As some of you may know, I have been searching for a tuner for about 5+ years. For various, mostly similar reasons, I did not feel comfortable with most of the tuners I either spoke with or researched, with many of my questions unanswerable, questions that others on this forum have raised many times. At the suggestion of another member, I contacted Stuart @ VelocityAp. I immediately sensed he knew tuning quite well, with an appropriate answer to every question I have posed to him. After several months and for various reasons I have finally been able to load a preliminary "test" tune, completely custom written per my specific requests for maximum potential power. Keep in mind this is a "test" tune. In a few days I will be reverting to the stock map in preparation for a booked day on a Dynojet on July 2nd. The plan is to get a baseline run and obtain a long list of OBD sensor data, then load custom map and do another pull and OBD data log. Velocity's tune writer Chris will then make various adjustments to the map as needed and we'll do another run and datalog and so on until he feels he has gotten everything out of the car he can.

Before loading the test map today, I spent the morning driving the car around at various speeds just to make a mental analysis of how the car felt with the stock map. Then this afternoon I loaded the custom one. My first impression driving in standard automatic mode was one of doubt and I decided there really was not much of a difference. Switching to sport mode was a completely story. The car leapt to life with intense ferocity, holding gears and only up shifting at 5K RPM. Going up on ramps to the freeway had me merging with traffic in seconds at over 100 MPH. For anyone who has gone from driving a 4.2 to 5.0 liter, this is what it felt like.

Stay tuned for when we do the actual tune, on the dyno, with numbers and data to be provided.

Anyone with a 4.2 interested in a remap should seriously consider speaking with Velocity.

 

I know exactly what you mean about going from a 4.2L to a 5.0L, particularly the low end torque in city driving. Are you going to do the smaller pulley and an X-pipe before you do the tune? Looking forward to the numbers.

 

I did the X-pipe and pulley 5 years ago in preparation for this...

 

Little hesitant to post an update as the re-map is not 100% complete, but I will go ahead with some of the results from today's 5 and 1/2 hour tuning session on a DynoJet with WinPep 8. We got our baseline run and then loaded the test map. Keep in mind Chris @ Velocity wrote a full map, not just adjustments to increase power and torque. He also had changed how torque is managed/limited, rev limit raised past 6500 and more. As I mentioned in an earlier post, this initial map did feel more powerful so I was surprised to see the second dyno run with this map was only about 15 more than the OE file with the 1.5 pound pulley (unfortunately I did the pulley so long ago and dyno'd at another shop that I don't have a true OE baseline to apply here only a guesstimate of around 10-15 more power over Jaguar stock).

Chris made additional maps after each run to adjust and optimize AFR & timing (the Jaguar stock map is VERY rich) but did run into a bit of an issue getting past 3K RPM as something in the ECU keeps over riding commanded AFR to make it rich even though trims are going to 0 open loop at this point. The end result was about 26 more hp/tq over the baseline or about 40 over the stock car (considering pulley). By the way max power is @ 6200 and max torque @ 4100.

I drove it a bit with the latest map and can tell it is even more powerful with traction being a bit of an issue at full launch. There are some other concerns too that are not relevant at the moment. Additional mods will most likely be made to the current map after I install the 200 cell catalysts in the next week or two and perhaps a way will have been discovered to overcoming the enrichment issue.

I have to say that it is a pleasure to work with real tuners and not someone who can't answer the majority of my questions because they are working with canned tunes and really have no idea what is going on.

Stay tuned... (pun intended)

 

Great stuff!


Are you using Velocity's 200 cell cats? I read in another thread that users were having problems with those cats causing all types of check engine lights and codes. Would like to know your experience.

 

Ive got 100 cell cats fitted with a custom and rarely does the engine light come in actual fact 3 times al whilst driving on the highway in 6 mnths , I just clear them with my odbII handheld unit

The other alternative is the tuner can manually turn off the codes during the tuning phase so the engine light will never appear

 

Rob,

I will be making my own cats this week or next depending on time in my schedule. Velocity modified the O2 sensors so there should not be any codes. FWIW I have gotten various quotes for power gains any where from 5-15 HP to 30-40 HP so it should be interesting.

 

My gain was 25whp but this was without the x-pipe

 

Was that gain from just cats or tune or both?

 

Thats from 100 cell cats plus a custom tune however on a positive the dyno I used is notorious for posting lower than normal outputs nevertheless I shaved .5 off my 1/4 mile after the tune & cat combo.

 

Not sure why I never updated this thread, but Velocity's tune ended up being worthless and was $1600 thrown away between the cost of the tune and hours of dyno time trying to fix their tune. Ended up removing it and having someone (Old Jaguar) with much more knowledge of the 4.2 denso ECU write a map with significantly more power (more than double).

 

Do you need to revise your signature to update "Cambo re-map 450+HP/480+TQ?

Can you give us more information about Old Jaguar and details about his tune?

Thanks.

 

Cambo = Old Jaguar.

Same place as the tune for my 5 litre came from and it is still the fastest (124.63mph) and quickest (11.925 secs) XKR on Dragtimes:

Fast Jaguar XKRs 1/4 Mile 0-60 Drag Racing - DragTimes.com

And although my car is traction limited, there is only one non-nitrous F Type running on road tyres with a faster 1/4 mile mph and that has an Old Jaguar tune too

Fast Jaguar F-Types 1/4 Mile 0-60 Drag Racing - DragTimes.com

Oh, and he holds the records for the 4.2 litre.

 

Yes along with the fastest xkr 5.0 , xkr 4.2 , 5.0 f-type (without nitrous) the old jaguar tune also has the fastest n/a 4.2 added to that list

 

Where does one find this “ old jaguar tune”?

 

Cambo (olg jaguar) is a forum moderator and sells the tunes here. It's interesting that Cambo chooses not to add my 1/4 mile time to the list , maybe he is very busy maybe not my track times by the way if corrected for Density Altitude are faster. My 1/8mile time is already faster than his even without correction, this is on my car which is a convertible and is heavier, and I'm still running open differential where Cambo runs an LSD . Should also mention that I have the highest Dyno numbers and Dyno gains to date which is the best indicator of power as Dyno numbers are always corrected for conditions compared to track time which very by a large margins due to conditions and are not the best indicators of power.
Either way I got respect for Cambos tuner Nick or "Moscow Leaper" is his forum name as he is a pioneer as he was one of the first to crack this ECU

Badicedog we should get your car on a dyno or on the track to see how it compares to the n/a car tuned by Old Jaguar

 

I’d like that. Kaiser just approved our new contract so life is good again. Give me a few weeks.

 

Your on Alex I would love to see how your tune stacks up against the one I currently have in my n/a 4.2.

 

Steve you got Dyno numbers or just track? Do you know your Density Altitude for when you ran? If you know the time and date it can be looked up I think on dragtimes.com

 

Are you OK? You seem a little upset?

I haven't replied to a single message, email or forum post of yours, in at least a year or so, since you threatened and tried to blackmail us (we still have all those messages, btw).