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Hardware mods & T7 adaptation

9.3K views 29 replies 10 participants last post by  California Saab Tuner  
#1 ·
Hi all,

Can somebody give me some more insight in the effect of hardware modifications (like intercooler, inlet pipe, sports cat etc..) on a stock programmed T7 ECU? Does the ECU adapt to them in a correct way?

Best regards,
Hans-Martin
 
#2 ·
A number of people have noted that the T7 engine management does change a/f ratio slightly based on modifications to the engine.

IIRC some people found that installing an upgraded intercooler or exhuast made things run lean.

It should be noted however, that the engine can tolerate a leaner condition with better exhaust scavenging and intercooling. So far I don't know of any harmful effects from just installing a turbo back exhaust and intercooler.

Anything which alters the backpressure will change the Volumetric Efficiency of the engine. Getting more exhaust out of the cyllinders gets more air/fuel into them. Because there is less exhaust, there is less residual heat, so the cyllinders are not any more likely to detonate. However the engine has no way of knowing about the additional air going into the engine since it is programmed with the VE that the car had stock. When cruising the Air Mass Meter determines fueling. But when under load, it's open loop with the pre-programmed map, and I don't think it adapts enough.

At any rate, the T7 engine runs much like the T5 did at full throttle. So if the modification doesn't hurt a T5 engine, it probably won't hurt the T7 engine.

In fact you can run the T7 engine without the Air Mass Meter all together. Then you basically have a T5 engine with different internal bits and pieces, and a number of different ECU codes.

To be safe, buy a wide band a/f ratio meter before making any modifications. This will allow you to make sure you aren't doing anything harmfull. You can source an a/f ratio gauge here:

http://www.zeitronix.com/Products/zt2/zt2.htm

Keep on Saabin'!
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Dubbya~
 
#3 ·
Changing to a 3" exhaust + race cat can cause a CEL to light up with stock software. This info is confirmed by Fredrik of MapTun. Same goes for a big intercooler on stock software.

I had loads of hardware mods with stock software, and no CEL. Car seamed to run fine, but the dyno curve was very bumpy, there was not really much more power gaoin over the unmodified car and Tech reading showed down-adaptation by the ECU.

If you change the hardware, it is better to change the SW, too.

Yours,

Philip
 
#4 ·
I am going I think for the Maptun Stage 3 and was thinking of getting the Abbott big intake pipe and turbo delivery pipe to get it up to 302bhp (on paper !)

speaking to a supplier for Maptun, he said that by adding the abbott mods it is unlikely that I will get the extra 22bhp as the ECU will compensate and hence still give me 280bhp.

I guess if I went abbott, they would map the ecu to account for the various add ons ??

I think this backs up what you are saying.


regards
 
#5 ·
If you change the hardware, it is better to change the SW, too.[/b]
In the end, that is exactly my plan. I'm aiming at a Hirsch Stage 3 chip but simply can't afford the full hardware+software package at once. So I was considering to buy the hardware parts step-by-step and finish with the modified ECU. What I understand from the above is that I should wait spending money until I can go for all at once
 
#6 ·
Abbott is not able to make custom ECUs. I am 100% sure of that.

If a supplier states: "This piece of equipement adds 10 hp", the statement is usally wrong.

For example, my car:

MapTun stage III Viggen 285 hp
Race Cat instead of Sport cat + 5 hp
Larger Intake pipe + 5 hp
Very large Race intercooler + 10 hp
Gas flowed head + 15 hp
Fine weighed pistons, fine balanced crankshaft + 5 hp

Total: 325 hp

Dyno result with MapTun Stage III 269 hp
Dyno result with Hirsch Custom ECU 280 hp

Limiting factors are the turbo and the fuel injectors. I could probably get more hp raising the fuel pressure (Vigge´s Viggen, which is quite similiar to mine minus the gas flowed head, dynos 290hp with stock turbo but uprated FPR), but I am driving high Autobahn speeds for longer distances, so this would put to much stress on the turbo. To get more power than I have and still have a reliable performace, I would need a larger turbo - which would introduce more turbo lag.

The Mitsu TD04HL-15T will not support more than 280 hp for a longer period, just for short peaks.

