XF and XFR ( X250 ) 2007 - 2015

Velocity AP Tune + pulley

 
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Old 06-12-2018, 09:40 PM
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Default Velocity AP Tune + pulley

I'm looking for a tune/pulley combo for my 2010 XF SC. Velocity AP seems to be a reputable brand here, but I'm looking for some feedback from those with experience.
The VAP website (along with other sites like Eurotoys) claims a tune + upper pulley will put the 5.0L SC engine at or close to 600hp. That sounds great, but +130hp from a slight pulley change and a tune seems too good to be true. Does anyone have or know of any dyno data from before/after a tune+pulley combo? Even track data would be helpful. I've searched this site and others, but haven't found anything that supports the idea of a 130hp gain from this combo.

Does anyone have any feedback/suggestions as to why I should get a VAP combo, or for that matter, someone else's?

Thanks!
 
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Old 06-13-2018, 12:43 PM
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Yes do some searches as dyno results have been posted and you can judge for yourself. But the AP tune is very effective on my car.

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Old 06-14-2018, 09:05 PM
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Originally Posted by clubairth1 View Post
Yes do some searches as dyno results have been posted and you can judge for yourself. But the AP tune is very effective on my car.

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I'm not so sure they have been...at least not +130hp dyno results. I have searched, and I've come up empty-handed.
 
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Old 06-16-2018, 12:51 AM
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You probably are looking at rwhp dyno results, so you're not seeing the 130hp you're looking for.

Mine topped out at 519 hp. If you factor 12-15% driveline loss, you get between 590 and 610 crank hp, which is what the tune makers are quoting.
 
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Old 06-16-2018, 09:42 PM
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Originally Posted by 2010 Kyanite XFR View Post
You probably are looking at rwhp dyno results, so you're not seeing the 130hp you're looking for.

Mine topped out at 519 hp. If you factor 12-15% driveline loss, you get between 590 and 610 crank hp, which is what the tune makers are quoting.
Thanks for the info Kyanite. I've looked at whatever info I can find. Most, if not all of the crankshaft hp numbers people are giving are fabricated. I haven't found anyone running a pre/post tune + pulley setup on an engine dyno, so I really don't know why anyone uses crankshaft hp. Still, if post-tune/pulley hp is anywhere near 600hp, that's a 130hp gain and should be at least a 100hp+ gain on a chassis dyno. If yours made 519whp (I would be extremely happy with that number), I'm guessing you did in fact gain somewhere in the 100hp+ range. Did you do a baseline run before changing the tune, pulley, and other mods? Is your 519hp number STD, SAE, or uncorrected?
 
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Old 06-16-2018, 10:24 PM
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They use crank hp because that's what's given by the manufacturer for stock vehicles. I wish each car came with a "birth sheet" like many car audio amplifiers do with actual wheel hp. An no one is taking one of these engines out just to give crank hp numbers. That would be crazy.

Here are the graphs. The middle one was performed with the supercharger cooling pump in a state of limited effectiveness so heat soak was very pronounced.

You can search my posts for Jailbreak and you'll find the details of my tune.
 
Attached Thumbnails Velocity AP Tune + pulley-stock-vs.-tune-pulley-x-pipe-intake-9-5-15.jpg  

Last edited by 2010 Kyanite XFR; 06-16-2018 at 10:32 PM.
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Old 06-16-2018, 10:39 PM
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Originally Posted by 2010 Kyanite XFR View Post
They use crank hp because that's what's given by the manufacturer for stock vehicles. I wish each car came with a "birth sheet" like many car audio amplifiers do with actual wheel hp. An no one is taking one of these engines out just to give crank hp numbers. That would be crazy.

Here are the graphs. The middle one was performed with the supercharger cooling pump in a state of limited effectiveness so heat soak was very pronounced.

You can search my posts for Jailbreak and you'll find the details of my tune.
That's what I was looking for...thanks! Pretty nice TQ gain in the middle of the chart too.
I forgot your car is rated 40hp higher than mine is to start. I'll be running on a Mustang dyno rather than a Dynojet too(Mustangs read a bit lower), so I won't be surprised if mine is around 400whp stock. I'd love to see 500whp.
Did you do the upper or lower pulley?
 
