GTC's folder-Looking for gtc for 427 SB Ford

[TurboNova]

If you have slip on collectors they have to fit tight with no leaks. I have found on our chassis dyno that slip on collectors funnel air at idle and off idle that will throw off the O2 sensor. If you can feel any air around the collector while the engine is running then this is what is happening. Any air leak before the O2 is critical because it introduces fresh air into the exhaust and the O2 will read it as lean. A leaking collector will also cause backfires in the exhaust because of a rich mixture and air coming into the exhaust.

We have even put silicone in the collector before slipping them on to help seal them up. What ever you do it has to be an air tight fit. Fix you leaks before we go any farther.

Put in the tune I sent you and let it idle the timing should be 14 degrees at idle but look at the bdtc timing on the spark table screen and double check that it matches what your timing light says.