Max Valve Size to Pistons

[nivvy]

Do anyone know what the Max Intake Valve Diameter I can run?
I am going to be getting the New Indy CNC 295 EZ Heads - Max Wedge Ports,Fully Ported.
They Come standard with 2.19*1.81 valves and for only 75 bucks more I can go to 2.25 intake valve diameter which Indy says I will get 10CFM of more flow across the board!
10CFM is appx 20HP and I figure $75 for 20HP is a good deal!

I have a 4.375 bore with J&E pistons if this helps?

[Oldschool]

Race or street?  727 or stick?  If 727, what stall converter?  How heavy is the car?  Rear gear ratio?  Cam and intake carb combo?    

Need more info here....     

Sometimes bigger valves and ports aren't necessarily the way to go.  They will work great if you keep the engine turning some rpm's.  Big ports and valves are great for racing if the rest of the combo can support the flow.  It gets tricky trying to keep flow velocity high enough with big valves and ports when used in street applications.  Too large ports and valves kill flow velocity at low to mid rpm's.  This results in a sluggish feeling bottom end and lack of a crisp throttle response until the r's come up.  If you are going to drag race and keep the r's high enough, then you will see the HP gains you are searching for.  Just my 0.02.......   Others will soon chime in here...        

[nivvy]

Street driven but Eventually I would like to take it to the track!
.620 Solid Roller Cam
727 w/ 3200 stall , manual valve body
3.91 Gears may got to 4.10 or 4.30's(Indy recommends)
With the EZ heads I am going to get the Indy Single plane Intake 440-2RB 4150 flange with the 2inch 4150 to Dominator spacer.

Hope this helps...

[nivvy]

Full weight 72 Challenger w/big Block
I would say 3700lbs with me in it....

[Chryco Psycho]

I would contact JE with the piston # & see how much clearance they design into the piston Assuming the valves are located int he stock location

[Oldschool]

Street driven but Eventually I would like to take it to the track!
.620 Solid Roller Cam
727 w/ 3200 stall , manual valve body
3.91 Gears may got to 4.10 or 4.30's(Indy recommends)
With the EZ heads I am going to get the Indy Single plane Intake 440-2RB 4150 flange with the 2inch 4150 to Dominator spacer.

Hope this helps...

As I posted earlier, the bigger valves demand that A LOT of air be moving in order to keep the flow velocity high enough to realize performance gains.  It sounds like 500 inches under these heads will certainly do the trick.  In order to realize all the performance these heads offer the engine will have to get into the higher rev's pretty quick.  That is why Indy is recommending the higher ratio rear gears.  The higher the gears, the quicker the engine gets into the sweet spot.  As long as you are going to a higher stall converter, a 3800 stall might be better still than the 3200.  I run a 3800 in my car with no ill effects on the street. I also am running a 4:10 rear gear.  Not too bad on the street.  The 3800 converter allows the 4:10 to launch hard.  I think for overall driving, the 3800 converter and 4:10 gear combo works better than a 3200 converter and 4:30's.   Don't get me wrong, this engine is going to make some serious power, but it might be a little peaky, and rev's will be it's friend if you are searching for that last 20 hp.  It won't be slow on the bottom end, but it won't make the big numbers until the flow velocity comes up, which or course corresponds to rpm.
Also, which Holley 4150 are you gonna run? The 750, 830, 950, or 1000 cfm one?  If it were mine, I would go with either the 950 or 1000 with your combo.  This engine is gonna breath, don't allow the carb to be a restriction. 
I think this will be a beast when done and you will enjoy it.  It will take some tuning to get everything tuned exactly right.  I run two 4150's on my car and they are very tunable, it just takes some time to find exactly what your combo likes.  Just my 0.02 and there will be other opinions here to help you way more than myself.........     

[nivvy]

I was going to run a 1050 Dominator....Hence the use on the 2" spacer 4150 to 4500 flange...


Thanks for the advice...Oldschool...

[Oldschool]

I was going to run a 1050 Dominator....Hence the use on the 2" spacer 4150 to 4500 flange...


Thanks for the advice...Oldschool...

Sorry, I missed that part when I read it...          Should be a bad mofo when you are done......        

BTW---- MAKE SURE you do what Chryco said and be positive about piston to valve clearance with the oversize valves....   Don't need any parts becoming intimately familiar with each other...