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Old 06-16-2018, 10:41 PM
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And the change in peak hp doesn't give you the change in "power under the curve" and how the tune and pulley changes how the power comes on. It's a completely different vehicle now. So much a Jekyll and Hyde than a smooth, soft hit.
 
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Old 06-16-2018, 11:31 PM
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A friend of mine did his supercharged with the same tune, but no upper pulley as I did. I never got a chance to drive his as he was in VA at the time, but he said it was significantly more powerful than stock and seemed close to what he remembered my car feeling like when he drove it before I got my intake.

Depending on how you want your car to behave, I would either encourage or discourage the upper pulley. If you want the car to be smooth and drive better on a twisty mountain road, do tune with no pulley. If you want it to be VERY quick to respond with a bunch of torque on hand from very low in the powerband, do the tune and pulley. The reason I say this is less preferential for the twisties is that the power comes on hard and very good throttle control is needed to keep from overwhelming the tires and fighting traction control or wheelspin. No matter what, do the tune. It makes the car better in all ways over the stock map.
 
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Old 06-17-2018, 01:34 AM
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Originally Posted by 2010 Kyanite XFR View Post
You probably are looking at rwhp dyno results, so you're not seeing the 130hp you're looking for.

Mine topped out at 519 hp. If you factor 12-15% driveline loss, you get between 590 and 610 crank hp, which is what the tune makers are quoting.
Unless my maths is flawed (which wouldn't surprise me) then based on both my results and yours I would say that 10% driveline loss is closer to the mark.

If you assume that your engine still put out 510bhp (or 503 bhp depending on who you believe!) when it had the stock dyno run then that minus 10% = 459 (your number was 458.47).

Using the same calculation would put your after bhp at around 578.

I have applied the XKR-S tune to my 10 XKR and as you can see from the attached graph, if you convert the units mine, jumped from 463 rwhp to 503 rwhp so that would make mine around 558 bhp now.

Once my mechanic has put the 1.5lb pulley from VAP on my new supercharger snout I will be getting it fitted to my car and will get another dyno run done so I will be interested to see how close it gets to your numbers with just that plus the XKR-S tune.

Your comments about whether to go for a pulley or not being dependent on how you want the car to behave are very interesting. My biggest worry with adding the pulley is that I am going to end up just pulling massive wheel spins everywhere. The power added with the XKR-S tune already totally overwhelms the rear tyres and it is only going to get worse with the pulley. My only hope is that moving to Michelin Sport 4S's from Dunlop Sport Maxx's will sort that issue out but that change is likely to be two or three months away.
 
Attached Thumbnails Velocity AP Tune + pulley-2010dyno003combined.jpg  
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Old 06-17-2018, 08:37 AM
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Originally Posted by u102768 View Post
Unless my maths is flawed (which wouldn't surprise me) then based on both my results and yours I would say that 10% driveline loss is closer to the mark.

If you assume that your engine still put out 510bhp (or 503 bhp depending on who you believe!) when it had the stock dyno run then that minus 10% = 459 (your number was 458.47).

Using the same calculation would put your after bhp at around 578.

I have applied the XKR-S tune to my 10 XKR and as you can see from the attached graph, if you convert the units mine, jumped from 463 rwhp to 503 rwhp so that would make mine around 558 bhp now.

Once my mechanic has put the 1.5lb pulley from VAP on my new supercharger snout I will be getting it fitted to my car and will get another dyno run done so I will be interested to see how close it gets to your numbers with just that plus the XKR-S tune.

Your comments about whether to go for a pulley or not being dependent on how you want the car to behave are very interesting. My biggest worry with adding the pulley is that I am going to end up just pulling massive wheel spins everywhere. The power added with the XKR-S tune already totally overwhelms the rear tyres and it is only going to get worse with the pulley. My only hope is that moving to Michelin Sport 4S's from Dunlop Sport Maxx's will sort that issue out but that change is likely to be two or three months away.
Sorry in advance for the long response.

