High Amp Alternator Upgrade

[bubbatrucklover]

I need a little guidance please. I'm replacing my alternator with a high amp one(same price online as a factory one locally so it was a no brainer and planning ahead ). It is a 200 amp 100 amp idle:

http://www.motorcityreman.com/99sigmcsi445.html

As I am upgrading the amps I need to uprade the wire. They suggest 2 AWG. I plan on a new battery as well(not really as relevant just saying) I will be getting rid of the factory fusable link in pic:

and going with a fuse block.

I will be going 2 AWG from alt to battery (via said fuse block) and 4 gauge( I have PLENTY "pretty red" from another project) from battery to starter. What size fuse should I use between alt and battery(225-250?) and what between battery and starter?

Thanks for the input.

 

[Zembonez]

Excellent upgrade but I have no clue on your fuses... so here's a free bump. Hopefully somebody here will chime in.

What amperage is the fusible link?

 

[bubbatrucklover]

Thanks.

I WAS going big three and going with an Optima then I felt some minor noise under the hood was caused by the brushes of the alternator starting to go so I figured alt first and battery next.

Good question on the fusable link amperage I'll try to find a rating. I know the fuse between alt and battery has to be upgraded in amperage(seemed I read in a post a while back it was suggested to be either 225 or 250) I know Bernie B. put a breaker on his ( I believe he has a 150 amp breaker for a 140 amp alt)but the fuse replacing between battery and starter can remain the same as the link rating. I would think.

Good call oh wise clown on checking the fusable link rating.

 

[bubbatrucklover]

Ok, no visable rating on link(or I'm just stupid) I'm sure it would coincide with the 105 Amp alt. and to be honest I've never put a fuse between a battery and a starter. I thought the link was alt only. ,but I have never seen this configuration before soooooo........

HOWEVER I don't want to be that guyand ASSume wrong and regret my decision.

 

[Bernie]

If the alt is rated 200 amps then a 225-250 amp fuse from battery to alternator will do the job. I'd lean more towards 225 amps though, just to be safe. As for the battery to starter connection, those generally aren't fused but if you really wanted to cover all the bases then you can put one in there. Should be between 60-90 amps of draw so putting a 100 will work.

 

[bubbatrucklover]

Thanks Bernie. I was going to PM you knowing you have quite the knowledge in this area,but I figured others(as well as myself) could benefit from you sharing.

This is the fuse I was looking at that was suggested by a local shop(appropriate holder too of course) comes in 250.

http://stores.channeladvisor.com/caraudiogiants/items/item.aspx?itemid=3530488

 

[Bernie]

Thanks Bernie. I was going to PM you knowing you have quite the knowledge in this area,but I figured others(as well as myself) could benefit from you sharing.

This is the fuse I was looking at that was suggested by a local shop(appropriate holder too of course) comes in 250.

http://stores.channeladvisor.com/caraudiogiants/items/item.aspx?itemid=3530488

It should work fine. The reason I was leaning more towards a 225 amp fuse is that it offers better protection for the alternator, but at the cost of possibly blowing under surge loads. To me, I'd rather change a $10 fuse than a $250 alternator.

The 250 should do okay though. It'll allow brief surges over 200 amps without blowing, but will still protect the alternator from dead shorts. The grey area comes with sustained high amp loads... If, for example, you routinely draw more than 200 amps, but less than 250, then the fuse isn't gonna blow but the alternator probably will have a very short life.

My ideal solution would be to use a 200 amp breaker instead of a fuse. Sure, it might trip at sudden high amp surges, but it's simple to reset and you don't have to try and find a replacement fuse in the middle of the night on a holiday, and if it's tripping often enough to become annoying then you'd probably want to look at a higher capacity system anyway.

 

[Z71 Kris]

what bernie said fo-sho

 

[bubbatrucklover]

It should work fine. The reason I was leaning more towards a 225 amp fuse is that it offers better protection for the alternator, but at the cost of possibly blowing under surge loads. To me, I'd rather change a $10 fuse than a $250 alternator.

The 250 should do okay though. It'll allow brief surges over 200 amps without blowing, but will still protect the alternator from dead shorts. The grey area comes with sustained high amp loads... If, for example, you routinely draw more than 200 amps, but less than 250, then the fuse isn't gonna blow but the alternator probably will have a very short life.

My ideal solution would be to use a 200 amp breaker instead of a fuse. Sure, it might trip at sudden high amp surges, but it's simple to reset and you don't have to try and find a replacement fuse in the middle of the night on a holiday, and if it's tripping often enough to become annoying then you'd probably want to look at a higher capacity system anyway.

I like the breaker idea better. I had one in another vehicle and liked the reset factor over the replace factor. I don't know if I'll ever get to the point of pushing a 200 amp draw so the alt breaker and battery combo will HOPEFULLY suffice for quite some time.

Thanks again for the knowledgeable input.

 

[bubbatrucklover]

what bernie said fo-sho

You know it. It's always good to heed the advice of someone who knows his shiz.