Getting an '86 na with issues

[GetLifted]

I'm buying an '86 300Z 2+2 na from a friend, but it has a small problem. At ~25mph the car starts stumbling and hesitating. If you accelerate past ~45mph it stops. Any ideas what could cause this?

If I get the above issue resolved, what things should I do to it? I know its not a turbo and I have no intention of trying to rice it out. I plan to give it a few little performance upgrades, some fresh paint, maybe redo the inside, drop in a good stereo, and then give it to my wife as her "fun" vehicle. If I like the Z experience, maybe I'll move on to a Z31 Turbo and actually try to make something with some speed.

I was considering doing:

Filter\Modulator replace to a K&N setup240 SX throttle body "conversion"Upgrade to a 2.5" exhaust.

Anything I should consider doing (besides just buying a turbo 300 instead)? I am looking to do upgrades that are cost effective...

[pylon_boy]

If the car is in poor shape to begin with repair it first. Do a full tune up. You'll probably need to address the suspension bushings if that hasn't been done.

[GetLifted]

Actually IMO, its in very good condition. It has a recently rebuilt transmission (~10K miles), body has no rust, paint is in decent condition, T-Tops don't leak. I plan to do a full tune up first, Timing Belt being high on the list. I'm was just wondering where I should start on the mods and if they are worth it. I also wanted to see if anybody had heard of a similar issue, maybe they could point me in the right direction...

[pylon_boy]

buying a z31 with problems is stupid. They are so cheap to begin with you can get one without problems for not much more.

BTW, no matter how good condition the car is in, the rear crossmember bushings will have to be replaced.

Go to http://www.z31.com. They are a much better forum than this for the z31.