ECU Tuning Group | Jaguar XF/XFR ECU Upgrade
#81
And dont forget, this was my opinoin when I say " I dont feel the kick in the butt that much". If you rode in my car you may say very different, everyone concept on whats fast is different. So I may have chosen the wrong words, maybe find a car that has this flash in your area and go for a ride in it?
#82
UPDATE: I let the wife do some driving since I had a few drinks and I told her to drive it hard so I can feel the kick in the pants. I must say when she nailed it everytime it held me in my seat good and hard. You can feel the car is very heavy like a tank but has lots of power to push it. So my outlook on it now is it does give a kick in the pants feel
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grounded4now (10-21-2012)
#83
Thanks!
#84
Engine torque is multiplied by the transmission gearing and rear end ratios, and the important thing is how much torque the car makes at the wheels. Since lower gears multiply engine torque more than higher gears, we can generally get more power to the wheels by holding each gear to redline, or close to it (unless engine torque falls off significantly near redline, which the 5L S/C does not). Shifting up to the next higher gear means the engine's torque isn't being multiplied as much. So the torque we're interested in for maximizing acceleration is the torque made at high rpms.
Horsepower and torque are related mathematically with hp = tq x rpm / 5252. You'll find that a slight increase in torque across the powerband will yield an ever greater increase in hp as rpm increases beyond 5252 because of that relationship, where a 30 lb-ft increase in torque is exactly a 30 hp increase at 5252 rpm, but becomes a 37 hp increase at 6600 rpm. Since the engine will be operating at only high revs during maximum acceleration, knowing the increase in horsepower is the most meaningful measure.
Some engines have a very pronounced torque peak in the mid rpm powerband, and falls off at higher rpm. As the car accelerates at full throttle in any given gear you get pushed back into your seat more forcefully at its torque peak and you "feel" the strong torque. But as you rev beyond that the engine makes less and less torque, less and less tq at the wheels, and acceleration falls off until you up shift. Revs drop back into your higher tq range, but you've given up the advantage of the lower gear ratio, and acceleration again suffers for it.
So that's a real quick and dirty on why torque at high rpm makes the car accelerate faster, and why the increase in peak horsepower is more indicitive of acceleration than the increase in peak torque. In the case of the 5L S/C, you'll notice the torque peak is below 3000 rpm, and while that makes the car "feel" powerful for daily driving, its the engine's ability to retain a high portion of that to redline that makes it accelerate as well as it does, and the fact that the engine's factory rated hp (ie 510 bhp) is higher than torque (461) is a good indication of that desirable powerband.
While wheel horsepower always measures lower than factory brake horsepower, BigCat09's very serious increase in whp to 475 will have a pronounced impact on acceleration, even if the more modest increase in torque doesn't make as pronounced an impact on the "feel".
There are several good articles on-line for those wanting more in-depth information by doing a Google search under "horsepower vs torque".
Bruce
Horsepower and torque are related mathematically with hp = tq x rpm / 5252. You'll find that a slight increase in torque across the powerband will yield an ever greater increase in hp as rpm increases beyond 5252 because of that relationship, where a 30 lb-ft increase in torque is exactly a 30 hp increase at 5252 rpm, but becomes a 37 hp increase at 6600 rpm. Since the engine will be operating at only high revs during maximum acceleration, knowing the increase in horsepower is the most meaningful measure.
Some engines have a very pronounced torque peak in the mid rpm powerband, and falls off at higher rpm. As the car accelerates at full throttle in any given gear you get pushed back into your seat more forcefully at its torque peak and you "feel" the strong torque. But as you rev beyond that the engine makes less and less torque, less and less tq at the wheels, and acceleration falls off until you up shift. Revs drop back into your higher tq range, but you've given up the advantage of the lower gear ratio, and acceleration again suffers for it.
So that's a real quick and dirty on why torque at high rpm makes the car accelerate faster, and why the increase in peak horsepower is more indicitive of acceleration than the increase in peak torque. In the case of the 5L S/C, you'll notice the torque peak is below 3000 rpm, and while that makes the car "feel" powerful for daily driving, its the engine's ability to retain a high portion of that to redline that makes it accelerate as well as it does, and the fact that the engine's factory rated hp (ie 510 bhp) is higher than torque (461) is a good indication of that desirable powerband.
While wheel horsepower always measures lower than factory brake horsepower, BigCat09's very serious increase in whp to 475 will have a pronounced impact on acceleration, even if the more modest increase in torque doesn't make as pronounced an impact on the "feel".
