I have a 2006 gt, 4.6 with vortec supercharger, intercooled, 3.55 gears 5 speed stick, rear control arms relocated, mt drag radials,eibach lowering kit, 60 lb injectors, cobra duel electric fuel pump, 12 lbs boost, dyno at 474.6 at 6500 rpm at rear wheels, 437 ft lbs torque, what should this car be turning in a quarter and how much advantage would I get with 3.73 gears?

 

trackers, Car and Driver got the following:

Stock Mustang 2005, 4.6l, 3v, GT= 0-60(5.1 sec) 1/4 mile(13.8 sec)
This is about right for the stock ones I have seen run at the Drag Strip(w/Drag Radials). When you add a SC the "rule of thumb" is 100hp would be about 1 sec faster(1/4mile), 150hp would be about 1.5 sec faster, etc.
So if you gain 150 hp w/ a SC your Mustang should go low 12's (w/ traction). Now, that being said, with your other added modifications, I would guess you could shave off another four tents at the finish line. As far as gearing goes, I would leave the 3:55s in for now. Believe it or not, you might fare better with 3:31s or maybe even 3:25s. There are also a lot of variables to consider so take this with a grain of salt.

 

so your saying, with the right driver and if it hooks up, maybe late 11's? I did run it with the stock street tires and got a 2.89 60 ft, the put on mt drag slicks, 10 inch and dropped a full second to 1.84, but broke a control arm extender so had a bad quarter mile time. launched at 5000 and it really seemed to like it. so replace control arm extender and welded them this time haven't had it back yet, but can't wait til the track opens, also changed the drive shaft from 2 piece stock one to 1 piece aluminum, big weight difference, stock was 60 lbs, aluminum ,22 lbs. my speed shop said with that hp and torque the 2 piece was the weak link in the chain, the aluminum one is rated for 950 rwhp. thank you so much for you input, i'll keep you posted how it does

 

trackers, you are headed in the right direction. I like the 1.84 60 footer. I am pulling a 1.80 60 footer 12.4 second et @ 113 mph with my non aspirated 2014 mustang GT. I have also invested $3,000.00 in very trick suspension work, front and rear, along with a very serious diet that almost makes the car a hazard, along with NITTO NT05 radials mounted on light weight rims. You shaved off 20 pounds by going with the aluminum driveshaft. Remember, weight reduction isn't only healthy for humans. Dialed in correctly, in the direction you are headed, the high to mid 11s should not be a problem. My 1992 Stang with a modified 308 on a 150 hp hit of juice was turning consistent low 11s. Keep up the good work.

 

if I hit 11's, I will be thrilled, thank you so much for your educated response. I'm thinking now, that the car is capable, now it's up to the driver. as I stated before, it liked the 5000 launch with the slicks, so all things considered , weather, track temp, and my reactions, it could happen. I will keep you informed napierville drag strip opens around april 1'st that will be my first run this year, thanks again

 

every one says you need to break in a new clutch for 500-700 miles before racing it. what if your building a strictly track car that's not street able, not registered and only for drag strip? is there a clutch that you can but that does not require break in?

 

trackers, the typical break in period for a clutch is about 500 miles of mixed highway and city driving. It is recommended to take it easy on the new clutch until the break in period is over to avoid any potential damage. Allowing the clutch to break in will ensure that the clutch and flywheel seat together properly and you will get the best performance out of the combination. I know your delima, when stack car racing and drag racing we were faced with the issue of the dreaded "break in period." What I do is make a few passes to be sure everything is "seated" properly, and then race as if the clutch has 500 miles on it. I have never blown a clutch after making three half RPM passes. Then shift at staggered RPMs on the fourth pass. If anything is wrong, the fourth pass will bring it out. Your fifth pass can be a full all out pass.

 

hey sarge, curious, why would I want taller gears? wouldn't the hurt hole shot and acceleration?

 

trackers, as you increase horsepower, to much rear end gearing can put you through your torque range to quickly. This forces you to have to shift before your car takes advantage of the torque/ working power curve. The secret to maximizing your power output is gearing matched to your torque range. In 1986 I set up a new Mustang LX and we put 373 gears in it. It ran very well. Then I put a 125 hit of Nitrous on it, and there wasn't the improvement I expected. The Mustang is a high/quick revver to begin with, and I realized we were going through the torque curve to fast. I installed 325s and on the juice, the car ran like a raped ape. If you want to get real trick, start researching changing gear ratios in your T5. That is advanced, but worth knowing what the alternatives for maximizing your power are. Good luck. On the street I faver the 373 and 410 because most encounters are from a roll and you will get a great jump without losing traction. You can keep your present gears but if that T-5 causes you to lose traction in 1st and 2nd, I would look at changing my tranny gearing.

 

you do make a good point, with the supercharger and 12 lbs boost it does spool up pretty quick. so much so that I had the rev limiter pushed up to 6500 because I kept bumping it. I feel good shifting around 6000, but by bumping it up, I have a little margin. when they dyno'd it last time, the first pull was 501 at the wheels and still climbing when they shut it down, but they put me back to 474.8 at the wheels because they said the stock block would not hold at that high rwhp, . they said they felt safe where they re set it. all they did was take a whole lot of timing out of it, they said, if they block would take it, they could easily bump it up to 550 rwhp but even with the 3.55 gears it is hard to keep up with it. i'll see how it goes this summer, and may make the change to taller gears