I have a Turner Chip in my 90 535, I have been thinking of putting the stock chip back in. That way I don't have to run Premium fuel. What is the going rate for a chip. I have the original box and sheet for it. It is not one of those imitations from ebay.
you will lose more MPG with the stock chip that the added cost for premium fuel. I dont know if your chip increases mileage though.
95 E34 530I V2.37
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