Evo 8 and 9 weight reduction thread

[kouzman]

I've been considering working it into my next round of mods. I like the idea of nothing but an alternator to be ran by the motor. Then at WOT, you could pretty much disable everything for very short bursts...
BMW does this on the new M3. Even the alternator voltage gets dropped.

Toyota MR2 has an electric power steering pump...
I think the some of the vettes do to, as well as the BMW as mentioned.

I've just been unsure of what would be required to make it controlled. Unless the power steering pump just moves fluids and the rack controls everything mechanically...

Great thread though. According to the list, my car is down 300 pounds from stock and still looks full interior.

There is this part called Alterpower that people were using in the UK... It would read from a vacuum and when you were WOT it would cut off the alternator thus saving all the power that the alternator steals... Our EVOs if i remember correctly have big alternators, and i dont think we really need them when we are WOT for a few seconds on the 1/4 mile...

http://www.bestservis.com/digerurunl...rpower_eng.htm


This is one of the best threads around and i visit it frequently. It really helps me decide on what it worth to remove from my car for next season without loosing its street driven character:

Last season with 1/2 tank i was racing at 3370 lbs with me in. I weighted 253 lbs so with clothes and helmer probably close to 260. I always weight my car with me in since thats how i race it! LOL
Obviously my car has plenty of weight reduction mods but nothing crazy. Still full interior, ac, ps, radio speakers, full insulation, etc...

For next season i am looking:
- 17 lbs rear crashbeam (the front is already removed)
- 32 lbs Apexi N1 coilovers
- 28 lbs Hoosier QTPs 16" (one hoosiers website they are 18 lbs so thats 7 lbs per tire savings)
- 7.3 front strut brace
- 9.5 lbs rear GT Spec trunk cage
- 7.5 lbs RMR lower underbrace
- Wheels i am considering it a wash since instead of my 17 Koseis i will use the RX7 FD 16" wheels with front spacers
- 5 lbs floor mats

Thats 106.3 lbs with almost everything on the car!
Plus i already lost 30 lbs myself so we are probably looking at 3233 lbs at least... Still a fat pig compared to others but at least i am trying! LOL

[Ticketmaster]

Any of you guys with the dynos feel like testing that alternator thing? I would be very interested in seeing the results.

[Force-Fed Performance]

Steering? EVO steering is awesome, even more awesome and less power robbing when it's electric......but who would do something like that?! (insert evil laugh)

Aww i like your style, i have a couple older cobalt steering columns i may take apart and check to see if there is something that could be done. Their steering racks are tiny as hell also and would save alot of space/weight

[Evo_Kid]

Steering? EVO steering is awesome, even more awesome and less power robbing when it's electric......but who would do something like that?! (insert evil laugh)

I've been considering working it into my next round of mods. I like the idea of nothing but an alternator to be ran by the motor. Then at WOT, you could pretty much disable everything for very short bursts...
BMW does this on the new M3. Even the alternator voltage gets dropped.

Toyota MR2 has an electric power steering pump...
I think the some of the vettes do to, as well as the BMW as mentioned.

I've just been unsure of what would be required to make it controlled. Unless the power steering pump just moves fluids and the rack controls everything mechanically...

Great thread though. According to the list, my car is down 300 pounds from stock and still looks full interior.

Honda's S2000 has a electronic steering rack.

[03whitegsr]

One big issue with dropping output voltage at WOT is still having an electrical system that can keep up.

High powered cars use a LOT of electrical power at WOT. Between large fuel pumps and upgraded ignition systems, they can easily drag down all the current from the alternator as is and then pull battery voltage down under 12V.

Something I'd like to try would be either a dual voltage battery, giving you 16V for fuel pumps and the ignition system and then 12V to everything else. This would also require a 16V alternator, which you can actually get a very compact and light one to replace the decently sized stock alternator.
Dual Voltage Battery
Mini 16V Alternator

Or a 14V battery.
14V Battery

[David Buschur]

Man, good thing I am trying to make these forums superior to all the others The information I have been posting on here is more indepth than I usually get!

First, cutting power to the alternator on an EVO is not a good idea at WOT. You will end up with multiple problems. Yes, the alternator is a drag. The water pump is one of the larger drags on the engine, that is why we've been running electric pumps for many years. The power steering is another large drag and that is why so many cars are going to other forms of power steering. MPG requirements make dropping the components the engine has to run a good choice, more power,more MPG.

The MR2 pump for the EVO is one of the best choices. The AEM EMS (and other ECU's) can be set up to operate the pump with a seperate PWM circuit board. The voltage requirements go through the roof though and you need a very big alternator. The EVO alternator is only 95 amps I think. My car currently has a 180 amp custom built alternator on it........wonder why? The power steering is used mostly at low speeds, at those low speeds the PWM is run faster so the car steers easy and then you can cut this power requirement down or off at higher speeds.

