New Perrin exhaust - lost torque

[Last Lemming Alive]

Originally Posted by DarkSunrise

Could it be that you're not yet used to the increase in sound at part throttle?

In other words, it's now much louder under load without any corresponding increase in speed, tricking you into thinking the car has gotten slower.

The reason I say this is I've got the 2.5" Perrin and didn't notice any loss in low-end torque, but it is definitely much louder under load.

Let me explain what's exactly happening: I start to accelerate normally, the engine gets to 2000 rpm and then it's like the fuel cuts for an instant, the engine falls flat on its face and then it picks back up and gets going. I've tried modulating the throttle to no avail. It's like the fuel map isn't keeping up. That is just what it feels like. You could also say it feels like a bog of the engine at 2000 rpm.

The only way I am able to overcome it is to launch off the line and make sure the rpm don't fall to 2k. Btw, the car has 2400 miles on it.

[Xxyion]

Originally Posted by Last Lemming Alive

Let me explain what's exactly happening: I start to accelerate normally, the engine gets to 2000 rpm and then it's like the fuel cuts for an instant, the engine falls flat on its face and then it picks back up and gets going. I've tried modulating the throttle to no avail. It's like the fuel map isn't keeping up. That is just what it feels like. You could also say it feels like a bog of the engine at 2000 rpm.

The only way I am able to overcome it is to launch off the line and make sure the rpm don't fall to 2k. Btw, the car has 2400 miles on it.

Interesting. Almost sounds like you are hitting the torque dip extremley early. Torque dip suually shows up at like 3500 RPM. However the new 17 MY torque dip while smaller, is also drastically deeper. I didnt really notice the torque dip on my 16 but when i test drove a 17 it was super obvious

[modbus]

I have the Perrin 2.5" resonated. I went to it after about 5k miles on the car. I put the stock back on for a while and it "felt" faster than I remember.

I'm going to guess that my perception of "loud = fast" was leading me to believe the car was faster when the stock catback is attached vs. when I had my catback.

The mind is a powerful thing... and can lead you to the wrong conclusions if real instruments to measure are not used.

[wparsons]

Originally Posted by Last Lemming Alive

Let me explain what's exactly happening: I start to accelerate normally, the engine gets to 2000 rpm and then it's like the fuel cuts for an instant, the engine falls flat on its face and then it picks back up and gets going. I've tried modulating the throttle to no avail. It's like the fuel map isn't keeping up. That is just what it feels like. You could also say it feels like a bog of the engine at 2000 rpm.

The only way I am able to overcome it is to launch off the line and make sure the rpm don't fall to 2k. Btw, the car has 2400 miles on it.

There's simply no way a cat-back alone is doing that unless you've got something totally blocking it like a piece of plastic or packaging.

[nikitopo]

I wouldn't believe a lot their dyno graphs. Most legal catbacks cannot increase power. If you had any gains, the noise would be so much that it would not pass any regulations. Your only chance to get any gains is if you install a competition exhaust.

[wparsons]

Originally Posted by nikitopo

I wouldn't believe a lot their dyno graphs. Most legal catbacks cannot increase power. If you had any gains, the noise would be so much that it would not pass any regulations. Your only chance to get any gains is if you install a competition exhaust.

That's simply not true. See the thread on the ACE Laguna Seca exhaust.

[Icecreamtruk]

Originally Posted by wparsons

That's simply not true. See the thread on the ACE Laguna Seca exhaust.

That exhaust doesnt gain you power, it just doesnt take power (or little) and reduces sound.

[wparsons]

Originally Posted by Icecreamtruk

That exhaust doesnt gain you power, it just doesnt take power (or little) and reduces sound.

Compared to what? It makes more power than stock and isn't as loud as other exhausts with comparable gains.

[Scrappydoo]

Originally Posted by Last Lemming Alive

I reinstalled the OEM exhaust tonite, and even without unplugging it the torque was back. It feels like 7-10 ft lbs was gained.

Perhaps this is your answer and your solution.

[Lynxis]

Originally Posted by Last Lemming Alive

Let me explain what's exactly happening: I start to accelerate normally, the engine gets to 2000 rpm and then it's like the fuel cuts for an instant, the engine falls flat on its face and then it picks back up and gets going. I've tried modulating the throttle to no avail. It's like the fuel map isn't keeping up. That is just what it feels like. You could also say it feels like a bog of the engine at 2000 rpm.

The only way I am able to overcome it is to launch off the line and make sure the rpm don't fall to 2k. Btw, the car has 2400 miles on it.

Based on this, I'd be concerned about an exhaust leak with the Perrin.

[86geek]

Instead of guessing why not contact Perrin....just my two cents

[nikitopo]

Originally Posted by wparsons

That's simply not true. See the thread on the ACE Laguna Seca exhaust.

Originally Posted by Icecreamtruk

That exhaust doesnt gain you power, it just doesnt take power (or little) and reduces sound.

That's what it says here: http://counterspacegarage.com/ace-cs...na90-gt86.html

"CSG commissioned a project with ACE to provide a Laguna Seca legal exhaust that emits an output of under 90dB without considerable loss of power or response. "

Anyway, I would never install a Taiwanese exhaust in my car. Personal preference. Sorry.

[humfrz]

Originally Posted by nikitopo

I wouldn't believe a lot their dyno graphs. Most legal catbacks cannot increase power. If you had any gains, the noise would be so much that it would not pass any regulations. Your only chance to get any gains is if you install a competition exhaust.

Yep, my take is that if you do enough dyno pulls, on enough dyno machines, you can generate enough graphs to show almost anything ........ just pick one ......


humfrz

[Icecreamtruk]

Originally Posted by wparsons

Compared to what? It makes more power than stock and isn't as loud as other exhausts with comparable gains.

Why dont you ask them that? Where do you see it makes more power than stock and has comparable gains? Comparable to what?

See, two can play this game. The ACE Laguna 90 is an exhaust for really low sound output, nothing more, nothing less.