Heavy Metal Thunder

So I've been considering making some changes to my exhaust setup and since this is my first mustang I would like to get some advice from those of you have more experience than me.

I have an 07 GT and currently have stock manifolds, stock catted H, stock midpipe, and pypes muffler delete axlebacks. It may also be relevant to add that I have the Bama tunes for life deal from AM so I would re-tune after any changes.

What I want...

1) I want a gain in performance, but it doesn't have to be the maximum gain. In other words, I don't want to waste my money for zero gain or a loss but I won't be racing my car so a moderate gain without breaking the bank would be ideal.

2) I want an improvement in sound. I like loud, deep, throaty. That being said, I care about tone quality and don't want to sound like a farm truck.

What I DON'T want...

1) I don't want to lose my cats. I just want to re-tune to stock with my handheld before going to inspection. I also have no mufflers and I have heard that no cats AND no mufflers is a bad combination.

2) I can't afford long tubes.

These are some of the setups i'm considering but I have some questions about each that I hope people can answer for me.

Setup 1 - Short tubes, stock H, pypes muffler delete axleback.
- I noticed a definite loss in low end torque when I put the muffler deletes on, will adding the short tubes along with the deletes, give me a net loss or gain from my current setup?
- Can anyone describe what the change in sound would be from my current setup? I assume it would be louder but how much? How would the tone change? I know it depends largely on what headers I used, so any input specific to that would help too.

Setup 2 - Short tubes, stock H, chambered axleback.
- This would cost me a little more since I'd have to purchase a new axleback along with the headers. Therefore I would only go this route if it was the only way to regain the lost HP from losing the mufflers.
- How would this sound compared to my current setup with the stock manifolds and the deletes? Louder? Difference in tone?

Setup 3 - Short tubes, stock H, resonators welded into midpipe, pypes muffler delete.
- Would the resonators welded into the midpipe give me the hp back I lost when I got rid of my mufflers?
- Does anyone know if there would be any difference between my midpipe with resonators/muffler delete combo and the pypes mid muffler system?
- How would this compare performance and sound wise to the other 2 setups and my current setup.

I know there are a lot of questions here so thanks in advance to anyone who is willing to help me figure this all out.

HMT

Gtpony325

Well if you are considering shorty headers i have a set of bbk shortys that im not using anymore due to the fact that i switched to pypes long tubes. They are used and dont look spectacular but they do work. As for the change in sound with shortys it will change some but i cant really say how much. As far as gain in hp if you did just the headers and a tune you could be looking at maybe 10 hp tops. I kno i didnt really answer any of your questions but i thought you might be interested in shortys for cheap if you wanted to go that route

bob

That's odd losing power with the stock H-pipe still in place? I wouldn't think with the stock cats there would be enough over-scavenging to hurt power output?

Never ran my 07 with anything over than a chambered muffler though. If anything, I think adding a set up shorties would exasperate the problem.

05stangkc

I got a Question for you. Have you ever had somebody do a drive by in your car and listen from the outside? I remember thinking how puny my car sounded from inside while driving and then decided to hear what everybody else was hearing while outside. It was a whole nuther sound! Just a thought.

KC

Gtpony325

I went through 3 different exhaust set ups before i finally heard my car during a drive by. I cant believe how angry it sounds. The third and final set up ended up with pypes full length headers and catless x pipe with pypes violator mufflers. I have been told by numerous police officers that it is too loud but i have not yet recieved a ticket for it.

ETNOATS

But that would require someone else driving my car. Guess I will never know.

gmantheman

The best sounding axlebacks/exhaust are usually the other people. But I have heard other people drive my car and I am impressed by the sound of my exhaust.

avinaj80

I just recently changed to the Magnaflow 3" Magnapaks from the Flowmaster American Thunders and it sounds wicked... The magnapaks are a straight through muffler design and I guess thats how they get their aggressive sound.

I am about to throw a set of FRPP shorty headers, I can't afford longtubes, nor can I have em here (Cali). I know I am not going to get a whole lot of gain (maybe 3-5hp), but what I wan't out of them is the movement of the powerband, and extra tone it will produce. I know a lot of people knock the shorty headers, but they give more power/torque in the lower RPM ranges.

As far as more power? Without modding the engine, you won't really see much. I'd recommend some CMCV deletes and some under drive pulleys will egt you some more kick. With a propper tune, that'll be a kick *** combo for short cash.

ARSMITH25

Why can't you have L/T headers in Cali? If you have Cats on, isn't that which is all required?

DaTT(1sK)

I have a Bassani exhaust setup. Axle back, X-Pipe and Bassani Hi-Flo cats. I constantly get compliments on the sound.....constantly.

It is quite loud though. Expect to set off the odd car alarm.....and under WOT, it sounds amazing, even as the driver.

DynamicmustangGT

Actually L/T's are illegal almost everywhere. Once you change the stock location of the cats, which long tubes do then you are no longer in compliance. My Borla LT's even had a tag on them that warn people to be aware that long tubes are for off road use only. In CT all they do is a computer test they do not use mirrors to check that you actually have cats on the car and no longer do a sniffer test. From what I have heard Cali is much more strict on inspecting the exhaust system.

Gtpony325

Have you passed your emission test with your long tubes?? I have mine coming up and since i have installed my long tubes im throwing a code for o2 sensor slow response. And since i have no cats my rear o2 sensors are turned off so they will not register on the test which will also cause me to fail. In illionois it is only the computer test no mirrors and no sniffer. But i cant pass the computer test with my car the way it is.

avinaj80

I opted for shorties cuz I don't have the bank roll for the LT's. As far as your o2 sensor situation, the rears being off doesn't really matter. If your front o2's are triggering the MIL in California your not getting a smog test, not till the MIL is off. Dunno how it is in your state, but I think for most states if you got a MIL on, your automatically failed if your up for a test only...

Gtpony325

The front o2 i have new replacements for. Im just worried about how to tackle the situation of not having cats.

Everett

Well a tuner will shut off the rears. Just save your stock exhaust for inspection days. Pain in the *** but worth it

www.**********

Gtpony325

The rear o2s have already been turned off but the way the test works in illinois is the tester reads the catalyst reading. With the o2s off the catalyst doesnt read. Therefore i fail. I have all my stock exhaust but i dont want to take my headers off just to pass the test. The cats i can move an reweld in place and just swap the pipe. I might just turn my rear o2 sensors back on and use my mil eliminators and see where that gets me.

ETNOATS

I read that some tuners can adjust the time for the O2s to heat up, where did you get your tunes? Ask if they can redo since the cats are moved down stream further.

Gtpony325

Its actually my front o2 sensors that arent heating up properly. I will still ask them
If they can increase the heat up time. I know that there has to be someone out there that has passed emission tests with long tube headers

SONICBOOST

A catted prochamber will sound great!

ETNOATS

That Sir is ILLEGAL!!