the year when the temperature increases. Any comments or help regarding this will be much appreciated.

 

You are blocking 40-50 % of the air coming in the grill. I would do whatever needed to get the tag plate lower and out of the grill as much as possible. These cars don’t have enough air flow already with nothing in the grill. Blocking off the grill even partially needs to be avoided as much as possible.

Z

 

If the previous number plate was fitted in the same position across the rabbit ears and the car suffered no ill effects, then I would expect the same to apply, especially if the new plate is "low profile" compared to the previous one.

Richard

 

Hard to say, I used to have a sticker plate but was fined for it so I put a new plate on a similar position to what you have now. I've not noticed any difference in temps although restricting airflow is never a good thing ideally. I only know from cooling for radiators in a desktop PC and you would be surprised what little effect cables and things in the way of a fan actually has. It's very minimal unless you are actually blocking the path entirely. The V600 Aston Martin V600's have a more restricted airflow and they don't seem to suffer with cooling problems for such a large engine so I don't think we really have much of a problem although it doesn't hurt to drill a couple of holes in the number plate to lower it a little. AM_Vantage_LeMans.jpg (2256×1252) (wikimedia.org)

 

I recently lowered my number plate on my 98 XK8 to help show off the shape of the whole intake. Admittedly my car has the traditional overriders and the chrome strip. One thing that I noticed was that there is in fact only a small open slot at the top and a much larger one at the bottom. Also there is a substantial intake underneath the grille. I really don't think that your plate would make that much difference to the amount of air entering the front of the car to be honest. My assumption is that behind your wire grille, the structure is similar to my XK8.

 

The other extreme. The aluminum cross beam has now been painted black to loose the toothy-ness.

 

When I got rid of the two teeth and their supports my highway temperature @ 65-75 mph fell by 7 degrees F. Over 80 mph the temp has always dropped by 5-10 degrees and continues to do so.


the dropping of coolant temperature when the speed is over 80 mph has always indicated to me that the car would benefit from a larger opening for airflow.




Z

 

Thanks to everyone for their input and help, to maximise the cooling and for my peace of mind, I have decided to lower the plate so as not to restrict the flow of air through the grill.