00 9-5 areo hp increase [Archive] - SaabCentral Forums

: 00 9-5 areo hp increase


9-5ecopower
30th September 2003, 06:29 PM
Hi, im Alex I am new to the forum, I am in the process of getting a Black on Black 9-5 areo 5spd with BBS wheels. I was wondering if there was anything I could do, moderatly expensive and easy, to inprove the 230 hp :cheesy: . Not to say that 230hp is bad in any sense. I just want to see what my options are and if this is feasable.

PS
I just want to say that this is the best forum i have been able to fine so far. I have gotten so much info just by reading through the posts. You guys are awsome. I will get some pics of my car when i get it to share with all of you. Thanks so much.

Alex

Simon
30th September 2003, 06:50 PM
Welcome to Saabcentral.

There are ECU upgrades available from various companies in the USA such as BSR, Nordic, Maptun etc.,

www.genuinesaab.com

www.wigwamsaab.com

www.group9performance.com

9-5ecopower
30th September 2003, 07:32 PM
thanks, do you realy feel that they are worth it. Will i feel much a diference in pick up and acceleration? What would you say i do to my stock 9-5 areo? I want as much input as i can get

murphwiz
1st October 2003, 01:28 PM
Welcome to saabcentral!

The actual 0-60 of your Aero won't feel that much quicker, but with something around a 40bhp increase, along with the torque increase, you could expect to cut 2 seconds off your in gear times... :cheesy:

DrBoost
25th January 2004, 12:01 PM
Hi !

Increasing the maximum power of a B235R "Aero" is NOT recommended UNLESS you do something about the breathing of the engine. So called "Step 1" kits, where you get s/w and possibly a cotton airfilter are not recommended.

IF you fit a free flowing exhaustsystem and a few other mods. then it's a different thing.

What you usually experience on Step 1 Aero kits is an increament of torque in low mid rpm range.
Maximum bhp is more or less the same, sometimes less....

Stumpage
26th January 2004, 01:00 PM
I have a March 2001 Aero 230bhp. Same as the picture on the left Black with Black interior (Fine choice Sir) 8) .

The thing you will notice is how hard it is to keep the power down without the TCS flashing at you. You will find the car is plenty fast enough and will overtake quicker than most in stock form. So basically if you want to upgrade the power then be prepared for very regular front tyre replacement. :cry:

XAAMOTTOMAAX
26th January 2004, 09:05 PM
Dr. Boost,
Can you explain the potential negative effects of increasing max power on the Aero? I have a stage 1 ECM, high flow air filter, forge BPV and increased diameter pipe going from intercooler to throttle body. Should I rush out and get a higher flowing exhaust system and if not, what potential problems could I face?
I have heard the name "Dr. Boost" but thought you were only alive in bedtime stories and legends!
Thanks!

DrBoost
27th January 2004, 03:13 AM
Hi !

Sure, I just can't say, NO, I will have to explain....

So, here it is:
Since more than 100 years now, it has been known to man that if you want to increase the power from an internal combustion engine such as the engine in a Ford Model T or a 9-5 Aero the engine needs to breathe deeper.
Right ?
Yes !

So, for the Model T there were many tunig kits, OHV-conversions and so on....
I belive it's the same today, with the vars we have today, but slightle different, today we can increase the breating by software, within some limits.

Analyzing the 9-5 Aero, tells us where to modify.

Induction side:
* Air supply to airfilter box.
* The "cobra tube" (the cast aluminium to turbo inlet)

The two above is probably step #1.
The tube between I/C and throttlebody is not "a problem" the stock (plastic) tube is being used on the 305 bhp/420 Nm kits, "Saab Performance by Hirsch". But the two I mentioned above has been replaced....

As step #2 I would vote for a better I/C.

And of course, the exhaust side needs some attention....
Stock exh. system (cat back) is restrictive, for increased power. As step #2, you need new cat a free flow exh. system.

And, finally, turbocharger:
The MHI TD04HL-15T-5cm2 is a fine unit, but for power levels above some 270-280 I STRONGLY SUGGEST that you do something about it..... First, the turbine area is too small for power levels above 280 bhp. It can be replaced with a 6cm2 turbine housing, the one you'll find on a 9k Aero.

