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Discussion Starter #1
That's right. Using a MBC and spiking to 28 psi gave me 318 ft-lbs of torque. Unfortunatly the turbo can't hold the high boost for very long and it drops to 18-20 psi and 250 ft-lbs. But I put down good hp numbers again, 230 whp was repeated for three of the four runs.

I did four runs on the dyno with air/fuel for all of them. Because of the direct injection the rpm sensor for the dyno had problems. The torque above 80 mph, which is 5000 rpm, was not recorded correctly. It looks like something is really wrong but the torque actually falls off smoothly, which is indicated by the flat horsepower curve.

The air/fuel ratio looks good but not much more horsepower can be safely produced without upgrading the fuel system. My last dyno used a crushed fuel pressure regulator but the torque curve was down 10 ft-lbs. I will need to upgrade my injectors and software if I plan on any more large hp gains in the future.

For the full write up and all the dyno sheets check my website. http://www.lehigh.edu/~erp4/Dyno4.html

Below are runs 2, with ECU control, and run 4 with MBC control.
 

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318 ft-lbs How much is that in NM? i'm just curious cause at the dutch rr day. I saw i same kind of peak on maarten's 900 hirsch with td04. He had a peak torque of 474 NM so just for comaprisation.
 

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Originally posted by ERP:
[qb]Because of the direct injection the rpm sensor for the dyno had problems. [/qb][/b]
You mean direct ignition, right?

Nice result , and the spike indeed looks quite similar to Maarten's. Stupid thing is, he had the same kind of spike with boost fully ECU-controlled, and you didn't when reverting back to non-MBC operation.
 

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Originally posted by Injectie:
[qb]318 ft-lbs How much is that in NM? i'm just curious cause at the dutch rr day. I saw i same kind of peak on maarten's 900 hirsch with td04. He had a peak torque of 474 NM so just for comaprisation. [/qb][/b]
318 lb ft is around 431 NM.

Went and checked out the full writeup ERP. I think the trouble with water injection might have been how close your injection nozzle is to the engine, and the use of washer fluid. If any droplets get into the spark plug gap before it normally fires it will cause the ECU to think there is pre-ignition. And I think the washer fluid makes it more difficult for the water to fully evaporate into the air.

It detects pre-ignition and detonation the same way. By measuring the current flow across the gap when the plug is not being fired. If there is any current from water droplets before the plug should be fired that's perceived as pre-igintion. After the plug fires it detects detonation by appying a 6,800 Hz bandpass filter to the IGS sensor's signal.

Anyway, love the graphs! And 18 psi is not low at all. Heck by redline I'm down to 11-12 psi. Darn factory boost taper!

Dubbya~
 

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Discussion Starter #6
Originally posted by Eric van Spelde:
[qb] QUOTE
Originally posted by ERP:
[qb] Because of the direct injection the rpm sensor for the dyno had problems. [/qb][/b]
You mean direct ignition, right?
[/qb][/b][/quote]Oops, yes I mean direct ignition.

Nice numbers Vigge.
 

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Originally posted by Eric van Spelde:
[qb]Nice result           , and the spike indeed looks quite similar to Maarten's. Stupid thing is, he had the same kind of spike with boost fully ECU-controlled, and you didn't when reverting back to non-MBC operation. [/qb][/b]
The extreme torquenumber was caused by a boostspike. The first dynorun that day did not have the spike, torque was 423Nm. If the humps in the torquecurve at 3000 rpm are flattened, the engine wil probably produce 400Nm.

There's some boostpumping around 3000 rpm. Eric B. had the same problem, it turned out to be a faulty acuator. After fitting an uprated actuator I'll dyno the car again to get some more reliable figures.


Good results, Vigge and Eric
 

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What were the at the wheels numbers? Curious what they used for the drivetrain correction. Looks good though.
Custom software and an intercooler should make the car much more consistent.


