Mazda 3 Trunk Build 153.9 dB 2 DC XL15's

[BassHead810]

What were your score with the 10" port?

I'm getting there, I built a whole new box after I maxed this one out. I will show the build of that box. I still gotta post new Alt new Battery big 3 upgrade and some other mods to this box first.

[cjvue]

What were your score with the 10" port?

I'm getting there, I built a whole new box after I maxed this one out. I will show the build of that box. I still gotta post new Alt new Battery big 3 upgrade and some other mods to this box first.

Don't be holding out on the pic now ... Weren't you at wf?

[SCS_Audio]

What were your score with the 10" port?

I'm getting there, I built a whole new box after I maxed this one out. I will show the build of that box. I still gotta post new Alt new Battery big 3 upgrade and some other mods to this box first.

Don't be holding out on the pic now ... Weren't you at wf?

Haha! He is going in chronological order. You will have to wait till the last chapter to see!!!

[Fi-Foo]

damn good shit man. I got a 2011 3 with a single 15 AA Mayhem. and soon to be Fi Sp4 in the next week or so. Thats insane hairtrick for 2 12s. How did you do that lol?

[SCS_Audio]

damn good shit man. I got a 2011 3 with a single 15 AA Mayhem. and soon to be Fi Sp4 in the next week or so. Thats insane hairtrick for 2 12s. How did you do that lol?

You will have to let us know how you like that SP4!!! I was just looking at those the other day. Want to do 2 of them in a trunk with about 5000 watts and see if we can do a 155 out of a trunk!!! They look very good for the price. What makes you want to switch from the AA to the SP4?

[Fi-Foo]

damn good shit man. I got a 2011 3 with a single 15 AA Mayhem. and soon to be Fi Sp4 in the next week or so. Thats insane hairtrick for 2 12s. How did you do that lol?

You will have to let us know how you like that SP4!!! I was just looking at those the other day. Want to do 2 of them in a trunk with about 5000 watts and see if we can do a 155 out of a trunk!!! They look very good for the price. What makes you want to switch from the AA to the SP4?

Since im running the Saz 3500 i want something that can take the power better. And i want the space spider option to keep the coil from rocking.

My brother has a wall with 2 sp4 15s and it got ouder then when he had 2 mayhems so im gonna try it out.

[BassHead810]

A few mods to these boxes.

1) Upgrade speaker wire from crappy 18 gauge to 8 gauge.

2) Router inside of subhole

3) Line inside of box with smooth material in lieu of resin.

4) Put pvc rounds in 2 corners of each box.

Total gain = .4 dB and from looking at my clamped numbers I think most of it was from the speaker wire upgrade.

Pic from inside the box looking out showing the material. I don't even know what the real name for it is, it was scrap material that I got from work. Its about 1/16" thick and fairly flexible, one side is glossy and one side is matte. Its sometimes used as notebook covers.

New termlab score 147.5 @ 51hz sealed on dash

Event results from the last show I went to with stock electrical. I put up a respectable score for the Street Stock class at that time. Lost to a CRX

http://www.termpro.c...451&Method=1001

[baaudio]

Great build man. Really impressive results, I am really pulling for you to get that 150!

[BassHead810]

So at this point I knew I needed to upgrade the electrical ASAP. I may have been able to hit a 147.5 on a burp but my voltage drop was ridiculous with those regulated JL amps. I saw it go below 9v a few times.

The plans for the upgrade:

1) Replace oem 90A alt with Mechman 250A Idle Max unit

2) Install external voltage regulator for new mechman alt

3) Replace oem battery with XS D3100

4) Big 3 upgrade

I ordered a Mechman 250 amp "Idle Max" alt thanks to Matt from Mechman. This unit can do 200 amps at idle on my vehicle and full output by 1800rpm. I also got the external voltage regulator because I wanted control over the charging voltage. I was tired of seeing my voltage sit at 13.4 or lower on the hot summer days at competitions.

Since I'm competing in Street Stock I could only have one battery so I replaced the oem battery with a XS D3100.

This thing just barely fit. There was a spot on my engine block that sticks out about half an inch and was just barely touching the alt. So I spaced the alt out from the frame with a couple washers on each bolt.

Since the alternator sits so close to the exhaust of my engine, Mazda had a heat shield mounted to the engine side of the oem alternator. The heat shield didn't fit around the Mechman alt however. But I knew it gets really hot down there so I did what I could to get it mounted with the Mechman alt. Ends up I had to modify the bracket that holds the heatshield in place and I was able to get it to fit. I had access to some Heatshield from SecondSkin which I added to the existing shield.

Its not perfect but its better than nothing.

[BassHead810]

Time to get that big honkin battery in there somehow lol. The Battery location on my vehicle is tucked clear in the back of the engine compartment so I wasn't able to simply drop it in from above. Ends up I had to take the air filter out to get a straight path in.

We applied SecondSkin Heat insulation to the battery as well since its going under the hood.

I have access to a milling machine at work so I ordered some aluminum bar stock from Grainger and started doin work on some upgraded terminals. I put 4 1/0 on each side for more flexibility if I run more wire in the future. I also put some set screws and some hex bolts so I could fasten wires with ring terminals too. The bolts also make a nice place for the charger to clamp to.

So now the big question is... How much did all of the electrical upgrades help???

Well, first I will say that when driving down the road my voltage only drops .2-.3 volts at full volume. Much better than the 2-3 volts drop from before lol.

Now how about some termlab numbers.....

I gained almost a whole dB!

And I don't even need to rev anymore