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90 amp bolt in alternator on an L-series motor


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I discovered that a ka24e alternator is 60amps but if you get a new on from Shucks it is a 90amp-105amp (or so they say, steve the engineer would now how to check :) ) for 180 bucks remanufactured in the US and it has a life time warranty (Job security for a few people :) ) Well after I brought it home I compared it to my spare SR alternator. They where the same except the pulley. The KA24e from the truck has a v belt style pulley all of the s13's have the wide belts, mini serpentine's I guess..... I also compared the bolt spacing, yep the same as the L and the SR. I'm not to surprised.


The V-belt was to long, it may have been due to a very worn out belt. We went from a 37 inch belt to a 36.5 and it fit perfect. Even some room for adjustment. I think the belt must have been super stretched because a 36 was way to short.




Starting from the left: 35amp 521 alt. 60amp z alt and a 90amp KA24e alt. Notice all the spacings are the same.


So with a little wiring you can have a IR 90amp alternator in your dime. A little more work you can have it in a pickup :D


To get it to fit in a truck.......(anybody??) I think Redeye form NWDE used a ZX lower outlet to give the bigger alternator more room. Wurker/slodat/ratwagon does a saturn alternator. It does require a custom upper mount.



The wiring is simple... I will do detailed pics when I find the memory card for my camera :( I may just buy a new cheapy one, I'm so sick of my cell camera....

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I used a 65 amp GM alt in mine, had to make a custom bottom bracket, but it fit without having to change the water neck. Be careful with the schucks alternators, they have a lifetime warranty for a reason.....because they take a shit every 6-9 months. I had one on my beretta and they had to give me 4 free new ones for the 5 years or so that I had the car! I always try to get electrical components from NAPA, they may not have a lifetime warranty, but they last forever.


Ice, it looks like the z alt is longer from the bottom post to the top post than the other 2?

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For the truck guys (especially those running L16/L18) if 60amp is good enough for you there is one solution for internally regulated alts.


Importedcarparts.com Order the BOSCH alt for a 1978 Datsun 200SX. They list a high output one. Stock is 50amp, Bosch rebuilt them to 60amp. They are a diameter larger than the truck alt on the left but smaller than the Z alt. They fit great (bolt right in) and clear the idler arm bracket. Order the 200SX belt with it though for proper belt fitment.

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I have used a z alt on my previous wagon and it was "ok". I was running H4s with an upgraded, independant, headlight harness. The lights would dim at night when idling, probably the wrong size pulley. On my new wagon I am gonna do H1s with an HID upgrade and the upgraded harness (same as before wih 2 relays low/high), so I think the KA alt will suit my needs better, if I get the right size pulley.

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I always try to get electrical components from NAPA, they may not have a lifetime warranty, but they last forever.


The Schuck's alternators are about the lowest quality you can buy. All of the big "rebuilders" use the cheapest components available - bearings, rectifier diodes, etc. They work for a while. The way the company makes money is a numbers game. Very few people return them when they fail. The average person then goes to a real mechanic or auto electrical shop and pays for a quality alternator.


My advice is to either use a used, ORIGINAL OEM alternator (ie: the alternator that came on that 1990 whatchacallit) or pony up a few extra bucks and go to the local Joe Car Dude's Auto Electric. If they are worth a shit, they will let you make any applicable choices before they build the alternator for you. The reason I am a fan of the Saturn alternator (which is a GM/Delco CS-130) is there are hundreds of millions of them on the planet. It is a VERY good design. High output at very low engine speeds. All you need from the Saturn is the case. An alternator shop can build it to ~100a at idle and 150-200ish at speed. The range quality of parts for them is huge, so you can get high quality bearings, over sized rectifier diodes, etc.


End result. That cheapo alternator will leave your ass stranded on the side of the road in a second. Their warranty doesn't cover being stranded on a rainy night after a shit day at work. They just give you another all costs spared "rebuild".

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Steve, Kevin, the Bosch remans are junk. I bought one and had it fail 3 days out of warrantee. I got a "courtesy" 50% discount on the replacement, however ...... I agree with Steve, if a new part is available, by all means get it, one of the old, original 35amp Hitachi's I have as a spare is still working fine after umpteen gazillion miles and 35 years!

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Jason, I thought I had written about the Bosch in the above post. I forgot. The Bosch remans are just el cheapos in a Bosch box with a Bosch sticker. They are complete junk. Like I said, that stuff is a pure numbers game for those companies.


ANY good alternator shop will build you an incredibly superior alternator.

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After my last experience (it faild about 150 miles from home!), I'll have mine re-built by a local shop here in Richmond. There work is superior and their customer service is excellent. I'm sick and tired of the re manufactured junk I buy failing. On that note, anyone got any idea of where I can buy a stock 3/4" "new" brake master cylinder, all I can find right now up here are re mans "shudder".....

