R34 Alternator Rated Output

[kitto]

Hello all;

I would just like to know what the rated current output of an R34 GTT Alternator is. My guess is it will be around the 80/90A range. But i'd like a definite answer.

I have searched high and low on here along with google and no answer is yet found.

Also, does anyone know what the largest capacity RB alternator is rated to and off of what vehicle?

R31 RB30 is 70A - Which is a tad low for me.

Cheers.

[KiwiRS4T]

Here's a brand new 100 amp one for less than what it would cost for a rebuild over here:

http://www.ebay.com.au/itm/Nissan-Skyline-100amp-HR33-GTS-RB25DE-2-5L-R31-RB30E-3-0L-6-Cyl-Bosch-Alternator-/160882378754?pt=AU_Car_Parts_Accessories&hash=item2575564802

[kitto]

Lol, they are in Adelaide as well.

I'm not really sure if they are genuine or not, it says they upgrade the 85A Bosch unit to pump out 106A max. If they do this by changing the wiring configuration to Delta from Star i'm not interested. Changing to Delta allows you to produce more current, but the alternator won't actually start producing charge until engine RPM is around the 1,200RPM mark, so no charging at idle.

[Carbon 34]

Lol, they are in Adelaide as well.

I'm not really sure if they are genuine or not, it says they upgrade the 85A Bosch unit to pump out 106A max. If they do this by changing the wiring configuration to Delta from Star i'm not interested. Changing to Delta allows you to produce more current, but the alternator won't actually start producing charge until engine RPM is around the 1,200RPM mark, so no charging at idle.

80 amps max on Gtt

You can get a place near marion to rewind it not many places around rewind them anymore

, or buy one from usa up to 300amps for $$$$

[t_revz]

Doubt it would be delta unless specified as many people would be dissatisfied. Plus the current would raise more than 20 amps.

What application do you need more capacity?

Bigger battery or capacitor no good?

[kitto]

Yes, true. If it was re-wound to Delta i would have expected a much higher current output as well.

Bigger battery and or capacitor are not an option. No amplifiers or sound system here. Just a fair amount of electrical demand that i want the alternator to be able to cope with easily.

[t_revz]

Fair enough. I rebuilt my alt, ran 0 gauge cable everywhere and did a simple conversion to fit a CAT 880cca battery.

Bulletproof so far!

What voltage are you seeing fully loaded up?

Edited October 15, 2012 by t_revz

[kitto]

Currently 0V lol. Car isn't even built yet. Just to the point of putting an alternator on. I do have a brand new 70A alternator sitting there, but after a quick calc, it seems a little low.

it will really only become a major issue when the head lights are on, rear demister is on etc. With it being a track car this won't be very often. But if there is a larger output alternator out there, i'd like to investigate that path.

[t_revz]

Headlights only being 55w only use 4 amps per side. I wouldn't imagine a demister use more than 5-6

Thermo fans or viscous?

[kitto]

Headlights only being 55w only use 4 amps per side. I wouldn't imagine a demister use more than 5-6

Thermo fans or viscous?

Not when you have 4x 100W bulbs on with high beam haha. 29A there... Demister would be around 10A, Lift pump, 4 or 5A, main pump is about 17A at full load, Thermo fan (if i fit one) will be around 14A (estimate) when it comes on. Heater fan when it get used draws 10A - I would delete the heater if i could find a really effective way of demisting the windows but proving hard.

In retrospect, for the most part, a 70 or 80A alternator will do it easily. Like i said, it will only be night time that the electrical system will be under large load.

[Carbon 34]

Not when you have 4x 100W bulbs on with high beam haha. 29A there... Demister would be around 10A, Lift pump, 4 or 5A, main pump is about 17A at full load, Thermo fan (if i fit one) will be around 14A (estimate) when it comes on. Heater fan when it get used draws 10A - I would delete the heater if i could find a really effective way of demisting the windows but proving hard.

