What i know is that the bigger the exhaust, the more power you get for decreasing backpreasure . But the problem is as you increase the diameter of your exhaust the sound becomes really loud and annoying.

So, i just had this idea and would like to discuss it. What if i used sound deadening barriers like the one offered by ThermoTech and wrap it aroung a 5" exhaust . It protect against excessive heat and noise. The only problem that i can think of is that the exhaust gases will be really hot .

So, what is the problem with high EGT?
And does this idea sound reasonable?

 

I like the idea of sound deadening but 5" exaust is overkill. 3" is ideal for anything around the stock turbo size.

 

some backpressure is actually a good thing. Without it, you'll get boost creep. Also, how the hell are you going to clear the damn sub frame connectors?


And I swear if I ever see an Evo driving on the street with a 5 inch exhaust, I'll shoot the driver.

 

max should be about 4 inches on an evo....
I went three inch but now I need to go bigger..I'm not even goin 4...may go 3.5

 

I'll help.

 

5" would be a little overkill on an evo, al dosent even run a 5" exhaust and hes and he is in the 9's

 

I have a 4" and it perfectly fine, you can feel the difference in the power and the sound

 

ok then, forget about the 5". but what do you think about wraping it?

 

Wrapping is good. Only egt near the manifold is important to engine conditions. High egt in the exhaust part means the exhaust is retaining the heat allowing it to escape faster. Seriously some 1000hp+ supras are running 4 inch exhausts.