Just bought a 521

[mainer311]

I painted the kick panels flat black. Super pleased with how this is coming out.

 

[thisismatt]

Are the pods open to the back?

[mainer311]

28 minutes ago, thisismatt said:

Are the pods open to the back?

They’re not sealed, but they’re also not open. I cut a small hole right in the middle to pass the wires through. The bottom of the plastic has that rubber “U” edging on it, but it certainly doesn’t form a perfect seal all the way around.

[thisismatt]

8 hours ago, mainer311 said:

They’re not sealed, but they’re also not open. I cut a small hole right in the middle to pass the wires through. The bottom of the plastic has that rubber “U” edging on it, but it certainly doesn’t form a perfect seal all the way around.

Just thinking you're going to lose any low end they might have if sealed. I would vent them into that space behind the kick panel if you can, while sealing the front side with some foam tape perhaps

[mainer311]

12 minutes ago, thisismatt said:

Just thinking you're going to lose any low end they might have if sealed. I would vent them into that space behind the kick panel if you can, while sealing the front side with some foam tape perhaps

I have an 8” powered sub under the seat for lows. I tested the one side tonight and it sounds pretty good. Working on the second side now.

[datzenmike]

Tweeters are extremely directional and define L & R. they would be best at or closer to ear height like on the A pillars where legs won't obstruct them. I mounted mine in my 620 on the dash and the highs reflect off the windshield.

[mainer311]

7 hours ago, datzenmike said:

Tweeters are extremely directional and define L & R. they would be best at or closer to ear height like on the A pillars where legs won't obstruct them. I mounted mine in my 620 on the dash and the highs reflect off the windshield.

That’s how the Rockford system in my xterra is setup. Used windshield for reflection. Most cars do that.

[datzenmike]

I realize that Datsun trucks don't offer a lot of options for speaker placement. The tweeters I had in my 620 were 'biscuit' style and were easily double taped in place. Wires were poked up between dash and glass. 'A' pillar mounts work but the left is almost in your ear. In the '70s my 'subs' were 6x9s in plywood boxes behind bucket seats in my 521. My today's standards it was pretty pathetic but it beat most new cars. The radio option in my new '70 Dart was $38. FM wasn't a thing for another 4-5 years. 

[thisismatt]

Kick pods will give you the "most equal" distances left to right, as far as is possible in a car environment. Air quotes because it's still far from equal. Separating the tweeters so far from the mids definitely then requires signal processing (time alignment) to get sounding correct.

[mainer311]

Here’s the view with me in it. The tweeter is far less obscured than you would think. 
 

[datzenmike]

mmmm not too bad!

[d.p]

My man you got no key chain? Just a key?  Living dangerously I see. 

[mainer311]

41 minutes ago, d.p said:

My man you got no key chain? Just a key?  Living dangerously I see. 

That key stays in the ignition. Actually, funny enough: after I put the L20b in, the truck has so much acceleration, that the key sometimes flies out. It never did that with the L16, haha.

[mainer311]

Well, Drew fuckin jinxed me with the shit alternator syndrome and I had to replace mine already. It was still charging, but the bearings were toast and the shaft was wobbly. Hate when my shaft gets wobbly.

 

And the new hotness:

[d.p]

Just doing the lords work over here. 

[thisismatt]

This is why I stick with junkyard alternators when I can 😄

[mainer311]

1 hour ago, thisismatt said:

This is why I stick with junkyard alternators when I can 😄

Yeah, I don’t have that “luxury” around here. 

[thisismatt]

16 minutes ago, mainer311 said:

Yeah, I don’t have that “luxury” around here. 

Just gotta move to a newer alt.

[mainer311]

Just now, thisismatt said:

Just gotta move to a newer alt.

I kept the old one. I’m going to rebuild it myself. Get some good SKF bearings and see if I can straighten the shaft at all. 

[Stoffregen Motorsports]

I use a rebuilder. He upgrades them with better bearings and can usually mod them for more amps. The most I've ever paid for him to rebuild an alternator and install higher amp windings was $160.

[mainer311]

I paid $28 for this remanufactured one. How good could it possibly be?

[d.p]

56 minutes ago, mainer311 said:

I paid $28 for this remanufactured one. How good could it possibly be?

 

This and there is a local alternator guy here and he is of no help whatsoever.  I have taking a couple to him and never made any difference whatsoever so makes me think what the fuck does this guy even do? 

[Stoffregen Motorsports]

2 minutes ago, d.p said:

 

This and there is a local alternator guy here and he is of no help whatsoever.  I have taking a couple to him and never made any difference whatsoever so makes me think what the fuck does this guy even do? 

That sucks. My local guy is so good, that I don't even buy new anymore. I just bring the stuff to him.

 

I wonder what makes the inexpensive ones fail so quickly. Is it crap bearings or bad re-machining of the cases?

 

One main reason for failure is high RPM use. Even a brand new OEM Datsun alternator won't stand up to constant high RPMs. The alternator on my race car, a Bosch ALRACE1 alternator, is built specifically for racing.  https://www.amazon.com/Bosch-ALRACE1-0124120006-New-Alternator/dp/B00427PMJQ

 

Another reason they give out is wobbly brackets. Luckily for the Datsun guys, the stock brackets are pretty stout, so this isn't usually a problem.

[mainer311]

I have one of the giant cast mounts from a 720 in my truck. The 3-bolt version. So, no issues there. There's a place about 15 minutes from work that I've heard great things about. Maybe I'll just drop it off there. All they do is automotive electronics stuff. Bunch of old timers.

[datzenmike]

7 hours ago, mainer311 said:

I paid $28 for this remanufactured one. How good could it possibly be?

 

I wonder what they really do when they 're manufacture' an alternator? Clean it, paint it and put a sticker on it?