So, the stock Aero h/w needs a few mods before you can increase the power. If you do not do this, the result can be:

* Exhaust temperature faar above specs.
Possibly damaging turbo, exhaust manifold, exh. valves, or causing a fire.

* High thermal stress for the engine, prone to knock, broken pistons.

* Over reving the turbine.

BUT, h/w mods often require s/w mods.
DO NOT do h/w mods before consulting your tuning supplier.

nivlak
1st February 2004, 10:01 PM
I have no idea what he just said but man, it sounds like he knows what hes talking about :D

XAAMOTTOMAAX
1st February 2004, 11:12 PM
simply put...the intake pipe and the downpipe/cat/exhaust are the areas of most restriction when the ecu is modified. changing the ecu program to run at a higher power level without opening up the breathing of these two pieces can result in the negative affects he described. therefore these parts should accompany any ecu upgrade for optimum tuning and reliability.

kamalk
25th February 2004, 02:46 AM
Ya that's all fine & dandy. But what type of "high thermal loads" are we talking about? as long as the right quality of gas and oil are used and if your pistons have broken or melted because of an ECU upgrade then you really should not have purchased such a poorly designed product to begin with. I mean it's one thing if somebody is going to drive the car very hard on a race track in 90 + degree wheather but as a regular daily driver that will see short bursts of full throttle applications only I really can't see how a "fire" might occur as mentioned by "Dr. Boost"
That said, I certainly do agree that upgrading the intercooler will help in every aspect.

Mattlach
1st April 2004, 01:09 PM
Withheat being a greater problem after a software only, so called "stage 1" upgrade, I wonder if the common problem of hot turbo oil becomes more of an issue.

How long is it reccomended the Aero idles after hard driving in hot weather, to get the oil temps down before shutting it off again?

thanks,
Matt

DrBoost
9th April 2004, 04:27 PM
Hej !

A few comments:

kamalk>>
Can we argee that a short burst is approx. 2-5 s of full throttle ? What would you say if I told you that I've seen EGT's around some 1800-2000 F during a "short burst".
AND, this is being measured during "road conditions".
This is not acceptable.
I belive that we all agree ?

Mattlach>>
Hot TuRbo oil is not an issue.
As a general rule of thumb, after driving hard, the engine needs some time to cool down, and equalize temperature.
Let's say, typical race track driving, at least one lap of cruising, and then park the car, let it idle for a coulple of minutes before turning off. Or, if the TuRbo is red, do not turn off. I prefer DRIVING (with lo load) instead of idling standing still.

sumfir
30th May 2004, 03:06 PM
I have read, and I understand the arguments of breathing. I have a major complaint. For most of us, these cars our our daily drivers. Our lives with 2.3 children and work schedules dont always permit a couple of grand of mods and the time to perform them. We look for simple modifications that will keep our aging machines current with the performance market.

So answer me this, what modification was made from my 2001 230 HP to 2003-04 250 HP by our friends at Saab and did they involve better air supply and turbo inlet tubes, or as I suspect a remapping of the ignition and fuel delivery via the computer. If they did increase breathing and computer mods then they concur with what is being said in this forum.

If all it was, was a remap and the breathing in the 04 is the same in the 01's then I have to disagree. If Saab was comfortable enough in pushing the extra twenty HP with out heat issues. I cant imagine Saab manufacturing making the changes in HP and not leave a very big cushion. I am in manufacturing and we test things to it maximums then back down to a comfortable level which leaves a safety factor for us. Common sense knows someone out there will exceed our set level and we know that will be ok. It keeps our business safe and the lawyers at bay. Never sell something that would be counter productive!!!!!

I would think that the our friends that create the PPC's would keep in mind the same cushion. They have to relaize that the "Average Joe" would purchase their software and drive it everyday. Can you imagine the complaints and the hits to their business if the consumers cars started melting down. My gosh the lawyers would eat them alive and saying why would you sell a product by itself with out the other modifications, knowing well that their product would destroy the car with out the other modifications. I would think our friends that create the PPC's know exactly what they are doing. They know that of course the modification will shorten life span of componnents, but not a an accelerated level. Most car owners may never experience an issue, and the componnents that fail customers wouldn't supect it had anything to do to the modification. The aftermarket also knows that performance is addictive. The consumer will want more (like down pipes and bigger exhaust) and they probally will have product to give them more.

