A JB4 as in Berger Motorsports JB4 piggyback? I was unaware they made anything for Jaguars... their website certainly doesn't say anything about it. While Berger's JB4s are highly respected in the BMW community, it is important to understand that these are a piggyback tuner and are effectively lying to the engine controller to get a desired outcome. In many cases this can remove safeguards (like torque management, in addition to others) in favor of making power. You'd be the first person to even come close to the 10s on a stock pulley ratio, so I'm highly skeptical of the safety/reliability of this setup.

 

So many questions… haha.

I’m new to the AJ133 engine platform, but this seems pretty crazy. I guess anything is possible ONCE…

When tuning my VW, torque management was at the forefront of forum discussions to keep Uncle Rodney partying on the inside where he belongs. Some guys were pushing high (relatively speaking) HP numbers, but really dialing down the torque management off the line in the lower RPM range to keep from throwing rods. This may be an apples to oranges comparison since we are talking about a DSG transmission with launch control vs the ZF 8 speed.

Companies like EQ Tuning (VW’s) really prided themselves on their tunes to give the end user a bump in power without sacrificing reliability. I have to assume VAP and others are doing the same for this platform. I’m not willing to risk a JB4 or custom tuning that will turn off torque management altogether for a faster slip.

While I was a little disappointed this last track day, I’m still enjoying the hell out of this car and don’t worry that it’s going to detonate the next time I get on the freeway under WOT.

That slip there ☝🏼 seems to be a HUGE roll of the dice.

 

they don't make anything for jaguars but you can make them work the ones made for infinity q50 is what I use they only override torque management everything else stays in place I've ran this device in for over 3 years in my daily driven jaguar xf with no problems an has gone 10.1@137mph with basic bolt ons. The same devices are used in $100k bmw g80s without problems like I said all the safy parameters stay in place

 

we don't know the limits limits of this engine people throw numbers here on the forums but have no idea what they are talking about they real number nobody knows. So me trying to get everything out of this car is my goal and this is not a one time deal I've ran this device for over 3 years in my daily driven car traping almost 140mph with simple modifications and keep in mind is the only 6peed transmission over 4300lbs not the aluminum lighter newer Jaguars. Overriding torque limiters does not hurt the engine if the engine internals can handle the power the engine will have no problem making power. So my question to you guys is why waste money only pulleys and parts if the stock hardware can make even more power just by tuning torque management? Why keep buying parts power is power right? My point it islf you can make 650 with good tuning stock hardware and 600 with base tune and dual pulleys why have all those modifications and still make less power? Anyway that's awesome seeing other jaguars being raced

 

Of course my opinion may seem biased, but here’s my view.

The JB4 or similar piggyback does not change ignition maps, fuel targets, cam timing, or torque limit tables inside the ECU.

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.

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.

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.

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.

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.

So in short:

Same real boost + same timing = same power
More airflow or more ignition advance = more power

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

 

I find this absolutely terrifying. In addition to what Chris mentioned above... not only are you using a piggyback controller, which is already scary, but you're using one for a completely different OEM. I can't imagine even the piggyback manufacturer would recommend that. You say the safety parameters stay in place but also mention torque limits being removed... which are there for a reason. Maybe it's not to save the engine, but no OEM is going to limit performance just because. They do it to protect components; maybe the transmission or differential unit. Regardless, you're removing safety features.

 

mmm so im confused isn't that what we all want more power? Then why are all these guys buying bigger superchargers and pulleys and cams of the stock hardware can make more power and go faster? You do realize tuning an ecu does the same thing right? Set the torque limits higher to allow the ecu to target more power my point is all you guys are runing basemaps which are designed to work with the oem hardware and by swapping to bigger blowers/ pulleys that same tuning is actually hurting the performance just like the person above posted I've seen this hundreds of times and I even tested it my self by loading a base tune in my car after that every time I added another part it got slower and slower

 

I am sure many of us would genuinely welcome the opportunity to better understand your thought process. However, it is difficult to follow your position when much of your response is written as one long run on sentence.

 

You have me thinking more about a TCU tune now…

I admire your bravery and creativeness/ingenuity. My bravery has to be directly proportional to my budget, and right now I’m not willing to be super brave… haha.

The only similarity between the car you are racing and the one I’m trying to go a little faster in is the engine, if I’m not mistaken. Different ECU, different transmission, with the addition of a transfer case, front differential, etc. I wonder how your approach would work apples to apples?

 

Yes my cars are older only similarity is the engine the newer cars have more advanced over my cars for example the lighter aluminum body the 8speed transmission and newer ecu. And believe me you won't hurt that engine doe to high hp this engines are bullet proof in terms of making power don't be afraid of pushing it hard what you are seeing is not knock is the ecu shutting things down to its targeted limiters. And I guess we will find out very soon im saving up for an f type awd first thing I would do is a piggyback which im positive it will go 10s right out of the box f types already run mid 11s stock so 5 tenths should be very easy just blows my mind how all these f types are struggling to run high 10s with dual pulleys and transmission tunes and all those mods when in reality stock hardware will go 10s very easy I love this platform an I hate to see people think they are slow when in reality the engine just wants more

 

How are the guys with the bigger superchargers making more power if the ECU is the ultimate limiter?

