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Well, stage one is complete. The optima yellowtop is installed and working great. The Alternator is built, and should be in the mail on monday. Ill add to this post when I get it.

Here is a blow-by blow account of how it went.

Bought the yellowtop at Costco. It's a D34/78, 750CCA, 55Ah. Cost me $189 CAD, which is more than you'd pay in the states, but less than any other stores in Canada.

Took it home, let it trickle-charge overnight with a shop charger (didnt know they came charged)

Test-fitted the factory rings with the OEM battery still in the car. This is where I made my first mistake. I assumed both terminals were the same size, so I test-fitted the negative ring on the postive terminal, and of course it didnt fit. So the battery remained in the garage until I got home from school today, after stopping at my favourite car audio place to pick up the battery terminal equivalent of a distribution block.

Took out the OEM battery, carved up the OEM cables to fit them into the distro block, and realized the starter cable was about 2 inches too short, I was expecting this, because of Lauren's thread, but unlike her, I couldnt stretch it. The stereo and main power line fit fine, and the block fit great on the terminal. So, stuck 15 miles out in the wilderness with no other car, I improvised. Unplugged the stereo line from the 50 amp inline fuse, and plugged in the hacked up starter cable. Car starts fine. Drive 15 miles to Canadian Tire, pick up a 55" 2ga copper starter cable, and come back.

I had to remove the intercooler to get to the starter, so if you havent installed a TMIC yet and you're planning on putting in an optima, I suggest you change to a longer starter cable now. Starter cable goes on, thread it through the misc other piles of crap, and plug it into the distro block. Everything runs great. I havent really messed with the stereo yet, but the car feels noticeably smoother. Dont expect similar results though, my battery was in extremely poor condition, so the difference is very relative.

Pics:

You're welcome spunky. Looks good!

When you can afford it get the matching negative terminal.

There are a lot of things I'll get when I can afford them

ugh, gold batery terminal. dont mean to shit on you but I can get into why gold terminals are not the way to go if anyones interested.

Polished copper

oh ok.. I'll save my gold terminal rant for another time...

Trust me, I wouldnt waste my hard earned cash on something like that

what kind of HO alt did you go with? how much was it? im looking at putting my large system in soon and 70 amp alt is simply not enough. already got the yellowtop in, swear by em since i got it. can play my stuff at nearly full tilt with engine off for 2 hours till it cuts out from voltage drop and STILL start my car.

Same as Josh. Guy in Houston makes them to order

160 amps at peak, turns on at 500rpm. Dunno how much it puts out at that level, but I'd expect at least 70 amps.

The guy is in Dallas, but yeah....they'll work. There's a little bit of modification to the main power leads, and sensor connectors.

Josh, got more info? Legacy and Forester are in dire need of alternators. Forester needs a battery VERY badly too.

Phil,

I can email you the guy's name & email address if you'd like.

Here are a couple threads that talk about some of the issues I had to deal with.

http://bbs.legacycentral.org/viewtopic. ... ernator%2A
http://bbs.legacycentral.org/viewtopic. ... ernator%2A
http://bbs.legacycentral.org/viewtopic. ... ernator%2A

Also, not sure if this was posted in any of those threads, but here's the test sheet.
http://www.main.experiencetherave.com:8 ... ortest.jpg

Cost is around $300, and there's some tweaking that needs to be done to the wiring to make things fit.

I would really like to see a weather tight connection/plug be used. I'll email Chad and see what he says.

Hmm, if I read the test sheet correctly, the alternator produces nearly nothing at idle? That can't be good...

Most alts dont produce anything at idle, they dont switch on til 1100 rpm

I had them wire mine up to start at 500rpm

Yeah, IIRC it's a purple wire that signals it on.

Steve

You have to remember too that the rpm listed on there is the alternator RPM, it will be higher then the engine rpm.

I swapped around some pullies to ensure that it was turned on at idle.

I shot chad (guy who's selling them) an email regarding the turn on speed, and it sounds like they can make them lower. Other thing to note is that with HO alternators, they don't make as much amperage at lower rpms when compared to standard alternators. That's just the way they are.

So I'm trading low-end for high end?

I'd love for it to produce more juice at lower RPM, but don't want to sacrifice longevity for it. Not much way to do that I suppose.

Josh, you got a handy Excel spreadsheet that will calculate amps at idle, 3500RPM, and 6500RPM for OEM and this alternator (and different pulley sizes as well)?

I need more than I got, but I like my idling, and such.

Alternator speed (RPM wise) is about 3x what your engine RPM is. For example, if the alternator's RPM speed reads 2000, that's around 650 engine RPM. So the alternator is producing good power at low RPMs. As you get higher in the overall amps of an alternator, it will produce less and less percentage wise of its total capacity, when at idle. If you have a stock unit that produces 70 amps, it might produce 45 at idle, or more than half of its total capacity. If I sold you a 150 amp alternator, it would probably produce 60-70 amps at idle. Still more than stock but suddendly we're not over half total capacity, but under. The alternator I had build for Splinter turns on slightly below the vehicle's engine idle RPM. We can't get it much lower than that.

Chad

I don't have a spreadsheet that will calculate amps.

I have this one that gives rpm with various pulley configurations. It may seem confusing, but I used english & metric units....I don't know why.

http://www.main.experiencetherave.com:8 ... _calcs.xls

I could probably whip something together with the amperages, but I believe Chad has addressed your questions.

GOt the new alt yesterday, installation was a snap. It helped that I'd already taken out the AC compressor, but it was literally like 3 bolts. Dropped right in.

Im a little concerned though, the plug was identical to the old one, Josh said it should be different.

Anyone know a good brand of high output ammeters?

I talked with Chad. With your alternator, he was able to utilize the same plug, rather then the kind mine was.

I wish mine was like the one you have. He said I could send my old one in to be re-wound, but I don't feel like messing with it.

Sweet

Im driving it tonight, Ill crank up the system and let ya'lls know.

For the curious:

Did you get a test sheet like the one I got?

Nope