Dubbya~
 

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Originally posted by Adrian W:
[qb]What were the at the wheels numbers?  Curious what they used for the drivetrain correction.  Looks good though.    :fawlty:    Custom software and an intercooler should make the car much more consistent.    :thumbsup:  

Dubbya~ [/qb][/b]
Losses are calculated from the down run after each pull. I do not have the wheel number in hand.
 

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Looks awesome nonetheless.
Who did the custom software? I think it's really cool that they were able to keep the stock curve shape. I made a comparison to my stock Viggen using a 15% drivetrain loss. Some places have shown as much as 18% for Saabs, but I thought 15% was more reasonable. That puts mine at 251 hp and 401NM at the crank. Here's a comparison showing how similarly the two graphs look:

Definitely a very nice set of power curves. And looots of torque.


Dubbya~
 

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Nice figures Vigge
. But how does the car handle on an actual road? If for instance you are changing from 2nd into 3rd gear, you are likely to be in the 2000 to 3000RPM range when the XXX(expletive deleted) hits the fan. Having been there and ended up remapping my ECU to take a way that "death wish" region, I am very curious how you get around the problem. VRK, modified suspension? Let me know please.
 

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Originally posted by StanleyB:
[qb]Nice figures Vigge  
     :thumbsup:   . But how does the car handle on an actual road? If for instance you are changing from 2nd into 3rd gear, you are likely to be in the 2000 to 3000RPM range when the XXX(expletive deleted) hits the fan. Having been there and ended up remapping my ECU to take a way that "death wish" region, I am very curious how you get around the problem. VRK, modified suspension? Let me know please. [/qb][/b]
To be honest the car behaves like [expletive deleted], but there is no need to worry since my suspension/ body mods are still to come. With my previous car I started from suspension and worked my way up to the engine, but with the saab I was temptated to the the other route. Anyway right now the car is almost ony suitable for stairt driving if you want to push the pedel to the metal.

The sofware is mapped by Maptun and changes where planned even before these runs. So this is our start point, from which modifications to my needs will be made. I havent decided yet what I what, but the "death zone" needs to go since its not to healthy for clutch and tranny.
I think I want to flatte the curve out between 2500 and 4000. This is not decided yet, but some changes along those line will follow.
 

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originally posted by Vigge
 I havent decided yet what I what, but the "death zone" needs to go since its not to healthy for clutch and tranny.  [/b]
Absolutely spot on . Been there etc...

 I think I want to flatte the curve out between 2500 and 4000. This is not decided yet, but some changes along those line will follow.  [/b]
Pitty you aren't close by in order to try my car. With the 2000 to 3000 violence now tamed, power is now better controlled. I don't get any of that Viggen "dancing with reindeers" kind of feel from the front wheels anymore. I honestly recommend you put that ECU map mod on the top of your list.
 

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Originally posted by StanleyB:
I honestly recommend you put that ECU map mod on the top of your list.[/b]
This whole ECU thing is one big project and it has been active for a while now. Since Maptun is not located in my back yard, it is not that easy to do wanted modifications, when you cant drive your car there.

Eaven though the work is not finnished, I want to thank the Maptun guys, especially Fredrik, who has made this arrangement possible. They have been very helpful. The next step now, is to send all the date to Sweden and then plan modifications to gether. Since I knew in advance that there will probably be a need for changes, I took out a lot of info from my car when it was on the rollers.
Besides the dyno software readings, we connected a tech to see knock, airmass, timing etc.
With all this info it is easier to make the mods you want.
 

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Originally posted by philip hs:
Oh, I want one, too! Or should I get the Hirsch unit?

How much did it cost you to have it made?

Yours,

Philip[/b]
-IC 450 Eur
-installation 180 Eur

Normal price is 200Eur or so more, but I got a really good deal through a group buy
 

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Originally posted by Vigge:
[qb]IC 450 Eur
-installation 180 Eur

Normal price is 200Eur or so more, but I got a really good deal through a group buy       [/qb][/b]
Oh, I´m so envious! Couldn´t you get me one for 450 and send it directly to Heuschmid? The Hirsch IC he is going to use on my car will be 800 EURO at least...

Yours,

Philip
 
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