GWR header and midpipe, still stock muffler

Miata Parts, Intakes, Superchargers, Headers, Exhausts, Shocks, Springs, Sway Bars, Brake Kits, Autocross and track mods.
Post Reply
ourly
Posts: 101
Joined: Mon Apr 26, 2010 5:48 am

GWR header and midpipe, still stock muffler

Post by ourly »

Hello Brian,

Thanks for the header and midpipe, i'm digging the car. My question is whether or not the stock muffler is really backing up my header/midpipe? Do you think the dyno #ers you showed for your header/mid will be lowered with the stock muffler?

Thanks, Rick
Brian
Site Admin
Posts: 11308
Joined: Tue Feb 15, 2005 11:44 am
Location: San Diego CA
Contact:

Re: GWR header and midpipe, still stock muffler

Post by Brian »

Yes, the stock muffler is not designed for the flow you are getting from our 2.5 inch header and 2.5 inch midpipe. You will still get some benefit of the header but significant peak HP is being left on the table because that stock muffler is restrictive by comparison with the rest of the system. Take a look at the RoadsterSport Q....it was designed to handle the flow....while keeping the sound down.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
nate4bball
Posts: 1
Joined: Mon Jan 24, 2011 3:45 pm

Re: GWR header and midpipe, still stock muffler

Post by nate4bball »

Hi Brian,

I have a similar question about my current racing beat muffler which is 2.375 inches.
I plan on using the GWR headers and midpipe while keeping the racing beat muffler.
Do you think this will have a negative impact on potential hp gains?

Thanks,
Nathan
Brian
Site Admin
Posts: 11308
Joined: Tue Feb 15, 2005 11:44 am
Location: San Diego CA
Contact:

Re: GWR header and midpipe, still stock muffler

Post by Brian »

The 2.5 would be ideal....but very slightly smaller won't make much difference....perhaps a few hp at the very top of the rpms.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
Post Reply