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Old 03-10-2011, 01:36 PM
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Cliff R Cliff R is offline
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Compression is important in power (torque) production. Once you get past mind-set that a "perverbial brick wall" of 9.5 to 1 exists for these engines on pump gas,, the engine builder can use the compression to get these engines to manage larger cams.

The problem with this line of thinking, is that you can lower the compression and still manage the same cam. The larger cam takes a LOT of "wind" out of the lower compression engine, specifically down in the "normal" driving range, low rpms and at idle.

If you drop out a half point or so compression, to get the engine to run compariably to the higher compression one, at the same cid, reduce the cam duration by about 10 degrees.

In other words, a cam down around 214/224/112 would have been a better choice all the way around......Cliff

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Old 03-10-2011, 01:54 PM
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462ta 462ta is offline
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will have to look to see where the dyno runs are then figure out how to post, Cliff just ordered couple air horn gaskets , ripped mine at the prim rod hanger.

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Old 03-10-2011, 03:15 PM
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slowbird slowbird is offline
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Quote:
Originally Posted by Cliff R View Post
In other words, a cam down around 214/224/112 would have been a better choice all the way around......Cliff
We ran a cam very similar to that in our first 400 ran great. Ended up run 12.7s I believe with that cam, and untouched 16 heads.

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