Zray!
What it comes down to is "How much Money do you want to spend"! Avos has the knowledge and has spent the MONEY and has done the work to make our little Engines produce 650 or 750 HP with a Twin-Screw Blower.....No Doubt!! In addition he has sold several of those Units to our Friends here on the Forum and most of the Guys seem to be Happy with them....If I was a little younger...I might have bought one myself but so is life!. I'm old!

What some of the other Guys have done is take the Eaton, as that is what Jaguar gave us and try to make something from it....If you do everything right and spend a little money on Pulleys, Intercoolers, Water/Menthol Injection Systems and more powerful Intercooler Pumps and some Headwork, you could possibly approach 500 or even 525 HP but that's about it on the Little XKR Engine...(4.2 Liter's is only 156ci's) and that ain't much!....You will have to go for the Juice (Nitro) to push it on up any more! The Nitro set-up would probably cost you another $1,000.00 Bucks or so! The only other small Engine I ever had was the 2.4cc that I built for my 64 Bug! What it all comes down to is the Power to Weight ratio......and MONEY!.

GrandDad always said, "MONEY determines How FAST you can go!"

Billy Clyde @ Cinco Ranch (Texas)

 

ha ha. I’m getting up there too, 69 at last count. Still smart enough to know my reflexes are not getting any better. The stock XKR is quick and fast enough for my intended use and diminishing reflexes. My previous ride was as quick as the XKR but not as stable at speeds over 130 mph. I had the ‘66 Shelby GT350 with a vintage Paxton tuned pretty well for the technology of the day. I refused to modernize it out of respect for what the engineers of that time period were able to accomplish with little more than a slide rule to go by. I enjoyed the time machine aspect of it as well.

The 55 year old Shelby would cruise all day at 135 with no drop off of power as the supercharger heated up (external fluid cooler). But over 135 mph the handling was not confidence inspiring. Besides, my clutch leg is giving out, (too many motorcycle accidents in the 1970’s) , hence the search for a fun replacement; enter the XK.

All’s well that ends well.

Z

 

Thanks for the advice. I have changed the air filter to K&N and replaced the intake tube with a Mina Gallery alu tube, thats it so far. The air filter sits in an aluminium box of my own design. Changing to a bigger MAF and throttle body will require a different ECU I guess? Since the 4.0 ECU is not programmable

 

thank is really nice looking !! You should be very happy with your work.


Z

 

The ProM units have a calibration for the AJ27 (4.0) engines (order it also as a AJ27 4.0 Jaguar), that the one I started myself with. For the TB the switching point that adjustments are needed is more around 86/87mm, so well above the 83mm offered here on the forum. For the 90mm I use adjustments are needed , which i did by altering the signal electronically a bit to stay just below the threshold for a DTC.

 

How far can you go with the stock ECU on the 4.0? Lets say with the mods I will have when I get the SC back on top of the engine with the 10% overdrive of the Eaton. I also have a full Milltek exhaust with only the rear silencers. What hp can I expect?

And if a bigger TB and a bigger MAF where added together with the ProM box, what jump in hp would be to hope for? For the same 4.0 with Eaton and 10% overdrive

 

Well, my ECU is still stock, except for the ignition is advanced by 3 degrees, that's it.

So far my experiments showed no added upper end power with exhaust updates, but these where quick tests, certainly not to be conclusive. The sport cats certainly dud make a difference.

I have only limited experience with the Eaton on my car, as I moved to another supercharger before further enhancements, so I can't give you actual numbers. Also, having a bigger intake pipe and filter but still 2 resections in there (MAF and TB) you don't get the maximum out of it.

If you could tell the intake vacuum at WOT around 6.000 rpm, I can give a rough estimate on what a MAF and TB can give.

Edit:
I just checked the website of what the 10% pulley should give, but can only see a text part, without any dyno proofs:
It is generally accepted that a 10% blower speed increase on these cars gives 2.5-3psi boost pressure rise and 35-40bhp (with 40ftlb) improvement on a 400bhp car. While that sort of figure is realistic for the midrange, high rpm peak power rise may be more like 10-15bhp, because the Eaton M112 becomes less efficient at the high end of its operating range. Dyno graphs for M112-equipped cars tend to show boost dropping off towards redline, but that doesn't prevent the trusty Eaton from responding beautifully across most of the rev range, giving the feel of a larger motor as well as more instant response.

Part of the drop off towards higher RPMs is also based on the vacuum you pull, so by ensuring you maximize the air delivery the less power drop you get. Assuming these figures are correct and based on a relative stock intake (so 75mm TB and MAF) then you could add another 20-25 HP towards the top, maybe more even, hard to tell without any vacuum numbers.

Then with good cooling, you will have a much nicer power curve, so less drop off.

That was one of the benefits with the TS, even with the numbers I have, the torque is a flat line, so you truly get the feeling the car wants to take off (until it shifts again).

 

Getting some pretty useful info here in this thread.

When upgrading my car one thing that was paramount was cleaning out the charge coolers as well as the crud below the TB.

I did all of this on a 100,000 mile engine and I would estimate that the charge coolers were better than 50% clogged maybe even 75% as the mess in the charge coolers is rather fine.

So that is why I installed an oil catch can as well as the water/meth system.

So I have done the following above and beyond the above:

10% pulley.
Ported SC
Upgraded rotors (from later model) slightly better gearing supposedly.
Ported and matched elbow to SC so smoothing out the flow a tad.
Stage 1 air intake but standard air filter with flap removed.
Range Rover intake. The inlet pipe going into the TB.
Replaced mid muffler with X pipe.
Upgraded Bosch SC pump.
Additional in line SC radiator. (from a Ford Lightening)
Twin 6" puller fans in front of that radiator.
And of course the Quaife.

