I just reread my post and I really really really don't want to sound like I am bashing on exhausts. I would just like to see some numbers.

 

Xk 4.2
14.4 to 13.7 with a increase of 5mph (track timed)

The 4.2 n/a comes with 4-2-1 manifold (unsure what 5l have) and flow significantly quite well so yes they do in fact have a scavenging effect

Free flowing cats + dynamic crossover pipe makes up the rest of the mods to my vehicle (obviously tune to suit)

I'm yet to see how much a difference the enlarged throttle and shorter diff ratio make on my times *

In regards to Aston martins a lot of the vantage go the 100 cell cats and absolutely love the enhanced sound (I recall seeing a dyno chart were 9whp was gained on the 4.3 with only that mod)

 

This is exactly the kind of thing I wanted to hear. You picked up seven tenths of a second? Even up in the 14s where it is easier to pull tenths, I'm quite impressed. And the 5mph is enormous too. Interesting. What was the cost of your exhaust? And does anyone have any data regarding the manifold setup on a 5.0 as opposed to 4.2?

 

I suspect that majority of gains is in the tune , I really doubt of any noticable gains on the 4.2 car with exhaust mods..

 

I thought I'd take a moment and outline the actual costs so far regarding the tune.

In this case, AlexJag charged me $650 for the tune itself, and then another $650 deposit to cover the equipment that he mailed to me. The deposit will be returned upon the intact return of his equipment.

I have an iPhone, and have always used DashCommand to pull information from the ECU. When we were pulling data for this tune, some of the data just seemed really odd. Like DashCommand thought the the car was commanding 14.8:1 AFR during wide open throttle, which is of course ridiculously lean. Alex asked if I could switch over to Torque Pro and a related app called Realtime Charts, but those are only available on android. I luckily have a couple android phones laying around since I do mobile development work but I am going to add $100 for a cheap android since me having one already was a lucky circumstance. For what it's worth, the numbers that came out of Torque Pro made much more sense. I also bought a new OBD bluetooth dongle in order to eliminate that as a possible problem. $20 on amazon. The two apps were $6 and $3.

I discovered that my old school manual charger that was made back in the 70s was likely not adequate to keep the car systems alive during a prolonged session with the tuning hardware, so I had to invest in a new 50 Amp maintainer. $160 from Amazon.

I have so far run one dyno pull. The results are more than a little screwy since the car kept trying to shift and was throwing every kind of sensor warning you can imagine as the front wheels were not moving but the back was... but as long as I can run two pulls under similar circumstances all I really care about is the difference measured between the two, not the results it printed out. $75 so far and there will be an additional $75 afterwards.

Ran the car down the 1/4. Will do so again. $15 each outing. I will not include the cost of hamburgers and sweet tea although I think everyone would agree this is a valid expense.

I'll have to ship the equipment either back to Alex or on to the next customer. I'll assume that's in the $20 range.

So unless I've forgotten anything:

$650 - Tune
$100 - Android device
$ 20 - OBD device
$ 9 - Software
$160 - Battery Maintainer
$150 - Dyno
$ 30 - Drag strip
$ 20 - Shipping
=============
$1,139 So far

 

Tune is in! Will give first impressions in a bit.

 

waiting!

wj

 

OK. First impressions.

Apparently the Springfield PD has been monitoring my activities and decided to make it as difficult as possible to run the car. No joke, no exaggeration I literally got hit with radar IN MY DRIVEWAY. So I had to drive around a bit and hit the car wash.

The first thing I noticed is that the exhaust seems throatier at low RPMs. This isn't something I expected and I thought it might just be in my head since my senses were on full alert but by the end of the drive I am convinced: The car is perceptively louder, really only quieting down when the car is cruising. And I want to be clear that I mean louder in a very pleasant way, not obnoxious at all.

Secondly, and this could be entirely my perception and not based in reality at all, but the first inch of travel of the pedal seems to produce acceleration that is smoothed out. It's like before I had to push so far before any movement happened, and now it ramps in instead of just starting. This is difficult to explain and possibly not even real. But at "creeping along" speeds it's smoother.

Thirdly: Three words. Mid. Range. Torque. At anything less than full throttle there is a noticeable torque increase which manifests itself both as more push above about 3,000 RPM and more "umf" during those times when you are in one gear and haven't quite given it enough throttle to downshift. When you do get enough into the pedal to force a downshift the result is markedly more dramatic than before. Accelration through the whole range (at less than full throttle) seems improved but noticed the most about about 3,000 RPM. Please understand that this is ENTIRELY butt-dyno results but it certainly feels stronger.

Full throttle is something I can't really speak to, yet. That's the area where things like dyno pulls and 1/4 passes are going to show changes. It seems like it might be better? I drive the car at less than full throttle much more often than ***** to the wall so it makes sense that I'm noticing improvements.

