ok so i have no idea what so ever when it comes to the internals of a engine so i do know that if you put in a better cam you get better hp

what i want to do is replace mine to get a little more hp when i have my valve seals and head gasket done i plan on ordering it from summit racing

info on my car:
1. 1987 iroc z28
2. 305 tpi with no mods
3. no mods to transmission that i know of
4. has 120xxx miles(if the odometer didn't rolled over already)

the cam i defiantly want to do is there any other internal upgrades that can be done wile its torn apart ill have 3000 to work with and i was told it will take $700 to do the valve/headgasket

i plan on upgrading the intake with parts from spectra (its for hondas i know but its cheap and i did it to my pathfinder an gained about 2 mpg and better acceleration) the exhaust i plan on doing a full upgrade headers,y pipe
i live in new york do you guys know if i have to have the cat or can i get rid of it and just run a straight pipe to a muffler and call it good

 

You should consider replacing / upgrading the valve springs to handle the lift of the new cam. Do you know which cam you might want to use? I have been very happy with mine from comp cams. You should see a considerable difference, considering that you have the small (penut) cam shaft to start with.
Make sure that the heads have enough clearance to handle the lift of the new cam. Stock 081 heads don't flow more past .5" valve lift, so stick with something below that. Something with a .48 to .49" valve lift with the stock rocker arm ratio is about as high as you may want to go.
You may want to consider putting in screw in studs while you are at it as well.
Should wake up the motor a bit.

 

like i said i have no idea when it comes to the internals of the motor so i don't know how to even read the specs of a cam but i see alot of the people on here run the lt1 cam so i was thinking that but im not sure becasue i thougth the lt1 was only a 350 and would a 350 cam fit a 305 motor?

 

The cams are physically the same size so they interchange
It is the change of cam duration and lift on the cam that makes them different.
In your case the LT1 cam is a little bit " bigger " than your 305 cam so it gives a performance increase

 

ok so do you think with the lt1 cam I would get a noticeable difference ?

 

You will get a noticeable difference of maybe 10 to 15 hp. However, if you are going to have the heads off, I would go a bit bigger than the LT1 cam. LT1 cams are similar in size to the L98 cams, which are the same cams that went in the 305TPI 5 speed cars. So, in terms of power you would probably be in the vicinity of a 305TPI 5 speed f-bodies.
Do a little bit of research and explore. There is a number of computer friendly cams out there and with your car being a MAF car, you would have fewer issues when it comes to the tune of the car. Although, you would want to do a wide band tune on it for best results.
Many members here have been happy with the Crane 2032. I have been particularly happy with my comp xr258hr12. The comp xr264hr12 give you a bit more lift and duration and is also a good choice. I went with the slightly smaller cam because I wasn't prepared to tune immediately and didn't know how well my speed density car would do with the slightly larger cam.
Take your time reading and looking into this and good luck with your car.

 

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Wow. Guys, SEARCH. I learned half of the crap I know from Googling like a mad man and the other half from taking the leap and applying what I had Googled!

 

what is a speed density car iv read this on a few post and i am lost?

 

In 1990 GM switched from using MAF (Mass Air Flow metering) to speed density (MAP or Manifold Absolute Pressure) for engine management. Your car uses a mass air flow sensor to measure the amount of air that enters the engine. Based on that the computer calculates how much fuel to dump into the engine.
On speed density cars the computer measures the air pressure in the manifold using a MAP sensor, and then based on engine load and such determines how much fuel to dump into the engine.
MAF is more forgiving in the sense that it can compensate better for minor changes such as a cam upgrade. It will still benefit from computer recalibration.
Speed density on the other hand does not compensate as readily on its own, and requires computer recalibration to run right.
Even with a smaller cam, my car ran too rich at some points and too lean at others after I got my new cam installed. Burning a custom chip for it after monitoring how the car ran using a wide band oxygen sensor made a huge difference.
Your car will probably run a little better than mine did initially, but will still benefit from a tune. This is just a very brief overview of the two systems, but there is alot more detail and more accurate explanation of this on this board.