There are two things you need to keep in mind when trying to calculate driveline loss based on factory bhp claims:

1. Every dyno will read differently, even with the same car, on different runs and on different days.

2. The stock bhp ratings from the factory are minimum numbers. Every engine manufactured needs to be above that number. And because of differences in ring seal and a bunch of other tolerances being tighter or looser, the power created varies over a range.

So what we are trying to solve for in a basic algebra equation has two variables we don't have an actual value for, but a range. What we have available to determine the ranges is the engineers who make the vehicles word for what driveline losses are for a specific vehicle and builders who actually do dyno the same engine both in and out of the car. Problem is that the Jag guys haven't been talking and no one does the latter.

Therefore, we have to guess as to what makes sense for our cars based on industry standards. If we were talking Mustangs or Camaros, we could get a much better number based on before and after numbers. We just don't have them.

I did many hours of research (I research very quickly btw) on this specific topic when I got my first dyno results and did the math you did to see what my car was making stock. I realized that the 15% industry standard wasn't accurate for our cars, but since it's the standard, is what people will quote. That's why I give 12-15% as my range.

And unless you are really able to recalibrate your ankle/foot to be precise in your application of the skinny pedal, you won't get much relief from tire choice. The only exceptions are if you have all seasons (which you do not) or very worn out summer tires (which you probably do and from what I've heard about the Dunlops, they aren't that good when new).

My advice is to get the tires first, see how you do adjusting to the tune with the new tires, then decide if you will get wheelspin/tc intervention with more power. I've ridden motorcycles for decades and know about very precise throttle application. The trick was to get my ankle/foot to behave like my wrist/hand. If I didn't have this reference, it would be much harder to use the power available.

I love the pulley and the brute power it provides in a straight line. But it is much more challenging when tight corners are involved. I tend to leave the trans in Sport with the checkered flag mode (always forget what this is actually called) engaged and let the car shift for me. Shifting with the paddles just slows me down if I forget to shift and I hate to hit the limiter (which comes in at 6250 not 6500 where the solid red portion of the tach starts). So I have come to rely on the trans, which does exactly what I'd want 90-95% of the time anyway. The only thing the programming does that I don't always like is keep the engine in a lower gear (revs higher) than I would prefer. I find it easier to use the torque coming out of tighter corners than to really rev it since the throttle response is slower when revs are lower.
 
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Old 06-17-2018, 01:20 PM
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Just a comment on adding pulleys?

Depending on where you live if you do a tune and both upper and lower pulleys you "might" need to change your plugs (Colder) which is no big deal. Usually these will be copper plugs so they won't last anywhere as long as the factory dual Iridium plugs.

I got my tune from Stuart with Velocity AP and since I live in the Houston area he recommend that I do not install both pulleys because they have seen cars at that level need additional cooling mods.

I can't remember but I think we have a few guys running Meth injection to help with that problem? Maybe on the F Type forum?
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Old 06-17-2018, 04:38 PM
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Originally Posted by keithbradley View Post
I'm looking for a tune/pulley combo for my 2010 XF SC. Velocity AP seems to be a reputable brand here, but I'm looking for some feedback from those with experience.
The VAP website (along with other sites like Eurotoys) claims a tune + upper pulley will put the 5.0L SC engine at or close to 600hp. That sounds great, but +130hp from a slight pulley change and a tune seems too good to be true. Does anyone have or know of any dyno data from before/after a tune+pulley combo? Even track data would be helpful. I've searched this site and others, but haven't found anything that supports the idea of a 130hp gain from this combo.

Does anyone have any feedback/suggestions as to why I should get a VAP combo, or for that matter, someone else's?

