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No big deal, but HTH means hope this helps... :)
I painted the calipers with Rustoleum Sunset Red (I think). It has held up extremely well, but you have to be a little careful if you use a power washer to blast off the brake dust. If you are aiming at the caliper and get too close, the paint will come off. I did this on one by accident and had to touch it up. Other than that they still look great! Been painted for 7 months or so. New brake packages are available, but the stock ones are actually really good so I see no real need at this time.
I met my dyno guy after I had already installed the Abbott muffler, so I don't have documented pre and post mod power. They claim 6-8 hp, and I think that is entirely possible. The new muffler is lighter, looks better, and the car sounds great. After I chopped off the old muffler, I had to drive it around unmuffled just for kicks and to get an idea how much the stock muffler lowered sound and restricted power. Fun drive!! Under boost, the car sounded like a giant blow dryer - I was grinning the whole time. I had to put the car away before I got into trouble. The muffler install was kind of a PITA. Getting the old one off requires you to cut the exhaust pipe and I didn't have the right tools with me, so it took forever. Then, when I went to put the adapter on, it was the same size as the exhaust pipe when it was supposed to fit inside it. Luckily, I did have my tailpipe expander, so I widen the stock exhaust pipe enough to get things to fit. The adapter is nice because it lets you center the new muffler in the opening perfectly - looks great and no melted body work. I bought the muffler slightly used, so I got a great deal on it. But you have to keep in mind, it is not an "exhaust system", it is just a muffler - commonly called an "axle-back" kit (as opposed to a cat-back or downpipe and full exhaust.) There is another muffler, called the center silencer, which is still in my car and all the piping is stock (2 1/4", if I remember correctly).
On the dyno graph, both horsepower and torque are shown on the same graph - there is a color-coded legend to the right of the chart telling you which is which. These measurements were made at the wheels, whereas the factory publishes the numbers at the crankshaft. After drivetrain losses, which look to be 15-20%, I am getting 182 hp and over 200 ft-lbs to the ground.
I know ECMs that adapt driving habits are common on cars with automatic transmissions. The modify shift algorithms to meet your driving habits. Cars with manual transmissions would not do this, as all they learn are short and long term fuel trims to get a perfectly burned air/fuel mixture for emissons, just as the automatics do.
The SAABs with T7 and T8 (ours) engine control systems primarily control engine torque with airflow, not boost. So max boost is a relative term. Around town in the lower gears (at sea level, 32 deg F), peak boost is around 10.5 psi, maybe 11 if it spikes a little during a shift. But on the highway the other day, I hit 12.5 (sea level, 42 deg F). It is temperature, altitude, and airflow dependant. Let see if I can explain this without getting too techinical...
Mass air flow, when combined with the proper amount of fuel, is directly proportional to engine torque. Mass air flow is the mass of air entering the engine with respect to time - often written as grams/sec. It is affected by volume and the density of the air. Cold air is more dense than warm air, and air at higher altitude is less dense than air at sea level. Higher boost pressure increases air density and volume of air increases with engine rpm (flow). For a given volume of air, the more dense the air, the larger the air mass and potential for engine torque (if that air mass is fully combusted). The T8 ECM looks at accelerator position to acquire requested torque and looks at multiple sensors to determine how to achieve that value. It will first open the throttle angle to increase mass air flow and if that is not enough to achieve desired torque, the turbo wastegate is closed to allow boost. Fuel required to make the air mass burn stoich (14.7 parts air to fuel) is injected. During closed loop, the O2 sensor checks the exhaust for unburned fuel content and adjusts the fuel mixture to meet 14.7. During open loop, the ECM refers to tables to calculate the proper fuel. If calculated fuel levels (in open and closed loop) have to be changed to make the desired O2 sensor readings, short and long term fuel trim values will offset the tables so the calculations are correct. So much for not getting technical.
I wonder if anyone is reading this... :)
Say you have two identical engines with T8. The only difference is air entering engine A is colder than the air entering engine B. To achieve the same torque, engine B will require more mass air flow. This can be achieved with a greater throttle angle, but say both are already at wide open throttle (WOT). Then engine A can produce more torque at a given boost level than can engine B. But if you look at this the same way T8 does, engine A does not need as much boost as engine B.
Now say you have two T8 engines, both at 3500 rpm, WOT, and in the same environment. Engine C is in a car which is in 6th gear while engine D is in a car in 2nd gear. Engine D will be able to achieve a desired torque with less boost pressure than engine C because engine rpm (and air volume) is now tied to vehicle speed and the final gearing after the gearbox (torque multiplication). Other than boost spikes during shifts, you will get your highest boost pressure on the highway with T8. Max boost pressure (not including spikes) is variable up to a point ~12.5 psi, but you may only see that in lower gears if it is hot out or you are driving through the mountains.
Clear as mud?
Niteman
'03 Vector 6spd
posted by 68.62.3...
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