Exhaust Chamber Delete Question

Wronka

I have heard mixed views on whether this hinders back pressure or not. I am on a limited budget and have been doing little things to increase hp and sound. I took out the exhaust resinators and had straight pipe put in for sound and am going to get the cats replaced with non-resonated test pipes. I was also going to do an exhaust delete but I wanted to see what you guys think about this alteration. Thank you for your time.

RoshDawg

Do you mean muffler delete? If so, since you already have straight pipes at the cats, you will lose back pressure without the muffler. I have heard around that this is not so bad on NA cars, but you'll still risk losing a very slight amount of torque.
If someone knows more about this than me I would also really like to know.
Oh and wronka, if you are very short on funds look up what a washer mod is. Very cheap and will get you sound.
On second thought, do NOT do that as you removed your cats.

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canes7

Well.. It's been a long time since I was building engines and race cars... back in the carburateur days to be exact. Here is what I know about exhausts.

You want some backpressure. Lower backpressure usually results in moving the powerband up on the RPM scale. Not a bad idea for a track car but low end torque gets you off the line and around corners on the street.

What sounds good to your ears may not be good for horsepower. I can't think of any professional engine/car builder that builds to a sound. They all build for power. What makes power may not be compatable to your ears. You'll learn to like what you hear.

If you are oing to make major changes to your exhaust, make sure to step down the ID of the pipes once, maybe twice, from the collector all the way to the tailpipe. As exhaust gasses cool they constrict. To maintain exhaust gas velocity you'll want to match pipe ID to volume. This helps scavange the cylinder of burnt gasses when the exhaust valve opens and it also helps suck the intake charge in during valve overlap.

I'm not familiar with the VQ engines in these Z cars (yet), so I do not know if these rules still apply, but they are somethign to think about.

halogodx

I was running resonated test pipes and the washer mod for a week or two. Other than the super loud sound, the exhaust gases leaking into the cabin were the same amount as with no washer mod.