Tune development

VersaTuner for Mazda SkyActiv Diesel powered vehicles
Jpk
Posts: 27
Joined: December 5th, 2019, 6:10 pm

Re: Tune development

Post by Jpk »

I switched back to the beta tune and have been enjoying it. However tried to do some more logs for virtual Dyno but in 4th gear this time and actually hit the egt limit just after I'd let off the accelerator on my second pull, car juddered as it temporarily cut the power and then drove perfectly normal again for the last 25 miles home. To be honest it's not how hard I'd normally drive my car, but I hadn't exactly thrashed it either so a little disappointing.I'd gone wide open throttle from around 1000rpm to over 4000rpm so was doing over 90mph when it happened. Done logs today on some nice winding country roads today en route to picking my Xmas tree up to check the temps on a regular driveand had no issues, driven it as hard as I normally would, but not had time to pour over the log.
mituc
VersaTuner guru
Posts: 1039
Joined: December 17th, 2011, 2:47 pm
Location: Iasi/Romania

Re: Tune development

Post by mituc »

It would be very useful to present some logs for this kind of events. This is what is needed by the people who work on developing these tunes.
2008 Cosmic Blue Mazda 3MPS
Built engine + WMI + GTX3071, ~476WHP @31-32PSI
2008 Icy Blue Mazda CX7
Stock engine and exhaust (YES!!), JBR3" + GTX2867 gen2 + Autotech HPFP, self-tuned to 320-ish BHP
Jpk
Posts: 27
Joined: December 5th, 2019, 6:10 pm

Re: Tune development

Post by Jpk »

Emailed the log over. Temps didn't even get close to that on my subsequent country drive, maxed out at around 1200f so will keep running the tune and see how it performs for me on my normal commutes and nipping about. Wanna get out on some more twisty roads anyway as I installed the corksport solid shifter bushings last night so wanna see how my gear changes now feel.
Jpk
Posts: 27
Joined: December 5th, 2019, 6:10 pm

Re: Tune development

Post by Jpk »

Is anyone else running this tune and got some feedback or reviews, seems to have gone all quiet again!
mk_
Posts: 4
Joined: October 25th, 2020, 11:23 pm

Re: Tune development

Post by mk_ »

I tried it out. It's a bit less smooth than 175 tune, but that's not a deal breaker for me.
I compared data from this beta tune and 175 tune, using virtual dyno, and with new tune I get around 210HP (crank) and 480Nm, and you definitely feel it.
But during one uphill overtake, in 3rd gear, full throttle, I experienced power cutoff. Unfortunately I don't have log for this, only relevant information is that outside temperature was 10C.

I found this old post on other forum, it looks like other tuners were aware of this problem even in 2015. It's possible that this problem can't be solved just with tuning, hardware upgrades are required.
https://www.mazda3revolution.com/thread ... st-1460169

So for now, I'm going back to 175 tune, for reliability reasons.

I would like to see new tune with a bit smaller power levels, about 200HP and 450Nm and stock EGT limits. With this beta tune I was getting EGT temps above 840C, while stock limit should be 790C.
Maybe stock intercooler can handle these smaller limits.

Image
Jpk
Posts: 27
Joined: December 5th, 2019, 6:10 pm

Re: Tune development

Post by Jpk »

Sounds like the power cutoff I had, pretty certain you must've exceeded the egt limit on the tune as I did. I didn't get close to the limit on subsequent spirited drives though, only only long pulls at full throttle. Could you please share the custom car data you've put in virtual Dyno as I can't find the proper drag coefficient, gear ratios, final gear ratio etc anywhere for out diesel's. Been comparing tunes on there but with incorrect data so can see bhp changes but not the true bhp 😟
Post Reply