make sure you installed correctly. is there a leak at the header to the head? is o2 sensor plugged back in? any wires or connectors near the header get dislodged during install? when you modified air box did you unplug any connectors?

installing those parts would not make car behave that poorly. worst case you dont make power, but losing? the stock computer can learn to a point, so its not mandatory to tune after each mod. just helps get the most out of them. many manufactures, berk included, quote dyno numbers on stock cars with stock ecu.

good luck.

 

umm.. no. running lean creates power. when i was supercharged and even now NA. every time i get it tuned the tuner always goes for the lean. of course you do pose on thing right, if it is to lean you can cause detonation and damage to the engine. mods on an NA car are minimal enough the ECU can learn and YOU CAN MAKE power. There are plenty of people on here making power with factory ECU and have been doing so for quite some time including me.

 

[QUOTE=icemans2k02,Jul 7 2008, 08:26 AM] umm.. no.

 

i think the problem here is you need to define lean and define rich. both myself and my buddy made more power running richer then leaner at the dyno.

he has supercharged gsr motor and made more power at 11.5 to 1 then at 12:1. i also made more power at 12.3:1 then at 13:1. these numbers are from aem ems wideband readings at the collector of header.

you dont always make more power leaner

now if your car was 10:1 when he started, then yeah leaner would make more power becuase you started soooooo rich. again, you need to give a point of reference or else your statement has so substance.

 

Thank you!

 

this chart is the shiznit!





oh, my afr numbers i quoted for my car are for a NA car.

 

When most people tune they tend to err on the side of too much fuel, as this is not nearly as dangerous as running a car with too little fuel. This is the reason that when deviating from the average tune, leaner makes more power.

If the hypothetical optimal power is made at 13.0 afr, you'd be a moron to run 13.5 as you're losing power and damaging your car. On the other hand running a 12.5 afr is completely logical; it may not make optimal power but it is safer and cooler. With any decent, safe tune, leaner will make more power.

 

i know its not the end all source, but on wikipedia, theres a decent article about air fuel ratio.

http://en.wikipedia.org/wiki/Air_fuel_ratio

in the end, there is no magic number you make max power at. you need a dyno to find it. and then, be careful of which number you quote, becuase tail sniffer and wideband at collector will read two different numbers.

 

I followed the advice in the first response and did reset the ECU. I realize that a test drive is not scientific but until I can get time on a Dyno it has to do.

Low end throttle response is back. It is crisp. Before it would actually bog the engine down if I punched it.

Mid-range feels like it should. I got excellent acceleration from 3K up.

As always, VTEC is still a thrill. I made 8K shifts in the first four gears.

For now I feel like the car is running correctly again. I do plan to get a baseline dyno run soon. Then I will install the Berk exhaust and see what I get out of it.

Thanks for all of the interesting replies.

 

What would resetting the ECU do? The ECU is a learning ecu and learns and adjusts to any changes in air flow, temperature, pressure etc...

Ive seen lots of people lose power with the berk header, I didnt have a baseline run to compare with though.

If I were you I would take out the AUT plate and put the stock radiator plate back. It works just fine.

You might want to re-consider the berk exhaust and go with a T1R single. Berk sounds alot like invidia exhausts, very raspy and very loud. Tons of drone.