4.10's installed

[04Stanger]

Hey, just got 4.10's installed yesterday and am trying to figure out if they calibrated my speed correctly. I have an 04 GT 5 Spd, and I am taching 2000 rpms at 60mph in 5th gear. I have seen where people posted that it is higher than this, however, I have also seen a couple of people post that on the 04 the Tremec 3650 5th gear is .62 and not .67 ratio. Is this correct? Anyone else with same year car and setup can let me know what they are taching?

Thanks

 

[Give Me TP]

I believe the 5th gear ratio in the Tremec 3650 is 0.67 for GT models. Mine is 0.62 because of the 3.55 stock gears used in the Mach 1. My car runs at 3,000 rpm at 90 mph with 4.10s, and about 2,650-2,700 at 80 mph.

 

[04Stanger]

So if I tach around 2500 at 75 does that seem about right?

 

[Mossberg]

So, how do they feel?

 

[propellerhead]

Won't autos be a little different?

 

[triggz]

the autos o/d ratio is .7, the 5spd is .67

a 5spd with 4.10s will tach a little lower than an auto with the same gears.

 

[5.O STANG]

3k at 90 is correct

 

[04Stanger]

They definitely rev out a lot quicker and the car is not struggling at lower rpms. I have not been able to get on it yet though because they said to take it easy for 2-300 miles for breakin. Not sure if that's necessary, just being safe.

 

[propellerhead]

The break in on gears is overrated. When you bought your car off the lot, did you wait 200-300 miles? I gunned it leaving the dealer when I test drove it. I'm sure others did before me. But I rolled back into the dealer and bought the car.

 

[menasci]

With 4.10's and a T45 Tranny I rev around 2900 rpms at 80mph.

 

[Give Me TP]

So if I tach around 2500 at 75 does that seem about right?

Yes

 

[jasonh_86]

let us know how they feel when you get on it, i'm thinkin about some 4.10's for mine but i'm not sure.. i've got 3.73's right now tho

 

[BennyBlown2v]

The break in on gears is overrated. When you bought your car off the lot, did you wait 200-300 miles? I gunned it leaving the dealer when I test drove it. I'm sure others did before me. But I rolled back into the dealer and bought the car.

lol...so you're saying that laying on it with fresh gears, fluid, bearings, etc., has no chance of adversely effecting the longevity of these parts?

 

[Give Me TP]

Of course it does, but laying on it at any time whether they're new or old could adversely affect longevity. I didn't follow any break-in procedure with mine and they have given no indication of problems for the last 16,000 miles.

 

[04Stanger]

I did about 3 short runs without getting on it, and let it cool down afterwards. Today I got on it at lunch and I took it sideways through first and second and part of third without getting on it WOT but pretty close. I would recommend 4.10's over 3.73 any day, I was a little worried about highway revs, but I am at like 2200 at 70 mph, that's not bad at all. I wouldn't worry about the revs on the highway you shouldn't have any problems.

Now what should I do so I can plant the power to the ground better? Need to keep it somewhat cheap, tires? I have 245 40 17 Michelin Pilot AVS or something like that. Would a 275 be okay on the stock rims, that's what I would like to put on the back with 255 up front. What else could I add for traction? Would subframes help?

Thanks

 

[scalder]

275 Nitto's and a good set of LCA's would be a great start!

 

[Bullitt0616]

u guys are funny believing break-in periods are useless.

ever bought a new pair of shoes?

different application, same philosophy.

 

[Give Me TP]

Ha-Ha-Ha now THAT'S funny!!!

 

[Mike97gt]

you will love your 4.10's the first time you hammer it... day and night difference.. BTW it sounds like they fixed your speedo.. mine is not calibrated yet i read about 100 when i am at 3000 rpm's

 

[menasci]

I've got 4.10's.
They are very nice, but I think people over exaggerate their claims in performance.
I've seen claims of:
-Losing contol
-Inability to start off in 1st gear without spinning tires
-Relearning how to drive
-Throwing the car sideways all the way through 3rd
I suppose if I revved to 3k and dropped the clutch I would have these problems too.
Perhaps these people are only reporting in terms of racing at the track.
Personally, I just slowly come off the clutch and press the accelerator and I'm just fine.
I noticed a nice difference, but I didn't shiitt myself the first time I got on it.
Perhaps if I drove a stock GT again I would think differently.