How much top end will I lose by putting 3.73's into an A4 LS1? with now 3.23's

 

If you're talking at the salt flats, with 3.23 top speed is 203mph, the 3.73 only 175mph.

 

WHAT?????? LMAO! I hope you're joking! Top speed is in the upper 150's, maybe low 160's.....MAX!
On to the topic of the post! LOL Going from 3.23's to 3.73's is maybe a 10 mph drop.....not enough for the average driver to notice. It may not even drop you that much if at all. Theres a link to a calculation on this site that could probally tell you. You will notice a higher RPM's when cruising on the highways, but how many times have you ever hit the top speed in your car? Probally never! I know I'm too scared to go that fast! LOL
Mike

 

I usually Pin my speedo two to three times a month.

 

Well thats just the cause of having a heavy foot..

 

Those are correct top speeds for those gears if you have the horsepower.

http://www.f-body.org/gears/