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For the 900 motor alls I know of is the 24 lb (blue top) ins the 30 lb (red top)
But first let's step back a bit and think why are we wanting to run the 30lb.
Back in the era of the 900 they didn't have a computer to monitor air/fuel mix. The first Windows p.c came out in 1995 and that computer was cave man basic.
The Saab 900t was put together with allot of Saftey devices (knock sencor, fuel cut off switch, over boost protection) all these items now days are voided in your modern car becouse the computer will adjust air/fuel mix to spec. All the 9-5 and 9-3 cars has this computer the only problem with it is a slight hesitation by the computer when you go full throttle.
But back to the 1990's turbo cars, they have a big issue how to get a great boost but still have outstanding gas mileage. So the cars are set up from factory at and optimal performance meaning,
The 2.5 bar and the oem injectors set up never changes the fuel flow regardless of how much air is being pushed into the piston chambers. The fuel will just keep on keeping on, it knows no different. People who mod their motor and turn up the boost psi run into issues with the oem injectors becouse the enormous gain of air being pushed into the motor and no increase in fuel creates what is called a "lean air mix" lean meaning way to much air vs fuel. Depending on how lean the mix is can melt piston rings, burn holes in valves, melt spark plugs,trip the knock sencor every time the vehicle is trying to boost, a lean air mix causes endless problems.
So if one wants more boost they also have to upgrade the fuel to combat the lean air mix problem.
Oem psi on the Saab 900t is 7psi and goes very well with the oem injectors, under heavy boost very slight, or if any lean air mix is happing, remember the turbo is only pushing 7psi.
Now let's say someone wanted to put in the 30lb injectors and is using the stock 7psi boost. Now what's happing is the opposite of "lean" now the motor is just shoveling tons and tons of fuel in the chambers and this is called running to "rich" and would cause the spark plugs to misfire, the cylinder walls would go thru a wash, meaning all the excess fuel is stripping the oil from the cylinder walls causing the piston rings to get excess ware (and would be burning oil before long), and you would notice a huge brown cloud following the car (unburnt fuel) your gas milage will go from 300 miles a tank to 120 and you would have 0 improvement in performance. Running to "rich" will not let the car go into boost becouse once one spark plug misfires the knock sencor will detect it and shut the boost down., but the cylinder wall wash will never stop.
One has to ask themself do you want to build a mod monster or keep the car as a 300 mile a tank runner. i could go on but it's time to look at the back of my eye lids.
posted by 70.193.36...
, Wed, 25 May 2016 11:24:30
, Mon, 23 May 2016 22:43:17
, Tue, 24 May 2016 08:38:08
1, Tue, 24 May 2016 10:51:53
, Wed, 25 May 2016 10:19:33, Tue, 24 May 2016 15:27:20, Tue, 24 May 2016 09:50:092, Tue, 24 May 2016 16:48:211, Wed, 25 May 2016 11:14:5021, Mon, 23 May 2016 18:54:22, Tue, 24 May 2016 09:43:361
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