Has anyone been able to get a 15" sub into the boot of a
Coupe ? I'm thinking I want more bass and seen a nice 15 in my pricerange

Shouldn't be a problem, it will probably need to be mounted at an angle though. I have a 12 and there is only a couple of inches top and bottom once it's all boxed up.

I have two 12's in my boot at the mo , but they just don't go low enough that's why I want a kicker solobaric 15" just need it to fit

I have an old skool kixker xpl, the box volume sealed was 2 cu ft and that was known as a sub that could run in small enclosures

A set of 12s however in a nicely ported box should drop low enough, is your box tuned?

noits just a generic box for a pair of 12" square subs... do you think it would make that much difference if it was a custom box?

You could always fit those in a band pass box if it's low you want.

It would probably shake the car to bits!

make a sub build of your own outta wood or fibre glass you can then define the dimensions the required volume of the unit according to the size of the sub