[cobrarkc]

Just an FYI and if you have a MassFlo system Chris should have already told you this. THe Ford O2 sensors need to be 12- 18" from the exhaust port to function properly. If you have them in your collectors they will not heat up enough and you won't go into closed loop. Some guys on EECTuning.com have plyed with pulse timing to fool the ECU when using long tube headers. You can do a search over there and get some good information.