I believe the beep is fully off - hold for 5 seconds or so; a 3-second hold is partial off (TracDSC). I’m running Michelin 4SPS tires. They made a huge difference over stock PZeros when I put them on - easy 3/10ths off 0-60. Depending on the all-seasons you have, you might be leaving some time on the table here. Try a slow ramp up to 2,500 when you launch and shift to 2nd before redline - this is also advice from VAP when I spoke to them about their 10 second 1/4 run. And it’s working for me! With your Stage 3 setup, you should be able to beat my Stage 2 runs of 3.3. Let’s say you get to 3.2, well then you’re in the 10s my friend if your last run was 11.1

 

Tires a brand new Pilot Sport All Seasons. I don’t normally buy all seasons here in AZ, but when I bought the car the front tires were recently replaced with those and the rears needed to be replaced… anyway… haha.

The last two responses have both said the same
thing about shifting from first to second before redline. I assume then that you all are manually shifting the whole run? Or are you manually shifting from first to second and then slapping the shifter over for the auto to take over after that?

 

The advice I got from VAP was to shift manually from 1st to 2nd, then let the car go auto from there on out. No need to slap shifter over…VAP’s TCU tune will auto upshift even if you stay in manual mode (they can keep me honest here). This thread got me excited and just did some 0-60 runs. Consistently 3.5 seconds with this approach (at 5,400ft altitude). Adjusted for sea level, that’s ~3.25 (using Google AI). I am now Stg3 FYI with VAP’s TCU tune and rotors. I was running on some dirty (and vacant) industrial roads so I’m guessing ~3.15 with prepped/cleaner surface?

 

Very nice. We are set up the same other than the rotors. I’ll give that a try. Sounds like VAP’s tune won’t hold gear in manual mode at WOT.

About what RPM are you shifting at from first to second?

 

Correct, won’t hold gear at WOT. For 1st to 2nd, I’m shifting at about 6500 but want to try a little lower, a little higher and see if it makes a difference.

 

Went back to the track last night. DA was 3350. I’m car 75. Slip on the left was my first pass. Slip on the right is lining up with a stock 2021 F-Type (car 117). I really need to work on my 60’ times.

 

Reaction times are a tad slow don't you think?

 

Horribly…

Not concentrating on that right now. RT has no bearing on ET. I’m focused on launch technique and RPM while brake boosting. The more I get a feel for the car and how to best launch it, the better the reaction time will be. The car has 10’s in it with good air and a better driver. I can only control the latter.

 

Shhhh. Don't tell him that. That's the only reason I finished first!

 

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Hmm just read through this post, nice convo. Thanks for sharing, Rick5.0sc. Here's my list

