Bosswagon Ver 7.0 beta1

[rodslinger]

Boss Wagon Ver 7.0 beta1

A little Q&A below.

• What it is? Turbocharged Mazda5, automatic transmission

• Why do it? s*** man, why not. Actually this was my wife's daily driver. I had a 2006 Sentra Spec-V until about four months ago. I sold it and bought a 2013 Chevy Sonic Sedan w/ 1.4 turbo. I chip'd it and the wife promptly decided she liked it more than the 5. I couldn't let her have a faster vehicle than me so I decided a turbo was cheaper than trading this in on a Mazdaspeed 3. More practical also.

• Why is it called Boss Wagon Ver 7.0 beta 1? You may recall Car and Driver took a wrecked Mazdaspeed3 and transplanted the drivetrain into a 5 (Bosswagon 6). Well it didn't work out that great. Electronics issues, tuning issues, etc... It never ended up being a streetable vehicle. I wanted to create a version of the 5 that Mazda SHOULD have created. A little extra power, reliable and most of all FUN. I need to be able to load the kids up and take a road trip but if I'm in a hurry to get somewhere this thing needs to MOVE.

• Parts used? Base Mazda3 turbo kit from Tripoint Engineering, AEM Failsafe wideband A/F gauge and a spark plug anti-fouler for rear O2 sensor

• Special modifications? Mimimal. Intake tube supplied from Tripoint is much larger than factory tube which throws off MAF readings a LOT. Created an insert at MAF sensor to reduce ID of intake tube to match factory diameter to eliminate error codes. Will outline that also. Transmission dipstick tube interferes with the turbo inlet elbow. You have to use a little grunt and bend the dipstick tube toward the firewall and to the right a little. Also trim off about 1" from the elbow so it mounts closer to the turbo.

• Special notes for those with 2007 and later FEDERAL emission vehicles. The AEM F/IC cannot skew the O2 sensor readings to tweak fuel trims in closed loop operation. It looks like I'm able to force the ECU into open loop operation under partial throttle loads and light boost via MAF skewing. We are still working on a permanent solution but for now this seems to work OK.

• Driveability Questions? Cold start, idle and low speed operation is as it was before the kit. Fuel economy has not dropped if I stay out fo the boost. If I keep my foot in it well that is a different story. Last fillup was 19.8mpg. That was mixed city/highway driving. Previous fillup before turbo was in the 17mpg range with 100% in town stop and go driving. It will take a few more fillups to see how things skew.

• Performance? Pulls nice especially in city driving. 2nd and 3rd gear around town allows this thing to pull away from traffic easily. No more matting the pedal to climb a hill or struggling to gain speed for a merge. This thing moves. Highway driving is very nice also. The transmission rarely downshifts when climbing a grade or speeding up a little. Plenty of torque. Drop it to 4th and it'll go from 60 to 80 for passing in a blink.

Picture of installed kit

Picture of intake tube modification below. The intake tube from Tripoint had an inner diameter almost exactly 3". The factory MAF tube inner diameter for the 5 is about 2.43". The reduction in airspeed across the MAF with the larger tube made idle erratic and low speed throttle tip in a little rough. Scaling the MAF signal via the F/IC didn't help with this much and never would get rid of the MAF error codes. I purchased some 2.48" inside diameter aluminum tubing from McMaster Carr and some PTFE gaskets and made a liner for the Tripoint MAF tube. I used an o-ring at the MAF openeing to prevent air leakage between the inner and outer tube where the MAF sensor installs. Now the MAF scaling at idle and low speed is where the ECU expects it and eliminated ALL cold start and low speed driveability issues. Feels stock when starting it up and driving under boost.

Picture of AEM wideband gauge. I placed it in the coin pocket to the lower left of the steering column. It is visible in my driving position and this gauge allows the display to flash in the event the A/F ratio goes outside a boundary set in the programming. If it goes above 12.8:1 under boost it gets your attention pretty good and lets me know to get out of it.

Short test drive video. We are still working on the tune and have limited control over getting a rich mixture in light throttle loads. The O2 sensor on these 07+ Federal cars can't be fooled like earlier models. I'll get some WOT runs when I can see a safe A/F mixture. Even at 3 to 5lbs it pulls much better.

 

[rodslinger]

Will post pictures for specific questions here.

 

[rodslinger]

Actually I just filled up with gas this morning. Ended up at 22.3mpg on that tank. Not bad considering it has been very cold the past few days, have been driving mostly loaded with family and gifts.

