I did write an article for the Jaguar Enthusiasts Club magazine some time ago about improving engine performance and it did include pictures of my carnival red car with the M112 converion.

I maintained the pulley position wityh my M112 instalaltion and allowed that to dictate the position of the body of the supercharger. I had to tilt the inlet manifold to fit the back end of the M112 unit underneath it. i tilted the inlet manifold by fitting a wedge shaped plate between the inlet manifold flange and the cylinder head.

 

Any way to get a hold of that article? Eager to learn more about the x300 XJR.

 

go to Manufacturer of Supercharger kits, remanufactured superchargers and supplier of supercharger oil.
if you click around youll find many blueprint specs on the diff models and might help to call and talk to them too since theyre a rebuilder of stock units and hiperf as well.
I linked the mp112

 

Seeing as how I will have one donor M90 and I have two available M112s I am going to try and swap nose sections, not that it would be a big deal to swap them back. If it works out the way I have it planned out in my head (fingers crossed) I will be able to have the M112 located far enough forward that the body of it doesn't have interference issues with the heat exchanger and so forth. I am definitely interested in discussing more in depth your ECM tunings and exhaust manifolds. I will leave it up to popular opinion if it stays in the public forum or if we should move it to private messages. I don't want to clutter up the forum with posts that no one else is interested in.

 

+1 for public please

 

Absolutely PUBLIC please.

Always interested in a project.

 

I can reprogramme the Engine ECU. So far I've changed the base ignition map, idle ignition maps in neutral and drive and the open loop fuelling calibration. But with over 600 constants and several hundred maps to choose from there is plenty of opportunity for making changes. The key is knowing what to change and by how much.

As an example, if an Eaton M112 supercharger is fitted to an XJR6 then at wide open throttle above 4000rpm, then the airflow into the engine will exceed the upper limit which can be measured by the air flow meter (AFM). The effect will be to pump more air into the engine but without injecting a corresponding increased amount of fuel. The engine will not run sufficiently rich to produce maximum airflow and the combustion chambers will get very hot. This will lead to knock/detonation/pinking or even pre-ignition and engine failure. Reprogramming the engine ECU could allow the fuelling to be artificially enriched in order to offset the under-reading of the AFM.

As another example, an ECU could be reprogrammed if the owner converts his car from automatic to manual. This will prevent the ECU going into a default mode that applies 5 degrres of retard when it detects that the automatic gearbox ECU is no longer present.

As another example I have increased the ignition timing on my car under all conditions where the engine is knock limited to take advantage of running it on 99RON fuel (approx 94 pump octane). This is more sophisticated than my bracket because I can vary the amount extra ignition advance. The software determines the ignition timing from a table containing 16 rows and 16 columns of data which correspond to different engine speeds and airflow/rev.

These are just a few examples of what is possible when reprogramming the engine ECU.

 

My article on Improving Engine Performance was in the September 2010 issue of Jaguar Enthusiast magazine. Back issues are available from the JEC office in Bristol, UK.

 

XJRengineer,
The car is very shortly going for the body resto, the r/r 1/4 needs to be replaced, some dings and dents fixed and re-painted. When it comes out of body/paint and I do the remainder of the mechanical modifications I'd like to coordinate up with you and map out the best ECM tune possible for the mods done to it. I have a 2.88 LSD out of a late 70's XJS I am planning on installing at some point. I have a good Salisbury case out of a 97 XK and the XJS LSD/ring gear and pinion. I'm hoping I can put the two together and make one that fits.

 

Realm, where the hell are you located, I have a NEW diff with power loc and 3.55(or 3.50 I dont remember exactly)) sitting in a jag box in the garage. I had looked up the part number and it fits(if I remember) a little earlier XJ than ours, but I always wanted to check and see what was needed to install. (swap out axles stub shafts, or carrier bolts and yoke....
But as with anything else I have too many projects and just ordered 4.56 gears for my 05 Nissan front and rear so Ill be busy with that in another weeks again
I cant give it away, but let me know if your interested in pursueing more info...

 

Realm,
The std final drive is 3.27:1 or 3.31:1 depending on supplier (I think it was dual sourced). So if you fit a 2.88:1 it will be much higher geared (I thinkl the v12 X300 (X305) had this ratio). Good for fuel economy but not performance. If you fit the unit from the 4litre NA X300 which I think was actually 3.53:1 (like the one Brutal is offering) the the gearing will be lower than std. It all depned swhat you want to achieve. Then there is the issue of whether you want to make it LSD.

 

Yes, I was in fact looking for off the line performance over fuel economy or top end and wanting to upgrade to limited slip. I doubt I will find much occasion to do 155mph so I wasn't too worried about it. I was mistaken about it's current final drive then, oops! We took the 01 XJR to the strip and were running high 13's with it (very poor traction, btw). I was trying to get somewhere in the 13's with the 95, if I can. I am definitly interested in the diff, Brutal. I am in the metro Detroit area.

 

part number is jlm162401

 

With a 3.53:1 final drive unit, 4th (0.75:1 ratio) in an auto XJR would give about 27.9mph/1000rpm. This equate to 140mph at the peak power engine speed of 5000rpm. My guess is that the car would actually exceed this speed, but probably wouldn't go all the way up to 166mph, when the rev limiter would be reached at 5,950rpm

 

Ok, so I had our parts guy pull up the X300 parts catalog and I couldn't find JLM162401, so I'm wondering if it's maybe a legacy part? Is there a ratio or color label on it anywhere, Brutal? I did find JLM11878 is a Power-Loc 4.09 ratio (blue/black cross label). How can I say this correctly... THAT WOULD BE AWESOME!! Any idea on what that could have possibly came in, Engineer?? It seemed to be a regular production part and still had availability in an exchange unit (it was somewhere around $1500 my cost). I'm just trying to wrap my mind around what 300 that Jaguar could have possibly put that ratio in. There were probably half a dozen different ratios in the catalog, Power-Loc and open.

 

HEADS UP!

There is a complete getrag 5 speed setup for sale.

Well ok, it's the whole car ... it is in the private for sale classified section. See the recently posted XJS for sale ad. Apparently 1 of 25 engineering samples brought to the US.

 

Any updates?

 

Unfortunately nothing new to report, been out of town, car has been put back in storage until I get some extra time and money. I have been refurbishing an X-Type for my girlfriend, working on my friend's sons '70 Swinger 340 and have the powertrain out of my Shelby Lancer still. Gonna be a busy summer, friends! My next steps on the XJR are actually probably going to be cosmetic anyhow. It's kind of a win/win to get it to my body and paint guy, it's out of my way and he can take his time with it.

 

You mention selling one of your 112s. Is it a jag STR top outlet 112? If so PM me a price if it's still for sale and in serviceable condition.

BTW a 50 and even 75 shot works well spraying pre blower. I have only sprayed a 50 wet so far on the STR because I am concerned about getting even distribution but after talking with the gurus at NX I am thinking about stepping up to a 75. Also the 50 is seeing about 75 rwhp on my car with the cooling and compression effect.

 

Anybody knows what happen with the NOS project in this thread? Or has anyone done NOS or Meth/Water to an xjr6?