I know these get asked alot but the search is still down so I can't look at old posts. I think I wanna get the FRPP 4.10s. I want a blower but its too much $ so I'm thinking a little extra acceleration will keep me happy.

As I read in another post, the 4.10s wont noticably wear the engine more than my 3.55s, right? Also what are the rpms at in 5th on the highway. 55, 65, 75, 80?
Is it really that much of a diffrence in SOTP feel???

Also no chance in hell ford will let me keep the waranty 100% even if they install them right? haha

Thanks everyone!

 

since no one has answered...sotp is really good. rpm's at 70 are about 2300. Gas mileage (i know you didn't ask) doesn't change much (depending on how you drive). don't know about the warranty if installed by a ford dealer...you'll also need a tuner to adjust the speedometer.

even with ford gears you can still wind up with a little gear noise. i've got a little gear whine around 65 mph, but it's not very loud so it doesn't bother me much.

 

I have an '06 GT automatic, and I went 3.73's 2 weeks ago. I happy, but I was not as dramatic as some people described. I only lost about 200 RPM's,(tach-ing 2600 RPM @ 80 MPH now, used to tach 2,400 RPM @ 80 MPH) and according to my dash readout, I lost .3 mpg's! (for what thats worth) same kind of driving, highway cruising. It definitely made a difference, you don't have to go into the gas pedal as much for the same amount of acceleration, but I'm thinking maybe I should've went with 4.10's, then again I'm mostly highway driving with minimal track time so I can live with it.

BTW No gear whine at all, at any speed thanks to a good install (thanks Alfredo! Valley Performance) Gears will NOT whine if installed properly.

 

4.10s will make your car fly. yeah you will lose about 2 mpg. Top end believe or not isn't effected much or any at all being that I know but I do also have a brenspeed tune which gives me more rpms to play with. If you get the gears also get the Cold Air Intake with tune. My car revs at 3000 for 85 and I believe 2000 at 55. So what do you add like 150 rpms every ten? I have the 5 speed. I used to have all this written down.

 

Get the 4.10's. You wont be sorry. It will go up about 300 rpm at those speeds. Not that bad. Of course youll feel it more today with the gas prices tthe way they are.

 

here's a useful link
http://www.csgnetwork.com/rpmcalc.html

overdrive ratio should be .675 for the calculator

 

I wish I could trade you - your 3.55s for my 4.10s. In a day to day scenario I like them alot but in highly aggressive driving I'm constantly bouncing off the rev limiter, not enough "top end" in gears 2-4. 5th gear is pretty much an overdrive and thus useless on a road course. Right now in 4th gear I hit the rev limiter at around 100-105MPH, which is too slow on most road courses.

 

Yea I do alot of highway driving. I would go 3.73s but I feel it's not worth it 1. because I have 3.55s already and 2. I know I would like them and then just wish I had done the 4.10s. Just was worried the 4.10s would wear something out.

So top end really isnt affected? Not only top speed but I heard that youll have less acceleration at higher speeds with them too. True or what?

Also a couple of you guys mentioned the tuner. My car's not stock you know haha. I already have one....it's in my sig

 

Dude do it and never look back. That's b.s. on acceleration at top end. Ask the Cobra I had the other day. He only had me two car lengths.

 

That's interesting I have a 5-speed and got 135 out of fourth before the rev limiter said something.