So I’ve got the following mods installed on my 2003 auto GT:

CAI
Cat Back Exhaust
X-Cal 2 Tunes

I’ve really come to enjoy running the car at the track and I want to cut down my ETs a bit more. I would like to accomplish this while keeping the car street legal since it’s my daily driver (for now) and since I would still like to be able to cruise around with it.

What other mods can I do to get my times down? Keep in mind I don’t want to go too crazy.

I think my next move is street legal slicks. I’m having issues keeping the tires from spinning at the line and heating them and changing the pressure hasn’t worked. This will also allow me to get a completely new set of wheels so I can use my current set for the slicks and the new set for the street tires

I was also thinking of a upgrading the throttle body and plenum but wouldn’t that require a change to the mass airflow sensor as well?

 

I currently have an 03 auto GT (completley stock)
What times have you managed so far with those mods? just curious.

Since you already have a programmer and a CAI, why not consider a catted midpipe? You will pick up a few HP and still be street legal.

It is a tough choice though! Good luck!

 

My fastest run the other night was 14.32. I spun a lot on that run so I might be able to do a little better then that.

 

not bad for an auto car. what mph are you running?

depending on your State emission tests I would go with a off-road(non-catted) X-pipe. There is much more hp to gain with the mid pipe then anywhere else in the exhaust.

But in terms of 1/4 mile performance a set of gears or tires will net you better results.


also with the off road x-pipe make sure to get mil emliminators so the computer doesn't throw a code and even places that do check emissions you'll still pass.


edit almost forgot...on an auto car a shift kit is a must!

 

**** i keep forgetting things...also a new upper intake plenum will gain pretty good hp. like the dragon one from steeda

 

Running just under 97 MPH, I think the 14.32 run was 96.97.

My father in law does my inspections so I shouldn't have to worry about the cats. Would a catted X still get good results?

Tires are my list so I'll have to look into gears and a shift kit as well.

Thanks.

 

No a catted x pipe wil not gain as much. if you are going to do it and don't have to worry about emissions then you have to go with non-catted.

 

The reason I asked that is it's not his shop so he might not be able to mess around with the emissions test, I'll have to ask him about that.

I also heard that shift kits can mess up the trans. Is that true? Plus would the kit offer performance increases over the X-cal tunes I'm already running?

 

Do you have the programmer or just the chip?

If you don't have the programmer, get it. You can tune your own car at your leisure. A shift kit will let you shift harder and faster. IMO it's a better upgrade than a tune. For an auto, after doing the exhaust stuff, this would be my list of stuff to buy: Programmer, 3.55 or 4.10 gears (depends on preference), shift kit, s/c, then CAI and stuff that will work for the s/c.

What you might want to do as well, since you have the SOHC, find a 03/04 cobra in the junk yard and take the engine. Only probably would be you'd have to redo a good bit of your current mods, but that motor is a beast! It's also quite expensive, impractical, and time-consuming to do an engine swap. But I say it'd be worth it. Plus it'll be street legal and you wouldn't have to pay the cobra insurance rates!

But, personally, here will be my list of mods once I convince the wife I need them. Stinger or Magnapack cat back, l/t headers, o/r-x, vortech s/c, 4.10 gears, shift-kit, cai and other intake components. I'm not worrying about being street legal. Around here, as long as you're not speeding, they won't stop you. I am also thinking about getting new piston heads and rings, then do a few other things to the engine. I'll also be adding a roll cage, since I have a vert. I'm really fighting an uphill battle with my car, auto and a vert!

 

i'm talking about like the emission the state does like every 3 years. at least that is how it is in Illinois.

http://www.bmracing.com/index.php?id...cat=21&pid=224

check out this ^

 

Go Knight Go!

 

Pat you ever take your car to the track? if so what does she run with auto and vert?

 

Yup, I know. In PA it's done by private shops for the state and done every year. Years ago you could hook any car you wanted up for emissions to get around stuff like this but I think they caught onto that and now they have provisions built in to keep people from cheating.



DrunkenDragon713,

I got the X-Cal 2 from Doug with the tunes he set up for me programed in.

An engine swap would be a little too much for what I want to do to this car. I just want it to be a cruising car that can make respectable runs at the track on street nights. I have plans for a straight track car down the road a little bit but that will most likely be an old fox body, not this car.

 

my current stang is completly stock. i am going to start doing some mods soon.

 

A Plenum/TP switch doesnt require a new MAF sensor. I have a 70mm TB on my car right now, but Im still waiting for the $$$ for a plenum. The 75mm TB isnt optimum unless you're pulling in a lot of air (i.e. supercharger or internal engine work). The engine can only burn so much fuel/air in stock form, and a larger-than-necessary TB actually slows down the flow of air, hurting performance. If you go with the intake route, 70mm is all you need for now.

By the way, an excellent book for anyone looking to work on their car is "Mustang Builder's Guide 1994-2004" by Sean Hyland. It's about $25, and gives a really good basis for working a Mustang to any performance level. It goes over engine, exhaust, trans, rear, intake, tires, suspension, etc. Definitely a good read.

 

Just to add... I would do the upper intake plenum way before the throttle body. The stock 65mm will flow fine with the mods you have...its the upper intake plenum that is restrictive.

 

Yep, youre right. I bought the TB first because that's what i had the money for at the time. The 70mm TB and plenum are dependent on each other to optimize power. ive heard as high as 11 or 12 hp with a good aftermarket combo.

 

my list of mods i want to do is in this order if i continue doing bolt ons.

CAI, intake Plenum, tuner, SLP loudmouth catback, off-road x-pipe, Throttle body,

and i want to do a turbo kit.

 

I'm not sure you'll get 11-12 hp but it is a good mod combo none the less.

I highly recomend an SCT tune. With a 70mm tb,plenum,cai and exhaust, Doug tuned my car(prior to the blower) and I picked up an additional 18RWHP, and 33RWTQ!

 

Thanks for the help guys. I wasn't aware of the 75mm TB and plenum being too much so I might have made a mistake there. I imagine I will have to get new tune files for the X-cal once I do this upgrade to take full advantage of it.

Also, can the plenum be 75mm and just run a 70mm TB? having some issues finding a 70mm plenum online.