Dear All,
Contrary to my previous post it now appears that crank sensor bracket EBC1253 was fitted from 3.6L engine number 108835 to 4.0L engine number 161586. I can therefore provide a revised version of this bracket with an extra 5 degrees of ignition advance to any of these cars. Crank sensor bracket EBC5017 was fitted to all 4.0L and 3.2L AJ6 engines after 161587 and to all AJ16 engines. I can also provide a revised version of this bracket with an extra 5 degrees of ignition advance. I currently have stock of both designs of revised bracket, if anyone is interested.

 

I've got just 4 brackets left that replace EBC5017, until the next batch arrives, if anyone wants one.

 

Hi Andy

Just fitted the bracket today. I also adjusted my throttle cable which was getting a bit slack. Conclusion : Feels like a different car completely. Superb.

Just to confirm, my 1990 US Spec 4.0 Sovereign had engine number 101903. The bracket was part number EBC1253 and your bracket fitted perfectly.

 

Hi Sarc,
Thanks for the very positive feedback on my replacement brackets for EBC1253.


Dear All,
I have just taken delivery of another batch of 20 replacement brackets for EBC5017. This is the part fitted to all 3.2L & 4.0L AJ6 engines after engine number 161586 and two every AJ16 engine.


If you want to treat yourself to e bit more performance and fuel economy for Christmas, then please get in touch (helenstodart@gmail.com)

 

After reading about this upgrade and finally pulling the trigger, I received my bracket last night. Installing it was ridiculously easy. In fact, I didn't have to remove the fans or the upper radiator hose to access it.

I definitely feel a difference, I left the battery disconnected for 30 minutes before the install to reset all that I could. I notice that it idles smoother? I also have noticed smoother shifting. I have only driven a few miles so far and not under all conditions yet. I would say the best word to describe it so far is...velvety. I am hoping to feel more as I drive more and the computer adapts.

I am not blown away, but see the benefits and will be closely watching the MPG's as that was a major reason for doing this upgrade. Stay tuned for more reporting.

 

UPDATE:

The engine idles smoother and makes the cabin more comfortable. The car comes alive as you get on the gas in direction proportion to application of pedal to metal.

Fuel mileage is up (+1.5ish?), however, I haven't driven longer distances to see the increases on a longer haul.

I am definitely glad I did this modification. It is the missing link on this car, it takes it from a big car, to a quick, big car (I'm XJ6L).

I just need to figure out a cold air intake and turn to exhaust issues.

 

Well, I had been working on my stereo and had removed the "Sport/Normal" button when I did the bracket install. I have since replaced the switch, THIS is a big difference with the bracket. The car really comes alive.

In addition, I made a custom air intake for under $50 for the Jag that really woke up the low RPM especially. I would say this, with the bracket are perfect as the bracket really helps on the higher revs I noticed and the larger amount of air from the intake upgrade helped the low end. For less than $175 the car is vastly improved.

Gas mileage is just above 19.1 on the computer and I was around 16-17 before.

 

SD96,

can you post a photo of your air intake?
thanks

 

Ok here it is. Simple parts from Home Depot plumbing aisle. I actually cut the stock pipe before the MAF sensor. The pipe I bought from HD fit snuggly over I have it duct taped right now just because I haven't replaced the rubber stabilizer mount yet. I will later silicone seal the piping just for good measure as well as use contact cement on the other fittings. They press fit so well, however, that I can't even get them apart. The filter is a Spectre I bought at my local Auto Zone. All in all it was under $45 I think? Cheap cheap cheap for a decent improvement especially when coupled with Andy's bracket. I will later make a heat shield as well as find ways to push more air up to the filter through the bumper, etc.

 

While I had the radiator out of our ’93 XJ40 a couple of years ago, I took photos of Andy Stodart’s timing advance CKPS bracket and the OE bracket to show how Andy’s bracket advances the timing 5 degrees. I'm finally getting around to posting the photos, which will supplement the ones posted by aholbro1 earlier in this thread. I also conducted "Before and After" performance tests, and those numbers are included here.

I installed Andy’s bracket in 2013 as part of a series of changes I made to our ’93, including a new O2 sensor, X300 fuel injectors, Andy’s CKPS bracket, then back to the original injectors after I had overhauled them. I wanted to test for any differences in fuel economy after each of these changes, so I mapped out a 60.0 mile test loop with only a few stop signs and lights. For more information on my test loop, see my upcoming post on fuel economy tests.

Our ’93 with the late AJ6 engine and higher-amp alternator has the same revised crank pulley as the AJ16 engine, so Andy’s bracket is a direct fit.

Prior to installing Andy’s bracket, I made five 0-60 mph runs. I ignored the slowest and fastest times to reduce the effects of my own human error while pressing the START and STOP buttons on the stopwatch. I averaged the middle three times.

