Tacoma ECU Tuning for 4.0L

Eat a good lunch...then get it on!

 

My TRD tune runs so rich it momentarily drops to 9.4 just before a shift, and when down in Phx at 1500' at that point I get a backfire. I'm guessing it's over fueling and I'm getting a combustion pop from too much fuel right then.

And that was with the 2.85 pulley. I saw about 8.5 boost tops there last weekend and the backfire actually seemed to be a little less with the 2.7 pulley, but still there and still hitting 9.4 right before the shift. Or...it's got a trans flare that allows it to rev up and the tune compensates with more fuel for protection. Havnt quite figured that out just yet.

 

"Tuners"

Need some additiona OV "tuning education".

I knowing everything one reads on the net is not necessarily gospel, so one must ask questions. In my search efforts to further enlighten myself on tuning Tacoma ECUs I've read, several times, almost all manufactures tune for emissions first, MPG second, and performance third. But, the tuners goal, in general, should be to reverse that alignment to get the most out the vehicle.

This thread alone has shown me it's just not that cut and dry and many more computer controlled factors must be take into consideration when tuning. So, I'm assuming that's one of the big differences between the OV Hand Held unit and the DIY unit. Am I right?

Question: can each the 5 pre-sets included with the OV Hand Held unit be defined by ranking what factor, Emission, MPG or Performance is first second and third or is that too general of categories for this application?
Thanks
Bob

 

Handheld is easy, Self tune is medium to hard depending on level of expertise. All the posts of people getting the calibration message are just in the process of setting up their handheld, it's really quite simple for both applications for setup. Self tuning requires your own computer, no handheld device, and a separate dongle plugged into your obdII port. You're paying more for the option to tune yourself, and mainly paying for the licence, hardware is pretty cheap.

 

I am seeing right as we approach closer to rev limit it dumps super rich

 

Wish I had that problem.

 

Too bad it's not in 4th. The numbers would be a little higher because you would be a closer ratio of 1 to 1. Either way still good numbers. Can't wait to see the outcome. Need to put it in the forced induction Dyno thread afterwards.

 

Will do!

 

Good ole inconsistent TRD flash.

 

alright quick break while the truck cools off.

a bit of info and what was worked on, things noticed
- stock TRD flash, when first entering boost will dip very very rich and then progressively lean out, then dump fuel near rev limit.
- heatsoaks pretty quick (80* room temp). 5-6 runs and the heat exchanger / SC is hot
- camshaft tuning needed quite a bit of work
- fueling is very inconsistent. (fixed )


some things I would recommend for people with smaller pulleys
- definitely look into a larger heat exchanger core
- octane, octane, octane. It is doing decent with this 91 and 2.85, but a 2.55 on 91 and stock TRD ignition sounds scary
- I have no doubt that anyone out there running the OE TRD tune with more boost then this truck is running (2.85) with ignition stripped, stock TRD ignition timing is NOT safe for something like a 2.55
(luckily the ecu uses multipliers so it can strip out a ton of ignition, and save that multiplier value, so it will just be always down on ignition)
- Just like the 3.5, the exhaust looks restrictive. The exhaust on this car in particular looks like a choking point with 4 cats and extremely small primaries.

I'm not going off knock readings or what the ECU is telling me I have det ears and aftermarket knock sensors hooked up to the block listening, I was hearing knock on stock TRD tune around 4500 RPM


more info tonight.

 

Smaller pulleys?

 

Excuses to upgrade exchanger and maybe the pump? Cool!

 

Any idea where to get a bigger exchanger?

 

Frozenboost.com or pretty much any aluminum radiator you can fit.

 

right lol


alrighty guys we are all done for the day, info tonight

yep frozenboost has good cores. two of the fastest twin turbo Q50s I've tuned use cores from them.

 

It's already night time on the east coast though!

 

Thank you for the insight and recommendations! A lot of learning going on in Tacomaworldland tonight!

 

Tacoma TRD Supercharged 4.0L 91 octane results-

Dyno charts below showing gains made only through tuning. Majority of work done today was cleaning up fueling and finding the most beneficial valve timing targets.
net gains:
Stock Tune
323hp stock / 343hp 91 tune
318 ft lb / 329 ft lb (with peak ft lbs difference over stock 20+)
(note dyno says "flywheel" numbers only because of shootout correction. This is near equivalent to dynojet numbers, not actual flywheel)
testing conditions : +/- 80* F




information about the tune- what was changed

The gains made today were solely by cleaning up fueling, finding the most beneficial valve timing angles, and eliminating detonation.

It took about 3 hours and 15+ flashes to dial in and clean up the stock fuel targets, which are very inconsistent. Extreme dips where AFR would go excessively rich, and the next run leaning out.
Our fuel calibration now has AFR around 11.3-1.4 through mid range and target of 11.6-11.6 at peak boost.
We were able to completely eliminate the stock dip where the fuel would go extremely rich when you first get on it. now it fuel will smoothly taper as necessary.

Fuel AFR measured by external wideband for accuracy.

Note- Fuel target tuning on these ECUs is tricky, and small changes can make wildly different results.
Folks with our DIY Tuner will get todays Fuel development that we did, to save you a lot of time chasing AFR.

A quick explanation as to why tuning fuel is tricky,

The stock TRD supercharged tune fuel map has values at peak boost / higher RPM at 255. Because of the map being 8byte data, our limit is 0-255. So you cannot add more fueling by traditional ways of editing the enrichment map


There are two maps in the ECU that compensate the base fuel enrichment map so that you can rich or lean out fuel as necessary.
On the stock TRD tune and 2.85 pulley peak boost AFR was 12.3+, lean enough to cause detonation. Only near redline did we see a huge enrichment where AFR would drop to below 10.

Once fueling was right we spent a while to modify and tune valve timing.
changes made -
-advance in lower to mid range and across the board, which gave us more torque everywhere.
-adjust valve timing in out of boost / moderate load range which significantly helped with engine response.

Ignition timing changes were made to clean up spots of detonation. Only minimal ignition was able to be added. Nearly all gains today were made solely by fixing fueling and camshaft tuning.
That being said, the TRD supercharger runs hot, and getting the best ignition is going to take a combination of good high octane fuel, and some modifications to keep the cooling system from heating so quickly.

I noticed it only takes about 3-4 runs before the supercharger is hot enough that the ECU will start to pull out timing. This is also when fueling will start to be all over the place, because of maps that control fuel compensation to air temperature. (fixed)

This truck also had all 4 cats, stock Y pipe. The header primaries were insanely small (maybe 1.25 inch?).


Overall thoughts :
Today we made some very good progress and got to see the supercharger in action. Tuning went very well and the truck is very responsive to changes.
The purpose of today's tune was to clean the inconsistencies and find the most beneficial valve timing. the truck was not pushed hard.

After hearing the engine with my Det ears today I would personally recommend against running smaller pulleys on a stock TRD tune unless you have additional cooling mods to keep the superchargers cooling system from getting hot, and or higher octane / methanol. You might be okay with 93 and a 2.85 on stock ignition, but there is simply no way 2.55+ stock ignition and 91 octane is safe.

 

Any ETA on when self-tune kits will be available again?

 

Good stuff Mat! The truck ran great on the way home, feels a lot smoother through the powerband.