Hello tuning a buddies airboat engine and every time we start it up it's lean (17-18 afr) for the first 10-15 seconds. Then the tone of the engine changes and the afr drops to around 14.7.
I've tried reloading his previous tune and it does the same thing.
The only changes made to the engine are 243 heads and Texas speed 224/224 .600/.600 109 lobe separation.
Any idea what can be causing this? Thanks for any help.
I will post a copy of the tune when I get back to the house.