11 replies to this topic

[PartySausage]

Hey guys as alot of you know ive finaly got all my speakers and amps but now all i need is something to power them perfect.

im thinking of wacking on a 70amp altonator with a honda civic type r battrey which fits in the standard hole with an ampage rating of 680 from the top of my head

do i need to change anything else when removing the old altonaator to the new one?

going to change the wire from what ever gauge is standard to 0gauage

anything else?

[danrock101]

fan belt just incase for the price of one it's worth doing

Edited by danrock101, 20 January 2010 - 04:52 PM.

[WiredbyWilson]

Why would you need to change the wire? All late MPi minis ran a 70A alternator and IIRC all minis have the same batter to starter main cable.

[PartySausage]

Why would you need to change the wire? All late MPi minis ran a 70A alternator and IIRC all minis have the same batter to starter main cable.

apprently from what i hear which ill tell you as soon as i stick a tester on it.. you get 25% increese? as im running a orion hcca 10" sub that needs 1500WRMS

[WiredbyWilson]

Why would you need to change the wire? All late MPi minis ran a 70A alternator and IIRC all minis have the same batter to starter main cable.

apprently from what i hear which ill tell you as soon as i stick a tester on it.. you get 25% increese? as im running a orion hcca 10" sub that needs 1500WRMS

you get an increase in what though? the alternator can only give 70A so it won't give you anymore power by running a different cable.

thing to remember with wiring to amps also is you are fusing the WIRE not the AMP. a common misconception (apologies if teaching you to suck eggs)

[WiredbyWilson]

Why would you need to change the wire? All late MPi minis ran a 70A alternator and IIRC all minis have the same batter to starter main cable.

apprently from what i hear which ill tell you as soon as i stick a tester on it.. you get 25% increese? as im running a orion hcca 10" sub that needs 1500WRMS

Also to run 1500W you would need the following power

12volts x 125A

Does the amp you have have 125A worth of fuses?

[PartySausage]

Why would you need to change the wire? All late MPi minis ran a 70A alternator and IIRC all minis have the same batter to starter main cable.

apprently from what i hear which ill tell you as soon as i stick a tester on it.. you get 25% increese? as im running a orion hcca 10" sub that needs 1500WRMS

Also to run 1500W you would need the following power

12volts x 125A

Does the amp you have have 125A worth of fuses?

its all to go in but yeh the amps a orion d2400 rms of 1500 at 1ohm ogauge wire and theres 3 x40amp so yeah thats about right i guess

yeh back to the 0gauge im gona try it and see what readings i get befor and arfter i shall tell you results it seems pritty common sence to be honest.. bigger wire bigger flow

p.s mines a 1979 mini running with the standard altonator so my would just be on the safe side and change the wire for bigger amp raiting.....

Edited by PartySausage, 20 January 2010 - 07:14 PM.

[WiredbyWilson]

more wire also can result in more heat and resistance.

i would also excercise caution running stereo amp wire under the car as I don not know if the coating is up to the same pounding as a pre-designed cable.

again i am interested in results as i can't see how bigger wire will harness anymore power from the same alternator.

[PartySausage]

Yeah i wil let you know buddy! gime a couple of weeks

and ive relised ive made a mess of the topic title haha should b changes to alto not amp DURH

[pbrain]

4 guage cable will do the job for what you're doing. The main power surges will come direct from the battery which i presume is very close to the amp. The cable from alternator to starter, i wouldn't alter. The existing alternator to battery cable should be sufficient (70amps). I would put in a fuse between alternator & battery, i fried an Astra alternator (80-90amp) with a pair of DLS CAD1000s so you're close to the knuckle.

the WIDER the cable the less resistance (higher current/amp handling)
the LONGER the cable the resistance increases (in a car i wouldn't take this into consideration...cheap electrical 2.5mm cable over 100 Metres only as a resistance of 0.5ohms, so chunky car cable around 3-5 metres i wouldn't think about it)

The only reason i'm using 0 guage is my main amp uses around 800-1000 amps fully cranked

[PartySausage]

4 guage cable will do the job for what you're doing. The main power surges will come direct from the battery which i presume is very close to the amp. The cable from alternator to starter, i wouldn't alter. The existing alternator to battery cable should be sufficient (70amps). I would put in a fuse between alternator & battery, i fried an Astra alternator (80-90amp) with a pair of DLS CAD1000s so you're close to the knuckle.

the WIDER the cable the less resistance (higher current/amp handling)
the LONGER the cable the resistance increases (in a car i wouldn't take this into consideration...cheap electrical 2.5mm cable over 100 Metres only as a resistance of 0.5ohms, so chunky car cable around 3-5 metres i wouldn't think about it)

The only reason i'm using 0 guage is my main amp uses around 800-1000 amps fully cranked

ah thats helped out a bomb, not going to consider wasting my money on 0gauge then if i dont need it i need it for my amp and sub but thats it.

i would of loved to of seen if the 0gauge wire would of made a diffrence tho...... what fuse do you reccon is needed?

my amp rms is 1200

[pbrain]

4 guage cable will do the job for what you're doing. The main power surges will come direct from the battery which i presume is very close to the amp. The cable from alternator to starter, i wouldn't alter. The existing alternator to battery cable should be sufficient (70amps). I would put in a fuse between alternator & battery, i fried an Astra alternator (80-90amp) with a pair of DLS CAD1000s so you're close to the knuckle.

the WIDER the cable the less resistance (higher current/amp handling)
the LONGER the cable the resistance increases (in a car i wouldn't take this into consideration...cheap electrical 2.5mm cable over 100 Metres only as a resistance of 0.5ohms, so chunky car cable around 3-5 metres i wouldn't think about it)

The only reason i'm using 0 guage is my main amp uses around 800-1000 amps fully cranked

ah thats helped out a bomb, not going to consider wasting my money on 0gauge then if i dont need it i need it for my amp and sub but thats it.

i would of loved to of seen if the 0gauge wire would of made a diffrence tho...... what fuse do you reccon is needed?

my amp rms is 1200

i really don't think you'd see (or hear) any difference in your set-up going to 0 guage, but at the end of the day it's up to you & your money! (don't forget 0 guage accessories etc as well)

when i work out a fuse rating on powerful amps (1000+w) i use a 10v rule (as the current rises...voltage drops, your voltage shouldn't drop this low, but it allows some headroom for 'peak' in the equation) so i would use 1200w divide by 10v = 120amp. you can go conservative and safe with a 100amp fuse, or if your music has some serious bass kicks and you intend to use it! go with a 150amp fuse to allow for peaks.

if your alternator is rated 70amp, put a resettable fuse of this value between battery & alternator. better than driving some distance and then cutting out in some random place with a fried alt, then having to wait for Mr AA to come (i am speaking from experience )