Magical random power increase

[smitty]

Turned off my AC today for the first time in like EVER.

Gave it a squirt and nearly ended up in the back seat! F*** Me! Was like someone cranked the boost two-fold!

I know AC compressors rob power but not that much, surely? Not only did it perform significantly better, but it seemed to emanate about a third less heat from the engine bay. Anyone else experience these massive gains from switching off their AC? Maybe i've got some underlying issue somewhere?

 

[montgomery]

nah a/c is a Thief!

My s14a Struggles with A/c on.

Ie , put you foot in 1 position on the accelerator , put a/c on and feel the struggle.

My first car , when i did the Dohc turbo engine swap , i ripped out the a/c , and since then Have rarly used it.

I just got used to having no a/c hehehe

 

[smitty]

didn't think it was THAT big a thief?!

 

[montgomery]

Not so much when i had the Leg , but other cars i have owned struggled from it.

 

[jet150]

Can't say mine does the same.

My car runs pretty good with the A/C on, can hardly notice the difference.
Is it possible that your A/C compressor needs the bearings changed?

 

[smitty]

How would I determine whether or not they're shagged, apart from the usual take-the-belt-off-and-check-for-play technique?

 

[Scottie]

Yeh, mine runs fine with the A/C on. If the outside temps weren't so high that they needed the A/C, i would think it runs just as good.

 

[montgomery]

Yeh, mine runs fine with the A/C on. If the outside temps weren't so high that they needed the A/C, i would think it runs just as good.

Yeah , Pre explosion , you car did run wicked with a/c.

 

[cyber_scriber]

There shouldn't be the massive difference in performance that you describe.

You tend to notice a performance decrease with a/c on in low powered NA cars and even then, it's not like the car suddenly slams you into the seat when you turn a/c off.

In a reasonably powerful and torquey twin turbo V6 like ours, any performance gain from having a/c off shouldn't be anywhere near as pronounced as what you're experiencing. I certainly don't experience anything like that in my car!

This leads to the question - what's the performance like with the a/c on? Is it appreciably slow and sluggish? Have you had a chance to compare with another VR-4?

 

[smitty]

Not really, the only other two VR4s i've been in were a PFL auto legnum aloooong time ago, and Mooker's modded purple beast, so i can't compare to either, really.
I wouldn't say it was sluggish, but i did expect a little better, but I just wrote it off as additional power loss from the auto transmission.

 

[mills_88]

I hardly ever use the a/c for the same reason. Came from a honda which had the a/c out of a millenium falcon which robbed all available power.

 

[GoldenDragoon]

I think people over rate the power loss or fuel consumption with A/C. On a open road fuel consumption will be practically identical but "VERY" minor loss of power in tall gears (you will need to be very exp with your cars performance to truly pick it). Around town higher idle speed when stopped will pick up fuel consumption a bit but in low gears you won't notice the difference.

If you think differently I believe that either the problem is in your head or your car has a serious issue. I have owned a few cars and driven many more and have hardly noticed the supposed "power loss" of A/C on anything other than up hills on freeways with full cars. It is a load on your motor but generally your motor has plenty of power to spare.

 

[mookers]

My car isn't modded that much, Alex. It just has breathing changes, no extra boost, so I probably got a few killerwasps over stock at most.

I think there might be something wrong if you can really notice the power difference. I've had small 4cyl cars where you could tell, but their motors were making 90kW or less. The three cars I've had with over 120kW haven't really been affected by the A/C.

 

[Guest]

Being a manual makes a heck of a difference to the perception of acceleration. We had to crank my auto's boost up to 15psi to approach the same level of kick that Derek's car has.

But Alex, you might find your boost solenoid isn't working properly or you have a leak somewhere. When I run my car with the EBC totally off it's boosting on wastegate pressure alone and feels not unlike an atmo car to drive. So it spools much slower and loses steam a lot earlier.

 

[mookers]

Being a manual makes a heck of a difference to the perception of acceleration. We had to crank my auto's boost up to 15psi to approach the same level of kick that Derek's car has.

Something to do with shorter gear ratios and my mad clutch pedal skillz*... lol




* smooooooth.**


** Not.

 

[Tom]

When driving the Trueno, if I'm accelerating or sitting still and I whack on the aircon you can reaaaally feel the difference !

Plus the car idles heavier too

I need to replace the knock sensor too though so that already messes with it.. Add aircon, and I'm then running about 20kw total lol

 

[steveP]

arhhh the 'air con off' trick. now u know what its like to have a vtec honda lol.

 

[cyber_scriber]

Yes, Tom, but the Trueno's 1.6 NA is a little down on power and torque compared to the VR-4

Alex, the short answer is that based on the massive power surge that you've described, something isn't right with your car ...

 

[Tom]

Haha yeah I know, was jus sayin' hehe

The VR4 I wouldn't notice much difference with aircon on and off

 

[king_panther]

Well, seeing as the aircon doesn't work in my Super, I couldn't tell you if there's a difference.

Never noticed anything in the Grandpa though, but that's because I rarely ever turned it off I liked it too much