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Turbo for the 2.3 6i

107156 Views 163 Replies 64 Participants Last post by  RiveraJ
This will be an evolving thread, but should provide enough info that we won't have a new thread every other day asking the same questions. Please bare in mind that the info provided is based solely on my experience and opinion. Please take the info i have and use it as you will, discuss the project with your local shop/tuner/dad/brother and move forward from there. Anyone with more info please feel free to give input, but i will be cleaning this thread up as it goes, so please don't bitch.

Q: What are my options for turbo'ing my 6i?

A: The options vary currenlty. there are 5 standard answers, most can be googled for more info
1) ]HiBoost (out of business, but used kits floating around)
2) F2 (never officially release, check with GP-Werks for more info)
3) HASS (via (not produced, but at least 2 kits floating around)
4) built using Mazdaspeed6 parts
5) depending on where you are, a TRUST (Greddy) kit is available, though tuning has yet to work in the states, as well as fitment issues with LHD models.

Q: Do I need to build the engine? what boost can i run "safely"?

A: The stock block has been pretty good on about 8psi on pump gas. Anything more than that the bottom end should be addressed. solid tuning and race fuel can up that #, but people have popped engines above 8psi.

Q: What about the tranny, i have an ____ (insert MTX or ATX)?

A: both tansmissions will be fine.
1- The stock MTX has a tendancy to sheer 3rd gear at times (no specific power level, just some last and others don't)
2- Both 4 & 5spd ATX trans also work, though it's recommend to run 6psi on these setups. also, an additional trans cooler is essential as well for the atx.

Q: Can i make my own, i found a good kit on ebay?

A: sure, have fun, don't cry when it doesn't work right and cost more in the long run!

Q: How much can i expect to pay?

A: Quick answer is have $5k ready to spend, or don't think about it. Now, it depends on the kit obviously. F2's stage1 will be the lowest price KIT, and HASS ranges up to $4300 i believe. You can make your own Mazdaspeed'ish setup, but it is not a kit, so prices will vary and you'll need to find your own tuning solution. The install is amazingly easy in these cars, the install would range in the 5-8 hour range if you are looking at a shop. Most KITS will come with a tune to get you started, though it's recommended to to dyno tune your specific car, which is roughly a 2 hour job, though doesn't really need to be done ASAP.

Q: What else do i need to buy?

A: If it's a true kit, then nothing! There are items to make it better, make it last long and obviously make more power....but they aren't needed. Things i would recommend you have on our short list however, as they will aid with tuning and safety.
1- a WIDEBAND (no, the narrowband you saw on ebay won't work) Air/Fuel gauge, this is a must for tuning
2- spark plugs (i REALLY like the Autolite 103's, especially in the beginning while tuning. They are UBER cheap, and work well, easy to gap also)
.....that's it, for the long list i'd add:
3- oil temp OR pressure gauge (dont' see the need for both, and no your stock gauge doesn't do anything. this is only to see problems sooner, nothing else)
4- boost controller (DO NOT ADJUST BOOST!!) A boost controller will aid in how the boost comes on and levels off, feels much better. i suggest a manual controller in the engine bay that you CAN'T touch while driving)

.....There are other things, but they are not turbo related, they are performance related. (things like limited slips, clutch/fly, better rubber). you DO NOT need a turbo timer if you have any common sense, you can, but you are just spending money.

This is all the basic info on the setups that i could think of. For the most part, an 8psi intercooled kit on a STOCK 6i MTX in the 225whp range, the ATX (6psi) at just over 200whp. Power will be increased with an exhaust, which most have anyhow, but it's not needed to enjoy boosting.

notes for the ATX guys:

'03-'05 6i's with the 4spd have an off the shelf option to upgrade both their valvebodies and torque converter from, or whole tranny if you'd like. The valvbodies help out an amazing amount, and allow for a bit more boost if you want, the converter allows for a higher stall speed which is nice if you powerbrake often (the strip) and they can also remove the lock-up setup which can be a bitch when having fun on highway cruising.

'05+ 5spd ATX's have faster/tighter shifting out of the box, so that is a nice start. If valvebodies are something you want (as they can be improved quite a bit), has experience with them, though you need to remove yours and send it to them for the work.

Both models- please take a minute to understand how your ATX works, and then understand why i say you should always let your foot off the gas between WOT shifts. It is not something that will brake the tranny in one time, but please understand it's not recommended as the boost is still being applied while the tranny is trying to shift. Also, for the same reason, if you are cruising on the hwy while the converter is in lockup, DO NOT just slam it to the floor, it's not good for it either, a quick blip or downshift will safe a lot of trouble.