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also, do you folks have a volt meter installed?

I put one in my truck and it gave me a good warning a few days before the original 35amp alt died. I happened to be coming back from a trip to Oregon when it started to act up but at least I had an idea what was going on before my battery was just dead on the way to work one morning. :) My Z has a volt-meter from the factory.

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A voltmeter is the best indicator of what is going on with the charging system. If you don't see > 13.0 vdc on the voltmeter, you have a problem - PERIOD.


This is based on physics. A lead acid battery has a nominal voltage of 2vdc. Your battery has 6 cells. 6 x 2.0 = 12vdc. In order to charge a lead acid battery the vpc (volts per cell) must be ~2.20vdc. 6 x 2.20 = 13.2vdc. If you charge a lead acid battery > 2.45vpc YOU WILL DESTROY the battery. It is only a matter of how long. Extended time will cause multiple problems that lead to plate shorts, etc.


So, the way to "test" the charging system:


1. Start the car.

2. If you have the popular ZX "upgrade" (which it is not much of an upgrade), rev the engine up >2k rpm to ensure the regulator turns on

3. Give the charging system some load - turn on the headlights and heater.

4. Check voltage at the battery posts

5. If it is 13.0 - 14.1 with a load on the system (accessories on) you are in good shape.

6. If it is less that 13 you have a problem. It will not go away.

7. If you replace a component in the charging system take the extra 5 minutes to install smart upgrades. A LOT has changed since '73 with respect to auto electrics. There are a rare few concourse datsuns in the world. Only an idiot will "go back to stock", so don't even say that BS.


What I would call "smart" upgrades:

1. Modern alternator with 90a or more output of good quality. Modern is not a 25 year old ZX design that is a minor improvement over the stock externally regulated 35a Hitachi

2. Install relays on the starter solenoid line and your headlights. You don't need HID's, you need full battery voltage at the headlight.

3. Upgrade the output wire on the alternator and get rid of that problematic factory splice by the alternator.

4. If you don't know what you are doing, get some help.

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These days I wandering farther and farther from home with the 510's. Heck, our club "cruises" are about 500 km's in a day now. I'm going to have to install the whole shebang I suppose, volt, temp and oil pressure, just to see what's up. Mind, the alternator packed it in on one of our club cruises on the way back. I just managed to limp home and figure it out. All of the 4500rpm running must have did it in.

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The rpm comment made me think of something else. You can't spin an alternator above about 12k rpm and expect it to live very long - the bearings aren't designed to work above that speed. Two options, if you have a high revving engine, size the pulleys appropriately OR use a common case alternator (like the CS-130) and source upgraded bearings that are made to spin at higher speeds. Option one is probably the easiest.

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If you believe the local rebuilder has this covered now, after we figured out what killed mine, a couple of the guys went down to the rebuilder and spec'd out a nice alternator rebuild that would live on our engines. It even costs less than the Bosch re man, go figure that one Steve...... Sizing the pulley for lower rpm does help, however, some of the guys that have gone this route have reported "brown outs" on some more sensitive electrical components at idle in traffic.


Our club cruises average about 4 per year and any stretch of highway driving (like my runs down to Seattle from here) will see 4000rpm for pro longed periods of time. I'm at about 80mph or about 130kph at that rpm in 5th gear and I'm still getting passed by everyone. I'm running a dog leg 5 speed with the stock rear end and 14" tires too.

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I have yet to see a set of retrofitted/aftermarket HID headlights that are anything other than an eyesore. I am all about cool factor as well as doing things for no other reason that that's what a guy wants on his rig. My thing with these damn headlights is they are blinding to other drivers. My pal OregonDime was over sporting his new $400 investment on his 510 the other day. Damn things hurt my eyes just looking toward the front end of the car. Noticed the same thing driving home from Tacoma the other night on the front of a riced out (or is it 'sport' bike) sewing machine bike the other day.


My $12 Sylvania halogens illuminate the road better than most anyones setup, at least to my eyes. But I know how to lay out wiring so things work at their best. ie: relays placed at the correct point in the circuit, properly sized conductors AND grounds.


My .09 on ricey HIDious headlights..


Note: my opinion, don't take offense to it.

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As is said in my disclaimer above, just my opinions. I have a set of the BMW projectors and have seen a couple of sets with a "normal/stock(ish)" bulb installed that I thought were good.