 

[Silentnoise713]

Look forward to more pics and specs.

Would like to see more pics of the manifold and clearance relative to hood and firewall.

 

[rodslinger]

Clearance wasn't a problem. I've owned a 2003 and a 2010 Mazda3 also. The hood on the 5 seems to have a wee bit more clearnace between the top of the motor and the underside of the hood. The clearance between the rear of the motor and the firewall appear almost identical which would make sense that they are basically the same chassis.

The cowl does appear to come forward a little more than the 3 so getting the OEM manifold out and turbo in did take a different process to install. Tripoint recommends just unbolting the lower rear torque mount and rotating the motor forward. This will allow clearance to remove the factory manfiold. This didn't work on the 5. I actually unbolted and removed the passenger side engine mount while supporting the engine from below with a wooden block on a jack. I lowered the motor making sure not to tweak any wiring harnesses or lines and gained a LOT more room to work on the exhaust side of things.

 

[rodslinger]

Took it for another short drive. Running up the revs under partial throttle, no boost to make sure the ECU goes into open loop. Did a short pull in 2nd from about 40 to 60mph. Still filthy rich at WOT. In the 9:1 to 10:1 range. Safe but probably leaving a lot of power on the table.

 

[pkthomas]

Very nice. I would like to do this to my 2010 sport manual and put a 6 speed manual from a speed3.

 

[rodslinger]

I've been datalogging it quite a bit today. I still need to lean it out under open loop. It is still pig rich and leaving quite a bit of power on the table. I saw a few spots hit 8:1 and misfired due to being too rich. Big 'ol puff of black fuel cloud out the back. I'll address these spots as I can but would rather be way too rich and lean it out gradually to get to the sweet spot than be too lean and melt it down.

I'm still on the stock exhaust also and I think it is choking the car in the upper rpm range. It appears that boost is actually dropping off past about 5.5k rpms. I'll see it peak at about 8.2psi in the 4500 to 5500 range and knocks back down to the 6.8 to 7.5psi range past that. Will put another 1/2 turn on the wastegate preload just to make sure. I won't be messing with this anymore until the weekend. Back to work and life again....

 

[chief_wiggum]

This is good stuff, very good stuff.

 

[twintrbo]

Subscribed! I'm dying to do this myself, surprised there are so many tuning issues, I thought the tri point was plug n play.

 

[phunky.buddha]

Sweet! So you basically did your own MAF hack (that's what the Nissan guys call it), or actually reverse MAF hack...

When I was replacing my clutch, it looked like there would be plenty of room to pull the manifold out the bottom with the intermediate shaft removed. What are you using for boost control? Knock sensor? Is the A/F gauge based on the stock O2 sensor or a wideband? If wideband, does it replace the stock sensor? Am I ignorant in assuming the stock sensor is narrowband and it's actually wideband?

 

[rodslinger]

I didn't know anyone else was altering the MAF tube diameters like that. I only knew I had to do something. I thought that was a better solution than just putting a dent in the side of the tube and not as permanent. I think the MAF tube on the 3 is closer to 2.65" to 2.74" depending on year and model so it probably isn't throwing codes on those. From that point of view the Tripoint kit is plug and play. They just didn't anticipate anyone putting this on a 5 so that much of a diameter change made a pretty big difference.

I don't think that manifold would have come out the bottom even with the axle out. It is pretty bulky. The new manifold with the turbo bolted on takes up even more space.

Boost is strictly controlled with an external wastegate on the turbo. Spring loaded and set for about 7.5psi.

The A/F gauge is running off an extra wideband sensor in the exhaust downpipe about 3" from the factory upstream sensor. The factory upstream sensor IS a wideband type but you cannot use it for a wideband gauge. It does not output voltage like a normal wideband sensor. It outputs current. At 14.7 stoic it delivers 0 current. When lean it sends positive current in mA. When rich is sends negative current in mA and there are two current control leads on the sensor. I like this gauge/sensor combo as it does boost and A/F on the same gauge. The outer segments can be programmed to change colors based on parameter and the center display can be set to flash if anything goes outside a set range also. The gauge has a USB cable coming off it to connect to a laptop and pull datalog or change settings.

