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Old 01-29-2019, 12:55 PM   #25
Gunkk
Thank you Al Oppenheiser!
 
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Drives: Red Hot A10 ZL1 Convertible
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Quote:
Originally Posted by Pollock View Post
Make sure you are using Top tier rated fuel. The mechanic I was talking to said that helps too.

Edit: I also cant remember what the technical term is but you get carbon build up when both the intake and exhaust valves are open at the same time. That is something a catch can wont help.
You're probably referring to Atkinson cycle engines, which keep the intake valve option for a portion of the compression stroke, which reduces the effective compression ratio and results in a slightly more efficient cycle due to less losses from compression work (at the expense of total power output).

Combining Atkinson cycle & GDI is not only a waste of effort because fuel can be controlled directly, but it's disastrous for valve buildup.

Atkinson is useful in non-GDI hybrids where efficiency matters more than power, and the electric motor can cover the gap.
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