USDM GT86 with AVO Turbo!

[ecko04]

Originally Posted by nataku

That's a bit of a story that I'll share later. I didn't dyno today because of an overboosting issue. I'll share more later on.

Damn. I hope you caught it early, which I think you did. I saw your car parked. Keep me posted, your car is clean and definitely a sleeper.

[Sportsguy83]

Originally Posted by nataku

That's a bit of a story that I'll share later. I didn't dyno today because of an overboosting issue. I'll share more later on.

Hope the tune had overboost protection!!

[nataku]

So the overboosting issue was caused by the following broken hose:



This little bastard was hooked into the turbo directly. I can only assume it was responsible for feeding to the wastegate. Since it was broken right at the turbo this meant the air pressure never reached the gate and therefore never caused it to open.

My car built boost continuously. Toan @ptuning never let it get too dangerous but noticed there was an issue when I was making over 300 hp at around 5500 RPMs. He's going to send me the dyno plots for comical value.

Thankfully we caught this when we did. I learned a couple things here:

1. GET A @#$%ING BOOST GAUGE!! Even my "safe" 5 psi tune could have had catastrophic mechanical failures which very nearly lead to engine grenade. I would have known something was wrong if I had a boost gauge. I know this is obvious but I felt like reiterating the obvious since I didn't do the obvious...

2. This was the reason I "needed" a new clutch. I was making tremendous power and didn't even realize it. A stage 1 tune with the stock clutch might be just fine after all.

3. THIS ENGINE IS AMAZING. It put up with this unbelievable punishment without knocking or showing any signs that something was wrong. I was pushing 12+ psi on pump gas with no fueling system upgrades. I DO NOT recommend doing this permanently, but I must say I am thoroughly impressed and relieved that this wasn't a blown motor.

I'll post the dyno plot when PTuning sends it to me. I was on track to make nearly 330 whp lol. Don't know what the torque numbers were yet but boy was that a surprise....

[nataku]

Originally Posted by Sportsguy83

Hope the tune had overboost protection!!

There was a boost cutoff set at 11 psi, he's going to lower it. At any rate the cutoff wasn't working, possibly because of the issue with the hose, I'm not sure yet. I'm bringing the car back to them on Monday to verify everything. It's still safely driveable out of boost, assuming the issue wasn't fixed by them replacing that hose.

[ecko04]

Good job catching and fixing it!

I have overboost protection loaded into my tune. What gauge do you have? I would grab a FA20Club (P3 Cars) gauge. I can't speak highly enough of it. It monitors a crap ton of stuff and with an additional a sensor can also display oil pressure. I usually keep the display on AFR because my max boost is set on the gauge and if an overboost condition occurs the gauge will repeatedly flash.

Also my overboost protection in the tune is set to .25psi over the set pressure so even the slightest overboost will set off my protection layer.

[nataku]

Originally Posted by ecko04

Good job catching and fixing it!

I have overboost protection loaded into my tune. What gauge do you have? I would grab a FA20Club (P3 Cars) gauge. I can't speak highly enough of it. It monitors a crap ton of stuff and with an additional a sensor can also display oil pressure. I usually keep the display on AFR because my max boost is set on the gauge and if an overboost condition occurs the gauge will repeatedly flash.

Also my overboost protection in the tune is set to .25psi over the set pressure so even the slightest overboost will set off my protection layer.

Thanks for the recommendation. I mentioned that in my list of lessons because I do not have a boost gauge, hence the not following my own obvious advice.

Toan was saying I have a boost cutoff. I don't know if that is the same thing as overboost protection, but it sure sounds like the same thing.

At the moment I plan to pick up a cheap Android tablet and get the Torque app going. I saw it in a friend's car and it had AFR and Vacuum readings up, thought that was a pretty badass combo.

[ecko04]

Originally Posted by nataku

Thanks for the recommendation. I mentioned that in my list of lessons because I do not have a boost gauge, hence the not following my own obvious advice.

Toan was saying I have a boost cutoff. I don't know if that is the same thing as overboost protection, but it sure sounds like the same thing.

At the moment I plan to pick up a cheap Android tablet and get the Torque app going. I saw it in a friend's car and it had AFR and Vacuum readings up, thought that was a pretty badass combo.

