661/601, 37psi, street tires, General extreme uhp oem size.

 

I would like to revive this post to see if any more people have tried the 4.11 gears as i am thinking about it myself, i have had a good read of the post and i think the whole gear ratio think is greatly dependant on power and traction and the basic math applied previously is not taking a whole heap of other factors into consideration. I have an evo4rs which came factory with something like a 4.8 and with 500whp needed 5th and 1st got almost no traction at all meaning when i hooked 2nd i was barely moving and bogged down once it hooked up. I changed to the gsr box and dropped 60ft and et, 0 doubt this was faster for my set up. Now i have 800hp and hitting the limiter again so thinking of going 4.11 keen to here actual facts ie before and after data from people who have actually done it. For the people advocating the use of 5th also consider that 5th on a 4.5 diff will be taller and there for have less torque than 4th on a 4.11 and this is where you can actually use the torque, having more torque in first is of no use when traction is the issue. I think it's almost impossible to use maths to calculate all the variables which is why people's opinions who have actually done it is more pertinent.

 

put a 26" tire on it and save your self the FD conversion.

the 4-5 shift kills your times because you're decelerating (due to air speed). I've seen my car scrub 6mph on a 4-5 shift. There are all kinds of calculators for figuring out how much horsepower is consumed by air resistance at speed. If you're putting down zero HP... that's negative HP lol... means you're slowing down. The higher the speed the worse the effect is.