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TR6 110A Alternator

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Ripper01

Ripper01

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My first post for help. I recently purchased a 110A alternator for my TR-6. This is a huge increase over the current Lucas alternator installed. I have seen the posting on the physical alterations possibly needed but do I need to make a major change to the wiring? If so are there any references?
On the VTR forum there was a link that looked promising but ended in a 404 error message- not availible.
Thank you all,
Rip
 
What year ? Is there an Ammeter or Voltmeter in your dash instrument cluster ?
 
I'd say it also depends on what you plan to do with all that current. But in general, yeah, you're gonna need some wiring improvements. The existing charge path (alternator back to battery) is somewhere around 12 AWG; you're gonna need more like 4 AWG.

Early car with an ammeter; probably the easiest way is to lose the ammeter and convert to a voltmeter. Otherwise you'll have to run new heavy wires to and from the ammeter, plus rig some kind of shunt so only a calibrated fraction of the current actually goes through the meter.

Without the ammeter, you can just run a new heavy wire from the alternator to the starter solenoid (to join with the cable from the battery).
 
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Two questions:

What mods to the car require a 110 amp alternator?

Serious upgrades to the wiring will be needed. Are you sure it is worth it?

Ed
 
I have a 1975 with a voltmeter. A 90 plus amp was recommended to me but does seem pretty big for what I need. Definately want to replace the Lucas alternator with a bigger one. I can still return it for an exchange.
 
The last 18ACR I bought was rated at 60 amps. I think the originals were only around 45.

Ed
 
Unless you have some specific need for high current, like a high-power audio system, a 55-amp alternator should be more than adequate. That would power all the usual stuff, plus modern upgrades, like driving lights, electronic ignition, a decent radio, and so on. If you do need something on the order of 100A, you are using about the same current as a starter, so wiring has to be sized like a starter, and connections must have large contact area and be bolted together good and tight. It's not a trivial undertaking.

If you don't mind telling us what you're doing, which needs high current, maybe we can make some suggestions.
 
Good points. I was recommended to replace my alternator with a 100 amp one but the more I researched it, the more work it would be. In fact I just replaced my headlights with LEDs so the draw is even lower now. Will replace the Lucas with a lower amp Bosch or Delco. I want the built in voltage regulator functionality.

I had purchased the high power alt on Amazon and returned it, no problem.
Thank you all for the inputs.
 
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