I’ve got to replace my charge cooler pump on my XJR as it’s starting to go. I was looking at the charge cooling system layout and noticed that the charge cooler and radiator share the same cooling circuit. Meaning they’re connected and the charge cooler is being fed hot engine coolant.



The only thing my brain could think was “why” and determined the factory layout saved space and didn’t add too much complexity. I also couldn’t help but wonder how much cooling improvement could be achieved by separating the system.



Putting some research into it didn’t yield much as far as who’s done this before on these cars. It doesn’t seem like it would be that hard to accomplish. The biggest headache being the coolant tank that would need to be added and then build some lines and route them cleanly.

Every other car I’ve looked at with my own eyes has separate systems be it factory supercharged or aftermarket.



The question comes down to…



Has anyone here done this?

Is there improvement to be had as far as cooling efficiency or has my mind just wondered way off base?

 

I haven't seen this done on a Jaguar either, but the "split cooling" mod is a common mod on M113K equipped Mercedes like the E55 AMG. Implementing it would require another heat exchanger behind the front bumper and custom fabrication of mounts but it otherwise doesn't seem too difficult to do.

If you take a look at the diagrams they don't really circulate within the same circuits, they just share one point for the purposes of bleeding the circuit for ease of service. If you really want to put a dent in your IATs, install a "killer chiller" which utilizes your AC refrigerant to cool below ambient. This is what Dodge did from the factory on the Demon.

 

By the way, the ZZP intercooler pump is nearly a direct drop-in replacement for the factory pump. Just have to modify the factory harness. The factory hoses will slip over the ZZP pump inlet and outlet no problem and it even fits in the factory rubber sleeve.

 

I read that the ZZP pumps weren’t lasting. Maybe I’m mis-remembering.

 

I was thinking of removing the factory thin charge cooler and getting something all aluminum and mounting it lower to get it off the radiator and use the lower bumper opening more efficiently for the charger cooler.

 

SuperchargedXJR, I have also pondered this idea as a power gain, but also something that should help prevent knock in the car. But, lets take this to an extreme and assume that you get all these ideals. So, lets first assume that you are starting with a 575 XJ making 575 hp (the highest in the XJ lineup before modifications). Then you have the golden rule for air temps which is "10F drop in intake temp will net a 1% gain in power due to denser air. So, under wide open throttle (making maximum boost), what is the intake air temp leaving the blower (before going through the cooler)? Lets assume 250F (not sure what an actual realistic temp would be). Lets assume you can cool the air down to 100F (this is probably being generous without some sort of extra power cooler/ice bath setup). So, you have a 150F drop in temp, resulting in a 15% gain. On the 575 hp engine, you are looking at a 86 hp gain. Not a bad gain for say a $1000 investment. But, this is also probably a bit idealistic. Actual will probably be something less (not sure what it would be, 70? 40?). This is where a look at what the MB guys are getting with their setups would be interesting. Also keep in mind that you are only getting this large of power gain at wide open throttle. How often are you there? For normal drives, I am thinking that you are going to get a minimal increase which may result in slightly better gas mileage since the motor should be running slightly more efficiently. But, my big thinking is that the intake air temps are going to be down, so, the ability to get knock out of the motor is going to be harder to get.

So, in the long term, you may see some benefit from better mileage. But, it will be minimal. .

 

Just now understanding that my post sounds very much like a “I’m chasing HP” post, I will say that isn’t the case. But, a “happy accident”, so to speak, if horsepower was gained.


Last week when I saw the P0 code for “charge cooler below efficiency” - I figured my pump was going out after ten years of service. Hours after parking the car, I popped the hood and was nosing around. I immediately notice how insanely hot the supercharger still was.

It got me thinking.

If I could lower the temps of the cooler / coolant - maybe I could get some of this heat out of this thing and possibly reduce some wear and tear, maybe gain some ponies and have an overall happier engine. Having already upgraded all the cooling pipes to metal and getting the cooling system robust - the next step logically to me is increase the efficiency. Especially considering I live in a state that does get rather warm.

 

Agreed, and the IC pump dying is a common issue on these. Most people upgrade to a Bosch 010 or the ZZP pump, which is what I did.

