A/c + Cdv + 6mt

[bmw13]

Is it just me, or does the CDV feel WAY worse with the A/C on? the two must correlate with one another some how, but why is that? thanks in advance.

[Dackelone]

It is just YOU!

They are not connected in any way!!

Maybe you are just feeling the extra HP that the AC compersor is consuming when its on.

[bmw13]

Originally Posted by Dackelone

It is just YOU!

They are not connected in any way!!

Maybe you are just feeling the extra HP that the AC compersor is consuming when its on.

so what i am feeling is just simple power loss due to work else where? makes sense but i was certain there might have been another underlying issue... well what i am describing is the lack of throttle response i guess when the a/c is on. what is the best setting for the a/c to run but not hard, and yet have the engine work efficiently almost as if it were off?

[MastaMind]

Originally Posted by bmw13

so what i am feeling is just simple power loss due to work else where? makes sense but i was certain there might have been another underlying issue... well what i am describing is the lack of throttle response i guess when the a/c is on. what is the best setting for the a/c to run but not hard, and yet have the engine work efficiently almost as if it were off?

It's the power loss due to A/C, and also the reason why I don't use mine. Nothing wrong with your car--my daily driver does it too.

[Itanius]

The A/C affects throttle response even without the CDV delete mod, especially when the engine is cold.

[mad chemist]

Originally Posted by bmw13

Is it just me, or does the CDV feel WAY worse with the A/C on? the two must correlate with one another some how, but why is that? thanks in advance.

bmw13,

I've noticed the same thing with the A/C on. The revs drop a lot quicker between the gears (with CDV delete, this is more pronounced). I suspect the extra drag the A/C puts on the flywheel is responsible for this effect. FYI, I used to own an STi and that was a lot worse with the A/C on.

Mad.

[bmw13]

Originally Posted by mad chemist

bmw13,

I've noticed the same thing with the A/C on. The revs drop a lot quicker between the gears (with CDV delete, this is more pronounced). I suspect the extra drag the A/C puts on the flywheel is responsible for this effect. FYI, I used to own an STi ans that was a lot worse with the A/C on.

Mad.

this is exactly what i was looking for, thanks for the explanation, and help guys BMW FTW

[JHZR2]

Originally Posted by mad chemist

FYI, I used to own an STi ans that was a lot worse with the A/C on.

It is all about the inertia in the system. If the BMW has more rotating mass, between the cylinders, crank and flywheel, it will overcome drop load/step load transients much smoother.

Of course a lighter rotating mass will accelerate faster, so it is all a matter of balance.

[ethermal]

the only time I ever put ac is on is in 6th gear on the highway. If i ever have to down shift first thing I do is turn off the ac. I never ever run ac while running around town.

[Jeef Beef]

Originally Posted by mad chemist

bmw13,

I've noticed the same thing with the A/C on. The revs drop a lot quicker between the gears (with CDV delete, this is more pronounced). I suspect the extra drag the A/C puts on the flywheel is responsible for this effect. FYI, I used to own an STi and that was a lot worse with the A/C on.

Mad.

+1. I get it too - On 40 degree Celsius days over here I HAVE to run with a/c. The revs drop faster and it annoys the hell out of me but it's not too hard to adapt. Sometimes though I forget and I do a crappy shift.

[bmw13]

Originally Posted by Jeef Beef

+1. I get it too - On 40 degree Celsius days over here I HAVE to run with a/c. The revs drop faster and it annoys the hell out of me but it's not too hard to adapt. Sometimes though I forget and I do a crappy shift.

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