Thanks!
hi there. if you look at their description writeup for all the other JLR tunes, it's a very similar description. I'd say they are making the claims that can be had with the newer Bosch management system and the older Denso system in our cars is not the same power level.
i got their tune over the winter and had a pulley done elsewhere by a guy who serviced my s/c coupling and oil and changed the rotor pack as tolerances were out of spec.
hope to go back to track in next couple weeks to verify if power levels allow for better than my old best time of 12.765 @ 111 i think. They are pretty responsive via email, so don't hesitate to contact them.
re: the pulley - i think the "performance pulley", offered by many companies and sometimes called a 1.5#, is about a 7% increase in s/c rotation over stock. it's definitely going to give increases in midrange boost potential, and of course elsewhere too, but it's not as if you're adding a pile of hp / tq with it. you're simply complementing the direction you're intending via the tune
back to VAP - in my poking and prodding, they seemed to indicate that it's a slightly modified xkr-s tune. remember the xkr-s was 2012 model year and the xfr-s was 2013. i think the power levels are quoted as similar or identical from jaguar, but different engine management systems (open to corrections from anyone here as I'm certainly not the foremost expert - lol) allowing our older denso cars to need to be matched to a similar denso based tune - enter stage left the xkr-s tune.. i asked VAP a number of questions and I'll paste the email back and forth as follows:

From:
Sent: Monday, November 27, 2017 7:40 PM
To: 'VelocityAP Info' <[email protected]>; [email protected]
Cc:
Subject: RE: VEL-JLR5.0DENSOECU

Hello. Base read file attached.
2010 xf supercharged
VIN: SAJWA0HE2AMR-----


In the printed instructions, Iím instructed to list requested features for the MOD file. Iíve listed my current and future mods in the mail chain below. Not sure what other things you can do but Iíd like:

- Higher rev limiter but still safe. Do you typically raise this at all? Iíd like it 300 to 500 RPM higher as it seems to cut out just when I want to shift which is always under the indicated redline and a real pain when trying to manually shift.
Yes, I usually bump it 200rpm, I spilt the difference and bumped 400rpm for you. Soft cutoff should be 7,000rpm and hard fuel cut should be 7,200. Compared to OEM spec of 6,600 soft and fuel [email protected],800.
- Remove top speed limiter?
Itís now set at 300kph
- Give me more power in lower gears where it often seems torque limited?
I cannot play with particular gear feels but have requested more torque down low and adjusted timing to help in this field.
- What else can you do?
I have a few XKR-S files, did what I could to try and get the throttle feel and response from the XKR-S into your file.
- Can shifts be made faster?
Nope..can only play with PCM not TCM. By requesting more torque this sometimes acts in a chain reaction to have the shifts feel faster, but nothing can be done as of yet to the TCMÖweíre working on a solution with a tool company, no eta though.
- Can you make it sound funky cool like a ďghost camĒ such as a pushrod cammed engine sounds at idle?
Not really, due to the knock sensing, the engine PCM will see this as a misfire and try to correct the issue. If it canít correct then the MIL will come on. I could play with the setting at which the PCM detects a misfire, draw back though is when an ďactualĒ misfire is present, it wonít be detected until severe. I can try to make the engine burble on overrun off throttle in higher rpm, might also make a pops/bangs sound. I went for it and edited your file to see if this can be doneÖlet me know if thereís any issues and if it sounds good.

so that's the content of our initial correspondences. Recently, i asked the following and am pasting the conversation:

From: VelocityAP | Tuning Support <[email protected]>
Sent: Friday, April 13, 2018 7:09 PM
To: 'Adam Janowski'
Cc: 'Stuart Dickinson' <[email protected]>
Subject: RE: VEL-JLR5.0DENSOECU


From: Adam Janowski
Sent: Wednesday, April 4, 2018 2:24 PM
To: 'VelocityAP | Tuning Support' <[email protected]>
Cc: 'Stuart Dickinson' <[email protected]>; 'Adam Janowski'
Subject: RE: VEL-JLR5.0DENSOECU

Hi guys, wanted to update you on one of your tuners I bought and downloaded as well as ask about fine tuning options.

