Question on drilling the floorpan for sub and amp mounts

[Coblue]

I want to mount a sub and/or an amp under my seats in my '75, but I'm wondering if drilling through the floorpan is a good idea. Is there an alternative? Do you use any sealant or anything on the screws ?

[blucille]

I'd rather use an adhesive or maybe velcro to hold a thick piece (1/2") of ABS (plywood is ok, I suppose)....and then short screws into that instead. I'd rather not penetrate the floor unnecessarily

[john walker's workshop]

Hurt myself plenty of times on screws sticking out of the bellypan. At least cut them off flush.

[Locker537]

I would not drill holes in the floor for audio gear. Not because there is anything wrong with it, but because it's not necessary. I'd fashion some mounts to the seat or something else.

I have drilled holes for harness sub straps. I use silicon RTV to seal the reinforcement plates to the floor on the exterior.

[Tony V]

Velcroed my powered sub to the floor mat under the passenger seat in my ‘74. Left enough wire slack to be able to pull the whole thing out without having to remove the seat. Hasn’t moved during AX or track time.
Tony

[X JBM X]

velcro'd my sub to the floor under the passenger seat in my '84. for the amp, check out the Alpine KTP-445U - i just installed this and tucked it under the passenger front floor board.

[rwest]

I just did this with the ECU for my EFI install and I made a mounting bracket out of aluminum to screw the ECU to and then used rivets with sealant to affix it to the floor pan- I will seal/paint the underside next time I crawl under the car.

[cabmandone]

I poked 4 holes in the floor under the passenger seat to mount my powered sub. the heads face down to the ground and I put some silicone on them when everything was tightened. I installed the Cerwin Vega 10" under seat sub and it sounds REALLY good.

[1979-930]

Don't drill the pan.
Just silicone or adhesive glue a thin piece of MDF or Plywood to the floor and screw to that. You don't need a lot of holding power for theses items.
The Velcro to the carpet would probably be fine for a small light amp.

[Coblue]

I like the velcro idea. I think I can sew it to the carpet and go that route. My passenger floorboard panel is ABS plastic, and the amp I have ( Rockford Fosgate P400x4) has been known to run warm so I'm wondering if it'll melt the ABS, but there's room under the seats for both the amp and the sub (Alpine PWE-S8) so there they are. I hated the thought of drilling and like John Walker, I've seen what bare screw ends can do to a scalp, so I'm happy I asked. Thanks!