So Brutal, with your logic, if I only get 40 rwhp for the $1,000 I spend and then I spend another $250 running it on the dyno just to prove it, it will reduce the power gained per $$ spent ratio considerably. Sounds like voodoo economics to me and either I will be happy or unhappy no matter what the numbers say. Kinda like Russian roulette...there's no second guessing if you're wrong .

 

Yep kyanite, but i dont count the dyno costs as a modification no more than gas to get there or the shop. And where do you go for $250? Most ive been on are $75-100for 3 pulls. And I have always been THAT GUY that wanted to do my own testing and publish the results either good or not so...
On another note i love to see all the interest and companies stepping up and offering becasue people are finally buying. It wasnt that long ago about the only companies that did much with jaguars were only in the uk

 

I'm in So Cal and it's $125 for each session of 3 pulls. So $250 total. Maybe I can take up a collection from the group to fund the before or after - worth $125 to me to do that, not $250 ;-)

I, along with some others are the "next generation" of owners and we are buying to keep them and have fun with them, not just leasing a nice car that we're afraid to modify. And with the R and R-S models, Jaguar is finally becoming more of a mainstream performance car with a very high level of competence, so more people are willing to mod them to have a car that can perform like or even outperform an E63 or M5, but aren't so common.

 

Ok, I'll add more text later. Dropped the 2011 XFR off for pulley and tune. I assumed they were going to dyno. I got back later and asked about the initial pull and it became clear that we had miscommunicated. So, our baseline is car with pulley & stock tune. Then pulley with tune. I asked for flywheel numbers and he put both.

 

Glad you made it over there on your day off. I know you haven't had enough time to have the ecu fully adjust, but how does it feel? And I thought EuroCharged only sold the 1.5lb. pulley? The charts say 2.5lb pulley.

 

Haven't had much time to drive it yet, definite change. Power is immediate and directly related to the pedal. You don't 'gunn it' or 'punch it' to accelerate then back off. There is no time to back off.

Can't answer the question on pulley boost. I know that is what Jerry typed on the chart. There was no discussion about a 1.5 vs 2.5 As to AFR he said the factory map is 'pig rich' and they leave it that way and don't lean it out.

More reports once I'm able to stretch it out..

 

Hi!
The XFR mods on my car currently is remap, pulley and full exhaust including sport cat's and the dyno reading is more or less the same as your posting. I have attached my dyno run following a slight tweek in the mapping early this year by the same tunner even though I had the mods since March 2010. The dyno run was immediatly following the new software, so I assume additional 10whp following caliberation.

 

yeah it does show 2.5 pulley and why did they show stock in wheel hp then post everything else in crank???? That does not show apples to apples. But still great improvement
yes thats a very fat AFR and could change to a point higher. but hey lean is a killer, rich is not. but still a 11-11.5 afr is still very safe. 10-10.5 is just pure glutonous

 

Nevermind the post. Was on the mobile app and it doesn't show attachments.

 

Brutal, do you have any thoughts on why the afr on the xkr and xfr tunes would be that different? Could it be the different dynos/locations? I'm going to call Jerry and see if he can give me any better info. I wonder if that's the difference between the Stage 1 and 2 tunes?

 

Jerry told me he was going to show both rwhp and flywheel of the initial pull just so I could see the difference in methodology. It is running great. I'm glad I have big brakes . Hopefully the Mina exhaust will arrive soon. Then I will do another pull to see if there is hp gain or just better sound.

 

Congrats, and those look like good improvements. I'm curious about the pronounced loss in torque from ~3000-4600 rpm after the tune, and hopefully jerry can shed some light on that. This is the area where the factory Transmission Control Unit "limiters" pulls power even at stock power levels to prolong transmission life. I had thought the ET tune might have removed the limiters, but this shows that at least something is holding back power in this area. I recall hearing that there are only 1.5lb pulleys for the Jag, even though some are promoted as 2.5. Curious if this is true, and also why the overly rich AFR at higher rpm wasn't leaned out a bit...that's usually where the tuning process starts.

Bruce

 

I did email Jerry about the dip and the other questions you had. Here is his response.

We keep the AFR stock so that is why it’s running so rich. There is for sure more power to be had by leaning out the mixture, but at what cost? You know?

The dip in torque is most likely belt slip and not a limiter since we remove them….as you can see from the XKRS graph.