Yours,

Philip
 
#8 ·
Originally posted by Hanm:
[qb]What I understand from the above is that I should wait spending money until I can go for all at once      [/qb][/b]
Basically, yes - but as I pointed out, adding the big downpipe plus racecat (plus cat back system) as the first modification might work for you. It just won´t give you much more power without the proper ECU programming. It will improve turbo spool up, though.

Although Hirsch was not impressed by my JT exhaust (they called it a "cheap exhaust"), I quite like it. It is cheap, does the same job than the much more expensive stainless steel systems (which, admittedly, will last longer and look even better) and sounds gorgeous.

Yours,

Philip
 
#9 ·
Originally posted by MarkA (Saab 'M-F' 9-3):
[qb]As ever Philip, an excellent post. Off topic : what the heck are you doing in bosnia? [/qb][/b]
Thank you very much. Regarding my "short trip to Bosnia" (I will be there until the middle of September), I´m on a NATO peace keeping mission. Of course, I won´t go into details on a public forum, but I will get back to you tomorrow via PN. Sadly, I had to leave my Saab at home. Driving around in the Bundeswehr´s Mercedes G-model Jeep is already annoying me
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Yours,

Philip
 
#10 ·
Originally posted by philip hs:
[qb]Abbott is not able to make custom ECUs. I am 100% sure of that.

For example, my car:

MapTun stage III Viggen 285 hp
Race Cat instead of Sport cat  + 5 hp
Larger Intake pipe + 5 hp
Very large Race intercooler + 10 hp
Gas flowed head + 15 hp
Fine weighed pistons, fine balanced crankshaft + 5 hp

Total: 325 hp

Dyno result with MapTun Stage III 269 hp
Dyno result with Hirsch Custom ECU 280 hp

Philip [/qb][/b]
Hello, I'm new in this forum but already know personally some of the members.
I only wanted to "correct" some data posted here as I have the printout of the bench where this car has been dynoed:

Dyno result with Maptun Stage III 178kW at approx 4500rpm
Dyno result with Hirsch software 206kw at approx 5600rpm

This values are uncorrected power at the flywheel on a Bosch FLA203 bench.

So the powerdifference between MapTun and Hirsch Sw on the same car, same day is not 11 HP but nearly 30 kW and a huge rpm difference.
Would like to post this Dynoruns but I dont know how to do it.

Trionic
 
#11 ·
Originally posted by philip hs:
[qb]Changing to a 3" exhaust + race cat can cause a CEL to light up with stock software. This info is confirmed by Fredrik of MapTun. Same goes for a big intercooler on stock software.

I had loads of hardware mods with stock software, and no CEL. Car seamed to run fine, but the dyno curve was very bumpy, there was not really much more power gaoin over the unmodified car and Tech reading showed down-adaptation by the ECU.

If you change the hardware, it is better to change the SW, too.

Yours,

Philip [/qb][/b]
One of the first things I was going to do when I get my 9-5 Aero soon, would have been fitting the full JT 3" system + d/p + sport cat with possibly the high flow intercooler.....

In light of the above....perhaps not now
 
#12 ·
Originally posted by Trionic:
[qb]I only wanted to "correct" some data posted here as I have the printout of the bench where this car has been dynoed:[/qb][/b]
Do you mean my car? Please explain how you got the printouts? Did you break into my house?
The Dyno runs I am refering to were on May 27th 2004 at Heisel Motorsport in Merzig, Germany. The MapTun Software dynoed 198 kW and not 178 kW (better to compare the whp, as they are not corrected: 228 whp MapTun vs. 243 whp Hirsch).

While I was at Hirsch´s place, I did not have the MapTun ECU with me, so there was no comparison possible.

If you want more detail, please have a look at http://www.saabscene.co.uk/ubb/ultimatebb....pic/23/850.html

Yours,

Philip
 
#14 ·
It is a little off-topic, but here it is

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Yours,

Philip

P.S. It is in fact not very fair to compare these two graphs, as the MapTun software is a standard Stage III program, which is not aware of the changed intercooler and cylinder head. MapTun offered to make a Custom Program, too, but I´m very happy with the Hirsch program and not yet sure if it is really worth the travel from Germany to Sweden: MapTun might reach higher peak power, but the Hirsch program is very nice to drive and "playing it safe" for the engine.
 
