[Cdn17Sport6MT]

I posted the following on the Mazda6club forum... but got no response. As the Mazda3 2.5 6MT has the same power, torque, and gearing as my Mazda6 (notwithstanding my 6 being a bit heavier) the question also is worthwhile to put to you folks.
TIA for any responses:

I have a '17 Sport, 6MT by way of transaxle. I intend to have an Orange Virus Tuning tune (for 87 octane) once my car has, oh, 10,000 miles. For now driving it in the city I am profoundly struck with the difference in torque/acceleration I notice between 1st gear and say 3rd gear. Especially with 1st being very, very low-geared. Lacklustre in 1st... totally fine (for me) in 3rd. Thinking out loud I wonder if the powertrain control module purposely trims back the responsiveness and torque in 1st gear.... notably so, and excessively so. I hear nothing but praise for the OVT changes, especially if the owner asks for a bottom-end torque enhancing tune versus a top end oriented tune. I wonder if OVT is just fixing the over-done trim-back for torque steer, stock? The high compression 2.5 liter long-stroke engine should have some bottom end grunt, no? Comments?

 

[Matt22]

I could be wrong but i believe the car is made for MPG not performance. also if you wanted more grunt you would have got an 92 octane tune with Tmap update.
But just for kicks i really think you should go to a mazda dealership, drive a stock 3 with the 2 litre and you will be pleasantly happy with your 2.5

 

[skyactiver]

The tuning maps between the Mazda 3 and 6 2.5L models are mostly the same. If you take them to a dyno, you will notice both cars have similar hp and tq curves. The Mazda 6 weighs a bit more, but not by much if you compare the Mazda 3 hatch with the Mazda 6 touring model, both 6 spd MT (130 lbs). Where they do differ the most is in the way they are geared. When considering the manual transmission versions, the Mazda 6 has a higher final drive ratio which may explain why the car feels more peppy. Considering that only the final drive gear is different, the 6 probably feels a bit more peppy in all gears, but you will notice mostly gears 1-3 on a daily basis. Here is the gearing according to Car and Driver's convenient website:

2017 Mazda 3 2.5 6spd manual:

First Gear Ratio 1): 3.70
Second Gear Ratio 1): 1.95
Third Gear Ratio 1): 1.30
Fourth Gear Ratio 1): 1.03
Fifth Gear Ratio 1): 0.84
Sixth Gear Ratio 1): 0.68

Final Drive Axle Ratio 1): 3.85



2017 Mazda 6 2.5 6 spd manual:

First Gear Ratio 1): 3.70
Second Gear Ratio 1): 1.95
Third Gear Ratio 1): 1.30
Fourth Gear Ratio 1): 1.03
Fifth Gear Ratio 1): 0.84
Sixth Gear Ratio 1): 0.68

Final Drive Axle Ratio 1): 4.11

OVT's throttle response add-on to the tune should make the 3 feel a lot more like the 6. With the power gained from the tune, it will also be faster, but I recommend at least 89 octane to make it worthwhile for the 2.5L (higher octane the better).

 

[Cdn17Sport6MT]

Thank you All for the useful and complete responses. Good info... didn't know about the final drive ratio differences. When I re-read my original post I realized that I was unclear with two items: i) I own a Mazda6 - 6MT... a 2017 Canadian "GX" version which is reasonably equivalent to the 2017 US Mazda6 "Sport"; I do not have a Mazda3; and ii) I have less than 10,000 miles on it thus far so I have never been at wide open throttle -WOT - nor have I been over 4500 rpm. After I have logged those miles I will go to the OVT tune... where I need to test and data-log at WOT and at higher revs. Good point re maybe going for a base tune on 89 octane... for a more pronounced effect from the tune.

Having said the above I will edit my original post to make it more clear.

My reason for posting here is that most of the articles I've read re the Mazda3 with the 2.5 and the 6MT... in fact for all of them - none criticized the first gear performance... at least none contrasted first gear perf. with the 3rd gear performance, saying that first felt weak compared to third. I feel this is the case with my Mazda6. I have some experience with my 1999 Camry... 5 MT - where with longer wheelbase FWD cars (the Camry is 3000 lbs.) - front traction is not so great. Of course tires matter... but generally longer wheelbase FWD vehicles have traction challenges. It is therefore possible that the factory tune diminishes first gear torque levels to mitigate against both poorer traction and potential torque-steer on my 6... and not so on the 3. Comments? Anyone find their 2.5 liter 3 - with 6MT 'kinda lousy in first gear? I find that i like the car better, sometimes... with traffic on my tail, starting off in second gear... to avert that very short distance travelled in first... and then the need and delay in acceleration, shifting from first to second... with the guy behind me (with an automatic) nearly ramming me from behind ?

 

[Cdn17Sport6MT]

Sorry... tried to edit my above first post to make it more ckear... but no dice. Would not let me. To be sure, then, I have a Mazda6... and am attempting to find out if you Mazda3 folk experience the same first gear "soft" performance. TIA ?.

 

[Midnightsky228]

I have the 3, 2017 2.5L manual, I actually find 1st gear gives a really good launch, I wouldn't want anymore power there. However, I haven't had a proper set of summer tires on this car yet so its possible with more grip a bit more power wouldn't be bad in 1st gear.

 

[Cdn17Sport6MT]

Latest Poster: thank you for your response. If you let the car only get to say 3200 rpm's before you shift from first to second... and you use say moderate throttle - do you notice any torque weakness in first.. whereaa not in higher gears? What I mean... is just in regular, commuting in traffic like driving... ?

 

[Midnightsky228]

Latest Poster: thank you for your response. If you let the car only get to say 3200 rpm's before you shift from first to second... and you use say moderate throttle - do you notice any torque weakness in first.. whereaa not in higher gears? What I mean... is just in regular, commuting in traffic like driving... ?

Never noticed anything like that no.