Sub Help: Who’s Cut Their Hump?

[h2ohangtime 4]

After exhaustive search here and on WW among others, I still haven’t found a clear answer as to whether or not I can cut out the molded-in footwear under the helm of my ‘07 Typhoon C4. I’m trying to build a system with 4 JL MX650’s, a ported JL 10W3, and a JL M1000/5 or Alpine PDXv9.  Problem is that I can’t find a good way to install the box without getting rid of that footrest/hump under the helm.  Is it structural?  Just cosmetic/meant for a factory IB sub only?  Has anyone cut it out and had good results?  Any pics?

[Wylie_Tunes 146]

Cut away

[h2ohangtime 4]

Foot REST, but I think you got it.  Thanks!

[h2ohangtime 4]

Anyone have pics of this project on an Avy/Typhoon?  Is it as simple as cutting along the planes of the floor and starboard hull, re-glassing with several layers of mat and resin, then re-carpeting?

[cjohnson 33]

I did this in my old 05 Avy but can't find the pics.  I cut out the face and top of the footrest then built a ported box that followed the angle along the front.  I re-glued the existing carpeting and cut out holes for the sub and port. If you have the ability to build a box definitely do it.

[bomoseen avy 45]

[bomoseen avy 45]

Did this a few years back on my '03 Avy. I had a heater port and a sub in the footrest. Sawzall around the perimeter. Used styrofoam between the back part of the hump and the steering cables and other junk that was hanging out back there so I didn't cut anything. 

Built a "bridge" over the hole in the floor with birch that was elevated using some plastic washers so air would flow in there and keep from collecting moisture. Coated the birch in fiberglass resin and think I plastic-dipped in black. Then mounted box with new JL sub onto the "bridge."

Later built a section next to it to hold the heater vent. Was very please with the results

Edited October 16, 2018 by bomoseen avy
grammar

[bomoseen avy 45]

Sorry couldn't find any pics of finished product!

[h2ohangtime 4]

4 hours ago, bomoseen avy said:

Thanks! Anything that would preclude one from just filling the void with foam, trimming it flush, and then re-glassing with several layers of mat?

[bomoseen avy 45]

not my field of expertise. My project was with input from other crew and box/subwoofer support worked flawlessly.

Good luck!

[Wylie_Tunes 146]

I see no reason why you could not close the hole up in a permanent fashion. There is nothing in that void of the bilge that is serviceable. On the flip side, once the enclosure and facade are in place, you will never no it one way or the other. So nothing wrong with leaving the cut out as is.  

[h2ohangtime 4]

2 hours ago, Wylie_Tunes said:

I see no reason why you could not close the hole up in a permanent fashion. There is nothing in that void of the bilge that is serviceable. On the flip side, once the enclosure and facade are in place, you will never no it one way or the other. So nothing wrong with leaving the cut out as is.  

That makes sense to me.  Probably best to go with the open way first and then close it up if that doesn't work out.  Thank you!

[Troy 234]

Did you ever finish this project? I’m getting ready to cut mine this year. Love to see some finished pictures!

[Troy 234]

I cut mine this past weekend. 2008 Avy. 
 

[bomoseen avy 45]

Nicely done!!! Ahhh, brings back memories ?

[jtryon 24]

for anyone who's done this cut, is the area under the footwell an area that gets water/moisture from the bilge area during normal boat use?  i'm thinking of doing a free-air sub there but don't want it to get destroyed if that area gets damp at all.

[Wylie_Tunes 146]

Use a quality, well built marine woofer and its a none issue. If standing water rose to that level, your boat is going down. 

[jtryon 24]

thanks @Wylie_Tunes.  i want to free up some storage space because i have 2x12's in a ported box taking up most of the space under the passenger seating area; will my bass go to crap by going to a single free-air 12 or 15" (if it fit) in that location?  i'm definitely not looking to win contests, just have respectable sound.

[Wylie_Tunes 146]

Heres the deal, its mostly about surface area. Two 12's in a ported enclosure is nearly 4X the surface area as a single 12 in a sealer or free-air (infinite-baffle) setup. So you would definitely experience a reduction in overall bass output.