Power loss with no exhaust?

[JamesE30]

So I put my long tube extractors on the other day, but unfortunately they do not bolt straight up to the 323i pipes.. So I'll be taking them to a shop for a bit of cutting and welding.
I've driven the car a couple of times with just the extractors, only a meter and a half in length (max), does it make sense that my m20 should loose power without the rest of the exhaust?
I don't want to go all the way to the shop and have my original pipes attached to these headers only to find that I've lost power..

Please tell me there is light at the end of the tunnel, and once I have my full system back on I will have gained power not lost it.. pleeease...

[kronus]

Yes, you can get worse performance with open headers on an engine that's tuned to have an exhaust system installed. Your ECU gets confused when stuff changes.

[Madhatter]

you'll find it has increased top end but the bottom end torque will suffer. There is a specific reason for it, but to make it simple, the reduced back pressure actually sees the motor suffer in the low to mid range.

Unless you have increased the diameter of the pipe in the rest of the system, you'll have the torque back when you get it all fitted back up. Thats what you'll feel as a lack of horsepower.

With mine fitted and the pipe diameter increased I still noticed a lack of low down torque, but top end really increased. I grabbed an extra 15km/h at the top.

Unless he has fitted a different ecu/injection system, the 323i unit doesnt run an o2 sensor, so it doesnt really have a problem with changes. Get the exhaust modified, im positive you will see the results you are looking for (as long as you dont expect 20hp increases on a stock engine).