#THIS
http://www.ft86club.com/forums/showpost.php?p=1238635

Boost/Vac, Coolant Temp, Intake Air Temp, Exhaust Gas Temp, Throttle Plate, Speed, RPM with Shift-light, Battery voltage, AFR, Oil Temp, etc.

Hell do both!

[nataku]

So I brought the car back to PTuning this morning to make sure I wasn't overboosting anymore since I still don't have the boost gauge yet. They said the exhaust leak was getting a lot worse and noticed the car was driving really strange. I basically have 3 main issues now:

1. Throttle tip-in is seriously unreliable. At 2k and 3k RPMs it feels like the car temporarily decelerates before starting to go which leads to a very jarring kick.

2. Throttle blips are delayed. The car basically just makes a louder farting noise instead of lifting the revs unless I blip a couple times.

3. Steady throttle provides unreliable acceleration. As the car works through the rev ranges it gives random small bursts of acceleration occasionally (and no I don't mean getting into boost it did this at 2500 RPMs).

Reading into these issues more it sounds like there could be injector failure happening, but we can't really diagnose it until the exhaust leak is gone. It is possible that the O2 sensor in the exhaust is forcing the car to run super rich because of fresh air getting in through the leak. I'll keep updates coming as I find out.

Might see a quick turnaround to Stage 1+ in my future if I have to pay for dyno and injectors!

[ecko04]

When you say injectors are you referring to port injectors or the direct injection seals?

That primary O2 isn't an O2 at all, it's an AFR. Only post catalytic converter is there an O2. The AFR is roughly $200...I found out the hard way.

Fix the exhaust leaks, which is what I thought was being done yesterday. It's hard to diagnose anything and you're just throwing money away to put it back on the dyno with major exhaust leaks. They throw off your tune, cause your turbo to run inefficiently, throw off your AFR readings, etc.

[Sportsguy83]

Originally Posted by nataku

Thanks for the recommendation. I mentioned that in my list of lessons because I do not have a boost gauge, hence the not following my own obvious advice.

Toan was saying I have a boost cutoff. I don't know if that is the same thing as overboost protection, but it sure sounds like the same thing.

At the moment I plan to pick up a cheap Android tablet and get the Torque app going. I saw it in a friend's car and it had AFR and Vacuum readings up, thought that was a pretty badass combo.

Word of caution with the P3 gauge, you won't be able to see AFR below 12 because the OEM AFR is not wideband. Not a huge deal, but still something to keep in mind.

Also I agree with @ecko04 fix the exhaust leak first and foremost and go from there.

[ecko04]

Originally Posted by Sportsguy83

Word of caution with the P3 gauge, you won't be able to see AFR below 12 because the OEM AFR is not wideband. Not a huge deal, but still something to keep in mind.

Also I agree with @ecko04 fix the exhaust leak first and foremost and go from there.

This is true! It's not that you can't see AFR below 12, but rather AFR below 11.7 is not as accurate, as verified on the dyno and by Toni. 11.7+ is spot on.

However, you can use an LC-1 or LC-2 (Innovate Motorsports) to connect to an analog input on the P3 Gauge, which is something I plan on doing in a few weeks.

I also run an additional sensor for oil pressure as well.

[Sportsguy83]

Originally Posted by ecko04

This is true! It's not that you can't see AFR below 12, but rather AFR below 11.7 is not as accurate, as verified on the dyno and by Toni. 11.7+ is spot on.

However, you can use an LC-1 or LC-2 (Innovate Motorsports) to connect to an analog input on the P3 Gauge, which is something I plan on doing in a few weeks.

I also run an additional sensor for oil pressure as well.

Good! I have AFR/Boost AEM Failsafe on the right and Innovate Oil Pressure/Temperature in one on the left of my cluster gauge.

[ecko04]

Originally Posted by Sportsguy83

Good! I have AFR/Boost AEM Failsafe on the right and Innovate Oil Pressure/Temperature in one on the left of my cluster gauge.

I've seen your snazzy cluster! The proper gauge pod!

[sw20kosh]

Where is the leak? A leak post O2 sensor won't do anything to the tune.