In retrospect, for the most part, a 70 or 80A alternator will do it easily. Like i said, it will only be night time that the electrical system will be under large load.

Thats nothing , I pull 600amps + thru 2 x0gauge not including the car pull all on 80amp alternator

And massive lighting , security draw while parked

Yes its only a matter of time before the diodes give up , but I have a few spares to send off for rewind to 140- 160amps inside the case. The 34 uses internal cooling fins instead of the external ones and smaller frame

it depends how long you drive after pulling it down , a bunch of short trips you need upgrades , long trips plenty of time to recharge

You wont drive with everything on often unless your doing offroad rally at night ?

The old r31 is a friggan nightmare of bad grounds behind the battery and headlights and fuel pump

[kitto]

Thats nothing , I pull 600amps + thru 2 x0gauge not including the car pull all on 80amp alternator

And massive lighting , security draw while parked

Yes its only a matter of time before the diodes give up , but I have a few spares to send off for rewind to 140- 160amps inside the case. The 34 uses internal cooling fins instead of the external ones and smaller frame

it depends how long you drive after pulling it down , a bunch of short trips you need upgrades , long trips plenty of time to recharge

You wont drive with everything on often unless your doing offroad rally at night ?

The old r31 is a friggan nightmare of bad grounds behind the battery and headlights and fuel pump

Errr 600A? I dont think so, Both the battery and alternator cannot supply 600A. 500CCA (Cold Cranking Amps for a few seconds yes). Continuous draw, no. In reality your probably pulling around 150-200A continuous with spikes to X amount.

An Alternator is designed to drive the entire electrical load, once the engine is running, the battery is simply there as a buffer. Obviously with high loads switched on at idle the alternator isn't producing enough current to run all the load, so it is shared with the battery.

Yes correct it will be rare that i drive with everything on at once. R31 wiring is a lot better than many many cars out there. Doesn't matter though as i'm doing a full re wire.

[Carbon 34]

Errr 600A? I dont think so, Both the battery and alternator cannot supply 600A. 500CCA (Cold Cranking Amps for a few seconds yes). Continuous draw, no. In reality your probably pulling around 150-200A continuous with spikes to X amount.

An Alternator is designed to drive the entire electrical load, once the engine is running, the battery is simply there as a buffer. Obviously with high loads switched on at idle the alternator isn't producing enough current to run all the load, so it is shared with the battery.

Yes correct it will be rare that i drive with everything on at once. R31 wiring is a lot better than many many cars out there. Doesn't matter though as i'm doing a full re wire.

Oh yes its more then 600 amps just to two amps and can peak @720amps the car has 2 amp shunt meters with peak hold one in front one in rear

The battery is 2600amps not cca either

The capacitor bank is 100 farad !!

And the batt cap is 600amps instant power alone

And 1 farad cap for the cars electronics inside the fusebox chassis

The sub amp pulls insane power its most likely the only one of its kind in oz and its not the biggest of the brand . The big one is 26,000 watts mono !! and can be strapped together to double that . I'm not talking alpine mate this is serious power 5 times the biggest alpine amp

I think I know a bit about advance electronics and ohms law, degree is it and 25plus years in it

Cca by the way is a pointless measurement in oz

Its design for usa where you base that on cold weather cranking amps , 550 is shite anyway

The battery i run is the most powerful you can buy for 12v market and size constraints and not run li poly or 14v-16v model

And your wrong the current draw can exceed ratings up to the point of blowing a fuse or parts

A dead shorted battery will produce more then rated power till it explodes

[kitto]

I'm wrong in what regard?

To be honest i dont know what amps are out there and i dont really care nor bothered to look into it.

I would like to see clamp meter readings of said current draw.

I dont see the point in having such huge sound systems drawing that much current. Your ears can't handle it anyway haha.

CCA is a bit of a useless measurement yes, but it does give a guideline of what your battery is rated at. Amp hour is what we use.

I'm only using a pissy little 40Ah battery, The only thing i want the battery to do is crank the engine and act as a buffer on idle. Alternator should always do the rest.

