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hunterD
09-09-2006, 01:53 AM
OK another thread i've searched for but dosnt exist so I'll start one.

1. How much power is lost when VTECing whilst the air con is on?
2. VTECing whilst the air con is on. good? bad? or dosnt really matter?
yourfather
09-09-2006, 02:06 AM
wtf dilligaf
CUL8R
09-09-2006, 06:04 AM
OK another thread i've searched for but dosnt exist so I'll start one.

1. How much power is lost when VTECing whilst the air con is on?
2. VTECing whilst the air con is on. good? bad? or dosnt really matter?
im pretty sure the factory ecu is set to disable vtec when in high cam.
iamhappy46
09-09-2006, 05:37 PM
1) A/C is a constant drain on the engine, so you loose the same amount of crank energy regardless of VTEC being on or off.

2) It does not really matter

I doubt it would turn the A/C off when VTEC is on BUT I do believe that the EK4 VTiR temporarily removes the load from the alternator at full throttle(correct me if I am wrong ECU-MAN?) for more crankshaft power.
CRXer
09-09-2006, 07:55 PM
Bigger drain on engine when compressor clutch engaged,ie A/C on.

i know my aftermarket upgrade to the stock ecu lets u disable A/C after a preset rpm is reached and/or a preset throttle position is reached,dont know whether this is a function of the stock program or not.

BTW,load from alternator?????? Its a generator not a consumer & has a constant negligble load on the engine apart from the belt & bearings.
CUL8R
10-09-2006, 08:51 AM
yeah some ecus will have a/c shutoff conditions but yeah im pretty sure the preludes got a/c shutoff when in vtec standard.
revNhevN
10-09-2006, 09:46 AM
I know hondata can turn off the A/C when set conditions are met. I think it can be throttle position or revs.
CUL8R
10-09-2006, 11:48 AM
yep ur right,
u have two settings on hondata, given throttle position or rpm
http://i14.photobucket.com/albums/a309/CUL8R/acshutoff.gif
Zilli
10-09-2006, 01:34 PM
isnt AC disengage upon WOT applications?
Limbo
11-09-2006, 06:10 PM
yes all correct a/c is disengaged on high loads. Honda did a good thing ;)

ALso vtec still works with a/c on.
Mst_Mugen
11-09-2006, 07:31 PM
ive noticed that vtec doesnt kick in as hard when air con is on though.. mayb its just my car :( ... majority of the time i drive with aircon off
hunterD
11-09-2006, 09:30 PM
I don't think my car goes as hard when my ac is on. i praaah'd and was wondering how come it dosnt feel as fast, then noticed i had my a/c on. feels like a slug, even when accelerating.
Limbo
11-09-2006, 11:32 PM
yeah it disengages the compressor from making cold air but it still has the unit on so it still zaps abit. Anyway due to cost of fuel shouldn't use the a/c too much