Tuning results on a 5.0L NA XK
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Joined: Aug 2017
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From: Södra Sandby, Sweden
Well, here's the good and the bad of it...
Here are the first runs of pre tune and post tune. These were also respectively the fastest runs of the night.
Pre Tune. Post Tune
2.0808 2.0703. 60 ft
5.8039 5.7716 300 ft
8.8403 8.8117 1/8 mile
81.46 83.16 1/8 mph
13.3993 13.4046 1/4 mile
107.4 104.19 1/4 mph
So it was faster until the end of the race, then it dropped off 3 mph.
Here is the second best time, which in both cases was the last run of the night:
Pre Tune. Post Tune
2.1325 2.0749 60 ft
5.9046 5.8042 300 ft
8.9835 8.8524 1/8 mile
80.37 81.07 1/8 mph
13.621 13.4416 1/4 mile
103.19 107.02 1/4 mph
The date of the first run was 6/21/19 at 7:30:08 pm. Dragtimes is showing the DA that night and time of 3679. The second best run that night was at 10:18:33 pm. Dragtimes shows a DA of 3216 at that time.
There is no DA information yet in dragtimes about today, the 24th, but I can estimate it very closely.
The CORRECTED numbers of the first set of pre tune runs would be:
First run: 12,799 @ 112.513 MPH
Final run: 13.092 @ 107.434 MPH
I can estimate what tonights DA will be:
First run probably close to 3804 feet, second run 3368. So the corrected figures for this evening would be:
First run: 12.782 @ 109.332 MPH
Final run: 12.893 @ 111.649 MPH
Given that I was running on a tank that was above 3/4ths this time, and that I was running under 1/4 tank last time, you could make the argument that the car was carrying 8 gallons of gas at a weight of 48 pounds.
The car is ever so slightly faster. By a micron. Is it $1000 faster? I don't know.
Here are the first runs of pre tune and post tune. These were also respectively the fastest runs of the night.
Pre Tune. Post Tune
2.0808 2.0703. 60 ft
5.8039 5.7716 300 ft
8.8403 8.8117 1/8 mile
81.46 83.16 1/8 mph
13.3993 13.4046 1/4 mile
107.4 104.19 1/4 mph
So it was faster until the end of the race, then it dropped off 3 mph.
Here is the second best time, which in both cases was the last run of the night:
Pre Tune. Post Tune
2.1325 2.0749 60 ft
5.9046 5.8042 300 ft
8.9835 8.8524 1/8 mile
80.37 81.07 1/8 mph
13.621 13.4416 1/4 mile
103.19 107.02 1/4 mph
The date of the first run was 6/21/19 at 7:30:08 pm. Dragtimes is showing the DA that night and time of 3679. The second best run that night was at 10:18:33 pm. Dragtimes shows a DA of 3216 at that time.
There is no DA information yet in dragtimes about today, the 24th, but I can estimate it very closely.
The CORRECTED numbers of the first set of pre tune runs would be:
First run: 12,799 @ 112.513 MPH
Final run: 13.092 @ 107.434 MPH
I can estimate what tonights DA will be:
First run probably close to 3804 feet, second run 3368. So the corrected figures for this evening would be:
First run: 12.782 @ 109.332 MPH
Final run: 12.893 @ 111.649 MPH
Given that I was running on a tank that was above 3/4ths this time, and that I was running under 1/4 tank last time, you could make the argument that the car was carrying 8 gallons of gas at a weight of 48 pounds.
The car is ever so slightly faster. By a micron. Is it $1000 faster? I don't know.
Is it worth the money? For me yes but for others it's a waste of money!:-)
If you're happy with what you got for your money then money well spent!
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Joined: Jan 2010
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From: New Zealand
The 5 litre XKR is a different story though as I have gained over a second and 10 mph with a tune, x-pipe and smaller S/C pulley.
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Joined: Jun 2015
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From: Sydney, Australia
So it ran a slower 1/4 Mile time with the tune 13.3 vs 13.4 ??
Just to be certain when your vehicle ran the 13.3 was it just a once off or was it consistently posting that time ?? (Trying to establish the fact it wasn't a timing error)
Just to be certain when your vehicle ran the 13.3 was it just a once off or was it consistently posting that time ?? (Trying to establish the fact it wasn't a timing error)
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Senior Member
Joined: Jun 2020
Posts: 106
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From: Springfield, MO
The 13.3 and 13.4 are almost irrelevant, that's why I included the DA adjusted times. The weather around here (especially the barometer pressure) keeps life interesting. Someday I'd like to make a run at just our normal altitude (1219 feet) but during the summer I always end up racing in the 3000s.
But even if you took the 13.3 time and 13.4 time as absolutes, you need to look at the details... 13.3993 vs 13.4046. That's only .0053 difference. That's easily within the realm of how closely I staged to the line. 5/1000ths of a second's difference = no difference.
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Senior Member
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Posts: 106
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From: Springfield, MO
I have a way of dealing with traction. Last night on my fairly well worn no name tires I didn't so much as chirp off the line. You can make a set of street tires almost as sticky at launch as a set of drag radials. But like many of the things I've proven over the years, people just raise their eyebrows when I tell them the secret.
