13' 3i 2.0l Skyactive turbo?

[DarkRyder]

is it possible to turbo a skyactiv motor w/ low boost? around 5psi would be optimal for me. Does anyone know if someone is trying this or have succeeded in turboing a skyactiv?

 

[DarkRyder]

i'm researching a way to turbo a skyactive. i have several parts picked out that may work. does anyone know how to lower the compression using the VVT built in the motor? and does pushing more air into the motor raise the compression? not sure if it does or not, if someone can point me in the right direction i'd appreciate it.

 

[concealer404]

I uhh.....


I'd suggest not boosting your car.

 

[DarkRyder]

the compression on the skyactives were originally 14:1 in japan, and they lowered it to 12:1 when they brought it to the us. that gives me a little headroom i think.

 

[mndsm]

Considering typical turbo compression ratios on ACTUAL turbo motors is usually 8.5 or LESS..... probably a bad idea. The ms3 and diesels being notable exceptions.

 

[concealer404]

the compression on the skyactives were originally 14:1 in japan, and they lowered it to 12:1 when they brought it to the us. that gives me a little headroom i think.

The compression doesn't really have much to do with my advice, though.

You have lots and lots and lots and lots of reading to do before you attempt to turbocharge a car, let alone a brand new one.

 

[DarkRyder]

i have turbo's 2 of my previous mustangs, and it was pretty straight forward, my last mazda would have been really easy to turbo. This mazda well.... its a whole different issue. i might have to wait till a turbo skyactiv motor is released and see how it comes from the factory and how its rated before i undertake such a task. I appreciate the help guys thanks.

 

[Suddueth13]

Same process as any other vehicle except proper tuning is going to be much much more important. Ignition timing will have to be perfect or conservative. Look at what the Toyobaru guys are doig with the triplets with turbos and superchargers. They run 12:1 compression as well.

And just for the record, most modern turbo cars run about 10:1 compression

 

[flatlander937]

With the Skyactive motors being direct injection, they can usually get away with more compression than a normal motor. You need to find a way to tune the fuel injection timing because the only reason direct injection is efficient as it is... is because it squirts the fuel into the chamber at the very last second before it is supposed to ignite. The reason why high compression and boost normally = boom is because the fuel is injected with the air and the fuel pre-ignites(detonation) and you hole your pistons if you're unlucky.

If you can't find an aftermarket fuel controller that is capable of tuning the direct injection fuel timing then you might as well not even bother unless you rebuild the motor.

 

[Suddueth13]

Even low compression turbo setups can detonate without proper tuning. Direct injection helps because you're allotted more saturated fuel mixture which can allow you to run more aggressive ignition timing. Bumping the compression higher means the ignition has to be a lot more accurate or needs to be conservative which won't yield as much power. Too aggressive ignition timing causes hotter cylinder temperatures which is where detonation comes from. Same thing with runnin to lean of an AFR.

 

[color0]

Even low compression turbo setups can detonate without proper tuning. Direct injection helps because you're allotted more saturated fuel mixture which can allow you to run more aggressive ignition timing. Bumping the compression higher means the ignition has to be a lot more accurate or needs to be conservative which won't yield as much power. Too aggressive ignition timing causes hotter cylinder temperatures which is where detonation comes from. Same thing with runnin to lean of an AFR.

The other thing to consider is that the Skyactiv injectors fire twice before the spark, and this is not something that any off-the-shelf fuel computer is able to tune. The most straightforward way of doing it is probably going to involve tapping the intake manifold and running an extra injector rail to an AEM FIC. Then you have to somehow 1) fool the MAF into thinking that nothing is wrong and 2) maintain conservative enough AFR's through the downpipe that the stock ECU doesn't freak out. If you get those two within range I think you could lightly boost the engine, but you're probably going to break conrods left and right.

 

[Suddueth13]

I wouldn't rely on piggybacks for something like this. Either tune it through the ECU or go full standalone. Fuel isn't the problem, that's easily managed. Setting and maintaining proper ignition timing will be the key.

 

[amx002]

Skyactive using retard intake valve close to reduce pumping loss. This also reduce Absolute CR. You can reduce Absolute CR by just retard it more.

The more you retard intake valve close, the more you increase expansion ration. Hence, improve fuel efficiency. However, doing so need to reflash your ECU firmware with new VVT table. And Mazda ECUs are encrypted. Even in Mazda 2, no one can break its code yet.

Even you could do all that. The more you pushing the limit by advance ignition timing and retard intake valve close, It could lead to destructive of your entire intake system by backfire. And inadequate retard valve close would lead to detonation inside the combustion chamber.

Is it worth the risk? I don't know. It's depend on your point of view.