AFR vs valve float question
Thread Starter
Staging Lane
Joined: Jul 2013
Posts: 73
Likes: 0
AFR vs valve float question I had a incident at the track where I lost some boost and made a 10% change to the boost controller duty cycle to try and compensate. when it did not make an increase in boost I noticed the top waste gate fitting was loose so I tightened it and made another pass without going back on the boost controller duty cycle.
I over shot my target boost by 4 psi and the car did not pull as good as I think it should. my AFR went up to high 12's but my injector duty cycle went down a bunch.
I am thinking that I got into a valve float issue and that caused the weird increase in AFR with a reduction in injector duty cycle.
would this be correct?
I over shot my target boost by 4 psi and the car did not pull as good as I think it should. my AFR went up to high 12's but my injector duty cycle went down a bunch.
I am thinking that I got into a valve float issue and that caused the weird increase in AFR with a reduction in injector duty cycle.
would this be correct?
9 Second Club
Joined: Nov 2003
Posts: 13,616
Likes: 185
From: Norn Iron
Valve float will skew AFR readings...in what way would depend how bad.
And what ecu are you using ? You seem to be implying you are allowing the ecu to make large corrections based on AFR seen....which can be risky.
4psi isnt a huge overshoot anyway, and tuning should easily accommodate such things.
And what ecu are you using ? You seem to be implying you are allowing the ecu to make large corrections based on AFR seen....which can be risky.
4psi isnt a huge overshoot anyway, and tuning should easily accommodate such things.
do you have aftermarket springs?
I was fine at 15psi but when i jump to 18-20psi the car experienced valve float.
after installation of some dual springs it pulled all the way till redline instead of what feels like running out of steam.
I was fine at 15psi but when i jump to 18-20psi the car experienced valve float.
after installation of some dual springs it pulled all the way till redline instead of what feels like running out of steam.
