kungpaosamuraiii

As greenfire said before, the TRD has:

It may have a different name but it serves, I think, the same purpose as a BOV. I've never heard of a bleeder valve but I think this bypass valve sounds a lot like it "bleeds" off pressure.

This may very well be Toyota's solution to the fuel problem. With this internally valved operation it wouldn't even necessitate looking into anti-stall features. The reflash is still probably primarily for emissions.. but then again:

This "sophisticated calibration" sounds to me like the work of the reflash.

The beef I have with this, however, is that, if the reflash results in higher power output due to sophisticated calibration, then it should be able to produce much more power than the 200hp, 173tq that it's advertised as making. It should make more power because ZPI's stage 0 kit does not have any other "sophisticated calibration" than the OEM ECU yet boasts about 230 hp at same psi. If the reflash optimizes fuel for boost than we should be able to expect at least the same amount of power as the ZPI stage 0. That is, if it's for power. This reasoning leads me to believe the reflash is nothing more than an emissions flash. Perhaps someone should try getting the S/C and swapping out the reflashed ECU with a stock ECU and see if power is gained.

ScionDad

I've talked with a local dealer to find out 2 things.

1) Is the ECU flash reversable?
2) If it is, can they flash my turbo ECU and see how it performs....

If not well, then flash it back. They are interested, but would need to see the kit first to find ou t if it's reversable. They haven't seen a turbo TC yet, so they are interested in my request.

TurboCustomz

It is entirely possible that TRD, in all their years of making performance parts for cars, has decided, for one reason or another, that trying to make that much power on the stock engine configuration is not the best idea for the longevity of the engine. You have to remember, even with the TRD supercharger upgrade, the car still has to last 7 years or 70.000 miles. What do we know about these cars? They have forged rods in them, they have a high temp coating on the piston tops, and they have CAST rings.

The stock ECU in these cars is very smart, as we have already stated. However, you can not expect the stock ecu to just automatically adjust for boost on it's own, but run completely fine and get the fuel economy that it gets when there is no S/C present. The ecu is calibrated to run under non-boosted conditions from the factory. There is no MAP sensor and the car does not SEE boost on the stock setup. It only monitors air flow with the MAF. It MUST have some sort of calibration made to it to live up to the standards that you would expect from a STOCK car. Not to say the car wont run with boost on the stock ecu, because we all know it will. However, it will not run like a car should off the showroom floor.

On that note, I will say this. These cars run excessive timing on the stock ECU. This I believe is the reason why so much power can be achieved with stock settings in place and only fuel calibration. I know for a fact, that my car was running OVER 1000 degree's at cruise speeds of about 65-70mph, out of boost, in the bottom of the down pipe. I would guess its closer to 1200 degree's in the manifold. Now, all cars are different, but thats HOT for any car. In an EVO 8 for example, if you see over 1100 degree's on an EGT gauge, with the stock engine, you let out. Im sure that the reflash from TRD compensates for the aggressive timing to allow the car to run more safely and still maintain the life of the engine.

TRD's moves in this matter can be considered conservative, but I think we should all pay close attention to what they do, and consider why they do it. This isn't THEIR first time working with their own product. Just some food for thought. For everyone.

Charles

lo_bux_racer

Degrees C or F? Supras back out at 900C above the turbo, 700C below the turbo. The turbo typically uses about 200C. I don't know what the temperature range of the OEM planar a/f sensor is, but Bosch wideband sensors don't like to be over 900C for any length of time which is typically why they like to be about a meter from the exhaust port.

FWIW, I completely agree with the supercharger tuning. Reliability has to be first, or they'll lose their asses with warranty fixes. While some complain about the price of the supercharger, for what you get it's pretty cheap. I doubt anyone on this board knows the details of getting CARB approval, but I've been following Powerhouse Racing's CARB legal single turbo upgrade for '93 - '98 Supras for more than 2 years now, and they keep getting kicked back to square one by CARB. CARB approval is a HUGE effort, and they have to amortize that cost over all the superchargers they expect to sell along with paying for the rest of the design, not to mention the bits and pieces, and then they have to provide enough room for error to include a warranty. That's one hell of a feat.

Something else that seems to be missing from the discussion - 200hp and 173 ftlbs of torque. If you understand anything about hp calculations, that should scream something to you. Without changing the cams or exhaust, TRD has moved peak power ABOVE 5252 rpm. Notice the stock engine has similar hp and torque numbers. That's because they make peak torque and peak hp pretty close together in a relative sense. With 200hp and 173 ftlbs of torque, they've moved the entire powerband to the right and made the engine deliver more power all the way to redline. If you look at the charts on the TRD pdf, you'll see a HUGE increase in the area under the curve, and the power stays strong all the way to redline. It's a completely different power delivery from stock, and it gives up none of the friendliness of the stock engine.

So let's stop knocking it for this and that, and see what the real world results are before passing judgment.

