If you have a 3-rib alternator (some EB's don't, dodgy engine recon shops) the EF one will fit straight in. Just it may squeal if you run a big sound system at full piss as the 3-rib belt won't have the grip. For a normal car it's no drama.
I have one amp, thermos, and a 80amp EA alternator in well my EA GHIA, and at full everything running, stereo, full high beam including 2 spot lights, thermo fans on, A/C on, door open, and boot open, I get 13.4 volts to the battery, and with everything off I get 14.5, hope that helps :0)
Firstly, the 3 rib pulley is way to thin to have a proper grip due to the increased load, it'll squeel even if you put your high beams on. Trust me, i've been down that road, and ended up installing the whole single drive belt system to overcome the headaches caused by trying to fit the larger alternator (cost me around $1100 ). Secondly, the mounting arms are different, so even if there were no problems with grip, you would need to get a custom bracket made up to mount it. Best option is to get yours rebuilt to 85amps and a good drycell battery.
No I had an EF alternator and the arms were at different angles to my old one, the EA one had it's arms at 180 degrees to each other with the EF one having about 30 degrees difference. We've tried two seperate EF alts on two cars already and all we get is screeching whenever a load is put on it. I don't know what kinda alternator you must have. Is the casing on yours larger than on an EB alt?
I definitely have an EF alternator, pulled it out of the EF myself
Same for Matt (auscarnager)
110 amp, Mitsubishi, 4 rib pulley.
I dunno about the casing size, looks similar though.
I also have an AU alternator on an AU motor on the floor, the arms on that are different as it is designed to mount onto the more solid AU sump.
As I said, the demands we put on it aren't huge, fairly moderate. This may be where the problem you have is - looks like you spent a few grand of your stereo!
thanks all for replys. i think when i have put the stuff in i'll see if the altenator can keep up. if it can i wont worry about it. if it can't then it looks like i have some headaches to look forward too.
Get a multimeter and check the current performance, then load the system up headlight full beam, fan on high. a/c on high, door and boot open, hazards and current stereo on, check the drain if it goes below 12 then you are facing a problem, not that one would run all that at once normally, but ya never know.
isnt the gauge on the dash accurate? but will try the multimeter anyway. when i get my car that is. on my EA when i had stereo, high beams, fan etc the gauge would drop to 12 volts. but that was on idle it would go up to about 13 when driving and that was with no thermos.
really u want the most volts up to ~14.4 at the battery, with full load. this way u supply the amp/head unit with more power and therefore increases the power output of them.
there are many other advantages such as not having to turn the volume up as much to get closer to deaf and longer battery life.
a 13.4v charging rate isnt really enough to keep the battery fully charged. 13.8-14.4v is the prefered rate and battery will last longer from it. Though for short amounts of time 13.4v it is alright.
mongrelEB - how did you get the EF alternator to fit, was it just the pulley and thats it?