[pmontelo]

This question is for C4C5 or anyone in the know, does the A/C compressor on the LS6 automatically disengage at high RPM to help extend it's lifespan?

I know in my other GM vehicles the compressor does not automatically disengage at high RPM. With the LS6's 6500 RPM red line, I've been shuting off the A/C when doing any serious driving to try and protect the compressor. Is this necessary or are these C5 compressors built stout enough to take the high RPM revs?

Have you had to replace many C5 compressors?

I do like keeping the A/C on especially in stop and go driving because it keeps the fans on and my engine temps usually stay right around the thermostat temperature.

Thanks in advance for the advice.

 

[N4C5S]

All A/C systems since around 79(?) or so have a WOT cut off switch......

As for durability at high RPM, that's one for C4C5....

JC

 

[c4c5specialist]

Yep, jc got it

Hi there,
Well, the WOT cutoff is correct as the PCM controls this function, as well as all other controls to the air conditioning functions.
As for the reliability, I have only done 3 compressors. I am sure that there are problems, however, I have NOT seen alot of them.
Best to you, c4c5

 

[ZO SIC]

I'm not totally sold on the WOT turns the AC off theory. When driving an import and going WOT you can feel the air coming out of the vets get warmer and the engine is no longer bogged down. Now in my '96 Z-28 and my '98 Dually the AC still blows cold even when at WOT for 10-30 seconds... And the '96 Z-28 slows down about .3 and 3mph at the track if I leave the AC on... It just doesn't add up.

 

[c4c5specialist]

Differences abound

HI there,
Well, you might be experiencing design differences between the 2 systems.
As the pressure drops within an a/c system, yo may still have cool air, as the pressures have not equalized. A good way to test this, is to have a vehicle run for 5 mins, with the a/c turned on.
Then, simply shut the car off,and listen for hissing type noises from the engine compartment of the car. You will find that you willl have the noise more in c5, Z28, and pickup. Here is the reason why. Capacity, and obtainable pressures.
You see, imports may not us a high displacement compressor, or a large capacity system. Therefore, the pressure within the system is lost alot quicker, than in c5 or Z28, with over 3 lbs of refrigerant. Also, the compressor, will obtain the correct pressure quicker, once it comes back on.
The program for shutting off the compressor is on every car that Iam aware of, at 4000 rpms and above.
Best to you, c4c5

 

[fcalmes]

Excellent information Paul!! I did not know that. Was sitting here discussing it with Sherylann about the AC not cooling as well at high RPMs and you just explained it. Thanks!!

 

[Bob57]

While at WOT for a few minutes, the air comming out the vents gets warmer. I know my compressor has disengaged.