I am asking for a friend who just bought a IX RS and is very interrested in buying the 3.5'' APS (TBE) and wants to know what kind of modification does he have to do in order to make it fit. Also, does anybody have any sound clips of the APS 3.5" (TBE) and have a dyno chart of just having the APS 3.5"(TBE) on? I would greatly appreciate your inputs.

 

you should never lose top end power with a larger exhaust, you might lose some low end though.

 

Top end should be absolutely fine, and i wouldn't imagine your low end would be effected that much. The turbo should supply decent back pressure.

I have a friend with the 3.5" APS on a SR55'd STI, holy ***** is this an awesome system. Sound is PERFECT in the cabin (barely noticable at all, seriously) and fine under daily driving from behind. But when its romped on, holy mother of god.

 

The 3.5" APS system hits the inside of the rear diffuser on the JDM/Euro spec cars (wont fit), i dont know if the US rear bumpers are the same on the IX?
You can make them fit but the bumper has to be cut

 

Come on now! Somebody has to know in this big community!

 

I don't see why you would want a 3.5" unless you're making some pretty big power. Ditto on the low power.

 

It will make little difference, the exhaust is only as good as its smallest restriction, the Turbo elbow to downpipe on the Evo is 2.25"

 

3.5 in exhaust should only be used on garret GT35r turbos and up.

 

Wrong wrong wrong! You dont need a 3.5 for only a gt35 and up..... If anything, you will gain power on the top end. Low end may be slightly less than before though. Think of this... the larger the exhaust is, the more air the turbo can get rid of, less back pressure, more flow...... Now if you had an NA car, then back pressure is needed to have the right balance in power.

also, MGAUTOS, how is your statement true? Are you saying that putting a 3" turbo back on a stock evo wont give it more hp??? I dont agree with that.

 

Gains aside, the 3.5" sounds like ***.

I would never advise someone to get a 3.5" on stock turbo, in fact I dealt with this same question this week.

 

When i questioned martin at ams i was also told there was no reason for a exhaust that large until you get into the bigger turbos. you wont see any real gain especially if you have a 3" tbe with no cat. The outlet on our stock turbo manifolds is only so big the 3" is plenty big for that not worth the extra money unless you think your going to be gettin a gt42r or something in the future

 

so wat is the best size and tbe set up?

 

A larger diameter exhaust will not compromise low speed performance on a turbo car. Obviously this does not apply to a normally aspirated car, which has very different exhaust requirements. Do not confuse the two. Also, backpressure never did anything but reduce power. The reasons why a smaller exhaust improves low speed performance typically have nothing to do with backpressure (a common misconception).

On the other hand, a 3.5" system will not deliver any more power than a 3" system if the 3" system does not pose sufficient restriction to compromise power. This is a wee dose of reality for the 'bigger must be better' crowd.

 

i have the hks cf ti exhaust(not a tru 3) wat do u think is the best dp?n if its a 3 would it hurt to have it neck down(being that the exhaust is 2.9)?

 

Does anybody have one on their evo IX or VIII (05'
+) perhaps?