Jump to content
SAU Community

Replacing Alternator With More Powerful Alternatives - Help Needed

Dose Pipe Sutututu
 Share

Recommended Posts

Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted (edited)

Hi All,

Before you flame me, yes I have searched, and there's no conclusive information either on SAU and on Google.

I own a RB20DET from a R32 in my S13.

Problem: Alternator not charging properly, causing unneccessary engine stalling and a flat battery

Observations:

  • When alternator is warm voltage drops to 12.5 volts from 13.5 volts (still very low reading)
  • When all my 3xthermos kick in, car will hesitate and voltage will sit flat at 12 volts
  • Alternator light does not turn on, i.e. alternator not 100% dead but not charging
  • When car is revved past 3k voltage will bounce up to to around 12.7 volts which is still pathetic

I want to replace my alternator with something more beefy, as the stock RB20DET alternator only outputs a max of 70amps, which isn't enough provided the stereo & thermos alone would draw that much current. I was thinking either a RB25DET or a total aftermarket replacement.

I have read elsewhere that it is possible to use 120AMP Bosch alternators found in the cop car which is universal as per link:

http://www.calaisturbo.com.au/showthread.php?t=11447

apparrently all you have to do is switch the pulley over... and it will fit. Guys on the forum are saying VS commodore alternators fit onto RB30s, i.e. will fit on RB20 Rb25s someone please confirm?

And I've been reading that RB25DET alternators, rated at 90amps will fit RB20DET, but no one has confirmed that the rear plug will plug in or if there maybe some cutting and shutting required.

What do you guys suggest? RB25DET alternator will suffice? I'm just really concerned about it dying on me in summer with all 3x thermos kicking in, A/C on max, headlights on.

Cheers,

Johnny

Edited by johnnilicte
_Scotty_ Collaborator

_Scotty_

Posted
Posted

I recently replaced the alternator on my RB25 with one off another nissan rated at 100Amp. Not sure exactly what it's off (possibly Z32?) but the part number is ARJ036. The standard one I pulled off was only rated at 80.

I don't know whether there's any difference in fitting to an RB20, but I'd be suprised if there is. Even if the plugs do need changing it's a pretty simple job for yourself or an auto sparky.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • The Bogan
      NC MX5

      By The Bogan · Posted

      Damn it, I was at work last night, and stayed in a room there during the storm with the car outside, but undercover, I just went downstairs and well....there was a large steel locker that has come from some place last night, it wasn't anywhere I could see yesterday, and yeap, it landed on the fraking car....of course it did..... LOL So, I'll need to take it back for paint and panel, luckily it was only the boot that took the hit, so it could have been worse Serves me right for staying at work and getting on the cans with some of the boys
    • The Bogan
      NC MX5

      By The Bogan · Posted

      Yeah, really happy with how it all turned out As for aftermarket lip, nah, I'm not really a fan for practically reasons on a street car that gets driven everywhere  I did have the full lower kit on my 2015 STI, but found the front lip scrapped alot, even at stock 4x4ish ride height As the NC sits now, with the lowest point of the car at 110mm, so just legal, some steep driveways and steep speed humps will still "just" scrap those little plastic OEM air dam thingies on the undertray just before the front wheels
    • Dose Pipe Sutututu
      Hypergear Turbochargers and High flow Services Development thread

      By Dose Pipe Sutututu · Posted

      Here's one I help build and tuned a decade ago, Garrett  GTX3071R Gen 1, T3 twin scroll 0.83 rear housing. Went from larger 272 cams down to smaller Tomei Poncams to help with the low end. S13 non VCT motor. Car was purpose built for the track, hence low down was the focus. Note the actual dyno chart shows lower boost, however the EBC and boost gauge showed 1.9Bar (Ignore the torque, I was young and didn't know how to set derived torque)  
    • hypergear
      Hypergear Turbochargers and High flow Services Development thread

      By hypergear · Posted

      I’m doing some side developments on SR20det S13 engines, its one my hobby cars used it to compare flow capacity of some smaller size wheels. SR20det is one of another JDM legendary engines I'm sure there are plenty of SR enthusiasts on this forum, I will share results some common turbo configurations here. a quick run down of what the car is: Wide body 180sx Type X with black top engine (blue). It has: Stock bottom end Haltech 1500 ECU 5-0 motorsports trigger kit Kelford SR20DET Beehive Spring with Titanium Retainers Kelford Cams SR20DET S13 188-B 268/272 Cams G25-660 Turbocharger in T2 .64 rear housing internally gated ARP Head studs MLS head gasket 1000CC ID injectors Walbro 450L Fuel pump Front mount cooler kit JJR’s 3 inches turbo back exhaust (its too short for the 180sx it had to be extended) Pump 98 fuel Hub Dyno tune So far made 270rwkws at 22psi full boost by 4500RPM. Engine is very knock limited hence a pretty bad looking top end. From previous experiences it seems like SR20dets are happier with bigger size turbine, some thing like a GT30 would make way better top end, but on same time response is lost. It won't be a problem with S15 VCT engines. I'll be testing alternative turbine housing, turbine wheel and possibly dump pipe options for extra flow to resolve the problem and of course E85 would resolve all the issues.            
    • cardre
      My R32 Money Pit & The Headaches That Come With It

      By cardre · Posted

      Awesome writeup and details. Thanks for sharing the story so far. I can relate to parts of it with my previous car and some of the issues I had to deal with.
×
×
  • Create New...