#16 ·
Let me also take part in this conversation since my car mentioned above by phillip.
These results have been posted before, but I'll do it again just for remainder. I have the same mods on my viggen (parts also, exhaust and IC) as Philip does, FPR is extra and no gas flowed head. SW by Maptun
 
#17 ·
Of course all of this is very very slightly off topic.

I think the question is how the stock software would adapt, wasn't it?

Nicholas Taliafferro managed 230 whp on completely stock software with a larger intercooler, 3" downpipe, and BSR intake (I think).

Since the car dyno's at 212-214 whp stock, I think it would be fair to say he gained some whp from the modifications. Downpipes, intercoolers, and intakes don't make much hp on their own on most turbo'd cars. So the gains make it look like the stock ecu can manage them just fine.

I think many modified ECU's use a set-unadaptive program for the wastegate duty cycle. This has been the case in nearly any piece of aftermarket software I've seen. Very rarely are they as adaptive as the factory setup. The factory setup has to be able to deal with different conditions, wear and tear on turbo parts and other engine parts, and varying fuel grades.

If anyone has bad experience with the factory software they could prove me wrong, but I think the factory Saab setup is probably a bit better at adaptation than most aftermarket setups.

Here is a link to Nick's stock and stage 1 SpeedParts dyno chart. The stock is blue.

http://www.genuinesaab.com/dyno/Charts/Gra...ck%20chart.html

And here's a link to my stock dyno chart.

http://img5.photobucket.com/albums/v14/SaabTuner/211-206.jpg

The difference between mine and Nick's is about what I'd expect from the stock T7 software. The line remains fairly smooth. Then he goes and instals a SpeedParts stage 1 ECU, and because he is not at a stage 1 setup, it doesn't net much more hp over the stock ECU with his modifications.

Anyone have any different experiences with the stock software?

Dubbya~
 
#18 ·
Originally posted by Adrian W:
[qb]If anyone has bad experience with the factory software they could prove me wrong, but I think the factory Saab setup is probably a bit better at adaptation than most aftermarket setups.
[/qb][/b]
Yes and no.

1 - Stock software is better than those setups that don´t adapt or try to gain hp by tricking the engine by faking sensor data. Hirsch software keeps full adaptation possibilities.

2 - On modified hardware, the stock software will always adapt down (we already discussed that in the other thread). On longer high speed runs or on bad fuel, it has not much room left for further down adaptation, which may cause trouble, if you know what I mean.

Yours,

Philip
 
#19 ·
Originally posted by philip hs:
[qb] QUOTE
Originally posted by Adrian W:
[qb] If anyone has bad experience with the factory software they could prove me wrong, but I think the factory Saab setup is probably a bit better at adaptation than most aftermarket setups.
[/qb][/b]
Yes and no.

1 - Stock software is better than those setups that don´t adapt or try to gain hp by tricking the engine by faking sensor data. Hirsch software keeps full adaptation possibilities.

2 - On modified hardware, the stock software will always adapt down (we already discussed that in the other thread). On longer high speed runs or on bad fuel, it has not much room left for further down adaptation, which may cause trouble, if you know what I mean.

Yours,

Philip [/qb][/b][/quote]I hardly think it's fair to say that the software will always adapt down given some of the experiences of different people.

Probably going to rock the boat a little here, so bear with me.

Hirsch claim that the stock software always adapts down. Hirsch are also trying to sell you modified software. Even if they tell the truth in every case, there is a conflict of interest in relying on their word alone.

People who've done back to back dyno runs with the stock software using modified hardware claim that the stock ECU works just fine. They are also trying to show off the parts they just bought. Same conflict of interest.

So far I haven't really heard any reasons behind either line of reasoning.

If the stock ECU learns down, maybe sometime someone could get Hirsch to give an explanation to why.

If it learns up I'd like to see some explanation for that. (Aside from the usual reasons that are generally asociated with hardware mods.)

