Turbo Optra - Now on tuned Haltech @ 225whp

[PrecisionBoost]

As far as the discussion related to intake manifold pressure vs exhaust manifold pressure I would like to make a few points.

1 )
The measurement technique used in this dyno video is flawed, a boost gauge is not an accurate measurement tool in this circumstance, the correct measurement tool is a water cooled piezo electric element inserted just before the turbine inlet. Manifold pressure has large fluctuations at high frequency, only a piezo electric element fed to a signal analyzer can give repeatable accurate measurements. The "boost gauge" only gives you a very rough indication of back pressure, it is not an accurate measurement, therefore you can not use it to compare pressure ratios of intake/exhaust. The biggest problem is that the boost gauge is connected to the manifold via a compressible gas ( air ) with a non-linear temperature change between the source and the gauge. If your rubber line was replaced with a steel reinforced line filled with a non-compressible fluid that has a small thermal expansion ratio it might be possible to get a reasonable average pressure measurement.

2 )
The measurement of ratio is only accurate under very specific circumstances, ideally in a laboratory environment. Manifold pressure is typically done in small steps while plotting both the compressor and turbine efficency charts.
That is to say they move the engine load/speed in small increments measuring the mass airflow, change in temperature and manifold pressures. They do not ramp the engine quickly, the measurements are done at a steady state where the engine is held at a particular load/speed for several seconds while the computer data logs the information to get an accurate average reading.

In conclusion, I'm not saying that this "boost gauge" measurement is useless, I am only saying that the number shown on the gauge is inaccurate and it is only a relative number. That is to say 20psi on the gauge does not indicate 20psi in the manifold, it's likely not even linear.

Example of what I'm saying:
inlet pressure 6psi - gauge pressure 6psi - actual pressure 8psi -- estimated ratio 1:1 -- actual ratio 1:1.33
inlet pressure 8psi - gauge pressure 7psi - actual pressure 11psi -- estimated ratio 1:0.88 -- actual ratio 1:1.38
inlet pressure 10psi - gauge pressure 8psi - actual pressure 14psi -- estimated ratio 1:0.80 -- actual ratio 1:1.40

Hopefully you get what I'm saying, it is a good tool to compare two turbos such as a T3 "45" and a T3 "60" or perhaps a turbo with different compressor or turbine housings so long as nothing but the turbo changes.

There will be a relative difference, but the difference will not be linear and it will not equal the real ratios.

When it comes to real automotive engineering, they use real time instruments and data logging systems, it's the only way to physically measure with precision and get repeatable results for calculating efficiency.

[Tony the Tiger]

As far as the discussion related to intake manifold pressure vs exhaust manifold pressure I would like to make a few points.

1 )
The measurement technique used in this dyno video is flawed, a boost gauge is not an accurate measurement tool in this circumstance, the correct measurement tool is a water cooled piezo electric element inserted just before the turbine inlet. Manifold pressure has large fluctuations at high frequency, only a piezo electric element fed to a signal analyzer can give repeatable accurate measurements. The "boost gauge" only gives you a very rough indication of back pressure, it is not an accurate measurement, therefore you can not use it to compare pressure ratios of intake/exhaust. The biggest problem is that the boost gauge is connected to the manifold via a compressible gas ( air ) with a non-linear temperature change between the source and the gauge. If your rubber line was replaced with a steel reinforced line filled with a non-compressible fluid that has a small thermal expansion ratio it might be possible to get a reasonable average pressure measurement.

2 )
The measurement of ratio is only accurate under very specific circumstances, ideally in a laboratory environment. Manifold pressure is typically done in small steps while plotting both the compressor and turbine efficency charts.
That is to say they move the engine load/speed in small increments measuring the mass airflow, change in temperature and manifold pressures. They do not ramp the engine quickly, the measurements are done at a steady state where the engine is held at a particular load/speed for several seconds while the computer data logs the information to get an accurate average reading.

In conclusion, I'm not saying that this "boost gauge" measurement is useless, I am only saying that the number shown on the gauge is inaccurate and it is only a relative number. That is to say 20psi on the gauge does not indicate 20psi in the manifold, it's likely not even linear.

