Hello all!

I'm new to the crowd and would like to say thanks for having me. I'm facing a dilemma in choice of vehicle and would like to run it by those who know vastly more about the Mazda 3 than I do.

This upcoming week I'm about to pick up either a 2010 Mazda 3 or a 2012 Mazda 3. Naturally my first instinct is to go with the 2012, however; Both have the same number of miles (+-1000) and they are two different packages.

The 2010, upon a VIN check, reads this:
Engine type: 2.5L L4 DOHC 16V
Trim level: s Sport 4-Door

The 2012 comes up with:
Trim level: i Touring 4-Door

The 2012 has the fancy blue cover on the engine which I've found means it's the SkyActiv engine (please correct me if I'm wrong). The 2010 does NOT have that. From what I understand, SkyActiv is a set of mods Mazda engineered into the engine to increase compression and thereby increase fuel efficiency, though probably more scientifically than what I just described here. Therefore, if I ever plan on doing anything to the engine I'll be extremely limited and will have to look elsewhere for more power such as lighter wheels and exhaust work. What I DON'T know is whether the non-SkyActiv engine will lend itself to more mods or not, or whether it's even worth it if there's features or changes to the 2012 over the 2010 that would merit one over the other such as interior changes, though at first glance at the photos I see no differences there.

What do you guys thing? What would you do?

 

the Skyactiv engine is only a 2.0 ltr engine. It will be slower & have less power.

As I'm overseas I don't know the spec levels in your country. 2012 will be the facelift model. You will need to find the spec sheet for each model your looking at.

 

The skyactive has electronic "everything", no throttle cable. It has an unusually high compression ratio. And it burns very lean when you're foot's off the throttle. It's very efficient, i'd say even more efficient than the sticker suggests (my 2014 is advertised to get 29city/41hwy, and with only a bit of effort I'm getting more like 33city/43hwy). It tops out at 155hp, but the engine feels 'winded' at anything above 5k rpm. It feels strong for a passenger car, but it's not a sports car.

The 2.5L should have more power. But noticeably less fuel economy. I know less about this engine/drivetrain. But I think it has a fairly normal compression ratio, so you could probably put a turbo on it for substantially more power. I don't know how pricey that would get though.

The skyactiv engine would probably be very friendly to intake/exhaust mods that allow it to breath more air (CAI,TB,manifold,header,cat,cat-back). The variable valve timing should allow it to pull with authority to the redline (6300) if the engine could breath better. If i had to guess, I'd say you could get it to about 175-ish hp if you did the whole intake-exhaust path. I would NOT turbocharge the skyactiv though, it's got a very high compression ratio, and if you add boost, it can't end well. Personally, I think 1st gear in the skyactiv drive train is a little tall. With 6 gears, they really could have made 1st gear a bit more aggressively low in gear ratio. But without limited slip differential, I suppose it would only empower you to spin your tires more, rather than really go faster.

Go sit in them! You'll know then

 

Both cars will have fly by wire throttle. The skyactiv engine is built for low emissions & maximum fuel economy.

 

Skyactive 2.0L: The U.S. version with a 13.0:1 compression ratio produces 155 hp (116 kW) at 6000 rpm and 150 lb·ft (200 N·m) of torque at 4000 rpm.

2.5L : North American markets for MY2009, the 2.5L L5-VE is an updated, bored and stroked version of the L3-VE 2.3L. The 2.5L (2,488 cc (151.8 cu in)) L5 engine has an 89.0 mm (3.50 in) bore and a 100.0 mm (3.94 in) stroke, with a compression ratio of 9.7:1. The standard crankshaft is forged-steel with eight counterweights. 170 bhp (130 kW) at its 6000 rpm redline (168 hp (125 kW) in PZEV trim). Certain versions are rated at 175 hp (130 kW) at 6000 rpm with 172 lb·ft (233 N·m) of torque at 4500 rpm.

 

I realize I'm resurrecting a cold thread, but so what? Based upon UYN's specs the 2.5L engine is an oversquare design meaning that it has more stroke than bore. Traditionally, oversquare engines are better highway cars because they have an abundance of torque right in the RPM band that most folks use when driving on the highway, about 3,000 RPM.

I know that my 2010 2.5L 6-speed MTX Hatch can easily make passing moves by simply goosing the throttle a bit, no downshifting needed. I really like that, makes for a more relaxed, less frenetic ride. The one thing I'd like to do is remove the 118 MPH electronic governor, anyone have any clue as to how that can be accomplished?

And seeing that this engine has a forged crank was a real bonus, most cars have cast cranks which are cheaper/easier to manufacture but not nearly as strong. Everything I read about this engine indicates that it is a very stout unit indeed. With regular maintenance, and if you don't drive like a dipsh!t, you should be able to get 200 - 300k miles out of them pretty easily. My car has 85K mi. and I truly hope to achieve 200K+ from it.

My car seems very "tight", no squeaks and rattles at all except for the damned annoying seatbelt squeak that many complain about. However, the fix is pretty easy - saturate the area with silicon spray and it should go away.

I am *totally* digging my car - it has a very sleek body shape (virtually no wind noise at 85 mph), it handles fairly well except for a fair amount of understeer which I believe could be mitigated with a rear chassis brace and/or a thicker front sway bar, the interior is quite nice for an "economy" car, and the motor and tranny seem to be very robust and quite well-engineered.

There are numerous reasons why most of the car mags rate the 3 as the best of the econoboxes - and that's why I bought my car. It looks good, goes well, and is fairly economical to operate - ya gotta love that!!

-CD-