Twin Turbo 928 fixed and back out there terrorizing the streets!
#166
Thread Starter
Nordschleife Master
Besides the problem with excesive heat I believe there is a problem with pressure affecting the accuracy of the sensor as well, maybe the problem is more related to gas density rather than pressure, still I seem to recall somebody telling me there is an issue. I reckon it was on original minis with the 5 port head he wanted to measure the mixtures of the 3 individual runners before the turbine to see if mixtures were the same across all four cylinders, but oxygen sensors wouldn't work in the pressurised atmoshere. Anyway just something to be aware or wary of.
So, yes, on the one hand, if the pressure is outside the operating range of the system this will not work. On the other hand, if the pressure is within the operating range of the system, one can potentiall eliminate two other sensors and tap into those pressure and temperatuer signals directly!
#167
Racer
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From: Adelaide South Australia'79 5spd twin turbo
OK Good luck
I must add I'm quite enjoying how your endeavor is coming along, John mentioned it to me quite some time ago, I firmly believe you will reach your goal, and probably easier than you expect, I also expect that the currently fitted engine will make some decent numbers before it gives up.
Keep it up
Cheers Roy
I must add I'm quite enjoying how your endeavor is coming along, John mentioned it to me quite some time ago, I firmly believe you will reach your goal, and probably easier than you expect, I also expect that the currently fitted engine will make some decent numbers before it gives up.
Keep it up
Cheers Roy
#168
Craic Head
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You can buy that cold air intake and air filter system, install it on a NA car, take out the stock air filter element inside the box, and see if it makes any more power than stock. I would guess that most of the impact would be visual and the engine power would not be impacted much if the engine is otherwise stock. I do like the look though.
And Tuomo: I'm really sorry I didn't check this thread out sooner. For some reason I thought it was about a concert or something.
Very cool stuff, unbelievable. I heard you referring to the TT project in other threads but didn't know you had all this info posted.
#169
Thread Starter
Nordschleife Master
Bosch LSU 4.2 tech spec
By the way, in case anyone needs this, here's the link to a fairly detailed technical info on the Bosch LSU 4.2 wideband lambda sensor:
http://wbo2.com/lsu/Y258K01005e03mar21eng.pdf
It'd be interesting to see what information a competent person (not me) could extract from those wires...
http://wbo2.com/lsu/Y258K01005e03mar21eng.pdf
It'd be interesting to see what information a competent person (not me) could extract from those wires...
#170
Drifting
Those sensors are good enough to see individual cylinder misfires. AEM widebands use Bosch sensors. However, the AEM controller does not spit out data nearly fast enough to indicate the misfires. Nor will a Innovate controller give you that level of data. You need lab grade controllers like ETAS or whoever else to be able to decipher the data. And then you need some data acquisition that samples the controller fast enough to see what it's telling you.
#171
Thread Starter
Nordschleife Master
Those sensors are good enough to see individual cylinder misfires. AEM widebands use Bosch sensors. However, the AEM controller does not spit out data nearly fast enough to indicate the misfires. Nor will a Innovate controller give you that level of data. You need lab grade controllers like ETAS or whoever else to be able to decipher the data. And then you need some data acquisition that samples the controller fast enough to see what it's telling you.
Big fat reader warning that I don't know what I am talking about here.
#172
Three Wheelin'
The fora aren't currently accessible at the Innovate site, but I had asked them a few months ago about the practicality of using an oscilloscope to read the controller output so that I could adjust injector trim (on my MicroSquirt motorcycle project) and individual carburetor idle mixture (on my "other" motorcycle). They quickly replied saying that this was perfectly feasible and that they had done it in the past.
With a two channel scope, you could synch trigger based on the hall sender signal or inductive pickup of #1 ignition and count exhaust pulses in the WB signal from there.
BTW, I played around with this on the MicroSquirt project, but then decided to build a new manifold for it, and then got sidetracked onto a bunch of higher priority tasks. The manifold's done, though, and I should be getting back into this in the next few weeks.
With a two channel scope, you could synch trigger based on the hall sender signal or inductive pickup of #1 ignition and count exhaust pulses in the WB signal from there.
BTW, I played around with this on the MicroSquirt project, but then decided to build a new manifold for it, and then got sidetracked onto a bunch of higher priority tasks. The manifold's done, though, and I should be getting back into this in the next few weeks.
#173
Thread Starter
Nordschleife Master
The fora aren't currently accessible at the Innovate site, but I had asked them a few months ago about the practicality of using an oscilloscope to read the controller output so that I could adjust injector trim (on my MicroSquirt motorcycle project) and individual carburetor idle mixture (on my "other" motorcycle). They quickly replied saying that this was perfectly feasible and that they had done it in the past. With a two channel scope, you could synch trigger based on the hall sender signal or inductive pickup of #1 ignition and count exhaust pulses in the WB signal from there. BTW, I played around with this on the MicroSquirt project, but then decided to build a new manifold for it, and then got sidetracked onto a bunch of higher priority tasks. The manifold's done, though, and I should be getting back into this in the next few weeks.
#176
Thread Starter
Nordschleife Master
900 mile shakedown + dyno
I just got home from shaking down the car. Drove 914 miles today with it. No radio -- just the exhaust, fuel pump, and radar detector providing the information and entertainment.
