Couple wiring questions

[AutoMods]

I'm installing a battery disconnect and cleaning up some wiring under the hood.

two questions
1. Is it ok to use the starter main power bolt as a power distribution. I'd like to have the main 12v wire there, alternator terminal and a terminal to an 80 amp fuse panel hooked there.


2. Is it ok to have a main 200 amp fuse coming right out of the battery. I know a lot of factory wiring goes straight from battery to starter with no fuse. Can the fuse cause any voltage drop or current issues? Its possible I'm using up to 180 amps during cranking so its somewhat close to the fuse rating.

[86svo9L]

Are you getting rid of the factory under hood fuse box?


I would set up a distribution block and hook up powers to that.

Maybe someone else could chime in, not sure if the draw from the starter would have an affect on any electronics attached to it.

[sparkles]

Yes and yes.

[sLoWnStEaDy]

GM did that for years from the factory, I don't see how it could hurt anything. I personally don't like all those "hot wires" down there were I can't see them or access them easily. I doubt you're car ever see's much rain/muck but I didn't like the idea of them all being down in that junk either. you CAN do it though...

Also, 180A seems like an awful lot of current draw for a starter...? I've only checked this a handful of times (for the same reason) and the most I've seen was like 120A and that was on older 460 BBF with 10.8:1 compression. I'd assume the lower the compression, the lower the stress on the starter so it wouldn't draw as much current. If you want an expert opinion, call Beusings Iowa Generator (319) 363-0271. They've helped me a lot over the years when it come to starters and alternators!!

[Larsons Fox]

You should be good Ryan. My relocation is all on one bolt. Not sure why you would need a fuse but that one should be plenty.

[AutoMods]

thanks guys. i have a 2 gauge 12v wire coming from the rear license plate battery disconnect switch all the way to the engine bay. some of the wire is under the carpet, then some runs under the chassis, i just feel safer with a fuse if the insulation wears off that wire or an accident grounds it.

[sLoWnStEaDy]

A fuse/breaker is ALWAYS a good idea IMO... I relocated my Fiero battery up front and I have a 200A fuse like 6" from the battery. Running 2ga, I assume you went with a good OFC wire? Just asking because a lot of local places sell "2awg" CCA that is really closer to 4awg and therefore can only handle like 125~ amps.

[Phish]

I have mine ran off the starter wire as well. The wire goes up to the starter and fromthere i jump off and run the power to the fuse box under the hood on the driver side. I have not had an issue with it.

As far as a fuse in the main power wire goes, i have none. I was told that the starter woudl cause to much draw and the fuse woudl be so large for the starter to function properly that if there was actually an issue, the fuse woudl be to large to blow anyway. Not sure what truth there is to this, but if you figure out a good fuse and or breaker to use for this, let me know and i will add one in.

[sLoWnStEaDy]

Not true from my experience and this is one thing I have QUIIITE a bit of experience with. I've never seen a 150-250 amp fuse blow from normal usage. I have see a power wire rub amd ground in a frame which popped it, obviously. That's why its a good idea, IMO

Ask me why I relocated my Fiero battery and spent 3 hours redoing a handful of wiring. :-/ it would have been MUCH easier to just replace a fuse... I was using OFC 4awg, rubbed through some where, grounded out, melted my battery terminals and a bunch of ither smaller wires and fusible links.

[Sleepy]

Granted my battery is under my front bumper, but my power goes from battery to alt, then alt to starter and another line is run to the fuse box. I have not had any issues.

[AutoMods]

i had a 150amp fuse that was fine for many years. it recently blew and I noticed the ground wire at the battery was warm. but I've been having some random slow start or no start issues (just clicks) so that probably had something to do with the fuse popping. has been happening with my old and new engine and two different starters. i'm cleaning up the grounds and improving some wiring now.

this is not my car but found this guy drawing 180 amps

http://www.youtube.com/watch?v=PO73iHVj1Po
http://www.youtube.com/watch?v=PO73iHVj1Po

[slow ride]

Trust me a starter can draw a lot more than 200A when the conditions are right. It's really cold temps that push the amperage up though or the higher compression, etc. I've seen stuff draw over 600A but thats larger diesel engines in sub zero conditions.

[sparkles]

That's why you get a slow blow fuse

[sLoWnStEaDy]

I know under "certain conditions" they can pull a ton of amperage. I was thinking specifically of Ryans car though. Figure it doesn't really see cold temps and has low compression so I wasn't figuring it would draw much in his setup. Either way though, looks like you gotnthe answers yiu were lookin for.

[rb69]

check out http://madelectrical.com

He has some interesting ways of powering cars that transfers to what sounds like you are wanting to do