Hello All,
I am new to the mazda 3 and am looking to possibly buy one as a family car/ playtoy. I am an automotive technology guy who loves the engineering in automobiles and I had a few random questions about the new 2012 mazda 3 with the 2.0 skyactiv engine.

- Does the new skyactiv 2 liter engine use variable intake runner length?

- What is the stock throttle body size? Also, what type of throttle control is used?

- Has anyone dynoed one of the new 2012's yet and have a postable sheet? Just curious!

Thank you for your time!
Matthew

 

like all published numbers, it's good to reduce 10-15% due to powertrain loss because the manufactor numbers are taken at the flywheel.

I'm not trying to be an ***, but what's the point of knowing the throttle body diameter and whether the intake or exhaust valves are variable? It's likely the throttle is by wire like the other Mazdas.

 

I have access to a very large machine shop. In my free time I toy with intake manifold design. I'm by no means an expert, but I do like toying different runner lengths, taper percentages, and plenum volumes.

Matthew

 

I did a little searching and didn't find any info, likely because the engine design is so new.

but...like most naturally aspirated cars, it's likely the intake valves are variable. unlike desiels that vary the exhaust valves to prevent the "wonderful" thing known as knock.

 

I could be wrong but I don't think you're asking about variable valve TIMING (which it does have on both intake and exhaust), but rather variable LENGTH of the runners on the intake manifold. I can't say for sure but I'm am pretty certain that this is not a feature on the Sky-G motor. I have taken the 6-Speed AT i Touring model for a test drive and I will say that the drive train is very smooth. The motor is quiet even under load and at the top of the rev range. It's not a speed demon, but not a slouch either. The transmission shifts quickly and smoothly, overall I was very impressed. My wife and I have one on order, we've always liked the look of the 3's but were never impressed with their fuel efficiency, but that's all changed now! Not sure if this helps you out or not.

 

As far as modifications go, you should trust that the 100's of engineers at Mazda did all that should be done to the Skyactiv. It has a very specific purpose and does it very well. Any intake or any other mods for that matter would most likely be counter productive.