Here is some stuff for you to ponder. I've added a feature to a couple of my spreadsheets that give you speed in gears at different rpm. That is if you know how much HP it takes to run a certain mph the spreadsheet will tell you the HP needed for all the mph intervals on it. Since it also shows you the rpm in each gear for those mph intervals you will know from your dyno pulls if you have enough hp to run the mph at that rpm in that gear.

To use it in your case I took your 270 HP figure to run 204 MPh and plugged it into this spreadsheet...

found here...

http://purplesagetradingpost.com/sumner/bvillecar/HP%20Required%20for%20new%20speed%20-%2012-20-13%20-xls.xlsYou can take the 32 HP to run 100 mph from that spreadsheet and ...

...plug it into the spreadsheet above where the blue arrows are. I took a guess at you 1st, 2nd and 3rd gear ratios and tire size but the final 205 mph is close to the rpm's you posted. If the 3rd gear is close and you shifted at say 180 at 6246 rpm ( I think you shifted at 175 at 6000) you can see that you dropped 1619 rpm on the shift to 4627 and at 180 mph you needed 187 HP (left red arrows).

So if from your dyno pulls you made at least 187 HP at 4627 rpm you should accelerate which you did. Of course the more you are over 187 HP at 4627 the harder you will accelerate. So seeing the new rpm in the next gear and being able to look over and see the HP needed there you can make some gearing decisions.

Now looking further down the chart...

...we can see that with the 2.14 gears 6300 would be 240 mph and would require 442 HP at that rpm to run that speed. If you aren't making that HP then a lower gear is going to do better.

The spreadsheet with the HP needed at the speed intervals can be found here...

http://purplesagetradingpost.com/sumner/bvillecar/SS%204%20Speed%20Excel-1.xls... and if there was interested it could be added to the other car and/or motorcycle spreadsheets also,

Sum