Mattlach
30th May 2004, 04:53 PM
... Our lives with 2.3 children and work schedules dont always permit a couple of grand of mods and the time to perform them.

Awesome! One litre per child :P

sumfir
1st June 2004, 09:52 AM
Mattlach, I didn't think that anyone would catch that. I was going off an old statistic and found that it was appropriate.

Do you agree with my rant!

Mattlach
1st June 2004, 10:04 AM
Mattlach, I didn't think that anyone would catch that. I was going off an old statistic and found that it was appropriate.

Do you agree with my rant!

I agree with you. I am not sure what the answer is though.

I suspect that the engine and turbo hardware on the 2002 and on are the same as the 2001 and prior, and that Saab only modified the software.

If this is true, I agree with you. if Saab did it, why not?

There may be more to it than that, but I doubt negative sideffects of a chip upgrade, if the chip maker is respectable and known for his work will show up in defects in regular driving.

Maybe if you just chip it and then use the car as a racer it will see the sideffects that Dr. Boost is talking about. But I'd have to say, that the Aero, even stock, probably shouldn't be used as a racer without some upgrades to keep the engine cooler and happy.

Keep in mind though that I am not an expert and what I am saying could be complete baloney. It just seems reasonable to me.

--Matt

sumfir
2nd June 2004, 11:20 AM
I dont want discredit Dr Boost's point to 9-5ecopower request, it comes down to "buyer beware"! Making changes has repercussions and one should be aware. Dr Boost sounds much more knowledgable than myself on the car, but 20 years of manufacturing and lawyers has taught me other lessons. My point is that there is a flip side to his statement and it is "Caveat venditor" (Seller beware)!! Businesses can be held liable for producing and selling a product, knowing that it can damage ones vehicle if not used in conjunction with any other item.

9-5ecopower and ourselves shouldnt be scared to upgrade our computers, we just know now that more upgrades are required in future.

XAAMOTTOMAAX
4th June 2004, 07:43 PM
The 2002 model did not have any changes. The 250hp is merely a function of overboost which was not available on the 2000 and 2001 automatic transmission vehicles. If you look at the torque rating of the auto for 2000 and 2001 it is also lower than the 258lb/ft of the manual. Now that the new 5 speed automatic has the same power as the manual equipped cars, it is marketed with the 250hp engine. Do not take Dr. Boost's advice with a grain of salt. He is by far the most experienced person willing to take time and post his knowledge regarding Saab and Trionic 7 more specifically. If you are going to spend $1000 on a stage 1 ECU tuning a car you most likely spent over $20,000 to purchase (on the used car market), why not drop another $1000 to improve airflow and keep things in balance? High exhaust gas temps are a big area of concern. Keep in mind the exhaust runs directly under the oil pan. If you are overheating the exhaust, it is all going to rise straight to your oil pan. Do a search on engine sludge and then you will know why it is so important to keep these temps low and to use a high quality synthetic oil. You also want to switch spark plugs to the the NGK BCPR7ES-11 (if you go above stock power levels) and change them more frequently. They are only $10 for 4 and it is literally a 5 minute installation. I change mine every 5000 miles because it is cheap insurance.

Mattlach
4th June 2004, 07:49 PM
If you are going to spend $1000 on a stage 1 ECU tuning a car you most likely spent over $20,000 to purchase (on the used car market), why not drop another $1000 to improve airflow and keep things in balance? High exhaust gas temps are a big area of concern. Keep in mind the exhaust runs directly under the oil pan.

The reason I wanted to avoid a "performance" exhaust was that I dont want my car to sound like a riced up honda with a coffee can exhaust.

Are there good replacements that keep the stock Aero's rahter civilized sound?

XAAMOTTOMAAX
4th June 2004, 09:26 PM
The two most popular choices (JT 3" and BSR 2.5") were made knowing the 9-5 will have a different type of driver than a Civic or Integra or even an Evo or WRX. They are going to give you a sportier sound but nothing over the top. You will not hear it very much in the cabin but will be able to tell the difference standing behind the vehicle especially at full throttle. I would not worry about being offensive with either system. They are designed specifically to increase flow without increasing the volume too much.

sumfir
4th June 2004, 10:29 PM
I like to be the pessimist at times because it helps gather as much information as possible. With each post I am becoming more informed. When it comes to upgrades in performance it is critical to learn as much as possible. I unfortunately still have reservations. Dropping an extra grand here and there is easier said than done. I can say that I tend to be a little tight on the wallet. So I want to learn from you all and to hopefully return the favor.

