i need to know what i can put on my 1984 vette to increase horsepower and increase top speed

 

It all depends on how much money you have, and how much of the car's day to day driveability you want to destroy in the process of making it unique, faster, and more exotic.

First: look over the car very thoroughly (if you know a lot about cars) or find a really good mechanic and have him/her go over it with a fine tooth comb. FIX EVERTYHING that needs attention, that's even suspect or in less than perfect ocndition, now. You will not regret this even if it costs so much you have to delay when you start modifications. Modifying the car will make anything marginal break sooner, and there is nothing worse than spending a lot for some cool mods only to have you car sit for a month because rear u-joint broke and you haven't the cash to fix it, etc.

Second, make sure you know exactly what you have now, as much as you can. Very few 20-year old 'vettes are stock, particularly late 70s and mid 80s. Your car came from the factory with 205 HP I believe, and a claimed top speed of 155 mph, although my own experience (in 1984) was that a new one could only do about 145 or so under average conditions. Many older vettes have a whole bunch of serious mods already. Find out what you have so you know where you are starting. If you don't feel confident you can tell, ask your mechanic to check and make a list for you of everything he or she thinks has been modified (might be hard to tell if the cam has been changed, etc).

Then decide what you want (a fast daily driver, a street/strip car (set up to do really well at the track, but drives well on the street), a strip/street car (legal and licensed but no a joy to drive on the street), a road race car, etc. And be realistic about much you can spend. Make a long term plan, not in detail but pretty much right -- no use spending $3K on this engine only to decide in a year you want to pull it out and replace it with a bigger one, etc.

If you enjoy hot rodding as a hobby then you may just want to incrementally add and upgrade gradually. This can be a lot of fun -- a real hobby -- half the fun being doing reserach, talking with folks, etc. , and deciding exactly what parts you want, etc. Roughly in this order and the small mods you would make:
- long-tube headers and better exhaust
- better air intake (cold air induction, etc.)
- better intake manifold and throttle bodies, etc.
- upgraded cam
- upgraded wheels and tires
- new heads (ported, etc).
- new, stroked block
but the condition of the car now and your budget might change this order (e.g., your mechanic determines that the internal engine is marginal. then rebuild the short block now, and while at it put in a stocker (383 rather than 350 cubic inches).

If you are in a hurry, you can cut out all that incremental step by step stuff and "nuke it" over a weekend or in one week with a crate engine. This is a new engine, literally in a crate, with just about everything you need already assembled: open the box, take it out, drop it in the car, connect up wires and pipes, and go. General Motors Performance Parts offers small block V8 crate engines from 290 HP ($1700) to about 425 HP (a model called the ZZ383, about $6000) that will fit into your car without too much trouble: they are basically modified 350 cubic inch engines like the one in your car (they sell other crate engines up to about 600 HP but those WILL NOT fit in your car. Other companies sell other crate engines up to 427 and 500 HP. With any of these engines, subtract about 20 HP to make the rating equivalent to what it will be once installed in the car (the 425 HP ZZ 383 would produce roughtly 405 HP, or about twice the HP a stock '84 vette had from the factory).

One final recommendations. Don't be too eager to go too far with the mods. You can turn your daily driver into something that you either can't or don't want to drive every day. Make sure that is alright if you go to extremes. You can see my 'vette in the Gallery on this forum. It has a real 640 HP, from mods that cost much more than the car cost new. But it is now too valuable and a bit too extreme to drive every day. That's okay because I have another car as a daily driver, but that's the only reason its okay.

And write back when you find out more about exactly what you have and its condition. I'm curious.

Oh, and a final word. Be VERY CAREFUL if you want to take it up to speed and see what the top speed would be. Until you have it in really good condition and are experienced with it, take care. Things that are fine at 70 mph break at 140, and the condequences tend to be much more severe, too.