I personally am a little skeptical of the car learning down. It definitely learns up when you put some good gasoline in it.

I also think some hardware modifications could cause trouble. For instance a 3" exhaust and intercooler will significantly increase the VE of the engine. When the engine switches to MAP mode at WOT it will be using the stock VE as reference and could consequently run slightly lean-er and on poor gas this slight difference could case detonation, which would cause boost reduction and timing retard. IE, learning down.

But in the latter case, given sufficient octane, there wouldn't have been detonation, and a leaner mixture would have generated more power, rather than less. (Since the difference would be relatively small, perhaps from 12.5:1 to 13:1. Nothing drastic.)

Also a 3" exhaust can cause boost creep. It tends to raise the base boost, and few people adjust the base boost when the receive a new exhaust. So now instead of say 8 psi, it's 10 psi, and the computer can no longer drop it below 10 psi even if there is detonation from the leaner mixture and heat soaked intercooler at 120 mph on the autobahn ... you get the idea.

Buuuuut ... does that mean that the stock software learns down? Or does it mean that the modified hardware was not properly designed for the stock software?

Seen some evidence both ways. And don't just consider T7 cars. T7, as mentioned before, works very similarly to T5 at WOT. Those same changes to VE will affect T5, though perhaps in a different way.

If anyone has any qualitative reason why T5 would adapt up (which has been seen in nearly all cases) and T7 down, that would be most helpful! So far it seems to be a bit of a mystery.

Not that I'm comaplaining. I rather like the T7 stock software and hardware.
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Any other ideas?

Dubbya~
 
#20 ·
Originally posted by Adrian W:
[qb]Hirsch claim that the stock software always adapts down.  Hirsch are also trying to sell you modified software.  Even if they tell the truth in every case, there is a conflict of interest in relying on their word alone.
[/qb][/b]
I think you're bordering on the slanderous with that statement.

Can you actually recount documented cases of Hirsch not telling the truth or as having a conflict of interest?

Hirsch are the only Saab factory recognised tuner right now. Also, when it comes to trionic mapping, not only do they have complete access to Saab's documentation - they also have access to Saab's trionic development team, as is evidenced by the Saab factory trionic engineer present at Hirsch's when Philip's car's software was being custom written.

As is seen here :

http://www.saabscene.co.uk/cgi-bin/ultimat...pic/23/850.html

So given they have full cooperation with the Saab Factory, how can there be a conflict of interest?

And given that their access and knowledge of the subject (as evidenced by the fact that they actually write trionic software for a living) results in a defined working certified product, rather than some debatable anecdotal theories and experiments you have presented, might Hirsch actually be correct?
 
#21 ·
I think in order for it to be slanderous I would need to have left out the "even if they tell the truth in every case" ...

I'm simply trying to be objective. Trusting someone because they have experience and factory backing is wise. But it is not the measure of the putative truth.

Suffice to say had I the money, they would be my tuner of choice. But that doesn't mean I believe they are incapable of mistakes. They can "tell the truth in every case" and still be wrong about what they believe the truth is, even with experience, and even with factory backing.

I'm not saying that they are wrong. They may very well be right.

The ENTIRE point of my message, was to bring forth evidence to support claims either way. Not to discredit any particular tuner and anything they've said.

Like I said, I may be rocking the boat a bit. But that's a far cry from slander.

Then again, Gallileo died for "rocking the boat". Maybe I should re-think my past-times.
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Remember, I LIKE Hirsch, I just want something more scientific than "we say so". That's all.

Dubbya~
 
#22 ·
Originally posted by Adrian W:
[qb]If the stock ECU learns down, maybe sometime someone could get Hirsch to give an explanation to why.  
[/qb][/b]
I think I did so multiple times - see the other thread. But I will repeat what I wrote for you once again:

In theory, Trionic will adapt to your driving style. So if you perform the famous adaptation run, it should adapt up. If you use better fuel, it should adapt up, too.

But the stock software was calibrated for the stock hardware. If you change the hardware without changing the software, calibration will be off, the engine´s sensors will read different values from what the ECU expects and therefore it will adapt down in most of the cases (to protect the engine). If the readings are too far off, the CEL will light.

