Mazdaspeed miata exhaust question
#7
If you can't tell, these guys think your idea is stupid.
To shine some light on the subject. If you do this with an unmodified wastegate on your stock IHI turbo, you will have uncontrollable boost creep and will probably break something from going way lean. That is also assuming you do not have any fuel/computer mods.
Yes you will make more hp.
Update your signature with what car you have and what you've got done to it.
To shine some light on the subject. If you do this with an unmodified wastegate on your stock IHI turbo, you will have uncontrollable boost creep and will probably break something from going way lean. That is also assuming you do not have any fuel/computer mods.
Yes you will make more hp.
Update your signature with what car you have and what you've got done to it.
#14
All your going to get is boost creep by doing this. Our turbo's have internally gated wastegates that when you add better flowing exhaust, they basically give you a big middle finger and boost creeps in higher rpms. This is bad, in case you didn't know. Since, the stock injectors in an msm really only flow up to 10psi. And that's really pushing it for that matter since the oem tune runs lean as heck in the first place.
I suggest you buy a flyin miata downpipe at least. I have a FM dp and a 2.5" pipe out the back and the car is LOUD. I ended up adding in a resonator to keep piece of mind. In any weather colder then 60 degrees I creep from 10psi to 12-13. Which if I were still running stock injectors would mean POP! Goes the weasel.
Last edited by Braineack; 01-22-2013 at 02:41 PM.
#15
Have fun getting that exhaust dumping right under your seat so it fries off your nuts so you can't procreate. I've noticed on more than one MSM, that a wide-open exhaust (Much like your anus) will result in resonance that will surely make your manifold-to-head nuts back off. The 3" is pointless. Get a 2.5" DP and mid-pipe. Use the stock muffler (by the time exhaust gases reach this far back, they've cooled down and contracted in size and will fit through the stock muffler just fine. You'll have a nice quite but "sporty" exhaust note that won't call the police. I did this to my friends MSM and there was no noticeable decrease in performance from the 2.5" tail section to the stock muffler....but now the car doesn't vibrate her ears to death nor do the damn manifold nuts come loose.
Last edited by shuiend; 01-22-2013 at 05:04 PM.
#16
amazing how a simple question can lead to burnt nuts and not being able to procreate. so no 3 inch exhaus cutoutt im guessing and no 3 inch turbo back exhaust (I can custom fabricate one). so 2.5 exhaust from the turbo back??? I dont really mind the loud and obnoxious noise, wake up the cows and neighbors. I just want the most hp without blowing a few rods lol
#18
I actually ran a 3inch exhaust on my MSM with stock injectors and ecu for about 8 months and no problems here. I know others have had problems and I know for a fact it is not the most ideal setup and it runs lean in areas but it can be done. I just changed to a MS2 with larger injectors and run 13psi with no problems either. My wastegate would creep to 11psi on just wastegate pressure (before I installed the MS2 I had an MBC and the stock boost cut at 10psi in place to keep safe) but now that it is controlled by ebc I have zero problems and steady boost to redline. I would just advise against a straight pipe. I run a resonator and a huge magnoflow muffler to avoid sounding like I am racing at 4000 rpms.