If your system is what you say it is, it sounds like you are relying on the batteries (plural?) alone. For a system that requires that much current you would usually put 2x high output alternators on to supply the current.

Yes i know about ohms law, current, voltage drop etc etc. I am an electrician... No not your average domestic one at that.

In what part am i wrong? I didn't mention anything about fuses. A fuse is a protective device, it is to open the circuit under fault conditions to protect the cabling and the supply unit.

Anyway, this is completely off topic, a sound system is not what i'm trying to do here.

[Carbon 34]

Electrician enough said lol

The point i was making is your current draw in your car 70 amp alternator ( r31 gx s3 is 65amp) is enough for what you want to run as long as your battery is up to the task and cables

You wont be driving with max load all the time and you certainly wont want to load the alternator to the max load nonstop or it will fry , the charging system is built for the battery to take the load , the alternator to charge the battery and attempt to keep voltage up to 12v

Ohms law change when voltage is higher ! Say 13.8-14.4 v ( new cars coming will have 24v or more systems they announced not long ago)

Otherwise cars would have 200 amp alternators and tiny batteries!! if you depended on alternators to take the load 100% of the cycle once the car is running , alternators take power off the engine , the more it loads the more power it consumes depending on rpm , you know when it does everything is on , the car idle slows ? Not good on performance cars , but a street car has to compromise power for safety features and comfort

so if you run a 34 alternator or even a chevy truck hd to run arc welders version you still need a decent battery not a water filled junk model, maybe a yellowtop or odessy in the tray size not half size !!

and updated grounds , alternator to fuses, power to starter and all grounds to engine and frame

Nissans and most all cars use crappy thin wire on grounds and main power to save costs and just meets min ratings , they didnt design in a buffer by much for uprated lights, pumps, fans,stereos, etc, the r34 alternator to fuse box wire is maxed out from factory more then 80amps would cause issues on it, r31 is just as bad 10ga wanna be 8 ga if I remember right ? Update it to 4ga !!

Your looking at a very expensive update for no reason , if your car is in proper condition it should be fine , one thing on r31 is no timer or thermistor on rear. window grid , it will just stay on

I had one that has a broken switch and it just stays on till you shut off the car even in 40c days ?, its the ex's car so her problem now lol that item pulls a bunch of current but should only be needed for maybe ten min unless its snowing or lots of people in the car ?

So dont go crazy looking for a huge power alternator just update above

you dont want 100% duty cycle and no way would you in your case for extended time

Yes my car is insane , the battcap is a small battery /capacitor not really what I would call a second battery . A second battery requires isolation from main battery or parallel direct connection same type and model battery to much weight . I have room just dont want to double the weight in drivers front fender side or rear anymore then it has now( carbon fiber used no wood in stereo setup to save weight !)

Yes if it was cranked a long time i would need a much bigger or multiple alternator setup ( r34 dont have room ) but the subs wouldnt last more then a few min before they would catch fire or melt at max power , they see max power for maybe a min tops

The cap bank and setup is a buffer for peaks of current , the voltage would sag below 10v within a min of no engine running it gulps power like a dusty drover in a pub haha

I do have different pulleys to reduce the speed of the alternator into the sweet spot for power output

And so it survives 7500rpm pulls lol

Really i need a high output from usa but the cost is massive without a alternator sponsorship , 2 grand for one you only use rarely is hard to swallow ? Maybe in the future ? billet alloy looks nicer anyway haha

The car copes with the load now ? As long as you drive it past the corner shops

Yes it will make your ears bleed and more if you sit inside cranking it up, i dont it is a demo car for audio spl and i use a remote outside the car for contests , the car is apart right now for refresh ,but i would be happy to show you the current draw at the next show I attend ( cant crank it anywhere near people or police would rock up in seconds) its extremely loud !!! But also sounds good on low volume for sound quality shows

Sadly i dont have the car back together for extreme hp show but

Just look and follow the ground shake for old grey haired guy cranking Korn, linkin park or some off the wall music lol

Stupid maybe but

it works just like a crazy powerful engine

You only use it once in a while and both will get you in trouble if you do in public

Both will get your car impounded and fines galore if used wrong

so if you want a diagram of updates to make so you dont have to waste a mint for no reason I would be happy to prove one if your interested ?

prob post one for sticky in car audio section anyhow ?

