Straight piped for power
 

Hey guys, currently I'm running non resonated test pipes , Topspeer 2.5 inch dual cat back, and my own shirt tails with those hemlotz resonators in them. Leo you think I am loosing any significant power ?? My car is a 2014 Nismo 370z btw

Why would you lose power?

No pressure in the bsck anymore

I removed th mufflers

Just changing the mufflers isn't gonna lose or gain you any power

Exactly! Why the hell
Do people keep insisting I am loosing power and torque from taking off my mufflers from my cat back

Do you know what your A/F is? With the muffler gone. You might be lean.

Agree.

I have no idea, but if I am, a tune would correct it? Btw what wre consequences of running lean

Don't worry about running lean. I put a custom dual with top speed axle backs and my Z screams. I even picked up 2-3mpg too. I'm at 22.5 on daily and 28 hwy. Go for it and you will be happy. There is a bit of drone tho.

They are insisting that you are losing low down torque due to the loss of back pressure from having no restrictions, such as cats, and a larger pipe diameter, which would increase flow. A tune would correct the A/F and bring some of that lost power back.

As for consequences, if you were really lean it could cause detonation and damage your engine. I doubt that's happening though. The ECU will compensate as much as it can.

When the ECU is in closed loop. It can adjust the A/F pretty close to where it needs to be, unless it is too far to the one side. Then you need a tune. At WOT, think you will need a tune to correct the A/F. As for engine damage. Agree, detonation, burnt exhaust valves, turn the tops of the pistons into silly putty, burn the ends of the spark plugs off, etc. Don't ask me how I know. :facepalm:

wow, so exactly how much power (hp and torque) am I really loosing from being straight piped on my nismo? even with a tune will I never have as good power output as with mufflers?

Hard to guess on power loss. The only way to know for sure is to dyno before and after. You lost a couple ponies, and some torque on top. How much, don't know. With a tune. You might be more then what you had before the mods. Don't know because you have no base line.

Probably not losing any power down low -- test pipes and exhaust delete are common mods that haven't shown losses to the best of my knowledge -- and you almost certainly gained a good bit up top.

Now, how the ECU has adjusted to these changes (especially without a tune to deal with the missing cats...) isn't clear.

Do you have a CEL (SES) light on?