I have run computer upgrades before (not on a Saab) but on other turbo vehicles. Most have been designed to work with "stock" equipment. However, the same manufacturers or dealers of the computer upgrades just so happened to offer more products (ie...exhaust, BOV's, inlet pies etc..) to "enhance the upgrade".

I guess ultimatly I like to search for the the best bang for the buck. I myself spend most of my driving time on the highway. By this time next year my car will have 70,000 miles on it (32,000 currently).

I do want to pick up a little performance, but dont want to change stock exhaust with a performance one unless I know that the decibel levels are the same or less. I often have customers in my car and noise is bad.

I look for the best advice. Would I be a good canidate for a specific upgrades, or would someone suggest I leave my car alone after knowing the mileage this car will see. Has anyone had a catastrophic failure after upgrading the computer and not upgrading any other componnent?

XAAMOTTOMAAX
5th June 2004, 09:56 AM
It is hard to say exactly what will happen but it is known there are plenty of people running a stage 1 for long periods of time with no problems. Does this mean things are within acceptable safe limits? Not necessarily. Perhaps it is a sign of the strength and durability of the car. Just make sure you keep in mind that the stage 1 is going to strain things much more than a stock engine or even a car that has been tuned with better breathing. Breathing is absolutely critical in tuning a turbo car not only for power but for reliability and durability. There is not a performance exhaust available that will keep sound equal to or less than stock levels.

sumfir
8th June 2004, 10:44 AM
Thanks for the input XAAMOTTOMAAX. Until there is sufficient information it sounds like at this point, engine performance mods may not be in my future. I do believe that a stage one upgrade alone would work for some. However with the mileage that I am putting on this car I feel that the risk may be greater.

With performance mods for Saabs, I dont see much info. I would like to see decibel readings for the available exhaust systems verses stock. Does anyone offer that kind of info??

When I used to play with a German car manufacturer, some of those performance companies were very thorough on their research and provided reams of info including decibel level info. If the manufacturer did not supply the info, a publication would provide perodic tests of aftermarket info which were very useful. We need a Saab magazine!!

Adrian W
27th September 2004, 10:23 AM
There are some things in this thread I agree with, and some things I disagree with.

Apologies in advance if this gets overly technical. I'll summarize it at the end. The stuff between is for the techies and pedants here.

Firstly, a turbocharged engine should not be thought of in the same manner as a naturally aspirated engine. A turbocharged engine is an efficient hot gas generator for your turbine (the turbo). As such, it behaves very differently to a naturally aspirated engine. (It is a system of pressure ratios, thermal management, and timing.) So any analogy made to a T7 engine and a Model T is going to have some inherant flaws.

Secondly, breathing modifications are good, but don't let yourself think that they make any significant horsepower on a T7 engine. Breathing modifications alter the Volumetric Efficiency of the engine. But remember, this is a turbocharged car, not a naturally aspirated one. Whether or not this change in Volumetric Efficiency makes power will depend on the way the turbine section is governed.

On a MAP sensor'd Saab, higher VE results in more flow and a leaner mixture because the ECU does not "see" the extra air going into the engine. This can result in lots of power for the first couple mods. EG exhaust and intercooler will raise the flow (horsepower) and lean the mixture a little. But the next few mods ... say camshafts and a larger turbo ... will cause the engine to run excessively lean as a lot more air is entering the engine than the ECU is aware of.

On a MAF sensor'd Saab, this change in VE only results in lower pumping losses as the ECU controls boost based on a fixed Air-Mass/Combustion value. The hp gain in pumping losses is minimal. The advantage is that T7 can, contrary to popular believe, handle more modifications than T5 without running lean. The idea that T7 cannot handle any is just false ... but that rumor probably came about from the fact that T7 is more fragile. It can handle many modifications ... but cannot handle much abuse; at least not as much abuse as many T5 cars can withstand.

As for software mods alone ... I totally agree with Dr Boost. The only software mods I've seen on the market will do nothing but compromise reliability. The stock T7 ECU is absolutely awesome ... it needs nothing changed without some kind of hardware modification ... which brings me to a better explanation of what hardware modifications accomplish ...