I have the jag denso tuner with your modified xkrs tune in it. Iíve not driven a ton, maybe 700 miles, but not one hiccup such as a check engine light so great job. You raised my redline, to which I commented in emails below. I finally figured out that I have to be in sport and dynamic modes for manual control to take me all the ay up to redline. Just sport mode without dynamic will upshift on its own and a bit early. I donít remember that being as such before Ė I remember sport manual always giving full control. No biggie Ė I now know what to do and I could have been mistaken anyway. I do know you said you donít have control of transmission parameters and I assume those things are all trans related items.. Regarding revving the engine in neutral though, it used to limit itself to about 4k rpmís and now will rev all the way to redline in neutral. Iím a fan!
You could always flash back to the stock file and confirm the transmission shifting rpm without dynamic active. All the limiters in the ECU are lifted though to allow this rpm increase, which is most likely why in neutral or with dynamic active your allowed to rev to the rpm increased limiter. Iím assuming the TCU just limits or autoshifts when dynamic is not activeÖ

So my questions:
- In a previous correspondence, you made mention you might be working with another group to gain control of the ZF 6 speed trans. Has any furtherance been made in this regard?
Weíve had so many projects on our plate these past months that no steps have been made forward yet in any of the ZF flashing options. Itís something still on our project board, just not on the top of list yet.

- Can we make the tune a bit more custom for more power? I recall mention of me giving you some data logging Ė Iíll be honest in that I donít know how to do that. There are a few dyno shops within a 2 hr radius of me but they didnít seem to be able to offer any such service. One mentioned that he thought street driving would be a better datalog anyway.. is there a specific program I could use and do this on my laptop? Or?
We do have the 5.0 denso cars on our project list already though to dial in more power on a dyno along with dialing in a lower crank pulley with denso. Itís not something that will be done in the next weeks but do see this coming into action before the year is up. Main goal is to try and see how I can adjust AFR better on this ECU, itís very limited to adjustment.. To increase power more is really hard remotely even if the car is on a dyno. Itís one thing to create a safe+powerful tune and itís another to try and squeeze every once out of the motor when remote. One of the biggest issues is the AFR adjusts in denso.


Kind Regards,
Chris

Tuning Support
Velocity Automotive Performance Limited
2384 Government Street
Penticton, BC
Canada V2A 4W6
Phone: (1)236-422-3341
Velocity Automotive Performance, Inc.
 
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Old 06-17-2018, 10:54 PM
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Originally Posted by Adam J View Post
hi there. if you look at their description writeup for all the other JLR tunes, it's a very similar description. I'd say they are making the claims that can be had with the newer Bosch management system and the older Denso system in our cars is not the same power level.
i got their tune over the winter and had a pulley done elsewhere by a guy who serviced my s/c coupling and oil and changed the rotor pack as tolerances were out of spec.
hope to go back to track in next couple weeks to verify if power levels allow for better than my old best time of 12.765 @ 111 i think. They are pretty responsive via email, so don't hesitate to contact them.
re: the pulley - i think the "performance pulley", offered by many companies and sometimes called a 1.5#, is about a 7% increase in s/c rotation over stock. it's definitely going to give increases in midrange boost potential, and of course elsewhere too, but it's not as if you're adding a pile of hp / tq with it. you're simply complementing the direction you're intending via the tune
back to VAP - in my poking and prodding, they seemed to indicate that it's a slightly modified xkr-s tune. remember the xkr-s was 2012 model year and the xfr-s was 2013. i think the power levels are quoted as similar or identical from jaguar, but different engine management systems (open to corrections from anyone here as I'm certainly not the foremost expert - lol) allowing our older denso cars to need to be matched to a similar denso based tune - enter stage left the xkr-s tune.. i asked VAP a number of questions and I'll paste the email back and forth as follows:
What is your impression of the VAP tune on your car?
 
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Old 06-18-2018, 05:47 AM
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i'll be honest - i go through periods of doubt that it's any faster. thought of flashing it back to stock for a bit to see if slower..
i don't drive it enough - that's my biggest issue... usually once per week. I've done less than 5k miles in 18 months. when i uploaded the tune, I'd not driven it for 3 months.
a local friend has same exact car without the tune and he assures me there is improvement.
so i do plan on seeing drag strip improvement soon.
problem is our cars are already a strong punch in the face and if i punched you in the face and then again, just 15% harder, would you "feel the difference". probably, but the job was completed both ways.. my car is builds speed deceptively quickly, as do all of ours..
another note that comes to mind is that my charge cool pump was likely starting to fail and only getting worse since i uploaded the tune. it felt really strong in mid range at the initial throttle stab and then trailed off really quickly at full throttle, causing lots of wonder and doubt. thinking the pump was sometime not functioning at all.. I've only had the new Bosch pump for a week now, but seems to have consistent pull now.
most of my experience in the car has been that 3rd gear actually seems to pull harder than the lower gear, which seems backed up by everyone's assertions of torque limitations to protect the trans. tune didn't change that.
 
