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Anyone know where, or how, I can hook up a system to keep the vehicle at high idle when sitting parked? I find that with my high current draw, the car being parked, and it getting colder out, the lights dim, and my strobe packs mis-fire due to low voltage after about 15 minutes of sitting on the side of the road.


Reccomendations? and no, removing crap not an option :moon:

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After looking at your website and reviewing your additional equipment as listed perhpas you can go by your local airport and swipe one of their auxillary power units. Hey, you have a hitch on "Flash", why not! :-)


Warning Equipment

Whelen 4 strobe Mini-Edge Bar with rear halogen flashers

Whelen 90 Watt Strobe Power Supply

Front Hideaway Strobes in Corner Lights

Front Par 36 Grill Strobes

Wig-Wag Halogen lamps in headlights

Whelen Dual Halogen Dashmiser in rear window

Whelen Air horn/PA Unit with 100 Watt Speaker

Touchtronics 6 switch membrane control panel



Icom FT-2720 Dual band VHF-UHF Transceiver

Maxrad Dual band VHF-UHF Antenna

Motorola HT-1000 MTVA Unit with 25w amp

Antenna Specialists UHF antenna

Relm MS 2000 Mobile Scanner and antenna

Nokia CARK 133 Hands Free Unit


Driving Accessories

60 watt Halogen Driving Lights

150watt Halogen Driving Lights

Whistler 3300 Remote Mount Radar/Laser/Safety Alert Detector

Alpine 4x40watt CD FM Radio

Priority Start Pro Series Battery Protector

On Board Automatic Battery Charger

150amp Aftermarket Alternator

Remote Starter/Light Control

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Actually, think you would need an "over" drive pulley on the alt. I've never heard of one, not sure if you'd need to worry about the alternator spinning too much when the engine is at high rpms..

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I believe there are systems sold for Jeeps that increase idle for welding and winching.

You could check a Jeep website or a 4WD mag.

We used to use a hand throttle cabe for the same thing when I was a kid.

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The automatics have a system to increase idle don't they?

And it would seem that the AC system would have a switch that would increase idle a bit when AC is on. The AC one would probably only give you a couple of hundred RPM increase, but that might help if you ran a switch and a wire to that.

All an idle control is is a solenoid and a switch.

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Sounds like you just have way too much electrical equipment for the electrical system.


What battery do you have, is the alternator stock? Has it ever been replaced?


I wouldn't recommend messing with idle stuff like that. Unless this is for when you're doing work outside the vehicle and need the lights....and if that's the case, just stick a small something between the throttle stop screw throttle linkage.


Really, you should have an optima yellow top if you don't.....and possibly two for all that stuff. Also, your alternator probably could used to be replaced if it's still original. There's really not much an option for HO alternators that bolt in easily. I have one that a guy in Dallas sells. It's meant for the newer subarus. To fit it on mine I had to extend the main power leads and re-wire the other leads to a new plug.


As for the underdriving option. It is an option, and I'm doing it. You want to underdrive the alternator pulley. The alternator pulley is a driven pulley, not a driving pulley. Think of a bicycle....when you put the bike in the smaller gear in the back.....you go faster.....decreasing the size of the alternator pulley does exactly the same thing.


Go Fast Bits out of Australia are the only company I was able to find that makes an underdriven alternator pulley. I wanted just the alternator pulley and not anything else, since I'm going to be going back to stock sized aluminum crank pulley. To do that I contacted GFB directly and they were able to help me purchase just the alternator pulley through autospeed. I'm still waiting on the pulley since the anodized red pullies were out of stock.


With the GFB underdriven alternator pulley, you'll get an increase in rpm of roughly 100 rpm....that's it.

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The Battery is Just a plain old battery, considering replacing it with a yellow top, however still concerned about using a deep cycle for cold weather cranking.


Would that do the trick? Should I think about getting the alternator replaced?


The draw for the system when it is on draws 26.8amps, give or take a few. That is with all the lights running, the siren on, radios transmitting, and flashers flashing.

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draw that much. do you have a hip stereo place near you? some of those guys have serious alternators on Japanese cars.

I liked the idea of the overdriven alternator pulley.

It does seem that you could prettey easily make something to increase the idle.

Years ago I saw cop cars in Augusta Maine that were subies. They must have solved the problem then.

Somebody must still use subies for police work.

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That amperage isn't too bad....


How many miles are on the car? Is the alternator original?


I'd highly recommend you replace the battery with a yellow top. When I was going to school in PA, I killed my battery.....got a normal battery.....it worked....however stereo never sounded as good, and I had light dimming or other weird issues.....killed that battery in a year......said screw it, bought the yellow top, and was quite amazed at how everything just seemed to 'brighten up'


The optima yellow top is a starting/deep cylce battery. It is not a normal deep cylce and will be more then enough to start your car. Like I said, I lived in PA for 4 years while going to college and even during the coldest winters the optima started the car fine. The only time I'd say the car started slowly was when I leave the car sit for 2-4 weeks and then started it up...this was during winter. The car still started fine, just slower then it normally did....no biggy....


Go with the battery first....If you have high miles, it probably wouldn't be a bad idea to get a remaned alternator as well. Both of those things should help you out a lot.

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Just hit 121000 the other day, I will look into that Optima Yellow top, is there one that fits in the same space as the stock? I notice that there technically is no "reccommended" battery from the optima site, nor anyone else. I will buy the battery from a store anyway.


