TomaS8

You will always get more HP out of a forced induction motor. 2.0T rocks!
I've done some mods before the tune, Carbon cleaning, hotter APR coils, new intake manifold, IM spacer, deleted both or should I say all four resonators, oil heater bypass, SAI delete. I will do a lighter crank pulley next. Some of these mods are not that crucial for power but everything adds up. I don't know what my power gain is but the car is totally different now. It accelerates brutally.
I did both tunes at the same time, ECU first and immediately TCU. The TCU is crucial in that it releases the power from the motor quicker without wasting it around the trans, clutch, TQ, etc.

Mike_k

Shift times on the D3 S8 are absurdly slow. It's hard to comprehend that BMW was offering their sport automatic transmission in the 5 series at the same time this car was being produced. That car (I believe) had the same transmission but with very different tuning. The S8, above all, is a luxury car. So to keep those shifts soft, they dial back the torque and lower line pressure in the transmission through the shifts. This gives you a luxurious, smooth shift but not a very satisfying one in a performance sedan. I'm going in for the JHM ECU/ TCU tune on my S8 next week. I adore this. Like, irrationally love this car. Like so irrational, I sold my low mileage Lemans Blue e39 M5 when I needed garage space because I enjoy the S8 more. But the transmission is painfully bad. Upshifts are slow and clearly programmed for comfort over performance. The paddle shifters are merely a suggestion and seem to have a dial up connection to the car's computer. I'm hoping these tunes are as good as everyone has said that they are. I don't need more power but if I can improve the transmission on any level it will be money well spent.

TomaS8

Please, keep us updated on the tune.

aTOMic

I'm curious about the price. I looked at their site and didn't see this option.

TomaS8

These prices are for a D3 S8. I don't know the car that you have.
I ordered all three. You need the their dongle, other cables will not work.

https://jhmotorsports.com/jhm-tuning...l-v10-fsi.html

https://jhmotorsports.com/jhm-tcu-ti...d3-s8-v10.html

https://jhmotorsports.com/catalog/product/view/id/6818

aTOMic

Thanks; I guess they don't offer an option for the 'lowly' 4.2L Probably just as well; then I'd need paddle shifters and, on top of the necessary trans flush I've been putting off, that's a lotta cash!

Ethan.J

It's been a while, and i'm unsure if you still have the car... but I'm curious as I plan on doing this myself!

How did the ECU tune effect MPG, I know with the APR ECU tune it brings it down quite a lot for an additional 20(if even) WHP. Mainly would like to do the TCU flash but it requires their ECU flash as well.

Since it's been a few months, did the tunes end up causing any side effects to the motor/trans?

TomaS8

I don't have the car anymore, it was totaled parked right in front of the condo by a hit and run driver,
I never measured MPG, I didn't want the stress of fuel consumption ruin the enjoyment of my right foot. Tuning the car is the best mod that I did to my S8 and the TCU tune was so very necessary. The enjoyment increased 100fold.

Ethan.J

Oh man. I just saw the picture of it, my heart absolutely shattered, my condolences. Very understandable, though! The s8 has some extremely lethargic shift speeds, you're the only person I've heard of doing the JHM tunes so I'm glad they're worth it.

RobertISaar

I've done both, I added some extra complexity as well(relocated O2 sensors to avoid engine pull). Initially, I flashed both at once, just recently changed back to stock(tcm first) to make measurements/validate real-world improvements. Your mileage may vary. Currently, the tunes cost far less than what I paid and if you're wanting to push your car as far as it can go, it's a necessity.

ECM: at anything above 10ish MPH, the JHM calibration is overall better. I don't like that the port divider motor(not the air path length/resonance tuning flaps that are break-happy) is always locked in the full open position rather than opening/closing based on torque demand, I believe there is a benefit to be had to that system staying active. The lower commanded coolant temps bring oil temps down as well, which should help with the PCV overload issue the 5.2 is stuck with. Power increases are felt at 3000ish and keep going all the way to redline. No apparent change good or bad for fuel economy? If so, it's a slight improvement over stock, but the margin is pretty small.

Below 10mph, I prefer the OEM calibration. The lowest speed drivability the Audi powertrain engineers dialed in can't be beat. I'm going to see what all can be changed here to mesh the two.

TCM: this is big. Much bigger than the ECM. Full throttle shifts go from worn out GM 4 speed automatic to something I can best describe as "urgent". Very reminiscent of the early DSGs. I think the shift points have been heightened to some degree as well, I don't think the original calibration would allow running above maybe 6800 before a forced upshift starts while I've seen a couple 7000 and 7100 with the JHM setup. Light throttle have also been noticably quickened, 1-2 and 5-6 are felt the most. 5-6 in my opinion is too far, I got into the habit of forcing an upshift around 35 with the smallest amount of throttle applied so that when 40 or 45 came around, I didn't get jerked around.



Overall, this is easily the cheapest way to add this degree of speed to the S6/S8. I think with a little blend work, the JHM calibrations will be what Audi should have released when new.