Dave2000GT

My usual highway spd is 70 MPH, my 2000 GT runs at EXACTLY 2600 RPM @ 70MPH in 5th w/ 4.10 gears. It is no problem whatsoever.

josh_0351

4.10's

ZW99GT

I vote 4.10 as well

HARD DRIVER

Well ****. I don't know but, if in the above example, Dave 2000GT, says 2600@70 in 5th. JD1969 says 90@3000(approx) rpms. It only takes 400 or so more rpms to go 20 miles faster? Is that about right? It seems like 90 would be higher but wtf do I know, hehe. Somebody clear that up for me, please. I also appreciate the responses to these same questions that I know have been asked 2,647,987 times[sm=icon_quiet.gif]

Also got my K&N cone filter last night. It still is sucking engine bay air though, but I still felt a throttle response and rev-difference.

code3GT

I have had 3.73's and now have 4.10's. I noticed a considerable jump in performance and not difference in mileage.

The Great Cornholio

Consider how much are you driving at 90 mph on your 90 mile round trip. 90 mph was just an example of the speed I have to run to hit 3000 rpm. A GT might have to run at 3200 rpm at 90 mph if the transmission is geared a little differently in fifth than mine. That's no big deal in my opinion. The advantage of 4.10s is primarily quicker acceleration, and the examples of rpm at various speeds only show that 4.10s will not wind your engine up to excessively high rpm while cruising, except for when you want them to of course.

SonicBlue Angel

go 4.10's. Don't ask me why but that is what we put on my stang. To me it seems to run really good. Don't know much about this stuff but I'm trying to learn.

The Great Cornholio

4.10 is an excellent upgrade to any Mustang, V6 or GT, daily driver or occasionally driven.

2000GT4.6

None of you can tell him what RPM it will run at what speed because unless I am missing it he has yet to say what year the car is. Also, is it a auto or a manual.

A T-45 car will not run the same RPM as a 3650 car. I wouldn't put 4.10s in a t-45 car. In fifth gear my '45 with 3.73s tached almost exactly what JDaniels GT was with 4.10s and a 3650.

The Great Cornholio

Well take the example of my wife's (SonicBlue Angel's) car in post #17 above. It's a V6 automatic with 4.10s and it gets to about 80 mph before hitting 3000 rpm. That's perfectly fine for a daily driver in our opinions, and I doubt Hard Driver would get to any higher rpm at that speed in fifth gear in a GT, regardless of whether it's a 3650 or a T-45 transmission. He can post what he has though and go from there.