You can also check if your car has the "Middle East" setup which includes an extra charge cooler behind the front bumper on the passenger side of the car. The lower valence will have an actual grille instead of just a vanity blockoff plate. I don't know how many cars were equipped with this extra radiator but I'd assume most supercharged variants were.

 

Yes, I have that on mine. Behind the passenger grille and the drivers is blanked off and solid. The blank area seems like a perfect place to include some kind of “ram air / cold air” feed to the intake instead of sucking air in from the radiator. Saw a guy on YouTube convert his XFR to a single intake set up from a Hellcat on the drivers side. That blanked off inlet would give a direct feed to an air box. Not sure how he doubled up the MAF sensors and how that affects anything but…I might put some design time into it. If it can be done, in-lining the two sensors that is, it frees up the passenger side to contain a second coolant tank.

I thought that was the oil cooler. That’s a charge cooler?

 

Yes, it's a charge cooler. The oil "cooler" is actually a heat exchanger between the coolant and oil, it's located on top of the drivers side front subframe.

Your factory air intake takes air from in front of the radiator, so there's no delta-T with an aftermarket setup, you'd just be placing it at higher risk of water ingress by putting it lower to the ground.

 

is this the pump people are running?

https://zzperformance.com/products/z...1f9GVd_F4moKs5


is there a difference, other than price, to this pump and the one offered by Paramount?

https://paramount-performance.com/up...r-pump-jaguar/

The way I understand the OEM system is that it runs the n a variable flow rate. I assume the connector modifications are getting rid of that in exchange for a constant rate?

 

The Paramount pump you linked is just a Bosch 010 with a $50 upcharge.

On my 2013, the pump is a constant velocity pump with only two wires, it is not pulse width modulated. The only reason you have to do some wiring is because the 2 pin connector on the aftermarket pump does not match the 2 pin connector on the Jaguar pump. It's a simple cut and splice job. Purchase this pigtail with the ZZP pump and splice it in: https://zzperformance.com/products/b...g&_ss=e&_v=1.0

The pump is running anytime the ignition is on which makes it a good way to diagnose this problem. If the engine is running, that pump behind the bumper should be humming.

 

yeah, I can’t hear mine at all. I’ll order the ZZP.

 

The twin radiators are engine coolant radiators. Not charge coolers even though Jaguar does call them that. I have been gathering parts to add the drivers side unit but they were rare from the factory and hard to find. Note also there are differences between the XF and the XJ setup.

The wheel liners on both sides of the car already have air flow grills.
These small side radiators are designed to bring the cooling air into the front duct and then out the back of the radiator and thru the wheel well liners. The heat does not go into the engine compartment.





Here is an XF setup as I have been following DeviLS with his dual AUX radiators. I stole these pictures from his thread. It's about the most detailed and informative thread I have found. He does great documentation and part numbers!
Take a look at all the great work he has done so far. Of course his XFR-S came stock with the dual AUX radiators.
Dual Aux Radiators or "inter-coolers"




This picture will help as it shows the AUX radiator connected to the radiator and the special cooling hoses needed to connect everything up.
I have circled the radiator connection.





Here is what I am still looking for because I ordered and got the hoses. Took a LONG time to show up so again I think this is all pretty rare. I have not found the duct and mounting box yet. Still not 100% sure of the part numbers as there is almost no information about this.





Supposedly this twin setup was OEM in hot climates like the middle east but I think Australia or the Southern US are plenty hot too! There was also some talk that the Diesels had this but being in the US we did not get any Diesels so again I am not sure.
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Interesting.

Mine has the passenger but not the drivers.

If the hoses and radiator are easily available but not the shroud - if someone had a factory drivers side laying around, I can 3D scan it and then 3D print a duplicate out of carbon fiber filament.

 

Just a note that the passenger AUX radiator is standard equipment on all 3.0L and 5.0L SC engines. I have never seen a car without it yet.
I will watch this thread to see how much progress you make. The stumbling block as posted above is the duct and the "mouth" section. The XF ones are close but different. How close you ask? Not sure!

I ordered the 2 hoses and I am not completely sure they are the same for the XF and XJ. Mainly because the XJ is a wider car. Since the XJ is a wider car I figured if the hoses were for the XF I could add short sections to the ends of the hose (Circled in Red) connecting the small AUX radiators. As I said in the middle of the cars it's all the same.