Sounds convincing, doesn´t it?

Yours,

Philip

P.S. The first step in good (custom) chip tuning is calibrating the ECU to the modified hardware. This will already yield huge increases in power, without putting any additional strain on the hardware - in fact it will even reduce strain. From that point, you can start playing with ignition advance and boost control.
 
#23 ·
Originally posted by philip hs:
[qb] QUOTE
Originally posted by Adrian W:
[qb]If the stock ECU learns down, maybe sometime someone could get Hirsch to give an explanation to why.  
[/qb][/b]
the engine´s sensors will read different values from what the ECU expects and therefore it will adapt down in most of the cases (to protect the engine)[/qb][/b][/quote]Now that sounds more like what I wanted to hear. But then it begs the question, why not in all cases?

In some it clearly adapts up. There must be some difference involved. And why doesn't T5 adapt down? Or does it? ERP ran for quite some time on the stock software, and while his modified software gave more power still, he certainly didn't lose power on the stock software. T5 also adapts.

Is there a concrete and qualitative difference between T5 and T7 adaptation which Hirsch quoted? Could the reason the same reason that some adapt up, and some down. Some perhaps not at all?

And Phillip I certainly understood what you said. It was quite well written.
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But it does leave serious gaps. Adaptation is not unique to trionic 7. Sometimes it adapts up. The explanation isn't quite complete.

Given the exorbatant cost of a software upgrade, it would certainly be nice to know which hardware modifications T7 will tolerate, which it will like, and which will harm it. Suffice to say it's impossible for every hardware mod to hurt it. Otherwise it would adapt down every time variables changed due to wear, engine age, climate etc ... and this does not happen.

I can see T7 adapting down to stock despite hardware modifications. That would make sense. But your dyno charts indicate adapting down below stock. (Or did I miss something?)

Perhaps we can find out where the boundary lies, and be careful not to cross it. It'd certainly be nice to know, and I believe it was the intent of this thread to find out. (Though at least partly my fault for getting off topic. All apologies!)

Dubbya~ (Painfully earning the nickname, err ... again I mean.)
 
#24 ·
I am not entirely sure on the reference, but I do know that the T7 cars will adapt to a manual boost control on the stock software. Everybody who has tried a mbc on a T7 reported that the T7 would notice the extra boost and then use the electronic throttle to control the amount of air going through the MAF and engine to match it's expected values. This is a well documented case of the T7 adapting down.

As for adapting up, most likely, when it does adapt up, it was probably from settings that it had adapted down to from bad gas and such.

So as far as I know, there is not much to be gained on a T7 Saab until the software is modified to fix this MAF value the Trionic looks for. I believe I saw this on Alldata. I'll do some further research and get back to this.

Oh, by the way, the T5 doesn't have the MAF and the torque control feature that I described on about the T7 in this post. That is why the T5 can respond quite well to a mbc and gain more power from other hardware mods that increase flow. The T5 is happy provided there is no detonation and the set boost/fuel cut level is not reached.
 
#25 ·
When comparing the T5 and 7 we need to remember that the other (T5) is a speed density system and the other an airmass controlled one. The T7 will "boost" to target airmass asked by the ECU.
Airmass is cotrolled by throttle mainly and turbo control, which takes ower when throttle control can no longer do the job. So, no matter what you do the airmass cant be added with out touching the SW also. Well some benfit can be gained through un correct operation of the airmass control. On the other hand mods might as well have the opposite affect, when the system operation is no longer optimal, thinking from the ECU's side.
The speed density system on the other hand will boost to a set boost value asked by the ECU. It does not take very long to figure out what a better IC will do on a car like this one. Same boost lower intake temp = more airmass = more power.
 
#26 ·
Great! I was preparing an answer for Adrian, but Vigge, you said it all. One might add that a Trionic 5 car has 3 maps, while Trionic 7 has over thousand. Trionic 5 does not take advantage of lower outside temperatures or higher air pressure, max boost (by SW) is always the same. T7 has different maps for all working conditions. That´s why a T7 car offers much more reliable (and smoother) power.

Yours,

Philip