2.25" vs. 2.5" exhaust

it'll be fine

i'm making 442 with weld in's, if that helps you any

You will gain another 15 or so from a catback Stangman.
But you have those VT STG1 cams...thats why power comes easy to you with only 8PSI.

Stock cobras have 2.5 inch pipe...upgrading to mandrel bent 2.5 ith better mufflers gain them around 25RWHP. (03-04 cobra with just a catback...400RWHP, thats is the best iv heard so far. Stock is around 365.)


Go 2.5 or dont bother....it will just cost you power for nothing.
2.5>2.25 if its a stock GT or a 600RWHP monster.

It will be fine for now

^Yea by the time you buy mufflers and weld them in, you pay over $200 and gain MAYBE 1HP.

You can even buy a magnaflow catback off of partshopper with code MAGNA454 and get it for $350.

After I when with 2.5" exhaust piping on my mustang I notest
that I lost a very small amount of low end torque but, I seemed
to gain it all back and more on the top end.These cars seem to
react different to exhaust mods than turbocharged Subaru's do.
I must say I love my exhaust note with the Magnapack.
Fresh popcorn anyone?

^Thats until you turbo them

Turbo cars like ZERO back pressure...the less the better. Thats why alot of guys run cutouts just after the turbo.

hotmustang331 said:

^Thats until you turbo them

Turbo cars like ZERO back pressure...the less the better. Thats why alot of guys run cutouts just after the turbo.

Click to expand...

Yep,I agree with that statement lol.
How is the progress coming with your turbo install on your mustang?

Pennywise2 said:

Yep,I agree with that statement lol.
How is the progress coming with your turbo install on your mustang?

Click to expand...

IT stopped cuz he drove down to Houston and gave me all of the parts for the whole turbo build. Can you believe how nice this guy is? I was shocked to say the least and all for free!

....WAKE UP GILDED GELDING...I think you dosed off there for a second . Im a nice guy....but err not quite that nice AHAHAHA.


But seriously, we are about 95% done with it...got the IC back from a guy we know today (Tig welded the relocated clamp lips on and sealed the 2 holes we made by having to do that) and mounted it. Really its all down hill from now.

Im waiting on the following for 100%

A. cut and paint hood, and reinstall (may be done after car is running)
B. Weld and do some minor fixing on the headers W/ pressure testing
C. 15 mins of welding on the up pipe
D. finish up fabbing the wastegate mounting on one side
E. small amount of wiring, which ill do tommorow (- solenoid im waiting on)
F. Freegin pro turbo kits jipped me of one 4-3.5 coupler, so I cant mount the MAF. Waiting on it.
G. Silicon hose place JUST ran out of black 6MM hose....waiting on that
H. Route oil pressure/return lines
I. Mount air filters when they arrive
J. fab up 3 pieces of short pipe to finish off cold side
K. Get the welder to tig the BOV flange on the aluminum pipe (tomorrow)
L. Place all gaskets and bolt everything down finnally.

This later stuff isnt required to drive the car...ill break in the clutch and then do the following.

M. Install fuel pump
N. Hook up fuel pressure gauge when it comes in (custom speed hut)
O. Drive 15 hours one way swap in the 42# injectors when we get to MPH and have Tim tune it

There are some small things like making 3 brackets for relocating the water coolant/fill basket, and make a little bracket for the relocated power steering fill basket.

This sounds like ALOT...but really its NOT. It wont take us very long lol. Car should be running sometime next week. Yea thats just 5% left to do....now you guys can see what we went through . BUNCH of time and a BUNCH of money

Sounds like you are making progress but,you have your
work cut out for you I agree.Welding your uppipe could
possibly be a PITB.I have been working on and installing
custom turbo kits on Subaru's for ten years now but, never
installed one on a mustang before.From what I hear Tims'
tunes are very safe.
The best of luck with your install though.

Thanks bud .

Yea the part we have to weld up will be pretty easy....we have to take everything off (up pipe/down pipe/headers) anyways to sand blast and spray high heat paint with ceremic on the pipes. I was going to send it out...but want to see how this 1200* ceremic paint does and to check durrability of all the welds. Would suck spending $500 on ceremic for it to just spring a leak .

Definatly would like to see some of your work, post some pics up here or PM me. Sounds like you really know what your doing

i dont know if this is true or not but the guy at the exhust shop i got my flows welded in at told me that you would lose hp is you have 2.5 inch catback if you dont have 300 or more hp. think he didnt wanna do it on my car or something