Stuart, considering that we seen many reports of differential failures with a stock tune, especially with V6S LSD differential, what are you doing to ensure that increasing rev limiter (which is also dictates launch rpm) will not make this problem worse? My understanding that more RPM means higher peak moments at the time of engagement. Are you also making first gear engagement slower to compensate?

 

Hi SinF,

We haven't seen any reports of differential failures. I don't doubt that there are a couple out there, at the end of the day there's always a failure rate no matter how low, on various components. However there's hardly a rash of failures and so it's not something we feel is a concern.

Raising the RPM limiter has nothing to do with launch RPM. You can't launch the car at 7000RPM because the torque converter will lock up at 2000.

 

Interesting. So you are not increasing launch RPM (i.e. neutral/stationary rev limiter)? So what does "At the moment we are increasing by 200RPM" in context of TCU means? I understood it as "TCU tune will launch at +200 RPM higher". Or were you just in general talking about ECU rev limiter (i.e. redline) ?

 

First you need to mention which type of powertrain your questioning?? 3.0L, 5.0L, RWD, AWD??

FYI, by increasing the neutral rpm limiter will NOT increase your ability to launch the vehicle at a higher rpm with a ZF8. This is the same as the max redline limiter, increasing redline will NOT increase the ability to launch a ZF8 JLR to a higher rpm. The "redline" edits being done inside the TCU is bumping the limiter to match the bump demanded inside the engine ecu. I cold raise the engine ecu to 9,000rpm, however if the TCU is not bumped, it'll still shift at the TCU max setting..etc. By increasing limiter in both ecu's, allows for a higher redline to be achieved.

FYI, the stock park/neutral limiter is 4k inside the engine ecu, this does NOT allow the user to launch the ZF8 at 4k ...increasing the redline to 6800,7000,9000 still won't achieve anything higher to launch..etc

Minus the available launch control on the 3.0L models, the stock stall speed is 2k. Once 2k is achieved with foot on brake, the converter locks and rear wheels will start to creep past the friction threshold of the rear pads. Surely there's a way to modify the stall speed of the convert to not lock at 2k for track files, but no testing has been done to prove a higher stall speed will benefit 0-60 on the AWD and/or RWD F-Type platforms.

 

Very interesting, thank you for explaining this to me.

 

Catastrophic Differential faIlure is due mostly to shifts not smoothly executed. Regardless of shift point, an AT is likely to execute shifts smoothly. Avoiding diff failure on an MT is a matter of reprogramming the driver.

 

Tell that to an Aisin trans...

 

Fortunately, F-Types don’t have those.

 

Any updates on this Stuart? How did the testing go?

 

Testing went very well. Picked up 2 tenths in the 1/4 miles from the transmission tuning!

 

Details, details!!!

 

So the overall times weren't spectacular, this is on a car with dual pulleys and tune but also running on rock hard Pirelli tires at nearly 5000ft DA. I think for a car that's running in the low 11's on a prepped strip at lower altitude with some stickier rubber we should see the transmission tuning allow the 11 second mark to be broken. You can see a pretty strong improvement in trap speed as well.

For some reason Dragy glitched out and said we were at lower altitude for the second run but the DA stayed the same. Clearly we didn't find a 400 foot lower airstrip!

 

Is it possible to tune ZF 6hp 28 gearbox? There are many examples where TCU upgrade is made on BMW's 6HP transmissions.

 

V6 base with lower pulley and VAP tune



Added the TCU tune and corresponding ECU tune. Long story short it’s definitely worth it.



Long story:

Shifting is noticeably quicker. It also seems like The shifting points match the next gear better. Like you feel the torque after the shift noticeably quicker, it’s surprising at first. Not sure if that change was engineered or if it’s just because the shifts are quicker, either way it’s nice.



To me the best part is the down shifting. Before the tune, spirited driving in S was almost mandatory because when i punched it, there was a delay before feeling the torque. I compensated by shifting down on the paddle. Now right after the automatic down shift it you feel the torque. Again I’m not sure why it feels torquier but it does.



Im not sure if anyone else enjoys doing it, but when coasting around 40 mph for the pops n crackles and Then WOT (or tap the gas first and then WOT) is where the downshifting torque is most noticeable.



Tomorrow I’m gunna push it to 120 to see if anything on the top end changes.



Overall Strong work by these guys. If anyone is familiar with bmws it’s reminds me of the b3 flash. Everything is just smoother but torquier when pushed.


Lastly to dispel an unfounded rumor. The tuner comes with credits preloaded.

 

Available for the 4-cylinder too?

 

As far as I am aware the 4 cylinder in the FType is still using this transmission. Not 100% sure though.

 

Anybody else have any reviews on this? Interested in getting for the base v6 with pulley and tune.

 

Have mine on its way via DHL as I type Also was able to get my new tires installed yesterday and my Downpipes/200 cell Cats installed this weekend. If the weather holds up I will get some experience and share it back here for reference. Mine is not a V6, but will still be a reference for how shifting occurs etc.. So far I have purchased almost every performance upgrade from Velocity AP, and is all top-notch! Looking to get my TCU tune Monday!

DC

 

To confirm, do these tunes work on 2019 and 2020s? I know we weren't sure about the 4-cylinders, but what about the other motors?

 

Stuart,
Any benefit for SVR vehicles as they come with more aggressive transmission mapping from the factory? Does this provide the ability to increase launch RPM? I saw Chris said it hasn't been tested but can we request it?

Thank you