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what am i doing wrong with my GT . why won't it go!!

2238 Views 11 Replies 8 Participants Last post by  RedRunner
Hey everyone I need some help from the guru's out there. Here is the situation. I have this 2005 Mustang Gt. I put a C&l cold air intake and A Diablosport tune. After perfecting my times at the track i got the car to run 13.59 in the 1/4 with a reaction time of .052 top speed of 102.65 now in the last week i went and put on the Steeda underdrive pullies, Put a set of Magnaflow exhaust and Reflashed the car with the Diablosport 93 C&L tune and ran 93 octane in the car my best time has been 13.572 with a reaction time of .047 at a top speed of 104.50 . Now i have been at it and cannot believe that with the pullies,tune and the exhaust the car did not get better. what did i do wrong? any suggestions. or maybe i have something else that i need to do. I am going to put the Zex nitrous kit on but for now i need to get the car right. can anyone help . Thanks in advance. :doh:
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Don't know about the pullies and tune, but the exhaust isn't really going to give you much of an improvement, Ford tweaked the stock one pretty well.
The C& L tune is a generic tune.

After you tune it withe the c * L tune, you need to have it on a dyno to get the correct a/f ratio...I am guessing you are running way to lean.

don't use any of that octane boost junk either. that stuf really doesn't bind to the gasoline and will just waste your will clean the system though.

Are you an auto or stick?

auto's have 3:31 gears while the sticks have the 3:55's

next mod should be switching to 4:10's then the 1/4 mile times will come down.

I was not too impressed with the tune, though it did take my car form a constant 14.1 down do a contant 13.8

pullies will help your top end speed and your reaction times are great, but do not effect your overal 1/4 time.
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Yes Crdshrp i was thinking of doing the gears to. Do you know how much it would cost me to do that. I have seen the ford racing gear kits on ebay for $200 . maybe ill do that next. can you suggest any place in the net that i can purchase these for the 2005 mustang gt 5 speed manual?
I don't know much about your car and the mods, but I can tell you about your track times. Your increase from 102mph to 104mph shows that the car has more hp. Your e.t. shows how well you used that hp. It can be traction, hitting the shift points, driver error, lots of things. Keep at it and it will get better.
Somebody touched by it above... and I wanted to make sure... your new tune is for C&L 93 oct, AND the pulleys, and maybe the exhaust... Be careful with NOS and 4-10s if you're no planning on getting stickies!

cheapest I've seen 4:10's 179.00

any speed shop should be able to swap aout the gears for 200 bones.
then use your diablosport predator to recalibrate the spedometer.
What are your 60-foot times?
stoopy the 60' times are about 1.986 and thanks crdshrp
Well it sounds like you're launching decently enough. Don't know how much it may help but there's some interesting reading about heat soak in this discussion elsewhere...
I got Ford Racing 4.10 gears last month. Love them. No whine and woke up my car from daydreaming:) Heard FFRP was the best, Have no regrets:)
My 05 Mustang has a 5 speed automatic with the 3.33 gears. I have the C&L, the Diablo and the Zex kit. Down here in the southern hot weather, I was running 13.7's without the Zex (on ET Streets). I added the Zex and had MV Performance tune it on the dyno. The first night out (last weekend), I turned a 12.5 with a 1.7 60 foot. This is just to give you an idea what the Zex kit does. It should get a lot better as the weather cools off.
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