[WARNING! - RANT] Something that turns me off about "car guys" that are more accurately described as people who want to appear to be the person that built their ride or had an original thought and actually made something on their ride is the guys who read too much on forums, web sites and magazines and know shit squat about a fucking thing when it comes to cars, or probably anthing else for that matter. The douche bags that Hainz rants about. The fucking twit with $800 worth of headlights in a car with a charging system that can't keep up with a damn flashlight battery, let alone run his Ricey McRicerson headlights. You've seen it the "sick ass slammed 510 with heated springs" and all the moron can tell you about the car is his plans for an SR20DETTT with an 8 speed and 18" brakes - you know like so and so's car. The guy that reads 10% of a thread that has many hours, probably on the order of hundreds of hours of work, research, try and try again to get something sorted out right and well excecuted. Ricky Dipshit cheap fuck Datsun Dick pays triple price on eBay for his kewl part and doesn't know how to run a drill, let alone install his $60 "tricky dicky hood struts". So, now he has 250# struts on his hood, which he can't close.. well he can't close anymore - because he folded it in half the first time to overcome the force of the strut. He also has 9 sets of holes because he didn't actually look at the photos or heaven forbid take 10 minutes and lay it out before drilling a 1/2" hole for a M6 bolt, that he cross threaded a SAE nut on.


Here's a tip. Buy a fucking Honda, go to Wal-Mart and accessorize to your un-original hearts content! You will be in like minded company at the pull apart looking for that coveted JDM B16 blah blah.


Yes, I got an email from some fucker who did this to his hood and told me I should have gave more details because he has to get that much needed carbon fiber hood now and put off his $3k T3/T4/T-FUCK-YOU turbo purchase - that he's going to put on a 100k mile stock L20 - you know to "see what it's like".



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Hmmm... dont know where all the hostility is coming from, up till this point I thought you were a pretty cool guy, never had a problem with you. Kinda seems like you are accusing me of being the type of person you are ripping apart at this point, if you are you couldn't be more wrong.


You are welcome to your opinion. I had h4s, like I said, on my old wagon and they were great... but I want more, and I can afford it. I guess I'm also a moron cause I'm doin LED taillights cause I want people to to actually see my car at night time from behind... guess it offends you that I'm making my car my own. I dont see the need to justify my abilities to you since you've never even met me, but I'll say this and leave it at that... I'm 27 and been working on and around cars for more than 20 years. I have wanted a 510 wagon since I was 6 years old, and 510s are a family tradition so to speak.


I see nothing wrong with hondas, only the people who stand as the majority of what hondas "represent" which why I got out of them. I had a completely stock "looking" one that was fast enough to get me into the kind of trouble that forced me to sell it. I bought it as a project from some "kid" who couldnt finish it and got in way over his head with it. I built a wiring harness for it from scratch... I know my way around spool of wire well... Had it running within a week of getting it and was driving it daily within 2. The guys dad was really pissed and even wanted it back, I bought for 1/10th what they had into it...


I have had 5 510s since I started and all of them were non runners when I got them, one sat in a barn for 12 years... and I got it running on my own at 17. Bent and installed ALL new brake hard lines, new gas tank, new brakes all around, new mc, did my first vw radiator (and learned they suck).


If you really wanna talk "unoriginal"... lets talk 510s, nothing you could ever possibly do or dream of doing is original on 35+/- year old car.

Bah... I'm done...

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Calm down there hot rod. You are I clearly explained the entire situation. If I wanted to say something about you, I'd send you a PM. I was, as I stated, ranting about a guy emailing me because he is a bonehead. I put it in this thread, because it seemed related and I got the email about 10 minutes before.


I'm with you, no need to flex muscles on the internet. I have 3 engineering degrees. Now what? I'm not a prick and made an earnest attempt to communicate something and point out the nature of the post.


In regard to the unoriginal comment. There's VERY little that is original. There are almost 6 BILLION people on the planet and people strive to be "different". There are a LOT of 510's in the world. I'm happy having my example.


My little temper tantrum was about a significant contingent of the Datto folks that should probably be tested prior to being allow to operate a door knob. Yet, the buy an SR20 and post post post on the forums questions that could be answered with 1 drop of initiative.


Please, don't take anything I say personal. It's not personal, at all.


With respect to "knowing way around a spool of wire". Please understand there is a night and day difference between being able to connect stuff up and it "work" and engineering. You stated you saw no reason to explain your abilities to me, yet you do it anyway. I'm a pretty straight guy. Please proofread your work before you get all uppity, it makes you look bad.

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Mr Engineer, the next time I see you I'd like your opinion on my headlight setup. You mentioned relay placing and conductors. I just threw in two relays and some larger wires to power my H4s. They work but honestly I can't tell any difference in light. At least my factory wiring won't get cooked again. :eek:


Maybe I need better quality bulbs. I've run the same bulbs now for over 5 years.

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