There are several good articles on-line for those wanting more in-depth information by doing a Google search under "horsepower vs torque".
Bruce
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#86
#88
#91
If you come up to Massachusetts I can install the Rica program in your car.
RICA Engineering - Performance and Economy Tuning - Specialists in Volvo Tuning, BMW, Audi, VW, Jaguar, Mercedes and most other makes and models
RICA Engineering - Performance and Economy Tuning - Specialists in Volvo Tuning, BMW, Audi, VW, Jaguar, Mercedes and most other makes and models
#92
So what are the stats? I emailed rica and didn't get a reply. What's the hp increase in a us spec car? 1/4 mile improvement? 0-60mph improvement? Is the top speed limiter removed? If so, what's the top speed? What the price in US dollars? And how do we insult all the tune in the NY/NJ area??
#93
Is it just me, or is there something missing when there are no empirical track times for any tuned cars? To just say that a tuned car will have 560 hp, but have no proof as to how that power translates in real performance, makes it sound like any gains could potentially be academic or fictitious.
#94
Is it just me, or is there something missing when there are no empirical track times for any tuned cars? To just say that a tuned car will have 560 hp, but have no proof as to how that power translates in real performance, makes it sound like any gains could potentially be academic or fictitious.
#95
#96
Is it just me, or is there something missing when there are no empirical track times for any tuned cars? To just say that a tuned car will have 560 hp, but have no proof as to how that power translates in real performance, makes it sound like any gains could potentially be academic or fictitious.
BigCat09 has posted video's, time slips, etc about the tune. Since we have introduced this tune, not one complaint has been made. It seems like the only people who "talk", are the ones who have not purchased the product.
#97
BigCAT 09 did the test, Results are in.
BigCat did it done deal. He the flashed his ECM himself with the ETG supplied laptop. Installed the pulley by hacking if off, but still did it himself. Now he informed us that they will loan a pulley puller for that job. SO simple. He dropped in a couple of K&N filters and bolted on a staniless steel exhaust. Going from 470 SC or 510 R to 580 HP is a good result. I am confident his result is the best and the simpliest. If I was not sending my son to college I would jump in no problem and follow his plan. Nice job Big Cat. You sold me.
Last edited by edobernig; 11-20-2012 at 09:14 AM.
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BigCat09 (11-20-2012)
#98
ECU states “…Through the months of testing and data logging, we noticed that there are absolutely no internal differences, other than exhaust (XKR-S), between the 470hp, 510hp, and 550hp Jaguars. As stated on our previous blog (Jaguar XKR-S ECU Tuning), Jaguar placed limiters within the software that affect each model differently…”
So, why can’t the 510 hp XKR be raised to 605 hp, the same as the XKR-S? Is the exhaust the only thing between more hp?
So, why can’t the 510 hp XKR be raised to 605 hp, the same as the XKR-S? Is the exhaust the only thing between more hp?
It's a crime that more companies (or some genius) hasn't come up with a inexpensive way to tune these cars software. It just sucks!
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Need4Spd (12-21-2012)
#99
Why haven't some of you contacted Rocket Sport Racing to have them sell you the tune they use since they done it already and just flash everyones cars and make some $ off it?
The only part I see they did different then the rest of us is they made some kind of intake for the XFR which I have not been able to see. Anyone find a picture of the hood open so we can take a peek?
And the XFR they used looks like a 09 XF fitted with the 2010 motor and trans and not a 2010 XFR. Look at the body parts as the ylook like the 09 styling?
The only part I see they did different then the rest of us is they made some kind of intake for the XFR which I have not been able to see. Anyone find a picture of the hood open so we can take a peek?
And the XFR they used looks like a 09 XF fitted with the 2010 motor and trans and not a 2010 XFR. Look at the body parts as the ylook like the 09 styling?
#100
Why haven't some of you contacted Rocket Sport Racing to have them sell you the tune they use since they done it already and just flash everyones cars and make some $ off it?
The only part I see they did different then the rest of us is they made some kind of intake for the XFR which I have not been able to see. Anyone find a picture of the hood open so we can take a peek?
And the XFR they used looks like a 09 XF fitted with the 2010 motor and trans and not a 2010 XFR. Look at the body parts as the ylook like the 09 styling?
The only part I see they did different then the rest of us is they made some kind of intake for the XFR which I have not been able to see. Anyone find a picture of the hood open so we can take a peek?
And the XFR they used looks like a 09 XF fitted with the 2010 motor and trans and not a 2010 XFR. Look at the body parts as the ylook like the 09 styling?