 

they are not making more power all those numbers are fake claiming 750+hp and still running low 11s how is thay possible non of these heavily modded jaguars make over 660hp if they did we would see them run mid 10s there are other cars we can compare them to for example a 500hp bmw m3 g80 similar weight if not heavier the run mid to low 11s an that's just one example so nobody can convince me theres 750hp jaguars I been racing for a long time and this is actually sad. There's alot of videos on YouTube on these f types running mid 11s 550hp similar times as a stock bmw g80 if the 750hp f type was real wouldn't it be running low 10s? Because everyone knows a 750hp bmw run lid to low 10s how are we not seeing that from the f types I personally know someone 800hp+ g80 traps 139-142 mph in the 1/4 the 750hp ftypes are nowhere near that just my opinion.

 

Hmm interesting - I haven't seen the timeslips from any of the cars with upgraded superchargers, but I have seen timeslips from some properly tuned stage 3 cars, 650ish with 127-128 mph trap speeds - at least 4-5 mph higher than a stock car, though there are so many variables here. The modified cars with lower trap speeds I always thought were knock limited for one reason or another (fuel, heat, tune, something else wrong with the motor). Maybe traction control is still interfering somehow. Not doubting you, just would like to see more hard info about what the ECU is actually doing, and results, very interested to see what you come up with - always good to have new folks experimenting with and developing the platform. For me I stay conservative, I can't afford to replace my motor.

 

With the TVS2300, 750BHP is achieved.

Are you claiming these are fake power numbers advertised by us at VAP?

 

The issue here is that this is a sample size of 1, with a piggyback controller not even developed for this vehicle, that removes component safety feature. I fully appreciate and encourage people to push the boundaries of what's possible; it's how we make advances on a platform and people learn overall. That being said, we have no idea how safe or dangerous this setup is with a sample size of one, and claiming its safe, can make all this power, and that everyone else is lying about what their offering is dangerous misinformation.

I haven't seen any tuners claiming 750hp on just dual pulleys, but in general, VAP and others have a history of making additional horsepower in a safe/reliable manner. These trusted performance increases haven't been mind blowing, but enough to get people into the 10s on dual pully setups. That's just facts. Now (just an educated guess here), I imagine the torque limits (not horsepower limits) are there to protect the transmission or driveline from failures. As a result, leaving those in place would limit the performance gains, specifically off the line and lower in the rev range; I've always said this vehicle launches poorly for an AWD vehicle and if someone were to completely remove the hardware limits, you could theoretically reduce the quarter mile time by several tenths... maybe that's what we're seeing here.

 

Not debating you because you're on the money, but it's worse than you think..

One of the biggest misconception is believing that JB4 directly increases the torque limits. The purpose of the JB4 is to allow more boost by skewing the air volume results.

Allowing more boost to be created over the ecu calibration requests.

The ecu gets confused because the airflow models are much less, so the ecu commands more boost and never reaches its max target.

This on it's own, forces the ecu to generate more torque and power earlier on and carries this skewed result till throttle pedal is released.

You're right on it being unsafe, everything that is reliant on knowing the amount of airflow and things like torque, become misinformed. For example, the transmission works of pedal angle and torque generated. Faking the torque results means the shift patterns are no longer correct. Someone could claim they feel no difference in shift quality, but the transmission increases pressures and clamping forces the higher torque reaches. This means a lower displayed torque reading by JB4 will provoke less clamping force, resulting in advancedpremature wear of the transmission internals.

 

well theres only 2-3 f types in the 10s with weigh reduction/dual pulleys and other bolts ons so I wouldn't be convinced a dual pulleys f type would run 10s all day long as you see the person that started the thread here has all that done and is struggling to hit 10s take a look at the draggy page all f types are stuck in the low 11s. And no thats not how torque works torque means power in an ecu the ecu can't measure power but it can measure torque very accurate using all the sensors it has and when you disable or set the torque higher you not only get power at the low end more power comes in all across the rpm range for example one of my cars makes 11-13p psi dual pulleys no piggyback enabled and with piggyback enabled i see 20psi all the way to redline

 

"Torque" is not disabled by JB4 or any piggyback, it's manipulated to read lower because it's skewing airflow modle mapping.

The way a "Tuned" software would generate less charged pressure than with a "Tuned file+JB4", is if the tuned file is not commanding pressure and the bypass is opening OR the torque requested early in pedal demand is less. This world result in the JB4 equipped car reaching a higher torque because more was commanded at an earlier point.

However, this can still be done in the tuning file by lifting torque request from pedal earlier in chart.

Nonetheless, this has nothing to do with the JB4 disabling torque limits, it does not have that function.

 

I never said or mentioned vap i simply see alot of jaguars claiming 750+hp but aren't running the numbers they should math ain't mathen specially on Facebook groups the f type above traping 121 122 thats stock f type numbers pretty easy to estimate power based on trap speed sample math

 

disabling overriding same thing my question is if it can be done trough tuning than why are we not seeing the same 1/4 or 60-130 numbers as my piggyback equipment jaguar? An let me remind you its not a gutted car like alot of people think is full interiour 4288lb. I get hundreds of logs from jaguar owners and I see very similar torque cap almost as if they all have the same tune i understand alot of tuners outhere like to play it safe but then again why upgrade superchargers pulleys just raise those limiters in the tune power is power right doesn't matter how it comes.