Why am I running so lean?
Safety Car
Joined: Jun 2005
Posts: 4,977
Likes: 256
From: St. Louis Missouri
...
There is a table called Power Enrichment that is used for telling the O/S what AFR to run while at WOT. The correct way to do this is to set the desired AFR in this table and then tune your maf table so the AFR that is being spit out corresponds to the AFR you set in the PE table.
...
There is a table called Power Enrichment that is used for telling the O/S what AFR to run while at WOT. The correct way to do this is to set the desired AFR in this table and then tune your maf table so the AFR that is being spit out corresponds to the AFR you set in the PE table.
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Drifting
Joined: Apr 2009
Posts: 1,898
Likes: 9
From: Morrisville PA
Can't say I agree. MAF and VE should be dialed in on the street during normal driving conditions. Both are used during partial throttle to reach stoich. Adjusting one without the other is a worse hack than setting the PE table to inaccurate values (but reaching the desired AFR). Both of them are the wrong ways, but the latter is the lessor of two evils, in my opinion.
Of course you dial in the VE/Maf part throttle but what does that have to do with what I said regarding PE and Maf in terms of WOT fueling?
Safety Car
Joined: Jun 2005
Posts: 4,977
Likes: 256
From: St. Louis Missouri
You clearly stated that you should change the MAF table until the actual AFR matches the commanded AFR in PE. That is not how to properly calibrate the MAF table, as it will also have an affect on transient fuel calculations under normal driving.
Drifting
Joined: Apr 2009
Posts: 1,898
Likes: 9
From: Morrisville PA
It is absolutely the proper way to calibrate the high frequency (wot) cells by using lambda error. You set your PE to your desired AFR and dial in your maf table until your error is 0%, or as close to 0% as possible.
You do the same for the lower frequencies (part throttle), although PE may or may not come into play at that point. But that does not matter if you are tuning based off lambda error. After all, it is just commanded lambda vs actual lambda.
I gave a simplistic explanation because the OP has never tuned a car. It was fairly obvious we were talking about WOT only in this thread considering the thread title and attached dyno graph.
You do the same for the lower frequencies (part throttle), although PE may or may not come into play at that point. But that does not matter if you are tuning based off lambda error. After all, it is just commanded lambda vs actual lambda.
I gave a simplistic explanation because the OP has never tuned a car. It was fairly obvious we were talking about WOT only in this thread considering the thread title and attached dyno graph.
Thread Starter
Safety Car
Joined: Apr 2008
Posts: 3,908
Likes: 10
From: Charleston SC
And remember that it pings at low rpm, high load/gear conditions..as I described earlier..
Safety Car
Joined: Jun 2005
Posts: 4,977
Likes: 256
From: St. Louis Missouri
It is absolutely the proper way to calibrate the high frequency (wot) cells by using lambda error. You set your PE to your desired AFR and dial in your maf table until your error is 0%, or as close to 0% as possible.
You do the same for the lower frequencies (part throttle), although PE may or may not come into play at that point. But that does not matter if you are tuning based off lambda error. After all, it is just commanded lambda vs actual lambda.
I gave a simplistic explanation because the OP has never tuned a car. It was fairly obvious we were talking about WOT only in this thread considering the thread title and attached dyno graph.
You do the same for the lower frequencies (part throttle), although PE may or may not come into play at that point. But that does not matter if you are tuning based off lambda error. After all, it is just commanded lambda vs actual lambda.
I gave a simplistic explanation because the OP has never tuned a car. It was fairly obvious we were talking about WOT only in this thread considering the thread title and attached dyno graph.
It seems we both agree on the ultimate answer to the OP's question, and frankly, that's all that matters. Based upon the dyno graph, I'd suspect something is amiss in the tune, rather than a mechanical failure (ignition, fuel system, etc.).
Race Director
Joined: Mar 2001
Posts: 11,405
Likes: 26
From: Whippany NJ
CI 6-7-8-9 Veteran
St. Jude Donor '08-'09
NCM Sinkhole Donor
Thread Starter
Safety Car
Joined: Apr 2008
Posts: 3,908
Likes: 10
From: Charleston SC
I wish I knew...
I bought the car from a the son of a used car salesman in Rutherfordton. He didn't seem to know much about it...and said the previous owner had the boltons installed and tuned.
I wish you guys were closer so I could just come take it to you. The local guys here are wanting $$$$ to tune it..
I bought the car from a the son of a used car salesman in Rutherfordton. He didn't seem to know much about it...and said the previous owner had the boltons installed and tuned.
I wish you guys were closer so I could just come take it to you. The local guys here are wanting $$$$ to tune it..
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Drifting
Joined: Apr 2009
Posts: 1,898
Likes: 9
From: Morrisville PA
I feel for you, because taking it to another dyno shop could result in the same thing. So many tuners out there that charge $500 and simply do a PE hackup. I would get a mail order tune from ECS since your car is just headers.
