Anyone have a setup similar to this??

[Blk04GT]

I have 5spd 2004 GT with a K&N cai and a Borla catback. Everything else is stock at this point. There are a few more things I was looking to do and need some input. Steeda udp, Accufab tb and plenum, 3.73 gears.

Couple of questions...

1. Do I need a timing adjuster with the pulleys?

2. Is there another brand tb/plenum I should consider?

3. What size tb to go with, 70mm or 75mm and why?

Any info would be great. Thanks!

[mrtstang]

1. No

2. No. The Accufab is as good as it gets.

3. 75mm. Leaves a liitle room to grow, and will work as good as the 70mm with just bolt ons.

Also i would do 3.90's or 4.10's, unless you plan on making 400 + hp.

[03muscle]

^^^^
+1

[Blk04GT]

I don't really see myself doing much more than what what was listed other than maybe a mid pipe, so I know i'll never come close to 400hp. Why 4.10's vs the 3.73's...and what are the stock gears in that year? I have heard 3.27 and 3.55.

Thanks.

[mrtstang]

The stock gears are a 3.27 in the 04 gt.

Basically, if you are just doing bolt on stuff you'll need all the torque manipulation you can get...hence 4.10's. The mod motors don't have great low end torque, and the 4.10's really complement the stock powerband nicely.

If you ever rode in a 99-04 gt with 3.73's and 4.10's, you'd understand why i recommend them.

They will really transform the way the car accelerates and feels.

[Swiss026]

I agree with mrtstang and second the point not to get 4.10s if a blower is in the future plans....

[Blk04GT]

How do the 4.10's affect daily driving vs. 3.73's (cause my wife drives this on occasion)? And is mpg difference between them even an issue?

Thanks again for all the input. I was hoping I would get some info from people who have done some of these different mods and it sounds like you all have!

[Swiss026]

Gas will go down with any of the gears you're talking about, but only because the RPMs will run higher - if you stay aware of that when you're driving it shouldn't be TOO noticable. I try to keep my RPMs down as best I can, but I have noticed a difference with my 3.73s.

As for daily driving - she'll only notice them if she puts it down. The car will have an easier time spinning the wheels on wet pavement, etc.

[mrtstang]

The mpg difference between the 2 is nothing to even worry about. You won't even notice it.

The 4.10's will be 200-300 rpm higher at any given point. The car will get in it's powerband faster and make it much more fun in general.

I agree with Swiss, she isn't going to notice a difference except in those certain circumstances.

[Blk04GT]

When the time comes that I do complete all this, how important is it that I have the car tuned. I am specifically wondering about after I change the tb/plenum. Will the cars computer just adjust for all these mods or will I also need to invest in a tuner for it run right?

[mrtstang]

With just the tb/plenum and pullies you won't need a tune. It will run better with one, but it's not absolutley necessary.

Now, if you do gears you'll need to adjust your speedo, and one of the functions of a hand held tuner is to do that very thing. You could also buy a speed cal adjuster, but i'd highly recommend the tuner, because you'll be killing 2 birds with one stone...know what i mean?

IMHO, i would forget the pullies and tb, and do gears, tune, and a mid pipe (and headers if possible). You'll gain much more from these mods.

[Blk04GT]

I see your point on the tuner. I have a couple more questions now about the throttle body and mid pipe...

1. If I replace my midpipe and am flowing air better shouldn't I still need to upgrade my tb/plenum or is the oem still efficent enough with adding the midpipe?

2. Is there a midpipe you would recommend that wouldn't make this car TOO much louder with the present catback?

[mrtstang]

I understand your logic, and it makes sense to a certain extent, but a tb/plenum is not as much of a bottleneck as the mid pipe. It will help a little, but not as much as the midpipe.

As far as what mid pipe to get? That depends on what kind of sound you're looking for. H pipes produce a lower, deeper, more rumbly sound. While x pipes are usually a little more smooth and higher pitched...in general of course.

Which ever you choose though, go catted if you don't want it really loud.

So basically any catted x or h will do.

[Blk04GT]

Which mid pipe, H or X, creates the popping and rasp on deceleration? I would prefer to avoid that.

[mrtstang]

In my experience the o/r h will be more raspy and poppy than than a o/r x. I've ran both before settling on a catted h. Since the Stingers and SSS are very similar in design (both straight through mufflers with a ceramic mesh insulated core) i would imagine you would get the same results.

[Swiss026]

I think the most rasp comes from a O/R X while the most popping comes from an O/R H. The cats will help with both sounds. I too am partial to the H over an X.

[mrtstang]

I think the most rasp comes from a O/R X while the most popping comes from an O/R H. The cats will help with both sounds. I too am partial to the H over an X.

There is some truth to that, but i can tell you personally that the o/r h had a much more rugged, mean, poppy/raspy, and just plain sloppy sound. The o/r x was much smoother and cleaner sounding. Despite that, i still liked the general tone of the h better. That's why i did a catted h.

I'm not sure how the stingers would respond, but being similar in design as the SSS, it would venture to say similar results would be likely.

My particular mufflers are louder than stingers (probably closer to SLP LM 1's from what i can tell) so it maybe more pronounced in my setup.

From what i've heard and seen the x pipes have more rasp and pop with the chambered mufflers in paticular. I'm sure there are exceptions, but this seems to be the general concensus.

[Ghost Rider]

Which mid pipe, H or X, creates the popping and rasp on deceleration? I would prefer to avoid that.

you'll be fine with either catted H or catted X...both pop though...it has nothing to do with the pipe...it's unburned fuel igniting in your exhaust that causes that. The stingers aren't overwhelmingly loud to begin with do to the baffling...so that will cut down on some of the noise cause by the igniting anyway. Also LT's help cut it down...but I wouldn't do LT's unless you are doing gears...cause you will lose some low end, which the gears make up for somewhat

[Blk04GT]

I don't know how much of a difference it makes, but I don't have the Stingers. I have the Borla cat back (model #14834). The only thing I know is that they're not supposed to be as aggressive as the stingers.

[Ghost Rider]

^^^ahh...okay, you'll be totally fine then bro :)

[mrtstang]

I don't know how much of a difference it makes, but I don't have the Stingers. I have the Borla cat back (model #14834). The only thing I know is that they're not supposed to be as aggressive as the stingers.

That was my bad...sorry! I saw Borla, and assumed you had stingers.

You still may get some rasp and pop from a o/r mid pipe, but it shouldn't be too bad.