 

[phunky.buddha]

Quite a few people tuning MAF cars go cheap and "MAF hack" by increasing the diameter of the tube the MAF sensor sits in- it's an imprecise science, but the basic gist of it is that you can increase your injector size by approximately the same percentage that you increase the area of the MAF cross section. Your MAF still tells your ECU that you're seeing the "old" amount of air, but since you're passing more air, you can spray proportionately more fuel and increase your power levels- all without screwing around with your ECU program. There is some loss in the conversion because of tube flow characteristics (injectors have to go larger at a slightly higher % than the tube size) but it works for quite a few people. It's an easy way to add boost (and larger injectors) to a Nissan without actually having to tune the ECU much.

Thanks for the note on the manifold. Might have to make my own, slightly smaller.

Normal kit comes with an external wastegate? What size/brand?

Good to know about the O2 sensor- I had no idea!

 

[rodslinger]

Fuel Economy Update

Well I took it on a road trip. Quite a long one actually. I needed to make some site visits for work and I was comfortable enough with the tune and assembly that I would have no issues. This week I drove from Atlanta to Columbia, SC, then to Charlotte, then to Knoxville, TN, on to Nashville, down to Birmingham, continuing to Mobile, AL and back to Atlanta. Somewhat of a "tour of the south".

I put nearly 1700 miles on it this week and averaged 26.4mpg overall. Almost 95% interstate travel ranging from 65 to 75mph. A few passing blasts from 60 to 85+ but not many. I'm satisfied with that. Just drove normal overall.

Very happy with the highway manners on this thing. Doesn't unlock the torque converter or downshift anywhere near as much when climbing a grade or just speeding up a smidge to adjust for traffic. I really feel like when the tune is perfected I could actually get better highway fuel economy that I did before. The available torque just lets the engine pull up a grade and maintain speed VS the thing always having to downshift and rev to pull the weight.

Will get a few good vids of 0-80 runs and highway 50 to 80 pulls when everything is dialed in the rest of the way. I put a spark plug anti-fouler on the downstream sensor before departing and haven't gotten the catalyst efficieny code yet. The ECU still isn't reporting completed EVAP test even after nearly 1700 miles so not sure why the readiness state hasn't locked in yet. Only other issue I noted was I moved the ambient temperature sensor for the outside temp display a few inches when mounting the intercooler. I guess it is getting some recirculated air from the condensor/radiator where it is so it isn't reading accurate. It may show 75F sitting in traffic when it is 30F outside....

Just looking for an exhaust system to put on it and maybe help it breath a little.

 

[phunky.buddha]

Very nice! Plumb in a 3" from the downpipe back.

 

[foxhound1979]

Just looking for an exhaust system to put on it and maybe help it breath a little.

Speed3 catback ?

Just out of curiosity, how much did the whole project cost at this point ? I'd understand if you want not to give the info i'm just curious.

Great job and i'm subscribing !

 

[rodslinger]

Speed3 catback ?

Just out of curiosity, how much did the whole project cost at this point ? I'd understand if you want not to give the info i'm just curious.

Great job and i'm subscribing !

I am under the impression that the 3 exhaust has a different length at the tail end of the system and isn't a direct bolt in. I am fortunate to have an exhaust shop near me that can mandrel bend pipe. Will probably go visit them next week.

For cost I think about $4300 total. That was for the Tripoint kit, AEM Wideband Failsafe gauge, some new heater hose and vacuum line for rerouting some lines, aluminum tube and PTFE gaskets for MAF modification, stretch tape for wrapping the new wiring harness, fluids and a other misc hardware like hose clamps, vacuum tees, etc.. Nothing major. Hardware store stuff. Adding in the cost of the van, used Mazdaspeed wheels and the rear swaybar I think I am still at a lower cost than buying a Mazdaspeed 3. Of course it isn't as fast but it is WAY more practical.

I've done no tweaking or adjustments since my last update. Everything is working fine and am basically just driving it. I am working on something for it and will disclose it when finished and functional . Nothing radical but probably a method to make this install WAY easier for others.

 

[foxhound1979]

I am under the impression that the 3 exhaust has a different length at the tail end of the system and isn't a direct bolt in. I am fortunate to have an exhaust shop near me that can mandrel bend pipe. Will probably go visit them next week.

the speed3 line has to be custom made to fit, i'm getting one somewhere in april/may that has been custom made for the 5. Or something with a nice Vibrant muffler could be good, i hear good things about that brand.

Keep it up !

 

[Silentnoise713]

How's the car holding up? Any new updates and more importantly pics? Want to see more (of the install not the car, we know what the car looks like)!

 

[Rockin03mp5]

suprised i havent subbed to this yet...