I have a 91 ser how do you know what kind of engine it has. I know it a 2.0 but there alot of sr20de sr20ve i dont know what any of this means.
Also i have over 200,000 miles on my car what do i need to change to lower that milage?
And sometimes when i start the car and when i have my a/c on its squeeky like its a belt or something what can it be?
Okey thats it for now thanks!

You have an SR20DE. To lower your mileage, get a new Japanese SR20DE from here www.jgycustoms.com
...and replace your a/c belt

Has the timing set ever been changed (tensioners, guides, etc)? Its recommended it be changed every 100k miles, even though I haven't yet. Also just a general tune-up should keep it running.
As long as the car wasn't harshly abused there is no reason why it couldn't reach 250-300k miles.
Get an estimate on repairs, but likely a new motor swap will be more reasonable and well worth it in the long run. > www.jgycustoms.com <

thanks for the info guys but heres another ? the motor part : what type of moter is better theres so many different ones u12 bluebird, u13 bluebird, ect... i dont know?

Just get the regular JDM SR20DE unless you know what your getting into with a Bluebird or any SR20DET swap.

"unless you know what your getting into with a Bluebird or any SR20DET swap." what does that mean?

Well, all of those engines have a stock turbo and cost about $1200 more than a regular DE. You'll also have to get your ECU reprogrammed($500) and at least cryo-treat your transmission($300). Then you should probably get a turbo timer($100), a heavy-duty clutch($300), use premium gas full-time, and be careful with your tires so as not to burn them out every 3 months.

alright thank so much!!! sorry to ask so many questions