The car sounds like group of one percenters riding in formation.
The tune is good in steady state, a little more work to be done with the transient response.
We also did some dyno pulls. The hp numbers are of no significance, it was just some pulls in a 100F warehouse. The purpose of the pulls was to get the data needed to construct the rpm specific boost profiles.
Dyno event was fun though. We got a last minute time slot, and had to wait for these guys to tune a carb. It's a big block hemi car with about $80k work done. (Doesn't make as much power as a twin turbo 928, by the way.)
While waiting, I checked out this car. That's a "real" Shelby, built this year.
Finally, our turn. The car's strapped on in the photo. This shop doesn't do turbo cars regularly, so the instrumentation wasn't best suited for our purposes. We got all the data, but had to be reading three separate systems the same time.
They do all sorts of race cars, and had set up the dyno to trigger an error code with 180 mph tire speed. With the 2.2 rear end, we made the dyno tilt on the first pull. Little hacking and limit was upped to 200 mph, and that we could work with.
In the spirit of full disclosure, here's what the first session yielded in terms of results. Just a first stab, now it's time to use those curves and the data logs to come up with the boost maps.
The car sounds like group of one percenters riding in formation.
The tune is good in steady state, a little more work to be done with the transient response.
We also did some dyno pulls. The hp numbers are of no significance, it was just some pulls in a 100F warehouse. The purpose of the pulls was to get the data needed to construct the rpm specific boost profiles.
Dyno event was fun though. We got a last minute time slot, and had to wait for these guys to tune a carb. It's a big block hemi car with about $80k work done. (Doesn't make as much power as a twin turbo 928, by the way.)
While waiting, I checked out this car. That's a "real" Shelby, built this year.
Finally, our turn. The car's strapped on in the photo. This shop doesn't do turbo cars regularly, so the instrumentation wasn't best suited for our purposes. We got all the data, but had to be reading three separate systems the same time.
They do all sorts of race cars, and had set up the dyno to trigger an error code with 180 mph tire speed. With the 2.2 rear end, we made the dyno tilt on the first pull. Little hacking and limit was upped to 200 mph, and that we could work with.
In the spirit of full disclosure, here's what the first session yielded in terms of results. Just a first stab, now it's time to use those curves and the data logs to come up with the boost maps.
#178
Thread Starter
Nordschleife Master
Because the shop was old-school American V8 place, their system didn't have a boost pickup/hookup. Since the car is S4, it doesn't have a MAP sensor. (Yes, I'll put one in when I get around to it.) The boost gauge / controller has the pressure transducer built in and doesn't have signal outlet. So what we had to do is set the boost controller to target certain boost and then have one dedicated human being watching the gauge to tell us did the controller actually deliver the set point. With these disclosures, on the graph the highest pull had 13.5-14 psi boost, the middle on about 12 psi, and the lowest about 9 psi.
The conditions were less than ideal. The dyno place was a bit like a Finnish smoke sauna!
I am not putting much stock in these dynojet results in general, and I am not making an exception here. The drag strip trap speed will tell us the truth once we get there.
Overall, John's system is pretty incredible. I drove four hours on the fifth gear with the 2.2 rear end. The car accelerates on the fifth gear at 65 mph well enough that once you are on the highway in light traffic on the fifth gear, changes are completely unnecessary. I forgot I was driving a manual car on two occasions! (Nothing too embarrassing.) Downshifting to fourth and flooring the pedal would then turn Bruce Banner into the Incredible Hulk. And this with an engine that is completely bone stock apart from John's turbo system.
The conditions were less than ideal. The dyno place was a bit like a Finnish smoke sauna!
I am not putting much stock in these dynojet results in general, and I am not making an exception here. The drag strip trap speed will tell us the truth once we get there.
Overall, John's system is pretty incredible. I drove four hours on the fifth gear with the 2.2 rear end. The car accelerates on the fifth gear at 65 mph well enough that once you are on the highway in light traffic on the fifth gear, changes are completely unnecessary. I forgot I was driving a manual car on two occasions! (Nothing too embarrassing.) Downshifting to fourth and flooring the pedal would then turn Bruce Banner into the Incredible Hulk. And this with an engine that is completely bone stock apart from John's turbo system.
Last edited by ptuomov; 07-19-2010 at 10:53 AM.
#179
Supercharged
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From: Back in Michigan - Full time!
Congrats on the car. While you you are being humble and discounting the numbers they are, quite nice. One thing I remember from when I was dyno tuning my car, the shaky/wavy portion of the dyno graph usually indicate knock, or something else wrong with the tune.
Did you guys have the SharkTuner logging for knock and overall advance? I'm also surprised the shop didn't have a hook up to record boost - every other dyno shop I've seen has this. Seems odd.
How was your AFR? Transition is almost impossible to tune on our cars. I've finally got mine to go to the 12's as soon as it sees 1psi. It's a beautiful thing.
Did you guys have the SharkTuner logging for knock and overall advance? I'm also surprised the shop didn't have a hook up to record boost - every other dyno shop I've seen has this. Seems odd.
How was your AFR? Transition is almost impossible to tune on our cars. I've finally got mine to go to the 12's as soon as it sees 1psi. It's a beautiful thing.