Here is a good picture showing the AUX radiator connections to the radiator. Both the XF and XJ use the same radiator so all the measurements on the engine and radiator are the same. In the picture below I have circled where the hoses connect to the AUX radiators.




Here is another picture from DeviLS with the AUX radiator hoses attached to the radiator.




The dual AUX radiator setup is just so rare on the XJ. I have searched a bunch and have some information but then a dead end. Be real careful about finding the DS stuff for the XJ on EBay as all the ones I have found were wrong and the guy did not know what he was selling.

Still hoping some Diesel guys can comment if their cars have the dual setup or not? If so we would need to ship it in from the UK because the US never got any Diesels. But that would be great news because Jaguar built a LOT of Diesels!
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Dual side radiator setup is not std on Diesel model either. Been seen one with dual setup Diesel on sale in Germany, propably EAU import or self made?

 

So…reading between the lines here.

When I pull my bumper to do the charge pump I need to pull the passenger side aux radiator cowl off it and 3D scan the inside of the bumper entirely and 3D scan the passenger cowl. Then mirror the 3D model of the cowl, print it, test fit, etc and offer you anyone who wants to do this 3D printed carbon fiber drivers duct work.

Or it might be easier to make an adapter to make the XF fit the XJ inlet.

I’m interested in putting some time into it…

 

Thanks Vasara as I have zero knowledge of the Diesels and had heard a rumor that it was standard issue but apparently it was not.

SuperChargedXJR that would be my assumption but with Jaguar you never know! I think the passenger side AUX radiator could be made to work on the drivers side with a few mods if that was all we can find. Many passenger side radiators to choose from too.

Hate to ask BUT with the size of the part and all the work to scan and print it. Any estimates about the cost?

Couple of pictures from my collection.
XF setup. Again big thanks to DeviLS!




This is supposedly the mythical Drivers Side XJ duct? Maybe?





One further bit of work required is that at least on my car the drivers side is missing some mounting hardware. The holes are punched in the body but the threaded inserts were not installed. I think we could install the correct riv-nuts. So look at your passenger side mounting area and then look at the drivers side. I found all the mounting hardware part numbers including the Riv-Nuts. Some of the bolts use the Riv-Nut but the others just use the spring clips with threads.

The wheel well liner was removed to see how the AUX air boxes mount to the car. The 3 lower bolts use Riv-Nuts and the upper bolt has the sheet metal threaded clip. Note; The big white plastic part is where the bottom of air filter box plastic mounting stud snaps into.




Here is how the AUX radiators attach to the plastic hosing. They have tabs that fit into slots in the top of the AUX radiator plastic duct.



Two bolts attach it at the bottom.



But I am currently stuck because of the duct and "Mouth" section. The hoses look about right and I am not worried about getting the radiator. But the mounting stuff is so hard to find. I have had a few leads but with the cost being in the multi-hundred dollar range. I never took the chance. Again most of the listings I have found that claim to be drivers side AUX stuff is not.

Here is a drivers side AUX radiator for the XJ on EBay. That is the correct part number from my research. But why does he not have the other parts? It's a used part so it was removed from a car that DID have the drivers side stuff? I have not contacted him but again from my previous experience he won't have any answers at all.
Drivers Side AUX Radiator

I sent him an E-mail anyway. Who knows maybe he does have the rest?
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It’s going to be hard to get an “OEM mounting solution” as far as molded plastic, mounting tabs etc.

At the end of the day it’s JUST a radiator. It just needs to be mounted solidly and have a proper entrance and exit path for air to flow and water to drain out and not rub against anything.

When I do my ZZP pump next weekend and have the bumper off I’ll take a look at see what I can think up. Doing 3D scan, 3D models etc is easy and free. Just my time. I have the equipment and software; even CNC machines.

The printed duct - I would just charge what the filament costs - which is very very little. I just need to find a strong filament thats impervious to water / oil / temps etc. Some of the carbon filament doesn’t like water.

So, let’s streamline this. What’s Ebayvailable and / or as new on line? Radiator. Possibly hoses.

it’s the mount and ducting that’s rarer than hens teeth?


Even if I have to CNC an aluminum mounting bracket or whatever - it would still be cheap. I’m not interested in making money. Making cool mods for these cars is what I like. No one cares about these cars and those that do charge line a wounded rhino.