[slikirish]

Hi everyone. I just picked up a one owner 2004 mustang GT 5spd, 2 and 1/2 weeks ago. I'm coming from a ford focus, so the power is obviously very nice. The car was kept stock except the dealership put a full magnaflow exhaust including x pipe and HFCs, and smoked headlights and tail lights on the car.

My questions is gears 1 through 4 seem very close and then a big drop to 5th. I was wondering if the car may have 3.73's or maybe even a 4.XX in it. Can someone with one of these sets of gears give me a rundown of what MPH each gear redlines at, or what RPM the car is turning at a certain MPH in a certain gear?

I seem to turning about 2,100 RPM at 80MPH in 5th gear, 1,000 RPM at 40 MPH in 5th, and 1st seems to redline 30-35 MPH, and 2nd redlines between 55-60 MPH.

Any help is appreciated.

 

[slikirish]

Sorry for the double post

I also seem to be getting about 18 MPG no matter how I drive the car. Is this normal for the GT, or could this also point towards having a different set of gears in the car?

 

[dcook_14]

Those are about the same rpms I run and I have stock 3.23s. Even with those gears it seems like I have to shift quite a bit in the first four gears. 5th is an overdrive gear, that's why there is such a big drop off.

Jack the back end of the car up and spin the tires while someone else watches the driveshaft to see how many times it goes around. If it goes around:
A little more than 4 times - probably 4.10s
A little less than 4 times - probably 3.73s
A little more than 3 times - probably stock 3.23s

 

[MiddleAgeMustang]

Take a look at this thread and do the math.

http://www.moddedmustangs.com/forum...vs-4-10-took-couple-hrs-2-complete-enjoy.html

 

[ZenMGT]

The 5th gear is very tall your transmission. I just got my '02 two and half weeks ago too! I was surprised at the difference between 4th and 5th as well,,but it's nice for hwy cruising.

The rear end gearing doesn't impact the 4-5 gear difference. Couldn't tell ya more about what gears you do have though - still getting used to mine

Could always jack up the car, rotate the rear wheels one full revolution, and count how many times the drive shaft spins.

My mileage sux unless I'm on the hwy too


<<<<<two other peeps above me beat me to it

 

[slikirish]

Thanks for the fast responses guys. Never thought about lifting the rear end up and counting driveshaft revolutions. I've never had a rear wheel drive car before. Have to say I'm very impressed with the way the car will rotate through a corner with throttle steer.

One other question. Is it possible to get the car to 300WHP with bolt ons, or are cams and/or boost required for that kind of number?

 

[DiZzyBonne]

300 requires a lot more work than just bolt ons. If you were to get boost, you would be well in the 360+ range depending on the PSI and tune.

As for your gear question, I have a chart somewhere that covers gears and their RPM at various MPH.

 

[slikirish]

Take a look at this thread and do the math.

http://www.moddedmustangs.com/forum...vs-4-10-took-couple-hrs-2-complete-enjoy.html

That thread is INCREDIBLY helpful. Looks like I have stock gears based on the 80 MPH RPM.

 

[MiddleAgeMustang]

I'm new around here too. Glad to be able to help out regardless.

 

[pyschopath76]

now that you have figured out that you have stock gears.......go out and get some 3.73 or some 4.10's. i like the 4.10s myself.......you think you like the "power" its putting out now......change them gears and watch yourself get the "OH" face!!

 

[dcook_14]

That thread is INCREDIBLY helpful. Looks like I have stock gears based on the 80 MPH RPM.

Dont forget to give reps when someone gives you good links or information

 

[pyschopath76]

+1. share the love with all the peeps in here that give up that good info!!

 

[slikirish]

I was thinking 4.10's. Are they difficult to install? Like i said before, never worked on a rear wheel drive car before.

The planned mod list is CAI, full eibach sportline suspension, gears, and maybe eventually boost of some kind.

 

[DiZzyBonne]

Unless you have the proper tools and experience, I wouldn't recommend installing gears yourself.

 

[slikirish]

Unless you have the proper tools and experience, I wouldn't recommend installing gears yourself.

That's what I was thinking. I've a got a buddy that builds and races late model dirt cars, I'm sure he could do it for me for a case of bear.

Do the gears throw off the speedo or RPM gauge, or are the run seperate from that. Reason I ask is b/c when my uncle did gears on his Mark VIII, he had to have the car tuned at the same time to correct some sort of issue. Not sure what the issue was, thinking it was something to do with shift points from the ECU which I wouldn't have to worry about, but not entirely sure.

 

[slikirish]

BTW, here's a pic of the new baby

Can anyone tell me what wheels they are? They don't seem stock for GT yet they have mustang centercaps. Windows have since been tinted 20%

 

[MiddleAgeMustang]

Wow. Nice ride!

I absolutely LOVE the color!

I don't know about the wheels though.

 

[slikirish]

Thanks buddy. It looks a little orange in the pic, IRL it's bright red, but with certain light or at certain angles, it does give off an orange hue.

 

[norcalam2]

I like my 3.90's!! I think based on the pros and cons of 3.73's vs. 4.10's put 3.90's in a good place.

 

[carnut59]

they look like 1999-01 cobra rims, could be wrong.