Throttle Lag and Heel/Toe

[jwagner]

I've got a new 2.5L 6 speed that's gonna see some track use. I'm coming from a 2007 MX-5. After adding a gas pedal that I can hit with my heel without twisting my leg unnaturally, I still am having a hard time matching revs during downshifts due to the slow throttle response. I've got to hit the gas and hold it to get the revs up to where they need to be. It's not a drive-by-wire thing since my MX-5 was also drive-by-wire and the revs were there almost instantly after a throttle blip. I've heard it was a deliberate design feature to improve fuel economy. Has anyone else run into this? Found a cure? I'm thinking an ECU reprogram might do it, but I hate to drop that much money on the re-flash without doing the exhaust and intake and suddenly I'm dropping lots of money. My plan was to leave the car in a stock class anyway and I'm out of points, so maybe I just need to put up with it the way it is. The first track day is weekend after next so maybe I'll be able to figure it out on track.

Ideas appreciated.
Jim

 

[Mazda233]

I have an 08 2.0 that I purchased new, same problem. First tried a Sprint Booster which helped and then removed that and had Dynotronics do a retune. About a 75 percent improvement. I also have a 2012 Mazda 2 which is far worse than the 3 ever was, downright dangerous. I also have the same problem with mazdas pedal placement, if you search the 2 forum you can view photos of my pedal mods, these are early photos, I am still trimming and spacing to get them just right, will post updated photos when finished. Zoom Zoom my butt, what good is a drivers car with poorly spaced pedals and no throttle response.

 

[jwagner]

Looking at the pedal pics, you must roll your foot onto the gas. I actually swing my heel to the right and pop the gas with my heel so I had to extend the gas pedal down. Used a cheap SPARCO pedal set and it worked pretty well. I think the 3 will be a one season car (and long term DD) while I sell my MX-5 and look for a new one, so there probably won't be an ECU tune. It is tempting, though. We autocrossed the car last weekend and were surprised by how well it did with only a rear sway, alignment, tires and wheels. Makes me wonder what a full STF build would do.

Back on topic, it would be really nice if Mazda put a "Sport Mode" button on the car like the Mini has, or some magic "easter-egg" to fix throttle response. I suppose that's a bit much to ask for on an econobox type car.

 

[turbine50]

I installed a set of these and they work great. http://www.srpracing.com/cat_mazda_3_mazdaspeed_3.cfm

 

[jwagner]

I installed a Sparco Race gas pedal. Cheap but it gets the job done. Had to space it off about 3/16" on the bottom to clear the carpet and I also bent the bottom right side of the pedal up a big for an easier target. http://www.sparcousa.com/product/race-0

T50 - You've got a speed3, right? I wonder if the ECU thottle tuning is different? The lag between throttle blip and RPM is pretty slow. Actually a blip doesn't move the tach - you've got to hit it and hold it a bit. We run Monday and it's gonna be interesting. I can't hear the car in traffic even on the street much less surrounded by a bunch of noisy track cars, and since I used my available stock class points on a rear sway and 8" wheels, I can't put a muffler or muffler delete on. Engine RPM is inaudible even on the street so it's really hard to rev match on downshifts. Even so, It's gonna be fun to see if this thing will run with the stock NA/NB Meeyottrs that make up most of the class.

 

[turbine50]

It's a regular 2.5 with 2013 Speed wheels.

I've driven a 2012 and 2013 Speed and the throttle lag is about the same as mine. We could always spend $300 and see if this works- http://www.twmperformance.com/pedalbox/mazda-pedalbox.htm

 

[jwagner]

I've driven a 2012 and 2013 Speed and the throttle lag is about the same as mine. We could always spend $300 and see if this works- http://www.twmperformance.com/pedalbox/mazda-pedalbox.htm

I'm pretty sure that before I did that I'd try a ECU tune, which I'm pretty sure can fix the lag and would provide some added power. (but then I'd need an intake and exhaust...) Either way, it would take me out of stock classing.

Ran a Time Trials type of event today and the lag was manageable once you figured it out since the braking zones are long enough to get the revs up where they need to be. Turns out my lack of engine sound (stock muffler) to know where the revs are was a much bigger issue, especially in traffic.

 

[turbine50]

I had a chance to get some track time. First, my friend who is a professional racing driver (currently IMSA Porsche GT3's) took two laps driving it and he did't mention anything about lag. I drove alone in the car for two additional stints of about 5 or 6 laps each and it didn't even cross my mind. Save your money. The Corksport intake sounds awesome so buy one of those instead. I'm also running a Racing Beat exhaust. Together they enhance the power significantly. My friend commented that he was surprised at the power for a non-speed 3.

http://youtu.be/6VFo2o-j3i4








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