While I might have said earlier that harware modifications on T7 engines don't make much power on their own, they do change the conditions for the operation of the engine. Remember how I said that it's more like a turbine engine? Changing the exhaust, as an example, lowers the EGT, lowering the EGT allows more boost (amongst other things). So the exhaust might not make any power, but it does allow more power.

When Dr. Boost is talking about flow, on a turbocharged engine what he's really referring to is pressure ratio. Because on a turbo engine if we want more flow, we can just increase the boost pressure. Unfortunately that has some negative side effects; it heats things up a great deal. More flow allows the same horsepower, but at a lower pressure ratio, and because the turbo can make that power at a lower pressure ratio, there is less heat, and voila' more power- with no significant compromise in reliability if done correctly. :)

Summary:

T7 won't make much additional power with just flow modifications, or just an ECU change. Turbocharged engines must always be thought of as a complete system, unlike naturally aspirated engines.

Therefore, if you want to make more power, you need your ECU (which governs the turbine section) to work in concert with your upgraded hardware to form a complete system. Doing anything else can potentially cause reliability issues, or just may result in less horsepower than expected.

I hope this is somewhat helpful. I realize some of my oppinions and thoughts are ... unconventional ... and I'm always open to being corrected. Just make sure you have a good argument with some evidence before you correct me, as these are not just my oppinions, but also the oppinions of numerous members of the SAE, along with the oppinions of many turbocharging engineers. (IE Corky Bell, Hugh MacInnes, etc.)

I do love a good argument though. :D Bring on the debate!

Adrian~

Mattlach
27th September 2004, 01:56 PM
While I might have said earlier that harware modifications on T7 engines don't make much power on their own, they do change the conditions for the operation of the engine. Remember how I said that it's more like a turbine engine? Changing the exhaust, as an example, lowers the EGT, lowering the EGT allows more boost (amongst other things). So the exhaust might not make any power, but it does allow more power.

Since you seem to know what you are talking about...

Do you believe the commonly available aftermarket cat back exhausts, and air filter replacements have a significant enough impact to lower the EGT enough such that upgraded T7 software can make a real improvement?

Adrian W
27th September 2004, 02:51 PM
It depends on how restrictive the factory setup is. The only T7 car I have experience with is my MY2002 Viggen.

As far as cat-backs. The Viggen has a very free flowing cat-back exhaust system, but many other Saabs don't. The downpipe is generally more restrictive.

Panel filters are usually a waste of money. The "cobra" intake pipe might make some difference, but it's not a bottleneck or anything. All of the air must pass through a hole less than 2" in diameter as it enters the turbo anyway. The stock tube, while somewhat on the small size, funnels very smoothly into the turbo. Any larger pipe will only create a small difference in operating pressure-ratio as I can't imagine the Cobra tube causing more than maybe 1 psi of vacuum restriction.

If anyone has some concrete dyno or pressure data from measurements taken back to back with an upgraded tube I'm open minded to being proven wrong. But so far most of what I've heard regarding intakes is primarily butt-dyno evidence. They do look dang nice though, and there's nothing wrong with buying one. :)

Here's something interesting to consider about exhausts:

Turbocharger exhaust sides operate at a pressure ratio. For the sake of argument, let's say your Saab's turbine operates at a pressure ratio of 3:1 on the exhaust side.

Then let's say your stock exhaust system contriutes 6 psi of backpressure. (Pretty typical for a double catalyst, double muffler exhaust.)

That means that the absolute pressure on the exhaust low-pressure side is roughly 20.7 psi-absolute. At a 3:1 Pressure ratio your high-pressure side is now at 62.1 psi-absolute! That's 47.4 psi over ambient pressure!

That means your 6 psi of backpressure after the turbo turned into 47.4 psi of backpressure at the engine!

Now say you buy your trick 3" (2.5" will produce good numbers even at 350 hp, but 3" for argument sake) exhaust system ...

This new exhaust only creates 2 psi of backpressure (a 4 psi drop, and 16.7 psi-absolute). Now at the same 3:1 pressure ratio your engine will see 50.1 psi absolute, or 35.4 psi of backpressure.