Big question: Do the changes seem positive and noticeable? Yes. Second big question: Does the cost seem worth the results? So far absolutely.

I will be pulling data through Torque Pro later this evening and comparing it to the other data sets I pulled in the past few days. I will not give out specific data about the exact changes since that is the end result of AlexJag's work and it would be giving away elements of his work, but I will report back in a generalized way any changes that I see.

Going back out again. Will report later.

 

Allow me to amend my previous post. The torque (push) increase seems to be from 2500 rpm and up, as opposed to 3000. Also more than once I’ve been surprised by what seems like even more push at 5000 rpm.

 

A few more things that I have noticed: Shifts seem to be softer, perhaps a bit more drawn out. I'm used to that old school "torque converter" style shift between first and second, and 3rd on up is still rapid fire and crisp if you are essentially cruising, but get substantially into the pedal and the shifts are just softer. Hard to explain it, but it's there. Also it seems like the transmission is holding onto each gear a bit longer than I am used to. I ran this past Alex and he confirmed that this isn't just in my head.

I've also noticed that there's less snapping and popping when I manually downshift into 2nd. I'm going to assume it's because things are a bit leaner? I do have to admit to kind of missing that.

All in all, though, with NO hard data in aside from me looking at the data that the car is delivering, I'd call this a 10/10. Would repeat.


Edited to add: I plan on hitting the Dyno again this coming week, will post before and after information at that time. Weather willing I will be at the local drag strip Friday night (the 24th) and we'll see what transpires there.

 

Great news, it sounds as if Alex's tune has also made a difference to your TCM, or else reset it to relearn the extra power of the tune

Without giving anything away could you ask him which one it is?

 

Did you drive the car much with it in Sport mode both from the Flag button and the transmission S mode? I only ask as this is exactly the way it goes when you engage the S mode in the shifter, more aggressive transmission shifts, holds them higher into the rev, doesn't go into overdrive at highway speed, etc.

The throttle response difference reminds me of the Sprint Booster, it "enhances" the throttle response. I find the Flag button does that for you also.

Great feedback on the torque and performance increase, sounds like it was well worth the effort!

 

"Did a good amount of changes in the ECU which affects how car shifts too as a by product of torque management"

 

i have a DTUK pedaibox plus and have to say in dynamic & sport it's a lot more responsive than with it disconnected and sport/dynamic selected.

https://www.audi-sport.net/xf/thread...review.356458/

But then it only really affects pedal pressuee/ travel but has scared the bejesus out of me when I drive the car wearing a new pair kf trainers/ shoes with a different sole depth

 

I *ONLY* drive the car in Dynamic (flag) mode with the transmission set in Sport mode and with the DSC either in track mode or turned entirely off. As such the way I'm experimenting with the car now is using those exact settings. It wouldn't make sense to compare one unaltered mode with a different altered mode. I'm telling you that the transmission is holding onto the gears longer than I am used to and that the shifts under acceleration are "softer" meaning less aggressive.

The extra "push" I am describing is not a result of remapping the pedal. That would be an enhanced throttle response, which I am not seeing except maybe in the first inch or so of pedal where setting the car into motion seems smoother and more precise. I am talking about a situation where you go to, say, half throttle and then as the car's RPM increase the "push" noticeably increases above 2500 RPM. It reminds me of Honda's "Vtec" or the variable intake geometry that was used in Lincoln's 4.6L quad valve motors. And I know that the Jaguar 5.0L has a variable camshaft capability but what is happening here is different (and I can verify it with the diagnostic data I've pulled from Torque Pro). It's not like a Sprint Booster or Pedal Box at all. I'm not saying that Alex did or did not remap the pedal... it doesn't feel like he did... but I am saying that what I'm trying to describe is not that.

I couldn't tell you what the car drives like now with dynamic mode off and in D because I haven't even tried that. I never drive that way with the exception of being on the highway. If there's something different in the way it drives down the road with the cruise control on at 75 mph I will let you know.

 

What I am doing a poor job of trying to describe is not that. I'm seeing differences in engine output that is related to the RPM of the engine, not getting more power based on less pedal movement.

 

That may come back over time unless Alex has done something to remove it. My car wasn't popping much when I put a tune on but seemed to sort itself out after a week or so.

 

I'm thinking there's a possibility that the ECU needs to "relearn" some stuff after it essentially has had the Spock's Brain treatment. I suspect the Transmission Control Unit may have basically reset as well. I'm in the weeds here... I understand, for example, what the timing and AFR and commanded AFR vs AIT *should* be and so on, but how to *get* there I'm entirely ignorant of. So I can look at the data and go "Yep, looks good" but the path to getting that data as a result is opaque to me.

 

What do your LTFT look like now at idle and under load?

 

I'm not at liberty to say. I CAN tell you that at full throttle they go to zero. . But that doesn't mean anything.