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Old 06-18-2018, 10:07 PM
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Originally Posted by Adam J View Post
i'll be honest - i go through periods of doubt that it's any faster. thought of flashing it back to stock for a bit to see if slower..
i don't drive it enough - that's my biggest issue... usually once per week. I've done less than 5k miles in 18 months. when i uploaded the tune, I'd not driven it for 3 months.
a local friend has same exact car without the tune and he assures me there is improvement.
so i do plan on seeing drag strip improvement soon.
problem is our cars are already a strong punch in the face and if i punched you in the face and then again, just 15% harder, would you "feel the difference". probably, but the job was completed both ways.. my car is builds speed deceptively quickly, as do all of ours..
another note that comes to mind is that my charge cool pump was likely starting to fail and only getting worse since i uploaded the tune. it felt really strong in mid range at the initial throttle stab and then trailed off really quickly at full throttle, causing lots of wonder and doubt. thinking the pump was sometime not functioning at all.. I've only had the new Bosch pump for a week now, but seems to have consistent pull now.
most of my experience in the car has been that 3rd gear actually seems to pull harder than the lower gear, which seems backed up by everyone's assertions of torque limitations to protect the trans. tune didn't change that.
15% is pretty substantial. If you remove 15% from our stock rating of 470hp, it brings you under 400hp, and pretty close to the hp rating of the non-supercharged car.
I think (hope) maybe you don't notice the difference as much because you don't drive it that often. We'll see though. I have a tuner and pulley from VAP on the way for my car. I might put it on the dyno tomorrow for a baseline if I get time.
 
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Old 06-18-2018, 10:58 PM
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I had my old XFR dynoed back in August 2015 and it showed 344.7 Kw (462 hp) at the wheels.
The only mods were K&N air filters, an H-pipe in place of the stock central muffler and after-market low restriction rear mufflers, which in theory should make very little difference to max power.
The stock factory figure for max power at the flywheel is 375 Kw/503 hp/510 PS.
Therefore based on my figures the drive train loss was 8.813%.
So either the minor mods made a difference or I had a particularly healthy engine or the dyno was a bit optimistic (Dyno Dynamics in shootout mode which I understand is not a particularly optimistic dyno) or the drive train losses on an XFR in good nick are quite low. In hindsight I reckon all of these factors contributed a little and my guess is that the true drive line loss is around 10%.
 
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Old 06-21-2018, 12:31 PM
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Originally Posted by keithbradley View Post
15% is pretty substantial. If you remove 15% from our stock rating of 470hp, it brings you under 400hp, and pretty close to the hp rating of the non-supercharged car.
I think (hope) maybe you don't notice the difference as much because you don't drive it that often. We'll see though. I have a tuner and pulley from VAP on the way for my car. I might put it on the dyno tomorrow for a baseline if I get time.
I'd be very interested in your before / after dyno results. I've not done that, but have always wanted to. I'll certainly post 1/4 mile times when i get back to the track.
so last night i got the tuner out and flashed it back to stock. Re: no throttle to initial throttle application, stock is much smoother as far as driveability. Decent part throttle torque, but anything into medium throttle or more is "softer" than the tune for sure. Drove a 30 min round trip. Parked it, reloaded the VAP tune and took back out after an hour or so. Definitely a rate of acceleration improvement over stock at all pedal positions. The transition from coasting to throttle application, even part throttle is much more abrupt. i think the best highlight of the tune isn't the extra peak HP, but the midrange increases, although the peak is good too.
 
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Old 06-21-2018, 01:08 PM
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Old 06-21-2018, 10:01 PM
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Thanks Tom; great info. Your power gain seems reasonable and realistic to me. I'm surprised it gained so much from the exhaust change though...I didn't see that one coming. Perhaps catless downpipes are in my future...
 

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