M90 supercharged 05 gt - need highflow - suggestion?

[06monera96]

Hey everyone,

My 05 just got an M90 installed on it. (10lbs boost)
Amazing, feels great.
Only issues is , I fear my cats may just blow right out the back soon.

Looking to replace them with some high flows.

Should I purchase some highflow cats and weld it in?(someone said not possible)

Or is there an H pipe with the high flows already welded on that I can purchase?

All resource is appreciated.

Thank you,

 

[07 Boss]

Is the exhaust stock?

 

[skwerl]

Stock cats are fine with the M90. And I highly doubt you're pushing 10 lbs of boost. I ran a 2.49" pulley on mine and made 8.5 lbs and you can't get a smaller pulley.

I highly suggest you monitor your IAT. The computer will pull timing at 135 degrees.

 

[joedls]

Stock cats are fine with the M90. And I highly doubt you're pushing 10 lbs of boost. I ran a 2.49" pulley on mine and made 8.5 lbs and you can't get a smaller pulley.

I highly suggest you monitor your IAT. The computer will pull timing at 135 degrees.

Could be 10 psi if his cats are already clogged.

 

[06monera96]

Stock cats are fine with the M90. And I highly doubt you're pushing 10 lbs of boost. I ran a 2.49" pulley on mine and made 8.5 lbs and you can't get a smaller pulley.

I highly suggest you monitor your IAT. The computer will pull timing at 135 degrees.

Hey Skwerl, we actually hit 9lbs 9 1/2lbs and a few glimpse of 10lbs(may be error reading from roush gauge, who knows) during dyno.
Yes it a 2.49" pulley.

We have obtained 9lbs during the entire 4th gear pull.

IAT is hovering 120, at WOT it goes down to 110 ish.


And yes to the question above, stock exhaust with Outlaws out the rear.
https://www.youtube.com/watch?v=_jn7ZAS6HWY
https://www.youtube.com/watch?v=aRx4_7OeRKA

 

[skwerl]

Awesome. I miss the whine of my M90.

 

[05stroker]

Are you making these dyno pulls in the A/C? Get ready for 180 deg in the real world. What is the rest of the setup? M90 with AIT falling, I assume you are spaying it?

 

[stkjock]

Stock cats > after market

/thread

 

[05stroker]

Stock cats > after market

/thread

Sorry I missed the meaning of the thread. No aftermarket cats ever!

 

[redfirepearlgt]

You're more than likely fine on the stock cats IF they are in good condition. Inspect them externally for heavy purple or dark discoloration at the entry of one or both. This will be a sign that they are restricting or beginning to restrict. There are after markets that you could have cut in place. AM sells some if I am not mistaken that can be welded in on 50-09 setups. I've run my last three cars with cats. Just keep an eye on them and watch for the signs.

High flows can fail as well. Off road midpipe is an option and can sound nice with the right (without droning your brains out in the car) exhaust config.

 

[JeremyH]

Could be 10 psi if his cats are already clogged.

lol


I agree 10psi and 110-120 iat seems like a stretch to me... above 6-7psi and the m90 starts making a lot more heat. Maybe perfect weather/temp conditions at the dyno or a generous gauge.

As for cats, I'm jaded from previous experiences but cats and boost is always a no no for me. I do agree stock is better over aftermarket or highflow versions.

 

[NickD87]

I got both... let me know what the consensus is. The aftermarket will be louder, I have heard stock are better for boost as well but I'm sure the magnaflows are high quality vs pypes.

 

[808muscle]

After market ceramic ones will melt. Dont get those. Keep the stockers.

 

[redfirepearlgt]

I got both... let me know what the consensus is. The aftermarket will be louder, I have heard stock are better for boost as well but I'm sure the magnaflows are high quality vs pypes.

Magnaflow makes good quality stuff. But make sure as stated they are not using ceramic vs metallic internals. Loved their tone on my 05 when it was complete the street series with LT's and O/R.

 

[06monera96]

So for those who anted to know

On idle normal 20-25c degree day IAT is 120F
Cruising on the highway not in boost 110F

Idling on a 30-35 degree day after a long highway pull 140F-150F

Last night it did not go past 110-115F

Like last night I did a good 5 gear pull off onto the highway and it stayed just around 105 after the pull and idled at 120F at a red light.