Hello
im not sure of the casting number on my heads, im pretty sure the arent the 882s, I do know that when I got them I ran them through mortec, and it came up as "made in mexico" 75cc chambers.
they have 1.94valves now, for 70$$ I can have them milled for 2.02s. figure a couple hundred for valves and springs.

how much of a gain will I see? I have to change he springs anyways, cuz im goin to a bigger cam in a few months.

 

Jacksh!t without other work.

All dependant on the heads they actually are, Your More likely (to the point of garunteed) to gain more from unshrouding the existing 1.94" Valves and cleaning up the Bowl areas Right above.

An even better option would be to Do the shroud and Bowl work, and Then add the 2.02 valves to the heads w/ a good 3 angle valve job.

But I don't think it is going to be worth your time and money with the heads in question.

But, back to the main question...

Just slappig some 2.02" Intake valves in an otherwise stock crappy head is not going to make a **** of differance.

 

Each part of the total induction system of an engine is simply a conduit of flow. The intake, heads, valves (including the cam properties), exhaust, etc. So let's do a thought eperiment.

Think of your engine a string of pieces of garden hose. Now imagine that they're all ½" diameter hose, let's say for the purposes of this experiment that there are 6 equal-length pieces, 50' each. Now mentally hook this up to your faucet and imagine the total flow capacity of the system. Now what would happen if you took out one of the ones out of the middle and replaced it with a 1" hose? How much effect would it have on the total flow capacity of the system? That's exactly what putting large valves in crappy heads does: helps pay the machine shop owner's kids' orthodontist bills. Nothing else.

I would not spend a single dime on those castings. It's a classic case of "pearls before swine".

Get some decent heads.