Now, i know of roughly 6 turbo'd 6i's that are (or have been) daily drivable, there are currently 4 on this forum actively i believe (as of 6/09). I would imagine all would attest that it's a friggin blast to drive, and the smile doesn't leave your face! The car is still pretty light at just over 3k, so the addition of 80-90WHP (about 60%) makes a huge difference in feel. But keep in mind that it costs roughly $5k on the low side for the setup, which is anywhere from 25-50% of what the car is worth, premium gas is required now, and it's hard to go back to stock if you think it's temporary. In the 4 years i've been turbo'd and talking to people about it, i've found that if your plan is more than 6 months (it's more like 3-4) out, then you won't get it. If you have 90% of the money in hand and are serious, go for it, but if not, there's not need for a billion questions that don't go anywhere, please just read what's on here already and enjoy the dream (it's cheaper!)

This link will always show you all the current topics for turbo's on the 6i's:

Turbo threads

here's a few vids that have been around forever, but if you are new you might like them.

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tuning is just about around the corner for the 2.3L. the hold up is the many different crank triggers that was used in the 2.3L for the 6, so code has to be done for each.
will parts such as intake manifold and exhaust manifold from a speed 6 fit a NA 6
the manifold, turbo and downpipe will fit.

the intake manifold may fit, but things may be in the way since the speed 6 TB sits quite a bit lower than the 6i
also, since i posted about it early in this thread, i post a mini update. my 6i tuning solution is a couple weeks away. the ecu for the test car is at my house, but i wont be home till the second to link up with the test car owner and play with the tuning.
Give me an hour or so. I have it iirc from when i was doing the tuner for the 6i. Whats ur email?
Build your 6i. You will have the potential of making more power than the speeds. And it will be a built not brought car. Boost what you have. Hit up up Mfactory for one of their G-series forged LSDs put that in you mtx.

Everyone will say its cheaper to get a speed. But its really not. Just food for thought.
Boost is just a reference and does not dictate power potential. Airflow...better know as CFMs is what dictates actual power making for the most part.

8psi from a big borg warner turbo will make shit ton of more powr than say 8psi from a K04.
Money is what stops everyone from doing something they want in most cases. big turbo and intercooler only produce and cool the air takes an engine and tuning of that engine to produce the actual power.

...then there's the whole, power getting to the ground thing, so trans comes into play as well
Wow...didn't get an alert for that last post you just answered Tea. But I agree 100%. Tuning is huge. And I get upset when people try to run power adders without some form of tuning. Can it work? At times...Sure. But not optimally.

Do it right the first time or not at all is what I usually say.
I have tuning available for the 6i's. As I have said.
You don't need to route the the BPV/BOV back to the intake manifold. People typically do this on draw thru MAF setups where venting to atmosphere would cause a temporary rich condition after a shift because metered air is vented off and lost.

There are two ways to fix this:

1. Run a blow thru MAF setup and have the BOV/BPV plumbed prior to MAF so no metered air is lost. Blowthru setups are far more accurate in terms of air volume and air temperature metering accuracy on a boosted app. Some people go draw thru simply because they are in fear of saturating the MAF (flowing more than the MAF can meter). But blowthru is the best in terms of accuracy. There are also ways to keep the MAF from saturating and increasing range.

2. Tuning TIP-IN enrichment

If I were you I would not waste time on a K04 or the stock speed manifold. Get an aftermarket speed manifold with a T3 flange. Why? Because it opens up numerous turbo options. Just my educated opinion

The speed6 intake manifold will not bolt up to your regular 2.3L...... If you really insist on running recirc for the BPV/BOV and/or draw thru MAF setup just route it back to the turbo inlet/intake between the compressor housing and MAF. Just be sure to have about 6" from the port and the MAF to help reduce or eliminate reverberations

Any questions or further help don't hesitate to hit me up here or on my tuning page in my Sig.
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Also....what are your power goals? Built engine or keeping it stock?
Actually yes I have done it before...on numerous platforms. As I don't only deal with Mazdas. On stock Ecu's, standalones, and piggybacks. Hence my semi detailed description of how to do it and knowledge of which route is more accurate. This is not my first go around with this stuff. It does not need to be recirculated if you tune the proper tables. Or in mazdaedits case....find them or make them.


Speed density definitely has its adavantages. For 8psi that you wish to run it'd be fairly simple. But as unsaid...I wouldn't waste time messing with the K04 for 8psi. It doesn't flow much.
And that pic is a good clear example of the recirculation of what I was saying. Good add
Must get a lot of cali Mazda 6 cars then....because those are the only 2.3L Mazda 6's that came with Denso ECU's.

I don't have time to argue with you. OP, I'm around if you need me.
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