Example of what I'm saying:
inlet pressure 6psi - gauge pressure 6psi - actual pressure 8psi -- estimated ratio 1:1 -- actual ratio 1:1.33
inlet pressure 8psi - gauge pressure 7psi - actual pressure 11psi -- estimated ratio 1:0.88 -- actual ratio 1:1.38
inlet pressure 10psi - gauge pressure 8psi - actual pressure 14psi -- estimated ratio 1:0.80 -- actual ratio 1:1.40

Hopefully you get what I'm saying, it is a good tool to compare two turbos such as a T3 "45" and a T3 "60" or perhaps a turbo with different compressor or turbine housings so long as nothing but the turbo changes.

There will be a relative difference, but the difference will not be linear and it will not equal the real ratios.

When it comes to real automotive engineering, they use real time instruments and data logging systems, it's the only way to physically measure with precision and get repeatable results for calculating efficiency.

Precise readings is always good, but I find it rather pointless to elaborate so much into getting "precise" readings on such a varying condition. You're trying to discredit existence's readings yet you don't even know what it takes to achieve a truly useable figure. I had access to such instrument, but there was no method to standardize the conditions to make precise readings useful. With the same engine, same turbo and same power output, I could manipulate exhaust pressure readings to almost double just by running the engine through unrealistic conditions for that certain engine. I can also manipulate this figure via fuel/ignition timing and cam timing changes.

Turbine inlet pressure changes rather easily. Torque falls and pressure falls with it. Late spark timing due to octane limitations increases the pressure big time due to incomplete combustion. We know the engine runs through an RPM band and boost curve, but where do we sample our readings to gauge efficiency then? How long do we "load up the engine" to get the standardized figure to be used for efficiency calculations? 10 seconds? 1 minute? Perhaps for a 1000+ WHP car, which cannot even physically spend more than 30 seconds at full boost and full throttle before it runs out of gear at 200+ mph?

A big power street car (e.g. my Camry) does not even spend more than 30 seconds under full boost before it runs out of gearing. Heat saturation on the manifold, or obtaining a steady state condition is not a priority. Due to the nature of such engine, the engine should never be locked at a certain RPM anyway unless I was trying to use my 900WHP Camry to haul a boat up a mountain.

There is no need to get so over technical on such a loosely obtained figure. Just by choosing a different location to probe the exhaust manifold can throw off pressure readings regardless of how precise your instrument is. A manifold with stamped collector vs a 15-deg merge collector will require a different location. The key is to find a spot that "makes sense" so that it's useful for tuning. This comes from experience only. On a log manifold with centralized runners, I usually take the reading closer to the exhaust valves to check for reversion and adjust cam timing accordingly. With a long runner front facing exhaust manifold on a drag car with open DP, I take the reading deep within the turbine housing where it necks down to half its diameter. The readings are used for plotting turbine efficiency maps which is important for a drag car.

[benzino]

You're getting your terms mixed up. PrecisionBoost is only talking about accuracy. you're talking about precision...

Accuracy is finding as close to the true value as possible; whereas precision deals with repeatability.
Accuracy would be determined by sensor placement and precision would be determined by standardizing and controlling as many variables as possible...

Ergo, you're both right, you're both equally pretty... and you both get to go to the ball

[PrecisionBoost]

Tony, the point I am making ( which you support with your response ) is the measurement is a relative figure as opposed to an accurate physical measurement.

Quite simply if all variables are generally the same ( position, air/fuel ) and you start playing with different turbo configurations ( housings and wheels ) then the measurement technique with the boost gauge would be a great tool to show if the intake/exhaust manifold pressure has increased or decreased with the change in turbo configuration.

This technique is perfect when you are inserting turbos ( such as the CT12B ) which do not have published compressor or turbine maps for mathematical calculation of expected results.

