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  • 2 weeks later...

Got it going, excuse the crappy red breather lines.

Cruises and idles very nicely. Limiter set at 4500 for now and will not drive it now till it goes for a run-in tune in few days.

Would the tune be out by a fair bit? Difference being New motor with higher comp and the twin cam head vs old motor low comp and sohc. Everything else is basically the same.

post-78438-0-35280100-1423565290_thumb.jpg

Exactly.

Its due to the fact the AFM reads the actual amount of air entering the engine so fuels according to that.

Using a map sensor the ecu calculates the amount of air based on pressure and temperature. As the different setup will draw more air at the same pressure, the fuelling will be off.

In both cases a tune is required, as the ecu is going to reference different cells in different conditions, however if the car previously had an AFM and still did with new setup, the fuelling would be very close still.

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