Re Flash tuning JK TJ Petrol

[MightyMouse]

Good to hear that you understand and can resist the urge to cheat. Its quite depressing to hear these stories again and again - "dyno shopping".... going to the operator who can create a graph with the biggest numbers regardless of reality.

And you right about drivablility - the shape of the curves is extremely important - peaky power can give a high maximum number but actually be quite slow under real situations.



Just BTW the atmospheric correction factors aren't on the printouts so even your dyno in the hands of a shonky operator is vulnerable to "cheating"

[4Wheelinls1]

The print out is a graph print, I can also do a line print which includes all logged data including barometric correction, its a couple of pages of data though so not as easy to read. The correction SAE J1349 also limits correction to within limits but I cannot recall exactly what they are, it won't accept intake air temps over 40 degrees C amongst other things. I can put up the data sheets if you would like, every dyno run saved stores all the information.
We did do YankeeDaves car and got gains around 8%-10% from stock with an increase in torque at lower speeds. I am still waiting on some info from Diablosport for YankeeDave. It would appear as though Jeep have tuned the engine quite well as is often the case when an engine is an outgoing model, not much left in reserve.

Joel

[AussieCJ7]

4wheelinls1

The real challenge is what can you do with OBD1 systems pre 96/97

[4Wheelinls1]

I received some feedback from the customer with the TJ tuned on 98 octane, the vehicle is returning 50-70 klms more per tank with noticable increased torque and transmission shift quality.
I was also surprised by the power of the V6 JK, eveyone seems to be complaining about them but I though the 115 rwkW we got was actuallly pretty good, the gains in power were not huge as is often the case with the last model engine in a series, the manufacturers tend to milk it for all they are worth. I have to get in touch with yankeedave to remove a Cat code, I'm hoping he'll have some economy results.

Cheers

Joel

[Banshee]

I think the reason for the complaints, is not the lack of power or torque per se, but the fact that it seems to lack it due to, (in my case at least), the abominable 3.21:1 diff ratio.

I've had my manual V6 for over a year & still stall it on hills. Compared to my TJ that I don't think I ever stalled. The only way to avoid stalling at least occasionally is to get the revs well up & slip the clutch if you are starting on any significant grade, and I don't usually do that. I slip it as little as possible, and hence stall the bastard!