Audio Amp Installation

[mrputler]

I'm getting ready to install a mono amp for a sub in my '01 Forester,
but I'm not sure how to route the power from the battery to the amp
which will be installed under one of the front seats. I would like to
hear from anyone who has done this type of install, and would like to
know where in the firewall you routed the power cable? Is it possible
to go through an existing hole, or did you have to create a new one?
Is there another option besides going through the fire wall? Any
suggestions are appreciated. The wire size recommended by the amp
manufacture is 8 gauge.

Thanks,
Mike

 

[Hachiroku $B%O%A%m%/(B]

I'm getting ready to install a mono amp for a sub in my '01 Forester, but
I'm not sure how to route the power from the battery to the amp which will
be installed under one of the front seats. I would like to hear from
anyone who has done this type of install, and would like to know where in
the firewall you routed the power cable? Is it possible to go through an
existing hole, or did you have to create a new one? Is there another
option besides going through the fire wall? Any suggestions are
appreciated. The wire size recommended by the amp manufacture is 8 gauge.

Thanks,
Mike

Common wisdom says *NEVER* bore a new hole in the firewall! I have been
told it can make a 'rip' point if the car is in an accident.

Look for an unused rubber plug or pass-through, or find an existing one,
and either poke a hole in the plug to pass the wire (being *REAL CAREFUL*
not to damage any other wires in the bundle!!!) or heavily insulate the
new wire at the point where it will pass through the fiewall and 'bypass'
the plug by shoving the wire into the hole.

If you're *REALLY* paranoid about water, etc, get some black RTV, pass the
wire, and goop it where the wire goes through. The rubber they use is sort
of 'self-closing', so if you do poke a hole I don't think you'll have any
problems.

Done this about a dozen times...works for me!

Now, in the good old days, Toyota used to make all the firewalls the same,
so if you had an Automatic, there was still a hole with a plug in the FW
for the clutch cylinder. My Supra has this, but a '95 Tercel I had didn't.
Look to see (if you have an A/T) if there is a plug near the brake master
cylinder. If you do, it's a snap!

 

[David]

Common wisdom says *NEVER* bore a new hole in the firewall! I have been
told it can make a 'rip' point if the car is in an accident.

Look for an unused rubber plug or pass-through, or find an existing one,
and either poke a hole in the plug to pass the wire (being *REAL CAREFUL*
not to damage any other wires in the bundle!!!) or heavily insulate the
new wire at the point where it will pass through the fiewall and 'bypass'
the plug by shoving the wire into the hole.

If you're *REALLY* paranoid about water, etc, get some black RTV, pass the
wire, and goop it where the wire goes through. The rubber they use is sort
of 'self-closing', so if you do poke a hole I don't think you'll have any
problems.

Done this about a dozen times...works for me!

Now, in the good old days, Toyota used to make all the firewalls the same,
so if you had an Automatic, there was still a hole with a plug in the FW
for the clutch cylinder. My Supra has this, but a '95 Tercel I had didn't.
Look to see (if you have an A/T) if there is a plug near the brake master
cylinder. If you do, it's a snap!

Use a suitable fuse at the battery end of your # 8 wire.

 

[Hachiroku $B%O%A%m%/(B]

Use a suitable fuse at the battery end of your # 8 wire.

I do, but modern amps have their own fuses as well. But it's still a good
idea, especially if there is ANY chance the insulation may break down and
the wiring touches bare metal!!!

 

[nobody >]

I do, but modern amps have their own fuses as well. But it's still a good
idea, especially if there is ANY chance the insulation may break down and
the wiring touches bare metal!!!

With #8 wire, a 30A fuse is spec. Subs are known to blow "spec-size"
fuses once in a while. You can go up to a 40A if this happens, with the
amp fused itself all the batt-end fuse is doing is protecting the wire
if it does short to the body. If this happens, a 40 will blow just as
fast as a 30.

If you are using those 10-50 farad capacitors with your sub. you may
have to go to a 60A fuse. Them puppies do suck some serious juice when
charging up!

 

[nobody >]

nobody > wrote:

I misremembered the reason (and I do wire/fuses to the battery all the
time at work... ??) there's a fuse at the battery....

With #8 wire, a 30A fuse is spec. Subs are known to blow "spec-size"
fuses once in a while. You can go up to a 40A if this happens, with the
amp fused itself all the batt-end fuse is doing

IS PREVENTING UNDER-HOOD FIRES........

 

[Hachiroku $B%O%A%m%/(B]

IS PREVENTING UNDER-HOOD FIRES........

You mean, like AMC Eagles and Gremlins?

 

[mrputler]

If anyone wants to know...

I ended up using the hole the air-conditioning drip line goes
through. It's located on the passenger side, and I was able to get to
it from under the car. It's located about half way up the firewall,
and you will see a hose about 1/2 inch in diameter hanging down with
nothing connected to it. I was able to push the #8 wire between the
grommet and hose very easily.

 

[nobody >]

If anyone wants to know...

I ended up using the hole the air-conditioning drip line goes
through. It's located on the passenger side, and I was able to get to
it from under the car. It's located about half way up the firewall,
and you will see a hose about 1/2 inch in diameter hanging down with
nothing connected to it. I was able to push the #8 wire between the
grommet and hose very easily.

Thanks for the info!

I added to the subject line for better googability. This is something
that can be used by CB'ers, ham radio operators, and others needing a
way to poke that important wire .....

It can be an absolute pain to find these holes, been dere, dun dat.