Moddiction

Just curious what effects an exhaust leak has on performance. The place that bolted up my exhaust for me, didn't have gaskets and just used gasket maker. It looks like they just used it all around the outside of the flange. So I would think there must be an exhaust leak somewhere. If there is does that have any negative effects on performance or anything really? Hard to tell from listening since my exhaust is really loud, but one of the exhaust tips seems to have more air and sound coming from it. Does that sound like one of the connections is leaking along the line somewhere?

JmanS2k

it's hard to say by not being able to hear it, but if you do have a leak then you're probably losing backpressure.

iDomN8U

You should be able to feel it with your hand or a lighter. Narrow down the leak

Moddiction

How do you feel it with a lighter?
I am mostly wondering what the negative effects of an exhaust leak are. Will it rob power? Make the car run worse? What?

iDomN8U

take a lighter to where you suspect the exhaust leak and see if the flame is disturbed.

Granted the conditions in room need to be still.

The effects are a drop in pressure and therefore a decrease in savaging.

net result, loss of power

Moddiction

Do you know how significant the loss in power can be? Like can it max be like 2 hp or are we talking possibly much higher hp loss possibility?

jshimer23

I can't imagine anyone giving you an exact # as far as how much HP could be lost. It'd be hard to even give you a rough estimate. If you would loose any meassurable amount of HP from an exhaust leak, I would think it would have to be a pretty major leak. In that case, you should be able to hear it clearly.

As some one said, check the points where a gasket should be. Use a lighter or you could also spray some soapy water on the flanges to see if you get some bubbles.

Personally, gaskets aren't really all that expensive. I'd say get some and slap them on to give you the peace of mind.

Moddiction

Yeah I will be getting some gaskets, but have been having a tough time finding the ones that mate up between the stock cat or test pipe and then aftermarket cat back. I contacted Spugen since i have their exhaust and they never reply. Don't even know if they are still making any exhausts anymore.

negcamber

Here is a dyno showing the impact of exhaust leaks.

The black line is the car in healthy condition.

The red line is the same car that had been VAFC tuned (which should give more hp) but ended up having an exhaust that was falling apart from bad welds. Note: this is on the same dyno with nearly identical weather conditions.

iDomN8U

I'm shocked if a exhaust shop wouldn't have it