Lack of power above 5000RPMs..
 

Hey guys, I just got my new engine broken in and it pulls really good all the way up to 5000RPMs. from 5000 to 6000 it sputters a bit, either way i feel more "pull" at 4500 then any other RPM..

Could this be a ignition misfire problem??

Thanks for any help..

stock ports?

Racing beat based street port.

secondaries?

Car details? You didn't really give any information.

What engine management?

Do you have a wideband? If so, what mixtures are you seeing when it hesitates?

13BT S5, Street Port, 650 primarys, 1680cc secondaries, haltech E6X, Tuned it myself under boost it runs low 11:1 AFR.

When I lean it out it does make more power, But now where near what it should be..

The engine I built before this one had way more pull.. the only thing different on this engine is a bigger turbo, a different used leading coil pak, and bigger secondary fuel injectors.

I thought it might be the injectors but my air to fuel ratios are dialed in..

Im even running the same maps on the ecu.. exept I have set the secoundary injector drivers to 8 amps for the low impedance injectors and of course lean out the the fuel map for the larger injectors..