do you free that much power when you remove the power steeting, smog pump, and air conditioning off an FD? I know its a trick used by many V8 guys and I figure the concept is the same.. But is the difference worth it? can you gain what 5-10hp doing so?

 

You will not gain a lot of horsepower, but you will benefit from the weight savings.

 

about how much weight will be saved by ditching those three items?

 

Unlikely it would make any noticeable difference.

Jimlab weighed all of that stuff and posted weights in a thread in the Archives. I think its also linked in the FAQ.

 

maybe a little more throttle response since you dont have all those pulleys straining the system.

 

Underdriving the water pump will create less cavitation at higher rpms and thus better cooling. 'Performance benefits' from underdriving other components are pretty debatable, but do a good job of selling the kits.

 

I seriously doubt you would notice the difference. The airpump is not engaged under full throttle (or over a certain RPM, I forget...), I think the AC compressor does the same. (someone correct me if I am wrong)

Cleaning up the engine bay and removing some weight are other benefits.

 

you do feel a noticeably difference when you remove air/smog pump and install new pullies and belt such as Greddy or Unorthodox. the car pulls harder, and better air flow in the engine bay to help the turbos run a bit cooler

 

All I noticed was that my Throtle Response felt quicker...and and empty looking engine bay...lol..

 

I would be surprised if you even felt the horsepower gain. There are much better ways to go about it than deleting creature comforts. Like said above, the airpump and ac compressor both disengage a high rpm. How much power does it really take to spin a free-wheeling pulley? Plus I can't help laughing when I see some guys try to parallel park their cars with no power steering

 

Smog pump if off at 3000rpm (2500rpm with the PFC) and the AC is off under WOT. Weight difference is minimal and selling a car without AC or PS is going to be much harder. Depending on where you live, removing the smog pump will also make selling harder.

A clean engine bay is purely an aesthetic choice; I find it easier to just shut the hood.

 

I never noticed a change with or w/o the air pump fwiw.

 

interesting guys.. yeah i think cleaning up the engine bay will be nice.. i can then prop change spark plugs with a blind fold on! ha ha jk

also since more mass is removed wouldnt that help out with cooling also since there is less restriction in the engine bay and less heat soak? just a thought.

 

...but only at sustained higher rpm, such as you would only encounter while tracking the car. The instant your rpms drop to normal driving levels (as in, say, less than 6000 rpm), there's little to no cavitation with the stock diameter; using an underdrive pulley on a car that sees street use drops your cooling system's efficiency.

There's plenty of other components surrounding the turbos that do a far better job of blocking engine bay airflow than the airpump.

+1. My FD doesn't get entered in many concours events...

It's the engine block and turbos that create the vast majority of heat, not the airpump and P/S pump.