I have a 92 rs 305ci I wanted to know how much changing my stock heads to 350 heads would do to motor, anyone know?

 

depends on what 305 heads u have and what 350 heads you want to use. heres some reading.
http://www.camaroz28.com/forums/arch.../t-141362.html

 

^ That link covers using 305 or 350 heads on a 350 engine.
Badrs has a 305 engine. 350 heads might be better, if everything is just right mathematically.
The 350's bore diameter is 4" and the 305's is only 3.736" (a little over 1/4" difference). Valve to cylinder wall clearance could be a close one, depending on the lift and diameter of the valves. Also, 305 heads have small 58cc combustion chambers (that's a good thing for compression). But if you get larger cc 350 heads, your compression ratio (and performance) is going to suck. You would probably be better off trying to find a pair of 305 HO heads. The 305 heads you have now are crap, and nothing can be done to make them performers. But 305 HO heads will really wake up your engine.

 

so is the thread correct in saying the 194 heads will fit and anything larger will not?

 

I don't quite follow what you're asking. In that thread they are talking about whether to use 350 heads or reworked 305 heads....on a 350 block. As far as possible clearance issues might be concerned (because of the chamber diameter differences), putting 305 heads on a 350 is not the same as putting 350 heads on a 305. I know someone who did the 305 HO head on a 350 engine trick, and the test drive did prove that it can work well. But that's not what we're talking about doing here.

 

will a head with 194 valves fit the 305. they are saying that the largest valve a 305 will take without mods is a 194.

 

depending on how much money you are willing to spend redoing your top end you might be better off buying a complete 350ci?

 

That's the kind of responses I needed to start with. Now my next question is where can I find these 305 ho heads and what's a resonable price to look at to not get ripped off. And what's a good intake and throttle body replacement?

 

did you check your head casting #'s? in 92 camaro's did come with 305 HO's. did you want to go carb or stay fuel injected? also were are you located?

http://www.americancylinderheads.com..._-AC192C1.html

 

OK, I think I follow what you're asking...I think!
The valve size issue would be within the 305 head itself; the clearance and amount of meat left between the intake and exhaust valves. There wouldn't be any clearance concerns between the 305 heads and 350 engine (as talked about in that thread), other than having domed pistons whacking the valves, etc. But you're asking if the 194 valves will clear the 305 block aren't you? Yes they would.