my battery is dead...
 

so does it matter what car battery i put in? or could i just take one from another car of mine and use it because at the moment im a little tight on money until next week. the extra battery im planning on using came out of a big v8 so im not sure if it'll be good or if it'll have any effects at all on the rx7.

If it is a top mount, should have enough cca to do the job.

What you are looking for is that it will fit in the existing battery box and that the terminals are on the same side so the cables will reach and that the height of the battery will clear when you close the hood. Other than that the 7's do not require much in the CCA department or reserve capacity. :)

Sorry forgot to add the most important thing. After you get the new battery, have your charging system tested to make sure that it is functioning properly.

thanks i guess i'll try it then it and see if it'll fit.

height of battery
 

make sure the height of the battery is such that you do not short out against the terminals when you close the hood.