Note that the XJ40 is OBDI, so unlike an X300 I couldn't use Torque Pro and my ELM327 bluetooth OBDII device to more precisely time my runs.

The average time to 60 with the OE CKPS bracket was 9.03333 seconds. Bear in mind that at the time of these tests this was a 20-year-old car that had done more than 180,000 miles. The average fuel economy over three separate runs on my 60.0 mile test loop was 23.659306 mpg.

After installing Andy’s bracket, subjectively speaking, the engine was more alive and responsive, especially at mid-range and higher revs. However, the average time to 60 was 9.02 seconds, an improvement of just 0.01333 seconds over the stock CKPS bracket. Note that in conducting these 0-60 runs I began with the engine at idle. In retrospect I think Andy's bracket would have probably produced a more significant result if I had begun each run with the engine revved to 1,500 or 2,000 rpm before releasing the brake to launch the run.

Of even greater interest is that the average fuel economy with Andy's bracket was 25.619129 mpg, an improvement of 1.959769 mpg. That's right, an improvement of nearly 2 miles per gallon! That makes Andy’s bracket one of the few performance mods that will truly pay for itself.

I would be curious the hear from anyone who has conducted similar tests on an AJ16 engine.


Here’s a close-up of the crankshaft position sensor (CKPS or CPS on earlier cars) on the stock bracket:





Here’s a comparison of the stock bracket (foreground), which is cast aluminum, and Andy’s revised bracket, which is precision-machined from billet aluminum:





The CKPS mounts to the bracket with one 8mm hex-head screw, and the bracket mounts to the timing cover with two 10mm hex-head screws:





The position of the CKPS is critical, so the bracket is precisely located by two hollow dowel pins or locating sleeves through which the mounting screws pass. Note that in the photo one of the dowel pins remains in the timing cover:





Take care not to lose the hollow dowel pins/locating sleeves, which may remain in the timing cover or bracket, or may fall and roll into that pile of sawdust you’ve been meaning to dispose of:





The photos below show how Andy’s bracket positions the CKPS 5 degrees earlier in the clock-wise rotation of the crankshaft. The teeth on the crankshaft timing ring gear serve as the reluctor for the sensor. Note the gap in the gear at the right edge of the top photo, which identifies TDC for Cylinders 1 and 6 during one complete engine cycle (two crankshaft revolutions). The ECM uses the gap as a crank position reference:




Cheers,

Don

 

Hi Don,
Thanks for taking the trouble to provide such detailed feedback on your experience of fitting my bracket. I was disappointed to read that you weren't able to measure a more significant reduction in 0-60mph time given your comment about the subjective feel. However, it can be quite difficult to produce accurate back to back comparisons in vehicle performance. Many factors can create significant differences in tests that were intended to provide back to back comparisons. For instance, testing a vehicle with a full tank of fuel or a near empty tank would change the kerb weight of the vehicle by 3%. Conducting the tests on different days when the ambient temperature varied by 10degC would change the air temperature and hence engine power output by over 3%. The under-bonnet temperature will vary for a given ambient temperature depending on how the vehicle has been driven prior to each performance test. This can also affect the temperature of the air entering the engine.


I hope that you find the increase in performance after fitting my bracket is noticeable, even if you haven't been able to measure an improvement.

 

Hi Andy,

First of all, I am positive that the subjective improvement in engine responsiveness due to your bracket is real and not imaginary, so I have no complaints whatsoever. And 0-60 mph tests are not only difficult to conduct consistently, they are only one indicator of performance. Since Jag saloons are not designed to be drag racers, a more meaningful test might be something like 50-70 mph for overtaking/passing, but such a test is beyond my technological capability on an OBDI car.

As far as my 0-60mph tests are concerned, I did what I could to eliminate as many variables as possible. All 10 runs were conducted within the same 30 minute period on a stretch of straight road about 2 minutes from my home. The primary difference in the car for the later tests versus the earlier tests was the small amount of fuel that was burned for each test.

I should have mentioned the other conditions of the test: The fuel tank was nearly full when I started the tests because I had just returned from one of my fuel economy tests and had topped up the tank to calculate how much fuel I had used. I left the A/C on, the radio on, and the headlights on, transmission in Sport mode, and had just checked the air pressure in the tires because that is how I conducted my fuel economy comparisons. I'm sure I could have run faster 0-60 tests with the A/C off, less fuel in the tank and revving the engine before releasing the brake to start each run at higher revs. My goal was to achieve the most Apples-to-Apples comparison I could, not necessarily the ultimate fastest 0-60 times possible. I probably could have dramatically improved the times by removing the J-gate trim so I could "manually" shift the gears and hold 1st as long as possible. Note that changing the CKPS bracket on a hot engine is not something you want to normally attempt!

