So I'm stuck in the mid 11's right now due to needing a stronger clutch; clutch would slip every single gear, unless I waited until halfway through fourth to actually touch down to full throttle. I'm getting a new clutch, and I'm also building a new tranny and have the option of playing with a few gear ratios...

Are the ten second guys typically topping out fourth gear? Or are they shifting to fifth?
I ask because I'm trapping 123-124 right now at about 7500 in fourth gear on 24.5" tires, and my powerband is really only up to about 7k with a ton of midrange torque.
Curious if I should go with taller fourth and fifth gears, taller final drive, taller tire, or just shift to fifth lol
Car in question is in my signature below

 

Ideally, you want to reach the end of the track at or near the top of fourth gear... essentially at or near redline. Shifting into fifth gear will cost you three or four tenths in the 1/4 mile. If you cannot raise the rev limit, a taller tire or a taller final drive (taller 3rd or 4th gears are also an option) will be the fix.

 

Thank you. I did a ton of math and built some spreadsheets lol. And even taking your advice into consideration, I'm still questioning whether to just raise the rev limit, or shift to fifth.

Here's why, this is a graph of all my gears with 24.5" tire mapped out according to my dyno torque curve figures. Each dot is 200 rpm increment, with last dot of each gear being 7400rpm. Would you still say the same as above? Or would you actually recommend shifting to fifth after seeing this?...
(ignore the first gear curve. it's calculated, not real world numbers. I don't run full boost in first)

 

Wind it out, shifting to 5th is a no-no.

 

Yeah, I still say stay in fourth gear and run it out.

 

ok thank you guys.
Next mission, better intake manifold and bigger cams to bring that higher rpm power up