So your relatively small 4 psi drop in backpressure caused a 12 psi drop in backpressure at the engine's exhaust ports. You can imagine that this helps to lower EGT and increase flow a great deal. That's one reason exhausts help turbo cars so much more than naturally aspirated. :D

You might also feel frustrated by the idea of having 35.4 psi of backpressure, but remember, a 3:1 exhaust PR is typical for about 15 psi of intake boost. So while you have 35.4 psi of backpressure in the exhaust, you also have 15 psi of boost pressure on the intake. That makes the engine "feel" like it has more like 20.4 psi of backpressure.

Furthermore, a well thought out intake and exhaust manifold setup, with a turbo setup for high-end power can reach overall pressure ratios (ratio between exhaust static-backpressure and intake static pressure) of 1:1 or better. That means there would actually be more boost pressure pushing the piston down on the intake stroke than exhaust back-pressure pushing it down on the exhuast stroke! :o

When such conditions are reached, exhaust scavenging takes on an entirely new meaning, as does Volumetric Efficiency. With a low compression engine, you can not only reach 100% VE, and thus fill all the swept volume, but also go PAST 100% VE and fill all available cyllinder volume on each revolution!

Insane stuff. :D

Adrian~

Mattlach
27th September 2004, 03:03 PM
Insane stuff. :D

Adrian~

Sure sounds pretty insane...

Buit its been so long since I took Thermodynamics as a young eager Mechanical Engineering student that a good bit of that was over my head... :P

I replaced my stock 9-5 Aero exhaust with a Remus 2.5" exhaust with a straightpipe where the front muffler used to be... (and surprisingly enough it is not as loud as a fartcan on a ricer, but it does exhibit that snorkeling sound while easing off the gas in gear...)

I then got a BSR T7 software upgrade and J/R Airfilter...

I plan on dynoing the car at some point (when I finally get out of work before business hours). I'll let you guys know of the results...

Stefano
27th September 2004, 03:39 PM
Good job, Adrian. It's amazing how many "legends" are between car tuning enthusiasts, how many miths are kept into consideration but are not supported by evidences. Sometimes they are true anyway, but sometimes.... not. But one definately needs the numbers, to judge and compare.
Good job posting that stuff and keep it coming. That's good that you take your time to explain those things, many people maybe already know some of that stuff but lack the time, the will and the clearness to share them.

Marky
5th October 2004, 12:11 AM
As far as cat-backs. The Viggen has a very free flowing cat-back exhaust system, but many other Saabs don't.

As far as I know, the viggen uses the same cat back system as the rest of the turbocharged 9-3's, including the diesel. The only difference is the rear silencer, which is only there for the looks.

Marky
5th October 2004, 12:13 AM
As far as cat-backs. The Viggen has a very free flowing cat-back exhaust system, but many other Saabs don't.

As far as I know, the viggen uses the same cat back system as the rest of the turbocharged 9-3's, including the diesel. The only difference is the rear silencer, which is only there for the looks.

Adrian W
5th October 2004, 03:48 AM
There was a fair amount of variation in the rear silencer. The Viggen uses what is essentially a straight through glasspack. I've disconnected the mufflers all together before, and apparently the catalysts and turbo do most of the muffling, as it was still not particularly loud.

Here are some part numbers for rear silencers for 9-3's:

B204E (MY2000): 49 66 867

B205R (MY2000): 49 66 875

B235R (MY1999-2002): 51 22 064

9-5 Aero (MY2000-2002): 53 21 658

There actually appears to be a great deal of variation in the rear silencers. The B235Rs all got the same one, but the other models had lots of variation for just about every engine.

Diesels use a fairly different exhaust downpipe, but with a similar cat-back, with a different muffler from any other 9-3.

The 9-5 Aero looks to have a very restrictive exhaust system compared to the Viggen. Tight exhausts tend to make the engine more octane-sensitive. In places like here in Southern California, a 9-5 Aero may be even more responsive to a better exhaust, or higher octane; especially in warmer weather.

That is one exception to the rule of T7 not liking mods. It likes high octane fuels, and high "mechanical octane", especially so the lower the octane fuel you're stuck with. I've found a lower temperature thermostat seems to make my Viggen quite a bit happier in hot weather. Also, thermal insulation for the intake piping makes a fair difference. An exhaust system will help pull hot exhaust gasses out of the cyllinder, and that may allow more power in warmer weather, but not more power than the engine was designed to make.

