Anybody know the location of the bolts under the hood in order to do the big 3 upgrade? I know lexus isn' exactly easy to work with when it comes to electrical.

 

The locations are universal on all vehicles.

You'll pick a bolt that leads off of the battery, and the other end to the alternator.

You'll pick a bolt that leads between the engine's ground and the chassis (note, this is different on every engine. You didn't specify which vehicle you have). The location for MY car is on the passenger side of the engine bay. It's around the ports for the spark plugs.

Your last location would be the battery ground to the chassis, you'll parallel the wires here also (just like the battery to alternator).

 

As a side note, I wouldn't do Big 3 if you're running stock alternator. Juice will only increase if you get a bigger alternator in ADDITION to Big 3.

btw what amp and subs are you running?

 

Believe it or not, with the dinky wiring system we have. It would help more than you think.

I've done all 1/0 runs for my big 3 upgrade. It's not like OMG SO MUCH POWER, but it helps somewhat distribute and lessen the load on the OEM wiring. (I believe OEM wiring is only like 4 or 6ga... either or it's not very beefy).

I have a system containing:
-2 Viair 400c
-1 CT Sounds at1400.1 amplifier (running at 0.5ohm, ~2.8kw RMS)
-1 JL Audio G6600

I have other stuff in the car too, but they draw so little power I don't think it matters to post it up.

 

Doesn't help as much as I think. With generating same output from stock alternator, unless your lights dim when bass drops, it won't do much. It is helpful, but insignificantly without a HO alternator. Only maybe battery to chassis upgrade would be good since you ground the amp to chassis most of the time anyway.

So keeping good condition stock ground by upgrading would be good.
Big 3 will minimally help without a HO alternator, but will help more if your lights dim.
OEM wiring is properly sized (plus a bit more) for stock alternator because if it wasn't it'd be a fire hazard anyway.

I know this from friends that are car audio tech's, and you can easily google big 3 with stock alt.

 

I dont disagree with you. I didn't have light dimming issues (you shouldn't to be honest, our cars use LEDs for the majority of the car).

Like you said though, big 3 helps MINIMALLY with our cars. It just does not provide the proper amperage for my needs, but it helps a little tiny bit.

You have to note, when they made the wiring specs for our cars, they specified it for OEM applications, that is, using all OEM components. They never considered that we would be modifying our cars to take draw more current than the OEM desired.

Also, you have to factor in that wires don't last forever. All wires degrade over time, so beefing it up does helps a bit for some (especially if you've put a lot of driving/usage time on those wires).

In my case, it helped up to a certain extent, people that believe these big 3 upgrades are dreaming, because exactly like you said, it just helps the flow of electrons go by easier, the smaller the wires, the more resistance there is when you're trying to send electrons through it.

Just as you would compare to yourself being in highway traffic, more open roads, more smoother transitions on the road from point A to point B.

Like you've said, googling big 3 on OEM alts, there are mixed reviews and a lot of FAKE claims about it making systems A LOT better than before (especially if you cruise around youtube).

I've been doing car audio as a hobby since 2004, it has been 14 years now, I've been studying electronics for 3 years now, as an engineer, so I completely understand where you're coming from, but you can't deny it will at least aid in lightening up the load off your OEM system.

Anyways, we're getting a bit off topic now, OP said he wanted to know locations to do Big 3 Upgrades, and he's gotten his answer

 

Yup, can't deny it, lol. At least this thread is pretty educational now. Fun discussion