The graph he is referring to is Matt's which I have attached.

 

Looks more like a torque limiter to me, certainly no belt slip.


Very easy to check though with the dealer tool, just look at the throttle opening.

 

+1

 

Jerry,

Perhaps installing an XKR-S flash with torque limiters removed on a XKR isn't fully compatible with its tranny control unit or other electronics and sensors. Have you data-logged the ECU during a dyno or street pull to see whether boost has been increased 1.5 psi throughout the rpm band, or being bled off in the midrange to limit torque.

"at what cost" doesn't really answer the rich air/fuel ratio question (~above 4000 rpm). Are the gains you show above that from the extra boost only, or are they also from advanced ignition mapping? If they are from the latter I would ask why you didn't adjust the AFR to say 11.5 or 12.0:1 first and then adjust the ignition map to end up with the same safe power. And if you decided to gain power through ignition map only, how did you did determine "at what cost" with that strategy?

How did you determine how much advance you could safely add, or did you just add a little across the board because you were specifying 91 octane (or 93 in Matt's case).

Tuning that I've been involved in use monitoring of knock and torque as the fuel and ignition maps are being adjusted. The tuner would first adjust fuel across all load and rpm cells no richer than 11.0-11.5:1, and closer to 12.0:1 for fuel economy, power and other benefits, and tuned at partial throttle as well as full. Then he'd start adjusting the ignition map, advancing timing until knock is detected, or torque stops increasing, and then back it off slightly to provide the desired safety margin. This procedure is how the tuner knows that he's safely optimized the power, fuel economy, and throttle response for the grade of gas he's tuned for. He can also do a second tune for race gas with some ECUs that allow user switching between tunes.

The custom tuning procedure I outlined is done for a specific engine, and not necessarily ideal if used on and identical engine that may operate slightly differently. Your tunes are provided by others I think, and you may then tweak them for your particular applications. I wonder if you could explain a little about the degree to which the original tunes are prepared and optimized, and how you customize them for a particular install. Since no monitoring is done when the tune is installed, I imagine the tune has to be done extremely conservatively to allow for variables from one engine to another and make it safe for the worst case.

And finally, can you provide more of a custom tuning/monitoring service for tunes installed in your shop as I outlined above at extra cost?

Thank you, and I hope a clear understanding of your tunes will attract many satisfied Jaguar owners.

Bruce

 

I'm glad someone said it. Fuel trims are usually one of the major components that good tuners will adjust to maximize power. You absolutely can adjust stock fuel maps and still have them well within safety margins. In fact, a custom tune is recommended for some of the stock turbo Subarus because of the awful and in some cases dangerous stock mapping.

I have had off the shelf (OTS) tunes on several vehicles and custom dyno tunes on several others (Phil @ Element Tuning flew out to MD to tune my old 2.8L STi) and although the OTS tunes were good the custom tunes were always far superior and the cars performed much better. I am wondering if anyone will emerge to do truly custom in-car dyno tunes for Jaguars.

 

Interesting.

Good to have members on the forum that know about this stuff.

 

Well.. I'm not Jerry. I was just posting information from the email he sent me.

I get it, the Eurocharge tune is not customer specific. I think many are interested in Eurocharge because they have an ECU tune that generates significant HP gains for half what ETG is charging. Keeping the 'pig rich' factory AFR means (I'm guessing) they can safely send this ECU tune to customers where ever they are located.

I think I got out the door with tax for $1100, pulley installed, with dyno runs and have +55hp at the rear wheel. I'm happy. Would 600hp be better than 575hp? Yes, but "at what cost"

 

I'd point out that an engine is more prone to pre-ignition (aka knock or detonation) closer to the rpm where peak torque is seen on the dyno, and less likely at higher rpm. Your dyno indicates to me that your tune is more aggressive in the area that you need to use the most caution, yet less aggressive in the area that is less prone to cause engine damage. That leads to my wanting to establish how the tune installed on your car and Matt's was created and tested, and not to why they don't make more power at high rpm.

I don't think the dip in torque in the sensitive rpm area is wheel slip either, but either the ECU protecting the engine by reducing power by responding to a knock sensor input by retarding timing, or a limiter responding, or simply inconsistency in the tune across the powerband.

I'm sure Jerry will provide an explanation for what we're seeing, and make a strong case for the quality of his tune.

Bruce