Edited October 15, 2012 by Carbon 34

[kitto]

That post was a little difficult to read. Bit all over the place lol.

Yes i'm an Electrician, enough said. I know what i'm talking about and what needs to be done. Like i said, i'm not a domestic electrician who doesn't know the difference between a relay and diode.

Yes i worked out that for most of the time the 70A alternator will shit it in with no issues what so ever. My simple question was to ask what the output of the R34 Alternator was, 80A was my thought, i also wanted to know if there were any larger off the shelf alternators around that came off of other RB engines.

The battery's primary job is to crank the engine, it also does help to supply power to the vehicles electrical system under heavy demand. The alternator has two main jobs - Charge the battery at a regulated 13.8 - 14.4V and supply power to run all the vehicles electrical systems. Why do you think alternators have such large output current these days? Because of the large demand from all the cars electrical systems.

No you do not want to run the alternator @ 100% duty cycle or close to it for long periods of time. And most people wont.

Yes, the higher the voltage the lower the current. Ohms law. Current is inversely proportional to voltage. As your voltage starts to drop, your current starts climbing and vice versa. The higher the operating voltage of any particular electrical system in the world > the lower the current draw from that system.

Ps, we're in Australia, here we use mm2 for cable sizing. not AWG.

[Carbon 34]

No kidding were in australia but you do still buy wire in awg sizes mate unless your working on a/c instead of d/c , rarely would car shops know the metric or how much current it can handle @ temp , its cheaper and a better option to use car audio wiring ?

anyway you know so much but ask the question here is beyond me ? if any Rb engine had more it would be GTR 34 or the 4x4 trucks but the alternator should fit a bunch of cars /trucks besides nissan and vise versa most are bosch or mitsubishi brands

so finding one off a luxury car would be a more powerful option ? Or maybe a jdm cargo van ?

not trying to be a dick just open your mind into what is possible and still safe ? you can cuss me another day lol

[R.3.2.G.T.R]

r32 gtr one is 90amp

[kitto]

No kidding were in australia but you do still buy wire in awg sizes mate unless your working on a/c instead of d/c , rarely would car shops know the metric or how much current it can handle @ temp , its cheaper and a better option to use car audio wiring ?

Errr, doesn't matter if its AC or DC. Cable is cablem, it has two insulation ratings for voltage and a current carrying capacity. AWG is still used widely in the automotive industry but in the electrical industry its all mm2 which is so much easier. As we work to an Australian standard, we know what size X cable is rated to current wise and we choose a cable accordingly. De rating factors come in to play here as well.

I get cable for pretty much free so i'll be using mm2 cable. Cheap, yes it sure is a lot cheaper than automotive cable.

anyway you know so much but ask the question here is beyond me ? if any Rb engine had more it would be GTR 34 or the 4x4 trucks but the alternator should fit a bunch of cars /trucks besides nissan and vise versa most are bosch or mitsubishi brands

so finding one off a luxury car would be a more powerful option ? Or maybe a jdm cargo van ?

not trying to be a dick just open your mind into what is possible and still safe ? you can cuss me another day lol

Yes, a luxury vehicle would most likely have a higher output alternator. I would assume the R34 GTR would have one of the highest output alternators that will bolt onto an RB.

I wasn't cussing you.

r32 gtr one is 90amp

Cheers dude, i think most later model skylines will be around that figure as well.

[t_revz]

Heater fan when it get used draws 10A - I would delete the heater if i could find a really effective way of demisting the windows but proving hard

Window down half an inch?