It just allows you to make peak-stock power in a wider range of conditions.

Anyway ... just thought that might be useful.

Adrian~

Marky
5th October 2004, 09:12 AM
Here are some part numbers for rear silencers for 9-3's:

B204E (MY2000): 49 66 867

B205R (MY2000): 49 66 875

B235R (MY1999-2002): 51 22 064



You don't have to quote EPC to know that the rear silencers are different. They all have a different exhaust ending tip, thus a different part number. The B205R will have two part numbers depending on the modelyear, not because it is different, but because of the viggen bumpers where the exhaust is placed more to the middle. The same goes for the last 2003 verts.

Adrian W
5th October 2004, 06:36 PM
True, however have you seen the shape of the Viggen's muffler? The exhaust note is different, and the muffler is shaped like a cyllinder, much like the resonator.

Many of the other Saabs have a strange, sort of triangle shaped, rear muffling section.

Here are some diagrams to show what I mean:

9-3 Exhausts:
http://img.photobucket.com/albums/v14/SaabTuner/93Exhaust.jpg

9-5 Exhausts:
http://img.photobucket.com/albums/v14/SaabTuner/95Exhaust.jpg

It looks like the silencer was changed in more ways than just to fit the bumper. I believe the Viggen essentially got the Saab sport exhaust system, but with the resonator. I've yet to hear another stock Saab with the same exhaust note, though there aren't so many around here.

Adrian~

Marky
5th October 2004, 11:51 PM
The Saab sport exhaust was never standard on the viggen. Up to MY01 there was a cat back sport exhaust available for the viggen made by Remus for Saab. This was 2.5"

I know the viggen has a different shaped' rear silencer, but I doubt it has a function other then giving it a sportier sound (as you say yourself). At the time the exhaust gasses have reached the rear silencer, they are cooled down and compressed, so performance wise there is nothing to win.

Adrian W
6th October 2004, 04:00 AM
http://trolltuner.com/viggen/index.htm

There may have been a complete Remus exhaust, or it may have been the stock Viggen exhaust sans resonator. Either way it made no difference in horsepower even with the full 3", so I guess it's a moot point.

Adrian~

Chris 9-5
6th October 2004, 04:28 AM
Hi, im Alex I am new to the forum, I am in the process of getting a Black on Black 9-5 areo 5spd with BBS wheels. I was wondering if there was anything I could do, moderatly expensive and easy, to inprove the 230 hp :cheesy: . Not to say that 230hp is bad in any sense. I just want to see what my options are and if this is feasable.
Alex

Ok guys back to original question then if we may, with perhaps the summary that a less restrictive cat and larger bore exhaust will improve throttle and turbo reponse, which may be more useable than increasing horsepower, which is nice :)

DrBoost
18th October 2004, 03:47 PM
Hej !

Air going in, air going out, without too much pressure loss.
Remember that when you do your modifications and the gate to high power is open !

Back to 9-5 Aero (B235R) feed the TuRbo with air, stock system is a bit restrictive. A bigger intercooler is also on the list, then a "big bore" exhaust system.
This with a new ECM s/w can bring you up to around 270-280 bhp, IF you're not living in a hot climate.
The bottle neck is now the 5 cm2 turbine housing, if a 6 cm2 can be "found" the engine can quite safely deliver 280 bhp.
With some more fuel, (Bosch 3.8 bar FPR #0280 160 616) and a better catalytic converter, close to 300 bhp is with in reach.(telling you the truth, on my Aero, I would'nt go that faar with the stock TuRbo, even with the 6 cm2 turbine.)
However, some companies claims 300 bhp with stock 5 cm2 turbine, this is simply put, too much.


Now it's time for forged pistons if you want to continue....

Conclution, stock Aero h/w doesn't support power levels above 250 bhp, end of story.....

Adrian W
19th October 2004, 06:01 AM
Agreed mostly. I live in a hot climate myself. Stock hp is hard to achieve even with mods on a hot day. :cry:

As another note, on many turbo cars a good set of well designed headers can reduce the backpressure the engine "sees", which would work well with the 06 cm housing. Boost-lag with such a setup could be as low or lower than stock even with the larger housing.

I hate to get into headers though because so many poor sets are made. A GOOD set of headers will cost a great deal.

