Picking gears

Mopar Performance 360 cid 380 hp rated

RPM...TQ.... HP
2500 380.6 181
3000 402.9 230
3500 415.1 277
4000 437.8 333
4100 439.5 343
4500 437.1 375
5000 416.3 396
5400 398.6 409
5500 388.6 407
6000 343.9 395

The thing about race-gears on the street is that with 400 ish HP, any more than 10 or 11 to 1 Starter gear is kindof a waste. What I mean is a if your 400hp engine has a stout bottom end, say on account of it's running nearly 11/1 SCR, then an 11/1 starter-gear will go up in smoke real easy. With an automatic there is an initial TM hit in the TC,on the line as well; meaning a 10/1 starter is more than you need.
With that in mind; 10/2.45=4.17s is the gear of choice. So you can round that either way; 4.30s or 4.10s.
Now this stout 400 hp-SBM is gonna start making power around 4000 rpm, which is about 30 mph, unless of course it is spinning. And it's gonna want to rev at least 6500 at the shift to come in at 3850.Well 6500 at the top of first,not spinning is about 50 mph.So now you drop into second at 50 mph doing 3850. 60mph will be 4620. So during the hardest part of the run,from 50 to 60 mph, the engine will be stuck at about 300 to 380 hp. Quick math says average hp from 50 to 60mph is 340 :(
So you smoked off the line to 50, slammed it into second, and now are struggling to get out of that hole.
Now work it out with 3.55s
The starter gear is 3.55 x 2.45=8.7 plus say 10% in the TC for a few feet =9.57,Perfect. Then the TC gets down to business and you hit 5670@50mph. This being about 400hp. By 60 the engine is well past peak-power, spinning 6800, and probably still making 375hp. So now, during the hardest part of the run, the engine will be putting out 400 to 375hp. Quick-math says average hp from 50 to 60 mph is 387.5hp :)
If you can't make race gears stick on the street,then, there is no point having them. I've run: 5.13s,4.86s,4.30s,4.10s,3.91s,3.55s, 3.23s.2.94s,and 2.76s. Guess which are my favorites.

Choose wisely grasshopper