Sheesh, how much is my mouth going to run? When I installed the new alternator on my car everything worked better. Voltage is typically 14 v and even under the heaviest loads it stays over 13 volts.

I see many EVO's that drop into the 11's at WOT, many times though that is a grounding issue, that too can be solved, usually, with just one very heavy gauge wire running from the firewall to the intake or block.

BTW, to upgrade to the really high output alternator and to consider this electric power steering idea the alternator to the battery factory cable has to be upgraded to a much larger wire.

What's that old song? "Oh no I said to much, that's me in the corner......"

[03whitegsr]

The MR2 pump seemed like it was going to be pretty damn heavy, and then the power assisted racks are always heavier then a manual rack. But the ability to make it work with the factory rack is pretty alluring. The idea of an electrically assisted rack over an add on pump has me very interested. Other then the extensive amount of fabrication required, probably to the extent of a new front cross member, I wonder if there is even one out there that has a quick ratio like the stock evo steering.

David, cutting the alternator at WOT might not be so bad with the 16V battery. The idea being that even if the current draw on things like pumps and ignitions is high, the 16V side would still likely keep voltage up in the 14-15V range even with the alternator not producing electricity.

The 12V side would be used to run the rest of the car, where even if power drops into the 11V range, things still work. My biggest reservation though is how would things like ignitors, pumps and injector drivers handle the 16V when the alternator is running.

That little guy alternator is also only 50 AMPs, you'd have to actually get energy conservative on low loads. Things like staged pumps with cut down resistors like the stock system would be needed. It's very heavily involved, and probably not worth the effort on something like a street car. For an all out race car though, without question I'd go to a 16V setup.

[FJF]

I wanted to see where my car was in relation to stock.

Weight savings:

Baer rotors on all 4 corners, RPF1s, Hankook Evos - 40lbs (of rotating mass)
Exhaust - 25lbs net
Spare - 38lbs

Weight added to the car:

FMIC - 11lbs
Trunk cage - 9lbs
Whiteline F/R anti-swaybars - 10lbs net
Audio gear - 70lbs net

Total - 3lbs of saved weight. I'm not unhappy with that. The car feels significantly lighter and more tossable by the virtue of decreased rotational mass, the weight of the larger anti-swaybars is offset, as is the weight of the audio system that provides an almost infinite amount of pleasure.

[Evo_Kid]

I wanted to see where my car was in relation to stock.

Weight savings:

Baer rotors on all 4 corners, RPF1s, Hankook Evos - 40lbs (of rotating mass)
Exhaust - 25lbs net
Spare - 38lbs

Weight added to the car:

FMIC - 11lbs
Trunk cage - 9lbs
Whiteline F/R anti-swaybars - 10lbs net
Audio gear - 70lbs net

Total - 3lbs of saved weight. I'm not unhappy with that. The car feels significantly lighter and more tossable by the virtue of decreased rotational mass, the weight of the larger anti-swaybars is offset, as is the weight of the audio system that provides an almost infinite amount of pleasure.

Get rid of that audio gear, lol.

[mullen]

would removing the strut tower bar all together pose any issues for daily driving...its common to see them removed on all out drag cars but not on dd cars.

[FJF]

Get rid of that audio gear, lol.

I love music. The system does a lot for my enjoyment of the car. This said, it can lose almost 40lbs, if I replace 3 of my Zapco amps with the newly released Zed 6ch. I might do that just because, but I'm not sure how much of a difference it would make dynamically. I installed the amps at the very rear of the car and at its lowest point, so the weight has a fairly low center of gravity.

[03whitegsr]

David, have you looked into electrically assisted racks? No fluid to worry about, probably more compact too, but might be difficult to package for the Evo.

There are several OEM versions available.

Citroen
Acura NSX
Smart Car
Hyundia Atoz
Chevy Cobalt
Mazda 3

[yellowevo42]

Dave daily drives with no front strut tower bar if i am correct..

[David Buschur]

I have not looked into electric assisted racks, I just have the "complete" set up here I put together using the MR2 pump.

I do not use a front bar on my car.

[03whitegsr]

Cool, when you say MR2 pump, are you talking about the '90-'95 turbo MR2 or the'00-'05 Spyder?

Both have electric pumps. The Spyder has a pump with built in controller and resevior.

[tsitalontnr]

If the additional strain on the alternator causes more drag with an electric motor, how much better is it than the stock power steering

[03whitegsr]

You shut it off in a drag race situation.

In a road race or auto-x situation, it runs independent of engine speed and should make it more predictable. Also, if you get tricky, you can run it off car speed and steering angle. It basically shuts off when going straight and at higher speeds.

[Appauldd]

A couple more little panels that are not needed are the one under the steering column 1# and the one behind the knee panel 1.5#.

[evodan2008]

is the 180 amp alt available to the public Dave?

[Rogue]

Just looking at all these light weight options...


I have an SSL.. the Pig of the evo world. Im ok with that. =)