04 bolt-ons

**travj31** · 07-31-2007, 02:46 PM

i'm sure this has been discussed before but just want some different opinions on this issue...

i have basically a stock 04 gt with a 5spd. i want to change the gears and i'm not sure what i should go with. i'm leaning towards 3:70's over 4:10's but just thought id see what you guys think. this car will never be a race car and will only have limited bolt-ons. if anyone has 3:70's in a rather stock 99-04, i'd love to hear what you have to say (positive or negative).

also what exhaust gives the best sound and performance... I love the slp loudmouth sound but does it give you comparable performance to a flowmaster or etc...?

promise this is the last one... what is the best over-all cold-air kit. want something that is easy to install that doesn't requiring drilling and so forth and also that gives the best performance gains.

any other "minor" bolt-on suggestions for the 99-04's is appreciated... throttle body, tunes, etc...

thanks!

**BoneCrusher** · 07-31-2007, 02:58 PM

I'd go with whatever exhaust sounds best to you they're all going to be pretty much the same for HP gains.
The K&N cold air kit is a great performer that is easy to install and holds it's own with any other intake.
Maybe do your pullies while you're at it.

As for the gears I'll vote for the 4.10's

**Slow01GT** · 07-31-2007, 03:19 PM

I will also give my vote to 4.10 gears. I would also suggest a new mid-pipe to complement any catback you get since the factory h-pipe is very restrictive.

**Cam99** · 07-31-2007, 04:01 PM

4.10s without a doubt. Flowmasters don't have great flow numbers (ironic), so let your budget be your guide. I had Mac on my 99 GT and loved the sound and price, but it never fit perfect no matter how much I adjusted it and it had alot of drone inside. The slp on the mach is top notch fit and finish, but not the cheapest out there. I like the K&N cai. Not a big fan of cai's made of metal, just seems like a good way to heat soak to me. Upper intake and throttle body aren't bad for the price. Longtubes are a nice upgrade but will require a tune .

**travj31** · 07-31-2007, 04:20 PM

what kind of rpm's are you turning with 4:10's or 3:70's at 65/70mph? with 4:10 's do you lose driveability on longer cruises?

**Slow01GT** · 07-31-2007, 05:27 PM

With my auto i'm at about 2800rpm at 70 in 4th. It should be similar for your 5spd in 5th. I drive 40+ highway miles everyday and make a lot of trips to ohio to race and i don't feel driveability has suffered at all.

**stieny** · 08-01-2007, 02:50 AM

I had Bassani cat'd x and cat back on my old GT and loved the sound. Not the cheapest but fit was perfect and sounded awesome IMO. But like it was stated earlier, they're all going to perform about the same so pick on that fits your budget and sound preference.

If you want a simple yet effective CAI kit I too would opt for a K&N kit. Easy to install and performs well.

4.10's are a must. Had them in mine and would do it again if I had another.

I had an accufab TB and plenum and liked it. Seemed to do good. If you hit up some other mustang sights you can find some good deals on some used quality stuff. Not a big fan of BBK or MAC stuff.

Edit: Another bang for your buck would be a short throw. Loved mine and made shifting like night and day. I had a steeda tri-ax and loved it. Pro 5.0 is another decent one.