The other thing to keep in mind is that this car is a N/A XJ40 that had more than 180K miles on the clock. It has the stock GKN 3.58:1 diff and ZF 4HP24 electronic gearbox. And while I wasn't able to show a significant improvement in 0-60 time with your bracket, the car is a lot more fun to drive, and I am THRILLED with the 2 mpg improvement in fuel economy over my test loop, which itself is designed for consistency of comparisons rather than ultimate best possible fuel economy (for example, the elevation changes 439 feet over the course - a flatter course would provide better overall economy in the tests).

I will be anxious to hear from members with X300s, and especially XJRs, if they are able to conduct similar tests, as my tests may not be representative of the results achievable on the AJ16.

Thanks again for making this terrific mod available to us!

Yours in appreciation,

Don

 

This is a review on YouTube, where they show a dyno run and state a 12HP rear wheel increase. If accurate and estimating losses through the drive train that is an increase close to 15-20HP at the engine. That brings it within "striking distance" of the HP ratings of the X308, and may even then exceed the torque of the V8 after doing the math if I recall.


.

 

Got mine today (thanks) - it's a well-engineered piece of kit. Got some time off next week, and hopefully some fine weather, to fit it. Will report back.

 

well my Andy-bracket plus a K&N pod filter shaved a second off 0-100km/h time in my 3.2 (10 s down to 9s)

what it doesnt do is improve low torque which is the weakness of the 3.2
the 3.2, once in the revs, gets along just fine. it's the 0-50 k bit that it suffers with.

This week I get delivery of my manual X300 XJR with 340 bhp. The previous owner has done 0-100km/h in 5.2 secs. The ECU was re-programmed by Andy. looking forward to it

 

I know what you mean about the torque, it's a lot of car to shift especially because the autobox tries to keep revs down - I've found it best to make use of "2" on the 'box and get the revs up when I need to crack on

Is the inlet really restrictive enough for a cone filter to make a difference, or would it only help combined with cold air feed in hot engine bay conditions ? I like the quietness of inlet and exhaust, though a hint of "beast" would be OK

 

Andy I think my car is a bit more responsive due to your bracket. If I took it off and drove the car I'd bet Id notice more difference than after putting it on. Unfortunately that always seems to be the case for these kinds of mods.

Now... I can't make your seminar. But I'd like to know how to really shave some time off this car's acceleration. Depending on the price... I'd pay for a dvd of your seminar. I'm sure a lot of guys here would as well.

Ive read about supercharger mods. But I've also read about gains in one area off the power band and losses in another. I suspect a motor rebuild and some machining along side the blower change is the better answer.

What ive noticed about the 97 xjr is 0-40 is not its strong point. Highway acceleration however takes newer sport saloons by surprise. The car is certainly capable of more than the us highway experience can offer. Certainly should make you concerned about the condition and speed rating of your tires.

It'd be nice to nudge the car down to a 0-60 of 5 or just under. The new jags I believe get a lot of that done with gearing. And I believe the performance reviews for the car stock are 6.5. So 5 is a long way.

edit: let me add that I recently I have noticed what I thought was failing suspension joints. I checked the pressure in my tires. They were at 35lbs. I think the service center did that last time. I bumped them back up to 50. Now, I have the wide / low profile tires on mine. So it may not make a big diff on a taller tire. But if you have the low pros... go chk your tire pressure.

Edit i say 50lbs... More like just over 47ish. I have HTRZ's i think side wall max is 51 cold.

 

Fitted my bracket just now - took 20 mins including rooting out 8 & 10mm sockets, cleaning the area (before and after removal of original bracket) and cleaning the sensor.
The sensor was a tight fit in the new bracket, took a bit of twisting/pushing to get it to seat (better than being loose, this is a precision made bracket after all). Probably easier with sensor unclipped so you can attach it outside the engine bay
Made sure it fired up, and will pop out for a bit of a drive after my lunch...

...(Post lunch edit) - Well, as others have noted, the engine feels more responsive and definitely more eager to accelerate, and at the higher revs I'm sure there is a bit more of a "Jaguar growl" . The gearchange is more noticeable now too, and the car feels lighter.
Sat at 70 with cruise control on, the computer reckons it's using less fuel and my average was up slightly (included a fair bit of town driving) which bodes well. 3.2 so every little helps, it's certainly improved driveability.

 

Hello Andy
Is this email still current?
I have emailed you twice as I am interested in purchasing one of these brackets for my x300 sovereign.
Can someone please advise where I can purchase one from?
Cheers Ryan

 

Here you go man! Helen Stodart helenstodart@gmail.com