Need to figure this out. Info from Dyno runs and track runs

Dec 04. on the Dyno

Max MAF reading in 3rd gear at 5500 rpm ... 471 ... maxed out
the IAT was 108 degrees. O2 sensor readings on both sides were middle 800's Made 525 HP at the wheels

Apr 04, track test

Max MAF reading in 2nd gear at 5800 rpm ... 471 ... maxed out
the IAT was 104 degrees. O2 sensor readings on both sides were middle 800's


Jun 04, track test

Max MAF reading in 2nd gear at 5900 rpm ... 471 ... maxed out
the IAT was 108 degrees. O2 sensor readings on right side was middle 800's the left side definitely lower than the right and had a value of 9 as a low.


July 04, dyno ... no data but it made 559 hp at the wheels and the A/F ratio was pretty good at 12.5:1 on the top end, 6300 rpm


July 04, track test

Max MAF reading in 2nd gear at 6200 rpm ... 471 ... maxed out
the IAT was 130 degrees. O2 sensor readings on right side was middle 800's the left side definitely lower than the right and had a value of 9 as a low. The left side was showing a lot of 200mv readings. No recorded Knock retard at all. I run good gas ...


So, in a nut shell, I seem to have lost some air flow, though temperature may be a factor and I've definitely lost something on the left side of the engine ... O2 sensor going bad??

Any thoughts??

Is this how O2 sensors act as they die??

BTW, I managed a 116mph 1/4 at 12.5 seconds ... very slippery, but a reasonable mph for the altitude 3,600' and weight, 3850 lbs race weight.

thx

LWM

 

I've noticed when you push 42# injectors to the max, like your doing, and couple that with a Maxed MAF, the AF does weird and non-repeatable things. I noticed that last year doing some tuning on the dyno. Once the MAF is maxed and your trying to add fuel with the PE table, the injectors don't like it. I was having weird rich spikes, then a lean spike at upper rpms on back to back runs. Time for bigger injectors maybe? BTW my MAF was maxing out around 4700 Rpm.

 

thx for the reply SMOKNZ

I think my altitude has a lot to do with the MAF not being maxed out as early as in your case. The car does have a lot more get up and go than it did when it dynod 430 hp. Up here in Calgary Alberta I'm thinking there is quite a bit of correction factor at the dyno.

Seems kinda wierd to me also, I am adding 12% fuel in the PE table from 5200 rpm on up to 18% at 6000rpm. Mostly just to keep it rich enough to be safe.

I did succeed in moving up the right side O2mv to low 900s and the like, but the left side did not respond.

Any recommendations on injectors?? I'm still partial to the high impedance injectors so I can continue with the stock PCM and LT1 editor.

thx

LWM

 

i cant offer any experienced advice on the topic, but if you are looking to go up on injectors, i have some brand new hi-imp 57lb flow matched injectors for sale. http://web.camaross.com/forums/showt...hreadid=278721

 

I thought I saw a post on some 72# high impeadance injectors??? Might wanna do a search.

Bill

 

Update

2 new Bosch O2 sensors and a repaired collector leak.

Both sides are even and in the low 900's

Just thoughts I'd finish to saga

LWM