My concern however is with Exist3ence's statement that:

" So now think of the opposite of that - a ratio of less than 1:1. Take for example 1:0.7. I have seen this on very efficient setups - and no it does not mean the car is laggy at all, it will actually be very responsive"

My problem here is that the measurement technique used it is not an accurate physical measurement, that is to say his statement that there are efficient responsive cars running 1:0.7 is purely speculation because the measurement tool is not accurate.

The gauge is a great tool for building systems, it is however a horrible tool for giving a physical measuement as a statement of fact.

You could however say you measured 1:1.05 initially, decreased the turbine housing size and measured an improved 1:0.9 ratio.

That is say you can say you improved the intake/exhaust pressure ratio by roughly 15% but you can not say the real ratio is actually 1:0.9

If you had an accurate measurement tool you might find that the ratio may have been 1:1.9 initially and 1:1.6 afterwards ( which is that same 15% relative change in pressure ratio )


If you want a more accurate reading you need to remove the rubber hose and gauge and replace it with a steel tube ( 8-12" in length ) and use a piezo electric pressure sensor connected to a logging tool.

Garrett ( GSE_Turbo ) uses a piezo exhaust gas pressure sensor from a ford powerstroke diesel ( EBP sensor ) which sounds like a great alternative to the high priced sensors I was talking about.

The indirect piezo sensors ( such as the powerstroke EBP ) are only good to 400 degrees C, which is why there is a need for a long tube to decrease temperature.

The water cooled units I initially mentioned can take 800 degrees C, which allows them to go right into the manifold for direct measurement.


Hopefully this will clear up any confusion, I certainly see value in the relative measurement to say the ratio has gone up or down, but it can not be used to give a physical ratio such as "1:1.2" due to accuracy of the measurement gauge and the setup.

[exist3nce]

I know this thread has been dormant for a while.... but its almost that time of year again... Optra time! lol

I'm on the fence about what I want to do with the car this winter... I feel like I need to change something again haha

Possible plans / options ...

1) Bigger turbo again - but not as big as before - perhaps a used Subaru STi turbo.... my buddy has one that he'll let me have for free

2) Emanage ultimate to eliminate the additional injectors setup and just run larger primaries and also the Ultimate has much more compensation maps and functionality to give a better overall tune with stock ECU

3) standalone EMS ... considering the Haltech Sprint 500 due to decent price - still need to do a custom trigger wheel... would be nice to have complete control of everything right from scratch and run whatever size injectors I want as well as better ignition options such as COP

4) leave it alone and be happy with what I have ! LOL

[7-even]

still one for the bigger turbo and emanage ultimate. i think if you decide to push it again with turbo size and HP then you should move on to a standalone. actually i have a standalone with harness for the reno/forenza i might be willing to part with. let me know if your interested.

[exist3nce]

Even tho I think this forum is dead, here is my latest update:

Haltech Platinum Sprint 500 has been purchased

[7-even]

Ah yeah!!! Congratulations That's a serious piece of equipment right there. I'm impressed. Will you be able to pass inspection with the haltech? I know things are a bit different up there.

[exist3nce]

So alot has happened with my Optra project over the winter while I couldn't log in to this site... I've been updating threads on my other forums, but now I can update this one too!



Feb. 10, 2014

Spent the past 3 days wiring up the Haltech.... After a few glitches and mistakes we got the car running with the new setup!!


S2000 coil on plug FTW



That's a shot of it running - but we are not ready to tune just yet. Still have to clean / tidy up all that wiring and then sync up the timing and install larger injectors (stock injectors are still being used at the moment).

Some facts / discoveries:

- The Haltech Sprint500 was able to share the factory cam and crank sensors with the stock ECU. Both ECUs are able to read RPM, etc at the same time.
- The stock crank trigger wheel is a 60-2 pattern with magnetic reluctor sensor... I was previously told by someone else that is was a 36-2 pattern and was trying to use that with little success. Luckily the Sprint500 comes with a Motronic 60-2 pattern that I could use.
- The stock cam sensor is a hall effect and has just 1 window. Again luckily the Sprint500 has the 60-2 + 1 pattern
- The coolant and air temp sensors are able to be shared as well.... but it seems the Sprint500 does not have any suitable scale/calibration for them. I will either scale them myself, or just install dedicated Haltech sensors.

