Does anybody know if the “gear changing” light is at red limit or is it at revs (plus gear changing delay) that gives the best torque to the drive shafts for the next gear compared to previous?
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Does anybody know if the “gear changing” light is at red limit or is it at revs (plus gear changing delay) that gives the best torque to the drive shafts for the next gear compared to previous?
the red light is not at limiter but some hundrets rpms before limiter.
So, it doesn’t have anything to do with the optimum torque from wheels?
explain please,torque is from engine.Quote:
Originally Posted by OldF
Oldf means the red light flashes at the point when max torque is measured at the wheels in relation to engine rpm.
For example if peak torque is reached at 5200 rpm and rev limit is 7500, does the shift light flash at 5200, 5500, 7000, or 7500 rpm?
If I am understanding correctly...
Thanks Typath107,
It’s sometimes difficult to explain technical things in English when it’s not your native language. :confused:
That’s what I tried to explain. Engine torque is of course always the same on same revs but the revs on which the max torque is on the wheels, depends of the ratio of the gearbox / final ratio.
Current gear ratio divided by next gear ratio times peak engine torque revs (For example 2nd gear ratio / 3rd gear ratio * engine peak torque revs).
What You need is to use biggest possible power all the time through the gear. Torque is a value which is good for understanding the engine characteristics but it's often wrongly interpreted because it changes through gear ratios as You said. Power keeps same through gears (except some looses of course). Basically if You have any of the two curves You don't need the other. It's much simpler to understand the engine from power curve in my opinion because peak power is always the best You can get while peak torque not.
You shall shift the way You have always the biggest possible area under the power curve through rpm range You use. For example You have an engine which has peak torque at 4000 rpm but peak power at 8000 rpm. For best performance You shall stay around the 8000. Where You would shift up depends on the shape of power curve but it will be somewhat after peak power.
That’s correct. The torque at the drive shafts is highest (with the correct gear) when the power from the engine is around peak power.Quote:
Originally Posted by Mirek
I made few years back some calculations to see how it looks on a graph. The Mitsu example is not the best one because the peak torque is little below 3300 rpm and peak power is already at 3600 rpm. The Subaru has the peak torque at 3500 rpm and peak power at 4400 rpm.
Mitsu
http://i267.photobucket.com/albums/i...ps746b0df7.jpg
Subaru
http://i267.photobucket.com/albums/i...ps5b522695.jpg
With a little googling I found three different ALS systems.Quote:
Originally Posted by Mirek
- Air bypassing the throttle body to the intake manifold. Fuel from the fuel injectors and retarded ignition. [/*:m:2mmy6vq0]
- Air directly to the exhaust manifold. Fuel from the fuel injectors and retarded ignition. [/*:m:2mmy6vq0]
- Both air and fuel directly to the exhaust manifold and retarded ignition. [/*:m:2mmy6vq0]
I assume that it is the last one used by WRC cars (and the loudest one), or is it?
I wrote that post bad, sorry. It shall be that with R5 all the air must go through combustion chamber (and if I understand right it must go through throttle as well) not directly to the exhaust. The fuel as well must be supplied from engine fuel injectors. I don't know if WRC cars have fuel injection into exhaust but sure they have air supply line to the exhaust.
I'm no expert in this...