I have an 03 Cobra with a 2.80 upper pulley. While tuning, the MAF was noted to be pegged at 5400 RPM. When this happens the AF defaults to rich, timing is pulled out and the HP does not climb after 5400 RPM. Any one had this issue or know best way to resolve?
Currently mine pegs at 6200 with the same pulley. I think your problem may also lie in the Diablo Chip. I purchased the car with the diablo and the tune was poor at best (16.3:1 air fuel at 3000 RPM) I have since switched to the new superchips program (with the chip not the handheld) and had the car dyno tuned. The new Superchips program really allows the tuner to work with each RPM and more finely tune the air fuel. 5400 just seems way low to max out the meter.
I had a custom tune done at the Dyno. The issue is the MAF is reaching 5 volts when the engine is only at 5400 RPM. Before the pulley change it was reaching 5 volts at 6500 RPM. I think on Monday I will call C & L or someone like that to ask for advice.
Pauls High Performance sells a MAF Clamp. This is small, firewall mount unit which lowers the voltage sent to the computer so it never really maxes out. I do not think they are too expensive, had one on my 99 GT worked great, allowed the shop to tune it properly. I think it will work on the Cobra too. Call Pauls High Performance in Lavonia Mich or go to PHP.com.
I have an 03 Cobra with a 2.80 upper pulley. While tuning, the MAF was noted to be pegged at 5400 RPM. When this happens the AF defaults to rich, timing is pulled out and the HP does not climb after 5400 RPM. Any one had this issue or know best way to resolve?
You are not alone. There are plenty of 03/04 Cobra's pegging their MAF's. Although you are doing it a little too easily and earlier in the RPM's than most. If I was you I'd look into one of these:
SCT Big Air 90MM MAF (Direct replacement for the stock Cobra 2003/2004 MAF)
If you do decide to go with this MAF neither your Predator OR the Superchips handheld tuners will work. You'll need either a custom flash tune from SCT or one of their chips.