SlowtC

As lo_bux_racer somewhat alluded to, these temperature limits seem pretty conservative, assuming you're measuring in Fahrenheit (if in Celsius, they seem dangerous). At WOT nearing redline, my Talon regularly hits 1500 deg EGTs at the manifold on stock internals (pump gas, 20psi, lots of mods, 8.5:1 compression). Timing peaks at about 23 degrees, with little to zero knock. Although I haven't driven a modified EVO 8, I highly doubt 1100 deg is the limit considering it is the same basic motor with better parts from the factory than a DSM. Just thought I'd throw that out there.

That said, this is a very interesting thread. I am looking forward to adding some form of forced induction to the tC in the future, hopefully in the form of a turbocharger, and am hoping that the tuning issues get worked out. I've learned that good tuning is well worth the money when it comes to going fast consistently. It is also the safer way to make more power. I just hope that it doesn't come down to a standalone being the only option for the long run with our tCs.

kungpaosamuraiii

Charles, that IS food for thought for me. I hadn't even considered reliability and warranty claims. The entire point of a supercharger in lieu of a turbocharger is to create the sensation of larger displacement. Despite the turbo-esque lag, the s/c's power curve mimics that of a larger engine's power curve. So it makes complete sense that TRD will try to keep power to a reasonable level rather than go all out and achieve a ride that is nowhere close to a stock car with a larger engine. Afterall, TRD promised a supercharged ride equal but quicker than the stock setup's ride.


By shifting the entire RPM band to the right, the difference in the integrals is about 250 by my very rough calculation (estimating what the number was and adding my observed difference between the two lines' integrals.) What does this value mean?

Well in anycase, I still believe the power output is a little low for forced induction, in my opinion (in comparison to how much more power is generated from other supercharged cars like the Cobalt SS that makes 5 more bhp with a .2 disadvantage in displacement).

However, I still think that the numbers to be had from the s/c in terms of actual performance - timed runs on either drag strips or road tracks or auto x runs - will surprise us in a good way.

TurboCustomz

To start, my car hasn't rolled over 6K miles yet. Put that in the back of your mind...

You're absolutely correct. Your talon, with its 8.5:1 compression, and turbo designed engine and ecu most likely hit those temps at WOT near redline and not have many issues. However, our stock n/a built tC's, with 9.5:1 compression, and N/A designed ECU's are hitting 1100 degree's Farenheit, at CRUISE speeds with no boost on the highway. Like I said before, my egt sensor is actually in the very top of my S Pipe. So the manifold I can only speculate, but be fairly confident, is seeing in excess of 1300 degrees at the same cruise speed conditions. My point here is that where you car, which is designed to save itself when it see's ANY detonation, and is built to handle those conditions, can see those cylinder temps under load for brief periods of time and be perfectly fine. The tC's are seeing the temps constantly, on any road trip, on any highway blast across town, time and time again, day after day. Under load, the egts get much hotter, as Im sure you already know.

Simply put, the engines can NOT handle 10psi or more with the stock ecu handling timing for what would be expected mileage out of these cars. I know these engines, fairly well, I'd venture to say better then almost anyone on here. Im not talking paper specs and theory of what they SHOULD handle. Im talking first hand experience, had the engine apart, seen what they will do with boost, seen what they will do with nitrous. I know what it takes to make these cars fast, and I know what it takes to blow the rings out of them. Trust me. I've done both.

lo_bux_racer

Thanks for the input. Most of us are coming from another platform with different experiences and results. It's great to have someone with direct experience willing to share some knowledge.

If I had all day to devote to this...unfortunately, I'm also busy making a living doing something else entirely different, and making enough money that it wouldn't make sense to open a tuning business.

SlowtC

TurboCustomz: I was mainly referring to your comments about the EVO VIII when I made the post about DSM motors. All temps I mention are at the exhaust manifold. Average cruising EGTs are around 1400 deg F, while WOT runs will often peak at 1550; this is for all 4G63 motors including the EVO. I'm not sure why you said that you would back out of it when temps hit 1100 in an EVO VIII.

Also, I don't think I'm fully understanding your statements about the tC ECU's ignition timing. You said that at cruise, you are seeing 1300 deg F EGTs, which is relatively normal, if not a little low. That means at cruise, the ignition timing is advanced quite a bit.

I'm not sure how that correlates to WOT situations though. At WOT, if the ECU sees too much airflow through the MAF, it would increase fuel and decrease timing to account for it (which would increase EGTs). Additionally, if the ECU detects any knock, it will cut timing. Why is timing control necessary then? With nitrous I can see it being an issue, but with turbos, the additional air should cause the ECU to be very conservative with timing.

Anyway, I'm not trying to argue; just trying to understand and learn. I hope that's how the post comes across.

TurboCustomz

It didnt come across as arguementative at all. Let me start by reitterating that all temps that I have observed are at the bottem on the down pipe with is at least 18 inches from the manifold. Therefore you can assume with some confidence that the manifold temps are 200-300 degree's hotter then a post turbo reading that far away. I wish I had manifold temps to go by but I don't. I think that confused a few people in the begining.

