Gutting Exhaust

[07 GT]

Does it hurt performance by gutting out the stock exhaust on a 07 Apex??

My cousin just gutted his and its sounds awesome. I was just wondering if there is any down sides to doing this. Will the sled run too lean???

I would like to do this to my sled it sounds so sweet!

 

[Indy]

I did it on my RX1 a couple of years ago, sounded sweet, no real notice in power. but at 70 MPH my teeth would rattle, no $hit, so I went back to stock.

 

[sandy8657]

I wouldn't!
It's the poor mans modification just for more noise!

With computers controlling and regulating intake and exhaust, tampering with the airbox or exhaust, might actually set you back in performance.

"just because it's loud, doesn't mean it's fast!"

 

[Tork]

trusted guys have dynoed the gutted exhaust a while back. I believe like 2 HP was lost (no gain in power but a loss)

 

[SharkAttak]

what the difference between gutting the exhaust and adding an after market exhaust, it seems the after market exhaust create h.p.

 

[bashley]

It's all about backpressure and flow. Gutting it will eliminate the backpressure the engine is tuned for. The aftermarket ones get rid of some but still keep enough while allowing the air to flow more directly.
Both of these can be compensated for with the right air/fuel mix. I just think it's too much money and time spent on too little of a gain.
I'd rather fill my tank up 20 times and ride the crap out of it than spend the money on a new exhaust, and definately don't need it any louder by gutting.

 

[SharkAttak]

It's all about backpressure and flow. Gutting it will eliminate the backpressure the engine is tuned for. The aftermarket ones get rid of some but still keep enough while allowing the air to flow more directly.
Both of these can be compensated for with the right air/fuel mix. I just think it's too much money and time spent on too little of a gain.
I'd rather fill my tank up 20 times and ride the crap out of it than spend the money on a new exhaust, and definately don't need it any louder by gutting.

i also agree, i would like to get more power out of my exhaust without the loud noise

 

[BigMac]

Internal combustions engines are really little than air pumps. And the more air they pump, the better, as long as the fuel corresponds in the right mixture to ignite as forcefully as possible. Anything you do to increase airflow through an engine will increase power as long as the amount of fuel that corresponds is correct. This includes everything from a lower restriction exhaust to gutting the airbox, to adding a blower. The fuel injection in our sleds is open loop. The lack of an O2 sensor means that the fuel system's capability of accomodating increased airflow is limited. It would probably be OK with a lower restriction exhaust, but may not add much performance until you also mod the airbox. If you do that, however, airflow through the engine is such that it is likely to exceed the EFI system's ability to accomodate and you'll need a different fuel map for your EFI...that's where PowerCommander III comes in.

 

[iasledder]

The real down side is NOISE. The more you make the sooner we can get more trails shut down. All of the supposed 2 and 3 hp gains is BS. Would dare you to know or find the difference. Those that say yes to gains are trying to make themselves feel better for wasting money. Just my opinions.

 

[Indy]

and don't forget the cost of repairing your teeth! Anyone who rode my sled said the same thing around the same MPH, but it did sound real cool. The best part was when we would actually get some snow in central Indiana and I would zoom down my street, all curtains would open. LOL