MAF help!!

[caspy]

Hi guys...new to the forum but have a question re MAF tune.

I have stock 04 Monaro VXR/HSV GTS/ PONTIAC GTO, we have very successfully played with the stock tune and are very happy with the numbers we are pulling over std car, however, at about 10,000hz or 300 gm/sec and with no knock, the spark is being retarded and hence pulling power.

Is this as simple as putting slightly larger or granatelli maf in to overcome the higher end MAF metering ?

Tables suggest that it should be good for 12000hz and 512 gm/sec but if at 10000hz is it not getting to the point where the accuracy of the MAF calcs is going off and hence the PCM pulls spark as a precaution ?

Any help would be appreciated.
???

[MNR-0]

Could be engine TQ management kicking in. Monitor all the spark PIDS and also the amount of timing being pulled. You should be able to match that amount pulled to some table somewhere.

[caspy]

Torque management is completely disabled as far as i am concerned.

Pulling about 2 degrees at peak airflow. Looked at he TQM settings as had same thought but not there.

Thanks for the thought though

Also not pulling at the same point each time, varies so difficult to dial back in as cells vary.

[sean]

check your spak table fo grams/sec timming values in the upper flow anges. also could be your out of air meter on the big end. check for leans spots. and my last thought on the subject is maybe you have spark knock.

[caspy]

Would appear to have overcome problem. Seemed there was issue with the MAF. All sorted now. Pulling well. Thanks