Real World Flow Differences 2.08"/ 1.74" Valves vs 2.14"/ 1.81" Valves " Pictures Added"

I have a set of 452 heads that I took off a 470" engine we raced. They have 3/8" stem 2.08" /1.74" valves in them. The heads have had a serious amount of porting done and we moved the short side radius way over (offset rockers and epoxy), roof raised .350". This engine ran 5.60's in a 2100# foot brake door car in the 1/8 mile, turning the engine 7,000 rpms. No idea what they flow as it never mattered to us. When we built a 526" engine we used the same cam we had in the 470" engine, but used Edelbrock heads built the same way as we had done the iron heads. (offset rockers, epoxy). The new combination runs 5.40's, but we only have to turn it 6400 rpms. So the addition of 56 cubic inches, larger valves, and improved combustion chambers obviously helped the power production a bunch at 600 rpms less.

Fast forward 10-years and I decided to use the iron heads on a 499" engine I am building. The guides need some attention, so I am going to change to 11/32" and install new pro-flow valves. Since I couldn't find any 11/32" stem 2.08"/ 1.74" valves I had to buy 2.14"/ 1.81" valves and planning on cutting them down. Then I got to thinking about if there was really anything to gain from running them as is. This set of heads are a proven power producer and no doubt have tremendous air speed through the ports. I really don't want to mess up a good thing, but was really curious if I should maybe use the larger valves or leave a good thing alone. I probably wouldn't use the exhaust valve at 1.81" because I don't believe that matters as much as the intake size might possibly make.

So I am looking for hardcore data on what I might possibly gain.

Thanks,
Tom