As far as my timing comments. Peak timing at WOT is different for every car because each car has its own configuration that can handle certian limitations. Have you ever tested a Toyota knock sensor from a tC? It works off the a/f readings and not off of sound. You can bang on your tC block while watching knock voltage and you will get nothing. Hell, you can bang on the sensor itself. It doesn't work the way conventional knock sensors did and can cause problems in this case. When you tune the car, to what the stock ECU thinks is RICH, then the knock sensor see's no reason at any time to pull timing because it thinks the car is overly rich anyway. If anything, it will increase it to max to compensate. This is why the Scion Speed guys always said that they tuned their car to mid 12:1 afr's because thats where it made peak power. Im sure it did since the stock ecu is designed to acheive a very safe (for an NA car) 13.3:1 A/F under WOT. However, with our cars with turbo kits on them, we tune the car much richer and the knock sensor is seemingly useless at this point.

Using the emanage ultimate, which hasn't yet been the greatest system I must say, I have seen the car run as much as 23 degree's peak timing under load on pump gas. At this point I can hear audible knock and the car is pulling no timing at all. That was with sub 11:1 afr's. On a hot day, with some 91 in your tank this is bad bad news.

As far as the additional air is concerned, the MAF on a tC is 0-5 volts. The emanage uses a boost cut setting that clamps the voltage just before the car thinks it has a out of range sensor and you compensate the fuel in the tables on the unit. For timing however, the ecu doesn't see any more air and therefore has no reason to pull timing. Not to mention when you increase the size of the MAF piping you are flowing a larger volume of air and the MAF doesn't see it.

My biggest point was escaped here I think. These cars have incredible technology behind them and they are built amazingly strong for what they are. However, they have a weak point and it has been found. Im sure it will become more appearent in the up comming months and steps will be taken to preserve the life of these engines. There is a reason the TRD units only make so much power, there is a reason the turbokits.com units only make so much power. I can take a junkyard chevy 350 engine and spray a 200 shot on it for a whole season, but thats all im going to get out of it.

lo_bux_racer

Have you seen the technical description of the knock sensor on page EG-39 in the New Car Features manual? They claim it has a range of 6kHz to 15kHz, and it is completely different from a "conventional" resonance type knock sensor (that we all know from previous engines). The claim is more precise ignition timing can be achieved because the sensor is able to detect knock even when the engine knocking frequency is changed. They also show a graph of the output voltage, and it isn't anything remotely like the kind we know, mostly because the output voltage never spikes. It either exists, or it doesn't.

How they've incorporated that into the timing algorithm is anyone's guess, but from what you've said it sounds like they've done something that isn't intuitive.

23 degrees doesn't sound like a lot of advance for an 88.5mm bore, but it seems the current crop of 87 octane fuels are not very happy with 9.5:1 and 23 degrees full advance at WOT. I've run 28 degrees in a 78mm bore on an aircooled engine at 11.25:1 without issues, but that was also on 93 octane.

AFA the MAF, isn't it possible to increase the diameter of the tube and extend the range of the device? Not the voltage, but the maximum flow represented by the 5v signal. I realize this makes individual increments of flow different, but if you aren't too radical with the size increase it might be possible to extend the flow measurement capability before you hit the fixed value. Has anyone tried that yet?

rhythmnsmoke

^^^^yeah, what he said...

Joe_Dezod

I'm running a 3" MAF pipe. It's been working well on our kit so far. We found out the 244whp, 255tq number was with the clutch slipping in 3rd. So I'll see how it works out when the new clutch is in.

Also... At WOT, the car goes into a defaul pre-programmed MAP. It doesn't make fuel corrections at WOT. So you can very easily get a perfect WOT A/F tune. The partial throttle tune is what is tricky. We're still trying to find out what the best option is for tuning, using either TPS, MAF, or Greddy MAP. Testing MAP in 2 weeks (I'll be in FL next week).

paul_dezod

GReddy MAP will probably yeild the best results.

Joe_Dezod

I agree. We already discussed why over the phone today. We'll prove the theory true soon.

depogrig

splitsec.com has a device to put the car in open loop whenever there is boost pressure. have you considered something like this to help with part throttle tuning? or did eveything get worked out with the second dyno session?

mattssi

A few is300 people tried that, I think they ran into some very poor mpg issues amonst other things. But it did help w/ the a/f's and tuning

lo_bux_racer

http://www.monsterhorsepower.com/one...3-Images/0.jpg

You guys must not be familiar with this car or its owner. It ran in the 2003 One Lap of America, with a strong finish and it completed all stages after being driven from Calgary and driven home again. Reg has forgotten more about Toyotas than I'll probably ever know.

It has all the same features the tC has including drive by wire throttle and VVTi. It works flawlessly.

mattssi

Are you refering to the splitsec unit?

F it - standalone!!

SlowtC

Sorry if you mentioned it before because I couldn't find it, but what does he use for fuel management on that IS300?