I have an 01' GT with a stock bottom end, on my 4.6 litre 2V motor. My GT has the stock AODE transmission (built after April 01'), and is doing a good job with my mods. The following is a list of the power mods that were done to my GT:

1)Kenne Bell 2.1 polished and intercooled supercharger (9psi boost)
2)Accufab polished 75mm. throttle body.
3)K&N FILPK intake tube.
4)PMAS custom tuned MAF.
5)FRPP 39lb. fuel injectors.
6)FRPP Focus fuel pump.
7)Bassani stainless exaust from the manifolds back (W/Cats).
8)FRPP 4:10 gears
9)Custom tune

Before I had my Kenne Bell, exaust, throttle body, injectors, fuel pump installed in my car, my 4:10 gears were perfect for my car. My car would run through the traps right at 5,800 rpm's, which is right at redline. I would always shut off my traction control and my overdrive, to make my car roll through at 5,800rpm's. I went up to Tasca perfromance day last weekend, and had a bit of a problem that I failed to think of. With my new setup on my GT, I shut off the traction control and overdrive as I always have done. My GT had a stumble in second gear that I know I lost time with, and at the top of the track the rev limiter kicked in far before the traps. The car was jumping on the limiter, and I had to back peddle the throttle. I thought for sure I had done terrible, even though it pulled great after the second gear stumble and before the rev limiter kicked in. I could not even believe what my timeslip read, when I picked it up at the booth. I ran a 12.1 at 113.6mph., mind you I had to back peddle at the top end and the stumble in second gear! I had to run the rest of the day with my overdrive on, and I was rolling through the traps at 4,600rpm's and still running 12.1 and 12.2's all day! I know I will have to do a gear change, in order to optimize my time's in the quarter. The 4:10's are now too much gear for my setup. Does anybody have any suggestion's for a gear for my setup, using my trap rpm's and current gear ratio?! There must be a formula out there to figure out an optimum gear, for me to hit the traps at 5,800rpm's again?! Any help in this would be very much appreciated, I would like to hit the track again before the season ends, and run some 11-second times like I had figured upon.

Thanks, Dave

 

Can you leave it out of overdrive till you redline then shift it to overdrive?

 

I am afraid to do just that, as I tried shifting my 94' in such a manner and had to have my tranny rebuilt. I do not know if it was just time for that tranny to let go, or are you not supposed to change these tranny's in and out of overdrive while moving?! To this day I am nervous to take car in or out while moving, I always pull over and put the car in neutral before shutting the OD on or off. On one of my 12.1 runs last week I was pulling on an 01 cobra with some mods, until I hit OD and my car sat down and coasted. The 01' Cobra suddenly started pulling on me, but I managed to still run a 12.1@113.6 to his 12.3.@115.4. We both broke out of our dial-ins, and he managed to get me by two-one-hundreths! I had so much time and room after the car went into overdrive, that I looked over and watched him trying to come around me at the end. Has anyone out there had this problem, and tried shifting it into overdrive at WOT at redline?! I know my car has 11's in it, I can just install a 10psi. pully to make up the difference if I have to. The stumble in second gear is pretty bad too, that alone would put me in the 11's. I am shooting for mid 11's with the current setup, and plan on pulling the engine over the winter and going forged. I am knocking on the 11 second door right now, I just need somebody to answer and let me in.

Thanks, Dave

 

buy some cheap 15 inch stock mustang rims and run a taller tire, that way you can keep your 4.10s for the street (if you like them for the street) and still not hit the limiter on the track.

 

+1 If you do decide to change gears I wouldn't go any lower than a 3.73.

 

yup, run a 28inch drag tire, itll feel like 3.73s, and hook better then a 26inch tire with 3.73s...

 

+2 and those are some nice times . a shift kit should also help lower those times.

 

I would just get a taller tire.

 

The only racing that I do these days, is drag racing at the track. Even if I were to race the car on the street, 1/4 mile racing is all I do. I just bought brand new aftermarket 17"X10-1/2" wide Bullit wheels, so I could mount my brand new 12-1/2" wide Mickey Thompson drag radials on them. I wanted to keep the stock height so I would not lose my gearing, but it has certinally back-fired. I do not want to spend anymore money on wheels and tires right now, I would rather just match the gearing to my current setup. I was planning on changing out to 31 spline axles and so fourth anyway in the near future, and just need to calculate my optimum gear ratio. I also plan on running higher boost once I go forged, so I need to think about my future trap speeds a little as well. Does anybody know of any type of formula, that I can use to best figure out what would be good for me? I was thinking about 3:73's as well, but know that there must be a way to do the math to make sure. Thanks for all of the input out there, it really bothered me to not reach into the 11's. There are only two weeks left of the season at New England Dragway, and I need to get it right before it is too late.

Dave.

 

Once you go forged, you will be able to get more RPM's out of the motor which means you will be able to go alot faster in 3rd.

Just find your tranny gear ratio, and input your tire size and rear gear.

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