1. On the table is a rouge controller set-up dropping better timeslips down. Gotta hate that. lol I believe his tale.
   1. I read a fear of losing the torque limiter function. Wow! all you need to do is download and save the baseline parameters before you start, providing a fallback strategy.
   2. I guess people do not fear a self-proclaimed "tuner" "adjusting" engine controller programming unabated. From what I've just read through, I don't think any of these mods add much power. I never felt the difference between 650 & 690 1/4 runs. I don't think anyone does. Can you guys feel 1080 to 1120? If the car is not more fun to drive, is the 0.4 boasting right worth the effort? Gradually modifying a machine that you really like, is the most expensive way to go racing, and least effective. My latest machine cost $35k all in, that's after I bought all new gear.
   3. The torque limiter cannot "protect" any driveline components. Which conditions would cause maximum engine torque demand and ability? Hint, Engine Torque is directly proportional to Rate of Fuel Consumption. Jaguar selected a Torque control strategy for engine management. They knew Torque Management gave them Full Supervision of the Fuel Burn Rate. This also gave them supervision of EPA demonstrations. EPA got much more pissed as auto makers learned how make hotrods yet still pass their gauntlets. A surprise rule clarification tactic attacked their flank. Adjusted rule, OEMs must demonstrate the maximum possible continuous rate of fuel burn shall be limited by ... No worries for team Jag, just limit the torque to match the arbitrary fuel burn rate. Test passed, sell some cars!!!
   4. What causes Jag's almost invisible goblin's return? This Jag engine in an F-Type is special. It cannot produce max torque near the starting line, insufficient RPM. Not the 60', 660', maybe not even at the 1320', IFF, you didn't muck about with their systems. Rather most often when you get in the uber high speed highway terror kind of mood. You may remember from school that Pumps drive a pressure differential, not an absolute output pressure. At the starting line the SC draws via vacuum from a 1 ATM supply through air supply ducts with just a bit of drag net .92ATM, 3kRPM w bypass OPEN, Engine sucks from SC via Vacuum of -1 ATM, engine sucks 1k times /min. How can it burn enough fuel to supply work with all pumps in slow motion? I'll need to calculate the F-Type's CASS critical speed.
   5. The piggyback attack... I know the best-selling controller for motorcycles is the power commander by Dyno-Jet. This have been working extremely well at least 25 years. Sold many giant stacks of these, for K, S, Y, H, & Harley. A few brit bikes got mixed in too. They crushed the market in every possible way. We never had a single return, results were always perfect, we coupled to our Dyno to build custom maps. Those were piggybacks that we coupled to every bike brand we saw. We used them for every crazy race bike thought which startled me awake the prior night. It used the OEM ECU to manage as typical. Modified operations did not involve the ECU. How is this not a better answer. That should allay some of the fears.
2. You can determine highest-power shift points with your acceleration curve on the track, from a Draggy or what have you. A dyno report should work up to half track. The back half analysis can only be done live.
3. You may run the best times by buffering the bumps. Start by lightly dragging the brake to smooth the bumps. The cool kids manually shift just after bumps to reduce wheel torque while on the bump
4. WTF, call your local VP fuel rep. They deliver any type of fuel, to your house or the track.
5. If the cost is too high, look for their rogue competitors.
6. Don't fix things that aren't slowing you down.
7. Leave on yellow, not green
8. Get lighter tires for race days, they are rotating, accelerating, un-sprung mass; everything bad. Don't talk, change it, then check your time... you're welcome
9. Dynos are great, but measurements are irrelevant, it's missing >100 mph of Ram-Air pressure. They are perfect for so many applications.
   1. You can easily provide proof of dyno reports. Just send pics of the atmospheric calibration settings, current date & time. But again, all dyno reports have no relevance to drag races.
10. Install a fuel cell for Methanol, or your favorite fuel. Solenoid control to switch fuel, and switch map. Never mix any fuel. I put in dedicated methanol pumps, lines, injectors, for complete isolation. Stop F'n around
11. Change oil after each pass when using >50% Ethanol or Methanol. Flush all that out when you get home
12. You must inject about 3x more Methanol by mass, than gasoline. We crank up the wastegate, a bunch, the controller just adds fuel from there as programmed. The map switch lets us change everything with the fuel source switch.
13. Race gas will not add power to an engine not setup to take advantage of the characteristics. Octane will reduce engine power at any value higher than the value which prevents knock. Higher Octane fuel burns slower because it's designed to combust at a higher pressure than a low compression engine provides. Gas engine fuel expands about 90% at 2X CC Volume. The piston runs away from the last 10% or so. If the fuel octane is higher than spec, more fuel gets left behind. Everyone claims they notice an improvement while driving with higher octane fuel. I have measured too many to count, engine power is always lower.
14. Higher combustion chamber pressure does not cause engine failures. It gets blamed often. 4x torque and/or power will not break an engine. At 60 PSI, that's about 4X the power. Force Squares with Velocity but is proportional to pressure. Overspeed rotation will pull a wristpin through a piston bottom at the start of the Intake stroke. Metals are 20x stronger in compression than extension. Engine internals pull apart from forces not caused by combustion. There must be 1000s of way to break an engine, too much power is not one. We ran an OEM Bottom Busa 2 years w/630 RWHP, carried a spare engine bottom every week but never used the spare.
15. Higher Transmission clamping pressure lengthens service life. If anything is slipping, it'll soon burn up. Don't let anything slip.
16. I agree, I do not mod my F-type, that is too expensive. When I go racing, I go with a race machine. I get much better bang for the buck
17. Get the money before you go racing

 

What the JB4 does is manipulate the MAP/TMAP sensor signal, which lowers the boost pressure (and in some cases charge temperature) reading that your ECU registers.
My MAP sensor failed without warning. The Jag ECU read the dead MAP

For example, if the engine is actually making 10 psi, the ECU might “see” 7 psi with the JB4 connected. Because the ECU thinks boost is lower than it really is, it keeps closing the supercharger bypass to try and reach its target. That results in more real boost, which makes more torque and more power.
This idea fails basic logic. If the ECU "sees" only 7of10 psi, that would indicate a lean condition. The ECU will lean the A/F ratio. Last I checked less fuel = less power. Without more fuel, nothing can be done to increase power.

