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Barbapapa Barbapapa is offline
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Join Date: Jan 2007
Location: Atlanta
Posts: 305
Quote:
Originally Posted by Larry Herman View Post
Very nice work. 2 quick questions about your motor, if I may:

1) I assume that the reversion that you mentioned is eliminated due to the extremely short intake runners?

2) What are the holes in the cylinder sleeves for?
Larry, the reversion issue is eliminated for part throttle operation because there's a big throttle blade right there. The overall length of the intake tract isn't important. A typical ITB engine has the throttles almost completely closed during most cruising, more so with a big engine. Both the proximity of the throttle to the valves and the very fact that there's one for each cylinder are factors.

If you have 2 different engines with ample valve duration, one with ITBs and one without, the ITBs will have a smoother idle without the lope and light throttle driveability will be better.

The holes in the sleeves are to allow coolant to flow freely.
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Mike S.

79 928 Racer 427ci 32v 640WHP
Old 08-03-2009, 12:51 PM
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