just for competitions

Just for sh**s and giggles i was thinking about putting 8-10in Crossfire BMF-1028 subs in my Expedition for USAC comps. I am looking for some input here on how to go about it with design. Does not have to be a daily box. Was looking at running about .75-.85 per sub ported. Truck itself peaks right around 40hz. I came up with a enclosure about 5.90 cuft with 4-4" round ports @ 10.09" long(thats right around 42hz). What are your guys thoughts on something like this ? just looking for some input. By the way the vehicle is a daily driven 04 Ford Expedition so I need the box to come out when not doing competitions. This set-up will be ran off 1 Crossfire BMF-1700d. Thank you all for your input.

According to CF's website, those subs can handle 500wRMS each, which sounds about right for a 2.5" voice coil. That's 4000wRMS to drive them fully.

If you've got 1750 @ 1 ohm on deck... you need to decide what's more important: SPL or moving air. 8 underpowered subs will move plenty of air, but "probably" won't yield the SPL results you'd want.

If it were me, I'd do 4 of the 2 dual ohm BMF's wired to 1 ohm, in a box with 4 cf internal volume. Subs up port back, with a big slot port (60 sq in area and 10.5" long for 43 Hz). Keep the box 4 to 6" from the rear door, and play Lil Jon - Push That in SB3. It should yield a decent score, and it's not too huge just to leave in there for daily... unless you need 3rd row seating.

I'm envisioning this, with 4 10s instead of 2 15s:

i think your idea sounds fine. but with that much cone in that box whatever that computer program is telling you goes out the window.. i think its going to be a bit higher than 42hz. but id build it and see what happens..

Ive decided to not worry about what to put in my Ford Expedition and just buy the 87 CRX across the street from me for $850.00 and it runs...thank you everyone for your input. Ill need more for the CRX

Good call! The build a crx wanab when there is the real thing?

Its difficult to get loud in the expedition when it is my daily vehicle for everything from grocery shopping to haulin my 28ft travel trailer, so its not like i can tear it up for audio. Ive been looking for a car for months to build a system in and a CRX just happen to pop up for a good price...

chrisfish wrote:

Good call! The build a crx wanab when there is the real thing?

Some of us enjoy being CRX wannabe's

You'll be much happier competing with a rex, excellent platform, and $850 is a good deal, if it still runs.

put all those 10s in the crx!

Its funny, I talk to Crossfire about doing 8-10's in the Crx and he said it just might be to much and I will actually loose spl...

id use 6 two facing up two to the drives side and 2 facing foward aero ports out the back

StreetbeatExpedition wrote:

Ive decided to not worry about what to put in my Ford Expedition and just buy the 87 CRX across the street from me for $850.00 and it runs...thank you everyone for your input. Ill need more for the CRX

87 crx is hard to get loud. 88-91 not so much.

a friend of mine did six l5 10s in a rex on one 2500 kx and put up a 153.3 took it to only one comp and sold it ... it was a frikin loud car ...dont know anything a bout the box size or tuning, but there was a lot of dynamat and six runs of 0 gauge.for the subs it was 2 up and 2 on each side ports back if i remember right