Porting the SC was done when I sent the SC off to put the 10% pulley on and is the only work that I did not do myself.
The porting was probably a waste of time from everything I have read on here. Not the case with the Eaton on the 4.0 engine tho apparently.

I do not think there is anything significant that I could do now on top of what I have done. I do not have VVT unfortunately so even an ECU tune, if it were easily available now,
would not add that much with poor bang for the buck.

Its all documented in the "quest for 450hp" thread which is a very useful thread indeed.

 

Well... there is still something you can do, not significant but still (leaving bucks in the middle)...

So the additional ones still open are the TB and MAF as I see it. If you can get me also the Vacuum readings I could as well give an idea of what you could improve. One important area for improvement on the intake was indeed the RR one for your type of car, that is covered at least, but there is still some to gain in airflow with the MAF and TB to compliment it all.

 

The AJ27 4.0 doesn't have a vacuum sensor, right? Maybe I should add one now since everything is apart already

The part that benefits the most from porting should be the intake elbow? Right beneath the flange on the elbow where it connects to the TB it looks awkward in terms of air flow, with the elbow itself holding a lot more surface area in comparison to the flange area, and the sharp edge between the two areas. Thats where the porting is usually done?

 

What do I do to get the vacuum readings? Would Torque Pro give that?

So my existing MAF could be improved?

What would your estimate in extra hp be with a better MAF and larger TB be?

 

Only the ROW 2000 MY cars, from 2001 they do have the vacuum sensor, and the NA (North American) cars have it already from the 2000 my.
You have here benefit, as from the use of the vacuum sensor the ECU has (somehow hardcoded) the famous EGR measurement on vacuum to check if the EGR is working. So you have the option to blank it off here, but you need to have the EGR connected. I have the EGR electronically connected not not attached anymore to the intake elbow.

Yes and some other parts, you want a smooth area to avoid air turbulence, and the more bends you have or uneven areas the less flow in the end. There is more to it of course, but try to look at pictures on the web with fluid dynamics pictures on air flow, imagine how particles at high speed are pushed to in corners. You also don't want empty pockets, as that will cause turbulence as well, or will slow down the particles. This is also why its better to have a one size intake (certainly not small somewhere and the larger again, from large to smaller is good), as that will cause an acceleration at the smaller areas and a deceleration again at the larger diameter parts, in total it will loose its speed. Hence the larger MAF would be good to have.

 

Yes, your car has a good vacuum meter, and any odb device can read that info. However odb devices can only get about 6 sensor figures per second, so always select only 1 sensor you want to monitor (or at max 2, like RPM), and do a run at a high gear so you get more readings per second. A 2nd gear is to short, so you miss readings and never get a precise measurement at top speed. So at minimum I would use 3rd gear, and also put it in 3rd gear so you don't get an early shift.
Please be careful, as 3rd gear on the public road could be illegal, so only do it then on your driveway ;-)
(The IDS/ Jaguar tool gets data via the CAN bus and also at a higher priority that what the ECU sends to the odb port, at least double the amount of data points per second).

Yes indeed, the Prom units can be used, they have a calibration for the 4.2 engines.

It remains difficult to say, if I have more data at max rpm. so boost pressure, vacuum reading and maybe also the MAF reading, I could give a better estimate. I would guess it could be the same order of magnitude as the XKR, but these are different setups.

 

That's what I thought, since I haven't seen any sensor in the intake elbow on my 2000 year model. Originally sold in Italy so that's to be expected then. If I add a sensor, where should it be located? The elbow is quite crowded around it with all the vacuum piping, coolant piping and EGR.

When it comes to EGR, have you removed it? If so, do you count on water/meth spray to lower the combustion temperatures instead of what the EGR should have contributed with?

 

The EGR is lowering the combustion temps at driving within closed loop, once you put load on the engine you enter open loop and the EGR will be closed which can't then control the combustion heat anymore. In these EGR (/closed loop) areas I don't do anything, other then for me its more to keep the intercoolers clean, as the oil vapors and exhaust gasses/heat will put a sooty layer on the intake.
The water/meth only starts under boost, so way outside of closed loop/EGR operation, and there it is supporting keeping the internals clean and lower the intake temps.

You should have stock a rubber hose that is closed at the end (this is where the NA and 2001+ cars have the vacuum meter) so that's the tubing that is attached to the intake (RH side), and black vacuum valve controls the supercharger bypass. That is where you can get the vacuum reading.

 

Lots of good info here, Avos, really appreciate it

Been checking out the MAF units available from Pro M at their website Pro-M Racing Mass Air Meters

Cannot find any units specified as compatible with any Jaguar, though. Do you know which MAF in their current range that will play along with the AJ27 SC?

 

They indeed haven't it listed separately, but they do know what to do if you order it with the description.
You can use the standard 3.5" tube, or the 92m one, all great quality units. Don't forget to buy the pigtail as well.
When ordering you don't need to provide any info of the current injector sizes, only when you change yours, as then they can calibrate it for that.

 

ok, great! Did you use this in combination with their control hardware/software? Is that recommended? So that the MAF signal can be used by the ECU. My AJ27 ECU cannot use the signal from the Pro M MAF I guess

 

If you order it with the AJ27 4.0 Jaguar, they have the right calibration for you car (no need for any signal adjusters).
The only thing that doesn't work is there thermistor for the temperature reading from ProM. You could either use that one from your original MAF or buy a used coolant or IAT#2 temp sensor from 2002 and younger XK8/XJ8 as are the same.
Here is the wiring diagram, just check your electrical diagram and you will know what to connect.

 

The scenario you described here Avos, is that assuming the Universal Hot Rod Engine Management System? When ordering this component I see that you need to specify your car and engine

Pro-M EFI Universal Hot Rod Engine Management System (promracing.com)