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Discussion Starter · #1 ·
I want to check a couple of things with experienced turbo users.

In my handbook 230bhp aero, it says that 98 ron is recommended and if 95 ron is used then loss of power can occur in ambient temps of plus 25c.
Is it ok to use 95 ron in cooler ambient temps or do you still get power loss but too subtle to detect ?

Is there a historic problem with the oil breather apparatus that i should investigate ?

Anything else to check that comes to mind to ensure i have max turbo power ?

Thanks
 

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Originally posted by metaxu:
[qb]Is it ok to use 95 ron in cooler ambient temps or do you still get power loss but too subtle to detect ?[/qb][/b]
My 9-5 has been upgraded to your power level and 95 ron Sainsbury's unleaded works fine for me

Originally posted by metaxu:
[qb]Is there a historic problem with the oil breather apparatus that i should investigate ?[/qb][/b]
Yes the 9-5's and 9-3's have had several PCV updates on the oil breather system, you should make sure these have been done, try a search on the 9-5 forum for some recent threads like this one here!

Originally posted by metaxu:
[qb]Anything else to check that comes to mind to ensure i have max turbo power ? [/qb][/b]
The standard Bosch dump valve is prone to failure,the alloy ones from Forge etc are more reliable and serviceable

Good quality (Mobil One or similar) fresh oil is the life blood of your turbo too


You can also do an adaptation run as the ECU adapts to the way the car is driven. Pull fuse 17 for say 30 mins, to reset ECU, then replace and drive like a hooligan around your private race track, there is a more technical process but the effect is the same


Hope that helps, Chris
 

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FYI, pulling a fuse or disconnecting power, however done to the ECU, will not help in the adaptation process. Provided that there is a minimum of 3 to 5 seconds at WOT in 3rd gear or up, the ECU will adapt to max power possible. I was also told by a certain Saab engineer that pulling the fuse will also ruin any good, long term adapting the ECU has done. It is better to simply do the adaptation run.
 

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Metaxu, I also have a 9-5 Aero and I wondered about the fuel. I tried 95 and then BP super, 95 and then BP super again. I couldn't tell the difference, so I stuck with 95, however, I always felt like the car didn't have as much
as it should have had. The dealer investigated a couple of times, put new plugs in and said it was fine. I wasn't convinced.

I happened to fill it with optimax and also gave it some welly - BRILLIANT I think this was what it had been missing, this was in February so no 25+ temperatures either. Shortly after I had it rolling roaded and it gave a best figure of 247bhp (and it is a 230spec).

Optimax worked for me - might be worth a try??
 

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Metaxu,
Your car will run fine on 95ron but I think you'll find that once you've tried Optimax you won't want to return to the 'ordinary' stuff.
Optimax everytime for me.
Better mpg, smoother acceleration.
Stay away from the 97ron Esso super unleaded. I did notice a very minor increase in mpg but not one that was worth the extra pennies. For some peculiar reason the Esso 97ron is more expensive than the Shell 98ron (well it is round my end anyway)

Agree with Chris B on the oil front;
Good quality (Mobil One or similar) fresh oil is the life blood of your turbo too    [/b]
If you're oil hasn't been changed in the last 6 or 7 thousand miles then get it drained off ASAP.
You will notice the difference.
Lots of threads in this forum on oil changes.
 

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You could face issues with det on lower octance fuels - an issue I've never really seen addressed on here yet even with remapped cars. You can run 95 ron with an octacne booster or use Optimax - look on Scoobynet as there are a number of threads relating the mertis of otimax vs 95 ron vs BP ultimate and effects on performance etc.
 

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The reason detonation is not usually mentioned here is that Saab's APC function compensates for lower octane fuel (down to 95 RON anyway) at the expense of power output. Even modified cars do this as long as you don't override APC by winding up base boost or fitting a manual boost controller. Or unless you run very close to the limit of the fuel system. Reports of excessive detonation have referred to Saabs that have been run at high altitude and octane rating rather less than the the 95 RON equivalent. These reports seem to be confined to the US market.

I haven't seen any evidence to suggest that running a Saab engine on the minimum octane rating recommended by Saab will cause any damage.

If there's such evidence on Scoobynet, though, I'd appreciate a link as it would be very interesting.
 

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Discussion Starter · #8 ·
Hi, thanks for replys, I have been running on 95, and to be fair, the engine has ran superb, feels very good - But even though im tight for money, anything that may add extra boost and claims to clean the inj system is worth a try so i will fill up with the shell optimax on next tankup.
I am also going to immediately order that oil vent kit.
Pardon my ignorance but what r the symptoms of the dump valve starting to fail or is it better just to replace it as my engine has 57k on it ?
 

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the dump valve on my 9000 T lasted 17years.. so i then bought a 2nd hand one off a 9-5 aero.
mine was stalling or dipping revs on throttle close (under boost), vac leak, and low boost.

i don't think yours will have a problem yet....
 

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All the adaptaion does is teach the car your driving style so it drives like you want it to. Most people adapt by pulling a fuse (WHICH ONE?????) to lose the memory of the current state. Then you drive it on full acceleration, preferably up hill, in top gear. Do this a few times and the car realises that you are an animal and will perform quite briskly for a while.

Trouble is that as soon as you start driving "normally" it will refine its learning as you go and back off its throttle response etc and adapt to the "new" style. It does this all the time.

So if you've been driving like you want to for some time and it suits you, you need to do nothing. If you just drive hard for a bit it will add that experience to its memory. Eventually if you drive hard all the time the car will match you. Adaptation just removes the cars memory so it only has the recent info to go on.
 

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Turbo Talker
You just cleared a lot of fog from my desert eyes. I live at the coast and with the atmospheric pressure suited to turbo-engines, the performance and the responses is on par with the reasons I joined the marque in the first place. Nicked a K & N airfilter and oil filter 3 months back (from a supplier in the USA) and must admit the surge is relentless! What are the gains?

Many thanks!
 
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