Reccomendations? Thanks guys you are really a wealth of info, just wish I was more useful once in a while! :banana:

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Think I got a little confused in my reply. A smaller alt. pulley will produce more alternator spin (more current) at lower rpm's, but this is called an overdrive pulley. An underdrive pulley is larger in diameter and will slow down the rotation of the alt. freeing up power for the wheels.


27 amps doesn't sound like too much, where are you measuring from the alt to the batt? Your site mentions a 150 amp alternator, I would think that would be quite a bit. Is your wiring beefed up enough? You'd need some pretty heavy gauge stuff to the batt. and then maybe some fairly heavy gauge stuff to some distribution points for the more power hungry accesories.


Better batt is not a bad idea either.

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I think the optima battery is a good idea.


I would also think about a high idle solenoid like the old carbureted cars had. Put a switch on the dash and interlock it with park or neutral. Rig it up so it presses on the throttle.

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150amp alt bit the can about a year ago now, need to update that part of the site, I have the stock one back in there now, think it's suppossed to put out 60amps, however I am not sure, nor have I measured how much it's really putting out.


As far as how I measured the amount of amperage, I used an ammeter, (measures the amount of electrical current flowing through a given circut, given in amps).


I am running 4ga marine cable from the battery to a MAXI fuse block (30amp fast blow fuse) and then it goes from that block to two (2) 10ga wires feeding a fuse panel which powers the accessories.

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There's no real application for the legacy. The only issue you'll run into is that the optima sits a little lower then the normal one......it's a little wider, and the positive lead for the battery may need to be stretched slightly......

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It's a HO alternator built by a place in dallas. I got it from ruiner on Nasioc. max output is 160 amps


I don't recall exact amount....I keep forgetting if it was 300 or 400......think 300.....


It uses the new subaru alternator style casing instead of the old one. Difference is the pos output lead is further towards the passenger side, which is why I had to extend the leads.


Here's the alternator's birth certificate.



in these pics you can see old vs new


Old alternator



New alternator




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Well, alternator type is cool too, I meant what Optima you are using :banana:


Also, is it hard to replace an alternator myself? Is it a bolt on bolt off job? Or should I see if I can get a mechanic install one I buy for me.

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I note that your intake, belt guards, and engine decorative cover are all nice and shiny.


Be careful to not use any product like Armour All since it contains chemicals that will harm the oxygen sensor if these substances are breathed into the engine. Silicone is one of the substances that even in extremely small quantities destroy an oxygen sensor.


I have replaced several oxygen sensors that mysteriously failed not long after an engine detailing.

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I have the yellow top battery. I forget the actual part #, but it's the one with dual post terminals.





no I don't use armoral or anything like that. This picture just happened to be after I just wiped the engine down with wet rag. I have used some stuff in the past, but it's silicone free.


I normally don't like to put anything on because then dirt sticks to it, and it's a slimey mess.....

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Josh, here is what you are running...at least according to an older post :banana:


Battery Model: D34/78-950

Part Number: 8014-021

Nominal Voltage: 12 volts


Description: High power, sealed, lead acid deep cycle battery.

Physical Characteristics:

Plate Design: High purity lead-tin alloy. Wound cell configuration using utilizing proprietary SPIRALCELL technology.

Electrolyte: Sulfuric acid, H2SO4. Specific gravity: 1.342

Case: Polypropylene

Color: Case: Light Gray

Cover: "Optima" Yellow

Group Size: BCI: 34



Standard Metric

Length: 10" 254 mm

Width: 6.8" 172.2 mm

Height: 7.8" 198.1 mm(height at the top of the terminals)

Minimum Weight: 43.8lb. 19.89kg

Terminal Configuration: SAE / BCI automotive and GM style side terminal (3/8" - 16 UNC - 2B, threaded nut).


Performance Data:

Open Circuit Voltage (full charged): 13.2 volts

Internal resistance (fully charged): .0028 ohms

Capacity: 65 Ah (C/20)52 Ah (C/2)

Reserve Capacity: BCI: 124 minutes

(25 amp discharge, 80o F (26.7o C), to 10.5 volts cut-off)




CCA (BCI 0o F): 750 amps

MCA (BCI 32 o F): 950 amps

Battery Power (C/2) 8.4 kW

412 W/Kg

955 W/L

Battery Energy (C/2) 624 Wh

30.6 Wh/Kg

70.9 Wh/L



Cycle life:

Cycle Life - deep cycle (BCI): ~ 350 cycles

J240 Life Cycle (BCI): 10,000 - 12,000 cycles

EV, C/2 discharge to 10.5 volts, cycle to 80% retained capacity: > 220 cycles



Recommended Charging:

The following charging methods are recommended to ensure a long battery life:

(Always use a voltage regulated charger, with voltage limits set as described below.)


Model: D34/78-950

These batteries are designed for cyclic applications and for use in vehicles with large accessory loads.


Recommended charging information:

Alternator 13.8 to 15.0 volts

Battery charger 13.8 to 15.0 volts, 20 amps maximum

Float charge 13.2 to 13.8 volts, 1 amp maximum

Rapid Recharge (Constant voltage charger) Maimum voltage 15.6 volts. No current limit as long as battery temperature remains below 125F. Charge until current drops below 1 amp.

Cyclic or series string applications 14.7 volts, temperature <125F, no current limits. When current falls below 1 amp, finish with 2 amp constant current for 1 hour.

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I've had great luck with an excide orbital battery. Same as the optima, just different company. Mine is still going after four years of running a two amplifier, 500 watt system in my car. I just routed a four gauge cable from the alternater to the battery, and the same to the chassis ground, which also helped with the dimming lights.

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