How many amps to start these things?

[offalot]

I am relocating the battery and want to make sure I get a heavy enough gauge wire. I imagine between the high torque starter and the glow plugs being on, not to mention other things that could be on at the time, lights, blower motor, radio etc. it would be a decent amount.

[JHH]

Uh-oh... This might be a bad idea. Are you damn sure there's no working around the battery where it is? The problem isn't just the current capacity of the wire itself, but also voltage-drop, which is especially pronounced at low voltage and high current over long runs.

Somebody, possibly on another forum, was trying to get his Golf to start with the battery in the trunk for some reason. Far as I know, he never got it working.

So... Where are you thinking of moving the battery, and would you be prepared to spend a great deal of money on very large wire (think 0000# or more)?

(Sorry to seem gloomy - I just don't you to end up frustrated.)

[offalot]

Man I hope it's doable. I was just looking at charts that outlined the amperage drop over distance, as you were talking about and I had no idea what a difference it made. I have already mounted the battery behind the passenger seat in my truck, I think I can get away with a bit less than 10 ft. Right now I have 2awg wire.
Probably wouldn't be such an issue if this thing didn't see some ahrsh winters.

[JHH]

Behind the passenger seat might be okay, but I think you'll want larger wire.

You might luck out and find an old truck at a junkyard with what you need.

Good luck to ya, buddy.

[JHH]

If my memory was any worse, I could plan my own surprise-party. You might be okay after all.

viewtopic.php?f=8&t=10966

[offalot]

Seems like I'll be borderline huh? I guess I'll give it a shot. I wanted to get a cable from something at the junkyard but find it difficult to get up there with work,and I'm impatient. I'll run the 2 gauge as short as possible. I grounded to the chassis at the large seat belt bolt. I'm hoping this Is strong enough to not have to run a seperate ground cable.

[82vdub]

You can always run parallel wires (like parallel 2ga) if you get the connectors that will accept both cable terminations, or connect them as best you can.

[offalot]

You can always run parallel wires (like parallel 2ga) if you get the connectors that will accept both cable terminations, or connect them as best you can.

Yeah, I was thinking that. I'll have to see if u have enough wire.
Looks like the junkyards open on Friday so I may wait till then and just get a good beefy cable. I know even if the 2 awg works it will probably be less than ideal come winter.
I'll wait and see how the body ground stands up.

[JHH]

I might also recommend a ground-strap between the body-work and the starting motor itself... Just to be sure.

[offalot]

Not a bad idea. Would probably mae the connection a bit stronger. Well I will try to remember to post my results, but it will probably have to wait till this weekend, as I will try and hold out to get a nice big fat wire. I know BMW's, newer Buick's, Older Audi's have a rear mounted Battery. Might have to do a little hunting around to see if I can find anything else. Probably something that has to spin a big ol' V8 might have a healthy sized wire. I know with conductors, you can't really go too big.

[surfcam]

One way to gage your success with this project is if you can spin your engine over 750rpm. You can crank it all day at 600rpm and you will be just wasting your time. Your have at least get it to 750rpm before it will think about starting and don't ever walk by it with an ice cream cone. I know I know another tool and this Scotsman hasn't got around to buying one either. Even though they would be a great diagnostic tool but they are getting with in range price wise.

[offalot]

Wish I knew how to determine my Rpm's.
Also wish I had some ice cream.

[TylerDurden]

Mmmmmm..... ice cream.....

Personally, I think higher cranking rpm is more important when compression is low. If compression is good, the air in the cylinder gets to ignition temperature earlier and lights off the fuel easily.

Regarding cables, I've heard that welding cables are more flexible and therefore easier to run from remote locations to the engine bay.

Regarding cold weather & batteries, I've heard that some guys will keep floodies warm with insulation, some also use heaters.


But... Why move the battery?

[surfcam]

Ok OK the next time I come through Michigan I'll bring ice cream. I agree with you on the low compression. I just sold a 91TD that would only start by towing it quite fast. It had really low compression. If I remember right this guy on another forum was saying the 750rpm was the minimum rpm for starting.

[offalot]

But... Why move the battery?

As we all know, these cars are not fast, but they can be quick. My truck is lowered and has wider tires and I love cornering in it. I have gotten a little addicted and am now seeing how well I can make it handle. I've made an upper strut bar, am going to make a lower bar and add a rear sway bar. The battery behind the seat will move a good chunk of weight from way ahead of the wheel to a nice lower mid point. Will it make a difference? Ehh maybe. But it makes me feel like a Johnny racer and that's all that matters.