Quick question for the m20b25 guys…..
What route did you take the battery cable from the boot to the starter?
Through the interior with the loom and out through the fire wall? Same hole as the cable for the ecu?
Or is underneath a better option?
M20b25 battery cable
- BertjeConti
- E21 Mad
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Re: M20b25 battery cable
Never route battery cable's underneath, thats a dangerous option.

Megasquirted '77 E12 520-6
Aspen Silver '96 E39 523i
- nic65
- Upcoming E21 fanatic
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Re: M20b25 battery cable
in the e30 it goes inside, in my e21 I put the battery in the back. I made a hole and it goes inside too
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Re: M20b25 battery cable
Nic65, I have the battery in the boot also. Did you take the battery cable into the engine bay with the loom or make a new hole?
You can't polish a turd.... but you can roll it in glitter!!!!
- nic65
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Re: M20b25 battery cable
I rebuilt everything new, the cable that from the starter motor enters the car with a hole on the passenger side (behind the glove compartment) and goes to the trunk, I also recovered the front battery support and put it in the trunk too
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Re: M20b25 battery cable
Awesome thank you, yeah I’ve re used the original battery tray too.
Did you make another hole for the cable to the ecu?
Did you make another hole for the cable to the ecu?
You can't polish a turd.... but you can roll it in glitter!!!!
- nic65
- Upcoming E21 fanatic
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Re: M20b25 battery cable
no need, mine has a 2000 M10... with carburetors 
