Is 208 your target speed? If so, I'd grab the 2.28 or the 2.41. Your max hp is going to follow your max torque by 1000-1500 rpm, and hp is what gets the job done. I think you'll lose too much hp when you shift into high gear, and never recover.
No KK we ran 215 last year , we're hoping for a bit more than that, the motor continues to make power beyond 5350, we'll be running it to 6350. We wont have a chance to set up the new ECM we have so we are just sticking a finger in the wind. If it falls on it's face we'll fit the 2.28 at the lake. We aren't confident of pushing it beyond 6350 and so there's no point running the gears we ran last year.
We'll be shifting into top at about 170mph, the rev/power drop will still be pretty good there.
I think I'd vote for the 2.28's also. Not sure what combo you are running and if you are running a 1:1 final gear or not but with a 2.41 and 28 inch tires and 1:1 4th I get the following using my spreadsheet:
Rear End Ratio===> 2.41
Tire Diameter ======> 27.80
Fourth Gear Ratio ==> 1.00
MPH............RPM..In..Fourth
200.....................5831
205.....................5977
210.....................6122
215.....................6268
220.....................6414
Were you running about 6300 at 215 like above? If so then with the 2.28 you would have the following:
Rear End Ratio===> 2.28
Tire Diameter ======> 27.80
Fourth Gear Ratio ==> 1.00
MPH............RPM..In..Fourth
210....................5792
215....................5930
220....................6068
225....................6206
230....................6344
235....................6482
215 mph to 230 mph at 6300 is a pretty big jump in HP required to do it. Now let's look at the 2.14 gears:
Rear End Ratio===> 2.14
Tire Diameter ======> 27.80
Fourth Gear Ratio ==> 1.00
MPH............RPM..In..Fourth
220......................5695
225......................5825
230......................5954
235......................6084
240......................6213
245......................6343
250......................6472
Now 6300 is over 240 and 215 that you ran is 5566 rpm. I'd go with the 2.28's to start like Chris suggested. I think he had a good plan.
The above info can be figured on the spreadsheet here in just a couple seconds....
http://purplesagetradingpost.com/sumner/bvillecar/bville-spreadsheet-index.html#Four%20Speed%20CarI've also added another feature to that spreadsheet. If you know from your dyno runs how much HP you had at say 6300 and you ran 215 you can use the spreadsheet that figures HP requirements at a different speed based on a know one.....
http://purplesagetradingpost.com/sumner/bvillecar/bville-spreadsheet-index.html#Horse%20Power%20Needed...to figure the HP requirements to run 100 mph. Then put that HP figure into the first spreadsheet for speeds at different rpm's and it will tell you the required HP needed for all speeds from 30 mph up. It would tell you the HP you would need to go from your 215 to say 230. The nice thing is that if you have done a dyno pull and you know your HP curve at different rpms you can use the spreadsheet and see how much hp you need at a speed after a shift. The spreadsheet will show you the rpm in the next gear. You can compare it to the dyno numbers and see if you have the HP at the new rpm to accelerate and probably have an idea if the acceleration will be slow or faster. I'm going to post more about this addition in the "Formula Forum" soon,
Sum