For convenience I made a quick swap harness for the injectors so that I can swap back and forth between which ECU is actually controlling the injectors in about 30 sec

More to come..

[exist3nce]

Feb. 18, 2014


- I chose S2000 COP because they are nice and compact with built in igniter which simplifies the wiring and also reduces the changes of EMI since there are no high tension leads (spark plug wires). Not to mention the S2000 ignition setup is proven to be very strong and reliable even at 600whp+

- As for the injectors, I still had the stock 200cc being used as primaries all this time with the 2x additional larger ones on the charge pipe. Half of the reason for going standalone was to eliminate the need for the 2x additional injectors and just be able to use 4x larger injectors as the primaries (more consistent fueling).


- We were able to sync up the timing and able to free-rev it up to 7000RPM without any issues. However.... When we put it on the dyno, under load at RPM's above ~4000 or so we start missing counts of trigger teeth - the higher we try to rev it the worse it gets and no amount of filters or adjusting settings seemed to help. When it gets bad enough the Sprint500 looses track of the engine RPM and basically shuts off the injectors. So it looks like I'm not as lucky as I thought with being able to share the stock sensors.... Will have to make the custom triggers now.

- Neither of the stock air or coolant temp sensors are usable with the Sprint500. I tried scaling them, but around ~50 deg C the stock ECU changes its pullup to adjust its resolution and there's nothing I can do to change this. Since I already had the AEM water temperature sensor+gauge with 0-5VDC output, I just used that signal and it works well. For air temp, I just installed a dedicated AEM air temp sensor in the charge pipe and wired it to the Sprint500. Both sensors required manual calibration/scaling.


Soo the car is actually driveable to about 4000RPM right now and its drives quite well considering the tune is still pretty raw - more to come when I get the cam/crank sensors figured out.

[exist3nce]

March 3, 2014

After some long hours this weekend we finally got it to fire up on the new custom crank and cam triggers. We managed to use the stock exhaust cam gear for both and build custom sensor brackets to get just the right angles and spacing which took quite a long while.

We were able to sync up the timing correctly last night with the new pickups, which confirms they are running properly and reading clean signals. Was able to free rev again to ~7000rpm without any hesitations or drift in the timing which is certainly a good preliminary test. Next will be back on the dyno hopefully in the next couple days to confirm all is good under load and tuning.

Here's some pictures of the custom pickups reading off the stock exhaust cam gear and also modification of the timing belt cover to accommodate the new sensors and allow for quick adjustments if necessary while maintaining a "stock" look. Left sensor is for cam and right is for crank.

[exist3nce]

March 11, 2014


So after a few more slight headaches playing with the sensor gaps and filtering settings I believe I've got it running right. Dyno tune happened a few nights ago and here's the final results:

225whp / 212 lb ft



Something interesting now that we have full control of timing is that we were actually able to squeeze about 10whp more out of this undersized turbo by lowering the boost a touch and running a little more timing. 11.5psi on stock ECU and now about 10.5psi with the Haltech. Overall I'm pleased with the numbers - they are where they should be for this turbo that is beyond maxed out LOL.


Dyno Video

OptraDMTCT12bS500 - YouTube

[exist3nce]

April 10, 2014


Finally had a chance to fabricate a bracket/holder for the new coils

Now they are nice and secure and pretty looking.. lol

[Daniel]

Wow! What a nice job.
Sometime I watch STREET OUTLAWS on Discovery and I'm always impressed what those guys can do. I particularly like Farmer Truck. Do you plan to race too?

Congrats for your coming soon wedding.

[exist3nce]

Wow! What a nice job.
Sometime I watch STREET OUTLAWS on Discovery and I'm always impressed what those guys can do. I particularly like Farmer Truck. Do you plan to race too?

Congrats for your coming soon wedding.

Thanks man! Although I think you have me confused with someone else? I don't have any wedding coming soon lol..