91 Sentra, transforming, any tips?

So, I was thinking of buying an '83 Porsche 944, failry nice condition, for about $4,000. My friend suggested that I invest my money into my 91 Sentra E instead of buying a different car. My main problems with it is that it runs rough and loud. It isn't smooth, at all, you can feel every little bump. And music is constantly drowned out by outer road noise. So do you have any suggestions of how I can make it run smoother and cut the road noise down, as well as the price estimate? Also, all of my manual windows are getting stiff and hard to roll down and up, can someone tell me how to fix that? Do you also hav any suggestions on how I can completely transform it so it runs like new? I want this car to be as nice as possible, without spending too much. Thanks.

sounds like you need to buy a new car, and not that porsche. 4k will get you a decent condition 95-99 200sx SE-R or, if you can find one, a not bad b13 SE-R. both would be easier and cheaper to maintain and own than the porsche. and easier and cheaper to make fast.

Get new tires and have your suspension repaired. All of it. Should take care of most of it.

Well, I bought it not even 3 months ago for $1,000... So I want to hang on to it for awhile. I've also heard that these bare bone sentras have a LOT of potential. And great gas mileage (30-40, even though I'm barely getting 25 through combined city and highway... I changed oil, air filter, and spark plugs, fuel filter isnt concerning me due to the only symptom being less mileage). I think the rough ride is just standard, and I'm more used to newer cars. Would better suspensions and new tires make it more quiet and more smooth, and is it worth the cost? (estimate?)

high sidewall tires.... think 45-55-65..... new suspension bushings, new shocks and springs, pull your carpet and old sound deadening stuff and replace with new, change fuel pump and filter, flush the rad and tranny, fuel system cleaning and maybe a few aftermarket goodies to give it some pep, you should have yourself a great little car for around 1500 at the very most..... i fyou want to spend some more money and want it dead quiet in your cabin you can have your floor, firewall and door panels coated with dynamat, you wont hear SHAT!

Well, I'm a junior in highschool with about $480 a month, not to mention $100 a month for the car, insurance, gas, girlfriend (thats the most expensive part). I just need the essentials. I was thinking new tires (they are getting worn, pretty hard, and little cracks near the rim) and that Dynamat sounds interesting... How much for what you told me, and how well does it work? Should it be professionally installed?

that would cost more than the whole rebuild i described, the stuff costs like 100 bucks for 10 square feet or something like that, it should be professionally installed because its a PITA to do yourself, you have to heat it up REALLY hot, as in torch hot to get the adhesive to work, they do make a spray in version but idk how well it works

i know how money is dude, just take your time, one week buy two tires, then next week buy the other two, then once you have tires you can start saving for shocks, after youve got them then go for your fuel pump and filter, just peice it together, after you get everything swapped you will love that car