The benefits are complex, and generally are derived from the difference between "static" and "velocity" pressure, the latter of which drives the turbine and has a directional vector. A well designed set of headers will keep the exhaust pressure in the form of velocity pressure (sharp bends diffuse it into static pressure), and keep the directional vector pointed away from the exhaust ports, thus reducing the backpressure the engine "sees".

Now all I need is the money to buy a nice set of headers for my car. :oops:

Adrian~

DrBoost
19th October 2004, 11:47 AM
Hej !

The traditional MHI TD04HL 6 cm2 turbine is not designed to be feed with "too much pulses", poor wastegate funtion will be the result. However, a nice set of headers that converts pulses to a more constant flow will work.

Adrian W
19th October 2004, 02:31 PM
Hej !

The traditional MHI TD04HL 6 cm2 turbine is not designed to be feed with "too much pulses", poor wastegate funtion will be the result. However, a nice set of headers that converts pulses to a more constant flow will work.

Yes, another downside to headers. They keep the direction of flow so straight that they tend to miss the wastegate all together of not positioned correctly. :( That's part of the reason headers are so difficult to impliment.

Headers are great for upgraded turbos, and the addition of an external wastegate can greatly increase flow. Always worth experimenting with and considering as an upgrade. When done right they are very beneficial!

Wastegates are another tale though. A "proper" wastegate setup should be done such that the divided angle between wastegate and turbo is the same. But this is rarely done. :( Also, ideal wastegates are more like throttle valves than poppet valves, but this is usually only seen on grand prix cars and such because of the high cost of materials needed to make a butterfly or slide valve work at 1800F+ degrees!

I'll definitely be looking into an 06cm housing for the Viggen. I'll also have a data-logger soon so I'll record changes and such!

Shame I don't live near Trollhattan, Dr Boost. We'd have some very interesting conversations I imagine! :)

Adrian~

soca
24th October 2004, 10:38 AM
Having been driving the wifes 9-3 for the last couple of months, I am well impressed as to make a Saab my next car of choice. I have followed the arguments avidly on the performanc e upgrades possible and have just returned from test driving a 2000 9-5 Aero auto. The car has 4 gears.

It seems you can get more performance from upgrading the manual cars rather than the auto. My questions are

1. If you upgrade the the auto car to 260BHP which is I believe the max you can get with a stage 3, will the car cruise comfortably on the motorway/highway with the 4 auto gears?

2. Will the performance gains (about 20BHP) on the manual make it much faster than the auto car with the 260 BHP

3. Seems like the BSR kits are the supplier to go with; can someone point me to their website and/or a distributor here in South-east London

4. With the increase in power and looking for good handling, I guess a suspension kit would be advisable. I am looking for handling that willl be comfortable on inner city and motorway drives but at the same time be able to handle the long flowing motorway curves as well as sharp bends on A & B roads.


Apologies if some of these questins have already been answered in other posts

Soca

Chris 9-5
24th October 2004, 12:40 PM
1. If you upgrade the the auto car to 260BHP which is I believe the max you can get with a stage 3, will the car cruise comfortably on the motorway/highway with the 4 auto gears?

I'm confused about your figures here for an Aero, but the auto's work very well with the upgrades mine has a Stage 4 BSR on a 2.0 auto, car cruises, and indeed flies nicely! Boost is limited in the low gears to protect the auto-box

Check out the upgrades for a 2000 Aero here http://www.partsforsaabs.com/default.php?cPath=28_270_292_367 Stage 3 is 289 bhp!


2. Will the performance gains (about 20BHP) on the manual make it much faster than the auto car with the 260 BHP

Thats got to depend upon the driver and the gear change, I guess the Stage 3 manual's maybe quicker off the mark, provided the wheels stop spinning!



3. Seems like the BSR kits are the supplier to go with; can someone point me to their website and/or a distributor here in South-east London

Yep www.partsforsaabs.com



4. With the increase in power and looking for good handling, I guess a suspension kit would be advisable. I am looking for handling that willl be comfortable on inner city and motorway drives but at the same time be able to handle the long flowing motorway curves as well as sharp bends on A & B roads.

There are some great kits available, the koni kit is well rated, as are the eibach kits, I'd recommend the fast Road pads from Pagid too! All of which are available at www.partsforsaabs.com

Oh and welcome to Saab Central Soca 8)