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Discussion Starter #1
anyone know the base and max boost for the speedparts stg1/2 ecu? i got a figure of 17psi on saabnet...

also, thoughts from others that switched from a MBC to the ecu? did you lose much low-end boost? i hate to give up the quick boost that the MBC provides...did you try to run the MBC inline with the BPC after installing the ecu?

thanks for the input

eric
 

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Welcome to the Board, ericl.

I think you'll get a better response if this message is moved to the Saab Turbo Team Europe forum.

Martin
Saabscene Staff
 

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Base boost won't be effected by the Speedparts ECU as it is controlled by the wastegate setting. My 9000 boosts at 1.1bar (+/-16psi IIRC) with Speedparts stage 1: at a guess the 9-3 would be a similar level.
 

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My SQR stage 3 was 18 psi under ECU control, with a MBC I could hit 21 psi. I have done a bit of testing and I do not recommend using just a MBC to control boost, the upper rpms do not perform properly. I have come up with a Dual Stage Boost Controler setup that works very well.

Recently I have begun to experiment with the wastegate length. With help form ckpaden it appears that boost taper at higher rpm is caused by an underpowered wastegate. With the SQR ECU and stock wastegate boost would decline to ~16 psi by redline. Now that I have shortened the wastegate I can maintain 19 psi to redline. I still have more work and tests to do but it looks like I can finally get rid of the annoying boost fade.

Eric
 

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In my 9-3 w/Speedparts Stage 2, the highest boost I've ever seen was just over 19 psi, fading to between 14.5-16 by redline, as ERP also reports for his 900.

ERP - are you not worried about damage to the turbo or other engine components when maintaining peak boost to redline? I've read several places that Saab built in that taper specifically for an engine safety parameter.
 

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Originally posted by Jason (Mr Torque-Steer):
[qb][I assume he means the wastegate actator rod? [/qb][/b]
Undoubtedly... for more info on how/why this works, see here for my earlier rantings

FWIW I also think you're playing a dangerous game Eric running that sort of boost to redline. Your turbo will be out of it's efficiency zone, running very hot, and I doubt that standard injectors will be able to flow enough fuel to control the likely detonation. Not only that, but the APC will probably also be out of mapping range and thus not able to control the iginition timing properly. I don't want to pee on your bonfire, but I'd at least try to borrow a Tech 2 to take some readings from the knock sensor...
 

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Discussion Starter #10
nice, thanks for the great replies/feedback everyone...nice to see you on this bb also ERP!! the saabnet crew is missing the great insight from a true enthusiast!!

so i checked on my speedparts order today, should be 10 days or so....i also have a viggen IC coming along with it, and will be taking advantage of the great idea that ERP has posted on his site to forego the purchase of the inlet hose (saving 100$US) and using the aluminum cross section to lengthen the hose....

i just got the car back after having a viggen clutch installed and switching to mtf0063 synthetic gear oil, and the new linkage upgrade...now its time to put it to the test!...

i have checked out the dual-stage and it looks great..will probably try just running my dawes device inline with the BPC also, but only if i miss the quick spoolup it provides...thats one of my fears switching to the ecu from the mbc....from what i've heard, you just can't beat the spoolup that the mbc provides...!!

thanks

eric
 

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I feel like I am in a support group,
“Hi, my name is Eric and I have a problem. I can’t get enough boost.”

Seriously though I appreciate your concerns and I do not recommend that others just blindly crank down their wastegate. I am achieving the high pressures with the ECU controlling boost. I can see the APC regulating boost all the way to redline. I also have an exhaust temp gauge, air/fuel gauge and an intake temp gauge to monitor things. For turbo protection I use Mobil 1 15W-50 Synthetic, designed for high performance turbocharged engines. And most importantly I am using water injection. Currently it is only a 0.7mm nozzle but soon I am going to get a second nozzle and make a two-stage water injection system.

Bill, I have a 2.0 engine making 262 ft-lbs at 3100 rpm. But I was using a MBC during the dyno test which limited max power to 214 wheel hp. Now with ECU control there is a substantial increase in top end power and I want to get my Saab dynode again.

Thanks for the complement ericl but I will never post on SaabNet again, glad to see you over here though. Sound like your Saab is coming along nicely. Speedpatrs ECU and the Viggen Intercooler will make a nice improvement.
Enjoy,
Eric
 

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Yeah, I had an Abbott MBC before I could afford the ECU, and the spool-up was definitely faster, giving that harder kick in the back. But I can't say I'd go back to it if I had to choose, the extra 45 hp is awesome Might try to hook myself up something like the dual-stage system that ERP designed.
 

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Originally posted by ERP:
[qb]I feel like I am in a support group,
“Hi, my name is Eric and I have a problem. I can’t get enough boost.”
   
[/qb][/b]
LOL, ERP

Originally posted by ERP:
[qb]Thanks for the complement ericl but I will never post on SaabNet again, [/qb][/b]
What's SaabNet
 

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originally posted by /John:
 What's SaabNet  [/b]
Good question!
Saabnet happens to be a site that whenever you post a message that includes the word SAABSCENE, your post gets deleted. I have e-mailed the webmaster to complain about that. But being a US based site, patriotism goes beyound good manners .
 

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first there was too many mark's
(remember that thread entirely made by the mark's
and now erics's...oh dear I think I need to lie down
 

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Good to hear about the water, Eric (ERP), however whilst increasing the amount of injection will help to control detonation, it will also lower your available power, becasue, put simply, water doesn't burn!!

On my dyno run the other week, I saw abut 302hp (corrected) at the flywheel with water injection, and 311 without.

If you want to maintain higher boost levels, then I'd seriously recommend a bigger turbo (which will run cooler) and bigger injectors with appropriate mapping. This is what I've done.

Also, rather than keep winding the wastegate in, you're better off going for one with a stiffer spring to start with.

Keep up the good
!
 

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Mark, I had similar results when I dynode my Saab. Without water wheel horsepower was 214 hp and with water it was 210 hp. I am using a 30% Isopropyl Alcohol and water mixture. I did some testing in this is about the highest percent of Isopropyl before it ignites. I don’t want the possibility of it burning inside my water pump, otherwise I would use a 70% mixture.

I would love to upgrade my turbo and injectors but I am on a college budget and can not afford anything big. I am looking into an upgraded wastegate but they are tough to find, not many places sell them.

Eric
 
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