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Posts: 3,005
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From: Sydney, Australia
Sprint booster tune - so the car feels quicker yet has a slower time and mph hasn't changed .(mph has always represented a increase in power)
With DA - sorry but that ain't cutting it for me I do not know a single drag racer that quotes a time with these adjustments ." Yes I have a 10 second car but only with DA" anyone that would say a statement like that would literally get laughed off the strip .
In real world gains lets be honest there was no performance benefit I'm sorry if I sound harsh however I don't see why you should be defending a tune that has done nothing to your vehicle.
With DA - sorry but that ain't cutting it for me I do not know a single drag racer that quotes a time with these adjustments ." Yes I have a 10 second car but only with DA" anyone that would say a statement like that would literally get laughed off the strip .
In real world gains lets be honest there was no performance benefit I'm sorry if I sound harsh however I don't see why you should be defending a tune that has done nothing to your vehicle.
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Senior Member
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From: Springfield, MO
This is true. I have a ridiculously small dataset that I'm synthesizing information from. 6 runs. If anything it could be pointed out the the car is running more consistently.
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Senior Member
Joined: Jun 2020
Posts: 106
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From: Springfield, MO
And I'm not defending the tune. I'm saying that it as close to made no difference as to there being no difference. My "back of an envelope" calculations were there just to give some context and to dive a little deeper into the results. You are correct: The car is more "fun" at less than WOT and the end results would indicate no WOT power gains. So in the end it was functionally equivalent to adding a Sprint Booster.
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Senior Member
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From: Springfield, MO
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Joined: Jun 2020
Posts: 106
Likes: 57
From: Springfield, MO
My intention is to find out why my actual AFRs are richer than the commanded AFRs, plus I think it's shifting just a touch too late, but as it stands right now about the only conclusion you could come to is that it was money spent with no power gains.
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From: Somerset UK
De5in
It HAS however been a great exercise in the commonly raised 'tuning an NA X150' debate.
I am truly sorry that you've had to spend the considerable $$$'s as a guinea pig for others to learn by.
Guy's shall we have all send him $5 each, as it has been one of the most engaging threads (with detail) I've had the pleasure to read in a while on this forum?
But it has definitely now put me off getting my R tuned.
It HAS however been a great exercise in the commonly raised 'tuning an NA X150' debate.
I am truly sorry that you've had to spend the considerable $$$'s as a guinea pig for others to learn by.
Guy's shall we have all send him $5 each, as it has been one of the most engaging threads (with detail) I've had the pleasure to read in a while on this forum?
But it has definitely now put me off getting my R tuned.
Last edited by MarkyUK; Jul 26, 2020 at 10:15 AM.
Just going to chime in here quick as I am the tuner for car in question. First, Devin's 5.0 car is the first NA car tested with a tune. I have a tune for 4.2R version with significant increases and 4.2 na variant, we don't have results for 4.2 na on the track , but I know there are good increases there. Obviously we have to keep in mind that tune on NA car won't produce as big of a gain compared to the R.
Also I would not conclude that tune did not give gains on Devin's car going by the few good runs at hand. More runs and a Dyno would settle that.
Third, tune on Devin's car is not complete and Is a work in progress. As Devin have mentioned we still have to verify that the actual AFR is following commanded and few other changes that I won't mention here.
Also I would not conclude that tune did not give gains on Devin's car going by the few good runs at hand. More runs and a Dyno would settle that.
Third, tune on Devin's car is not complete and Is a work in progress. As Devin have mentioned we still have to verify that the actual AFR is following commanded and few other changes that I won't mention here.
__________________
2008 XKR Convertible, (mods: AlphaJagTuning ECU Tune , 1.5lb pulley, (200cel cats( are now melted), xpipe, Bosch 001 pump, 180 Thermostat.
Drag strip : 7.9sec 1/8mi 90 MPH . 1/4 mile 12.55 at 112.98mph
432rwh Dyno on Mustang Dynometer , Approx 511 crank HP.
2013 XJ 5.0 SC (Alpha Jag ECU, TCU tune, crank pulley), 600+ HP, 11.6 sec 1/4th mi 122mph, 7.6sec 1/8th mi
2018 Jaguar F-Type (AlphaJag ECU TCU, lower upper pulleys intake) 10.77 ,131mph ,700hp
2008 XKR Convertible, (mods: AlphaJagTuning ECU Tune , 1.5lb pulley, (200cel cats( are now melted), xpipe, Bosch 001 pump, 180 Thermostat.Drag strip : 7.9sec 1/8mi 90 MPH . 1/4 mile 12.55 at 112.98mph
432rwh Dyno on Mustang Dynometer , Approx 511 crank HP.
2013 XJ 5.0 SC (Alpha Jag ECU, TCU tune, crank pulley), 600+ HP, 11.6 sec 1/4th mi 122mph, 7.6sec 1/8th mi
2018 Jaguar F-Type (AlphaJag ECU TCU, lower upper pulleys intake) 10.77 ,131mph ,700hp
