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Kudos on your absolutely fantastic work! It's stunning, and I can only imagine the smiles the car gives you every time you drive it!
One question that came to my mind was whether you considered a thermally-activated switch for the Bosch coolant pump rather than the manual fog lamp switch activation?
@Don B - Thanks for the reply. I have indeed given this a lot of thought and I'm thinking the water pump relay needs to be controlled by the IAT temp. I'm assuming the IAT outputs a voltage representative of the temp. I could build a electrical circuit that would close the supply relay at a certain voltage and open it when the temp condition was met. An easier, but more expensive solution would be to use the piggyback controller's aux inputs and relay outputs to control the pump. Setup an "IAT table" and effect a relay contact closure or opening when certain temperature conditions are met. The AEM F/IC6 at $500 would make an expensive relay controller. The upside is I could also use it to continue to log boost levels and other engine functions if the piggyback ECU just installed for data logging and to control the intercooler pump relay. Currently, at speed, the intercooler so cool condensation forms on its surface; is cooler better? Maybe at high boost levels in open loop. If too cool, could that lead to a "rich" fueling condition? MAF+ IAT + Coolant Temp Sensor + TPS = STFT Having an automated pump solution would at least control one of those variables, it would also avoid me forgetting to turn the intercooler pump on; I seem to do that quite a bit... FYI- I'm running blue coolant in the intercooler system and green coolant in the engine's cooling system to help identify what system is leaking if ever.
I wonder if an aftermarket thermostatic fan control module could be adapted to turn your water pump on and off? Here's an example of the type of device I'm thinking of:
Intercooler water pump:
Wouldn´t the XJR ecu already have option to turn on the intercooler water pump as there is one in the XJR intercooler also or is it directly temperature controlled in XJR?
I have used that type of Thermostatic control switch's with varying results. The schematic can be used to either control the low side ground or power of the fan or pump relay. The switch itself is not sealed for humidity or corrosion, Hence I seem to to have to swing the dial fully left and right and then put back in in it's marked spot. The water pump schematic shows that it is fused to ignition power, No control from ECM. I would think that you would want the pump operating at all times, But a fan for the intercooler would be operated by a thermostatic switch such as shown.
Intercooler water pump:
Wouldn´t the XJR ecu already have option to turn on the intercooler water pump as there is one in the XJR intercooler also or is it directly temperature controlled in XJR?
I believe the XJR pump runs whenever the ignition is on.
@greg21 Turbo noise coming soon! @Jagboi64 According to schematic posted by @AnttiM the SC water pump runs continuously with key on. I've got my water pump wired to the fog light switch but looking into other options.
Fabricated heatshield today. Not the way I pictured it in my mind last night, I was just unable to execute. It should still work but I may make another.
Used matte board to fabricate a mockup. Be sure to turn your pattern over before tracing and cutting the pattern; otherwise it will be backwards; ask me how I know!
Had to tack weld threaded bosses on the manifold. Would have been a lot easier out of the car. Wound up welding two additional bosses to sides of manifold to keep the heat shield from "singing" when manipulated.
Heat shield installed, hopefully it will have the desired effect reducing under hood temperatures.
Fabricated a mini "turbo blanket" from heat tape/wrap. I used my grommet press to punch a few grommets in it. I'm thinking about using long springs from hole to hole to secure it.
Last edited by bsparkman; 10-09-2020 at 07:48 PM.
Reason: Post and images appearing as html text only can I delete?
This is a truly very impressive piece of work. I congratulate you on your achievement.
I have a couple of suggestions if I may. I understand that you are already using the standard engine ECU from an XJR with standard injectors from an XJR. As mentioned elsewhere, the air meter from an XJR (LNA1620AA) has a different airflow against voltage characteristic curve (1024kg/hr max airflow). This is "hardcoded" into the ECU. I know because I have a full data listing for every variable in the calibration. If you use the air meter from the naturally aspirated engine (about 650kg/hr max), with and XJR ECU, it will overfuel the engine. The car will drive much better if you also use the airmeter from the XJR. Near max power the standard fuelling on the XJR is under 11:1 to keep the exhaust temperatures down. Your can afford to turn up the boost and saturate the airflow meter a bit. Once you flow more than 1018kg/hr, the ECU won't deliver any more fuel, so will just get less and less rich. If you want to go to even higher boost levels (ie when the fuelling "leans out" beyond about 12.5:1 ,I can provide you with a reprogrammed ECU. This is what I did for my Eaton M112 supercharger conversion.
Once again, I think you've done a brilliant job on your car.
The intercooler water pump on the XJR runs all of the time that the ignition is on. There is no advantage to having a more complicated strategy to turn the pump and on and off with boos pressure. The transient vehicle performance is best if you keep the water in the intercooler circuit cold all of the time.
@XJRengineer Andy, thanks for the kind words, coming from you that quite the compliment. Your are absolutely correct about my NA MAF sensor, as soon as I apply the slightest bit of throttle input AFR drops to 13.0 a little more throttle and I'm at 12.5, all this well before my turbo begins to spool. Those AFRs good for the air fuel density under boost but I'd like them to be a little leaner when not boosted to improve drivability. @Larry Louton and I are conspiring to swap out the NA MAF with his reman SC MAF from Fuel Injection Controls (FIC). I was going to swap it in tonight but discovered I lost the heater on one of my downstream O2 sensors (A) and the O2 sensor was outputting a continuous 5V. This condition causing my car to stay in open loop mode and no point testing the new SC MAF under those conditions. It's just a theory, but it appears the loss of one O2 heater affected the other downstream O2 sensor output according to my tests. It appears the upstream heater circuits and the downstream heater circuits are each wired separately in parallel, because the heater elements are wired in parallel, together they would measure half resistance of just one heater. Short or open one heater element and you've effectively changed the resistance for the remaining heater element. I'm guessing the difference in heater temp impacting sensor voltage output. I plugged in two new sensors and laid them across my vacuum booster, started the car and witnessed both heaters warm up and saw the voltage drop from 5V to around 3.7V I'll install two new sensors tomorrow and let you and Larry know how I made out.
As soon as a few irritants worked out and I've a solid baseline to work with let's talk more about your ECU modifications.
Thanks again for the kind words and sharing your institutional knowledge.
A company called Paramount turbocharged an X300 not long after they were released. I remember reading a road test by Car magazine, where they heaped great praise on the car for it's performance, while still keeping jaguar quality ride and handling.
Plato once stated, "Necessity is the mother of invention." Today, some might argue YouTube is the mother of invention but is it really? I'd argue there is no "invention" without "intention". The X300 chassis in the YouTube video appears to have an AJ6 motor; the same motor I had in my 1990 Sovereign. Fuel rail, intake manifold and the absence of coil on plug give it away... I do appreciate the raised areas in the hood above the turbo and that might be something I do when I disassemble and paint my car in the following weeks. It has been a couple years since I've rolled something out on my English wheel... The last time I used it was to fabricate the tank and fenders for this bike, "Dirty Donna", playfully named after my current wife. There were others; "Black Betty", "Crime Time", "The Wrath", "Son of Wrath" but only one named after my wife... Interestingly, I sold and shipped it to a gentleman from London. You'll note the oil cooler on the left side of the bike the same oil cooler I used on my jag for the PS fluid after the PS cavity on my radiator was breeched with antifreeze. Rather than abandoning my radiator, I cross-connected the PS fittings on the radiator tank (now contaminated with antifreeze) and ran the PS lines to the same cooler pictured below mounted in the Jag's grill opening.