subwoofer cancellation

[superfishbone 1]

im planning to build 4 15" RE SRX on a toyota 1983 corolla DX.. the car is very small, and for me to fit them is to build a wall..

the car was used for racing and is in pretty bad shape.. so what i did to make fit the 4 15" was to make a new flat form for the boxes to stand on..

a new rear wall to have a flat surface..

now im building the box for the 4 15s..

the problem is.

the car its self is pretty small.. and for me to build an independent box for the each 15 and go ported i need a bigger space but it seems i can only get 1.8 cubic ft. for each 15s. so i plan to go sealed on the 15s 2 subs in one common chamber..

what would cause these subwoofers to have cancellation?

should i just go flat surface with all four subs facing front.

or

build a common chamber sealed box in a vshape box for 2.. the upper sub facing angled down, and the lower sub facing angled up equally.. some goes for the other 2 subwoofers.. or would this design cause cancellation?

[KU40 173]

Neither of those will cause cancellation.

[Impious 1,476]

Cancellation in the subbass isn't really a problem in an automobile, the dimensions are too small. Basically as long as you have all of the subs pressurizing the cabin at the same time, you're good.