The super charger cannot reach 10 psi if the bypass is open. The bypass valve has a closed position switch which reports to the ECU the moment it closes. The ECU will know that bypass is fully closed. Once the bypass is closed, nothing can "keep closing" the bypass because it is already closed, the SC is pumping at max, there is no opportunity here. My F-Type has never been modified. My SC bypass valve fully closes fully before my first shift.

"It does not change throttle position, pedal input, cam timing, or crank signals. Those systems are heavily monitored and altering them would immediately trigger faults."
How can you know this? Do you have the code? I doubt they'd change any of these since they have no value toward the goals


Now, if you already have a properly tuned F-Type that is making maximum safe boost and optimized ignition timing and it creates say 560whp , then adding a JB4 on top will not magically create more power if the real boost, fuel mixture, and ignition timing stay the same. If airflow and timing are unchanged, power will be unchanged because physics doesn’t allow it.

Now you declare how Physics applies.

Who defined "properly tuned"? Who published a White Paper to show how this boost level was proven to be both Maximum and Safe? Please send a copy for our reference. Did you hold conferences with Jaguar engineering during your ignition timing optimization research?
Did you know the virgin Jag ECU adjust a few ignition controls as it reacts to sensors monitoring performance of the CATs. It makes frequent changes, especially during the warmup period. The ignition can only do so much, so the ECU coordinates ignition operation with INT & EXh cams, & fuel injection to provide the best combustion possible. But wait, the ECU does a follow-up check on every combustion event.
I've been wondering how you studied all this material, perfected intersystem coordination, all while other products development continued.

Have you tested this?

One situation where a JB4 could show more power at the same boost level is if something else changes. For example, if the engine is pulling ignition timing because it’s hot, and the JB4 reports a slightly lower intake temperature than what’s actually present, the ECU may reduce how much timing is being pulled back. That can result in slightly more ignition advance and slightly more power but it’s not because airflow increased, it’s because the ECU is being less conservative.
This use of 'weasel words' is a common revealing indicator

You worked hard to craft this paragraph. The OEM ECU keeps everything on the edge; it does not operate conservatively at all. This strategy was fully explained in Jaguar's engineering documentation "Basis of Design", and "Technician Service".
If your scenario were to occur, engine knock sensors report to ECU, timing retards. Those events are not uncommon. And nobody cares what happens at idle. At WOT, any slightly elevated temperature will would

So in short:

Same real boost + same timing = same power
More airflow or more ignition advance = more power
This is misleading. This engine platform is Torque based, not Airflow, not timing


The JB4 can influence how the ECU reacts, but it can’t create power out of nowhere or rewrite the torque model.[/QUOTE]

 

From this morning.

 

[/QUOTE]


You are right on some things but mostly mostly not. You guys are underestimating the capabilities of this platform you will see how great this engine is as time comes and more tuning is available. The piggyback does trick the ecu into thinking is not making full power and no it will not run lean if you know what you're doing the ecu has something called fuel trims for or ecu is 30% +- aslong as you stay under that % the engine will run perfectly fine. If you want more power that's when port injection comes into play i actually got over 1100cc additional fuel methanol injection in my car works very good specially when my ecu hits those peak fuel trims in colder days and causes sligh lean spots the engine the methanol cools massively better and allows for leaner fuel ratios.
you said your stock car closes the bypass valve completely under wot but let me tell you the boost is not regulated by the valve is the throttle body. So what makes some people prefer a piggyback over a real tune let me explain the tune is only optimized for stock hardware so when you start adding modifications thats when you notice not enough gains why because again the tune is only good for stock hardware. A piggyback aslong as you supply the engine with fuel it will do what ever the blower is capable of producing which if you know alot about pd blower we know the tvs1900 is very good blower capable of 900+hp even the smaller tvs 1700 has gone low 8s in the 1/4. We have very limited tuning for our car. But people are blind to see the blame intake temps/weather simply do some research the main way of gaining power in an na car is timing look at the gt500/ an other similar cars they are pushing over 30 degrees of timing on pump gas when was the last time you seen someone playing with timing in our platform? Never because that dosent exists the most timing we see is 17-22 stock timing numbers. So the only option is a piggyback clear winner here simply go look at my social media my jaguar xf full interior is in the 5s 60-130 thats modded gt500 numbers 1000hp hellcat numbers. All that with simple mods pulleys and extra fuel

 

That's a lot of slope try finding a flatter road and better lock on satellite
Should look more like this!