Website for calculating sub box size

[TubsAlwaysWins]

Anyone know of a website or program that's free that will calculate the dimensions and stuff for a sub box? I wanna make a ported box for 2 18s I have but I dont have any info on them other than the size and ohms

 

Edit: I found the specs for the subs. They came out of a JBL MR818

[Stagea]

Download WinISD. It helps tremendously in modeling, as long as you have the T/S Parameters.

[spwath]

15 minutes ago, Stagea said:

Download WinISD. It helps tremendously in modeling, as long as you have the T/S Parameters.

Should be easy to find T/S for JBL's, their spec sheets are always online.

[TubsAlwaysWins]

1 hour ago, Stagea said:

Download WinISD. It helps tremendously in modeling, as long as you have the T/S Parameters.

Well I dont have those paramaters

 

1 hour ago, spwath said:

Should be easy to find T/S for JBL's, their spec sheets are always online.

This is the only thing I can find on them. http://www.jblproservice.com/pdf/MR800 Series/MR818.pdf

They arent made to be car subs or anything. They were made to be big stage speakers (Which I know but im using them as temporary car speakers)

[spwath]

2 minutes ago, TubsAlwaysWins said:

Well I dont have those paramaters

 

This is the only thing I can find on them. http://www.jblproservice.com/pdf/MR800 Series/MR818.pdf

They arent made to be car subs or anything. They were made to be big stage speakers (Which I know but im using them as temporary car speakers)

IK, that says the woofers are 2042h.

Spec sheet on that shows parameters:

http://www.jblpro.com/pub/components/2242.pdf

 

Spec sheet for JBL Designed sub using two of those drivers, with fr graph

https://www.jblpro.com/ProductAttachments/ASB4128.pdf