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Old 02-07-2005, 03:02 PM
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firestone firestone is offline
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I did a little looking, to see what cams are being used with the 180cc heads. I also learned a little more about why it is better to use a single pattern cam instead of a dual pattern with a set of heads that flow like the AFR's while reading the first article. The first combo below is used on a 350, but remember that matching a head and cam has very little to do with what the size of the motor is. A matched setup on a 350 will be equally as matched on a 383, just with a lower powerband.

this combo (a 355) made 425 hp at 5800 RPM with a 224 @.050 cam ( for the most part duration is what determines your powerband) I think a slightly larger cam would have made a little more hp without sacrificing much torque.

http://www.chevyhiperformance.com/te.../148_0306_355/

Here is a page from the AFR website with several different cams in 383's with the 180cc heads. Notice that the largest cam that they used with the 180cc heads was the 12-432-8 (XR282HR)which is a hyd roller with 230-236 dur @.050 and .510 .520 lift. This cam is rated to 5800 RPM. This motor made 491 hp at 5500 RPM which is about right considering that you will drop 200-300 RPM because of the motor being a 383 rather than a 350 which the parts are based on. If you look at the XE274H cam it has 230 236@.050 dur and .487 .490 lift. If you added the 1.6 rockers to that, you would be at .517 .520 lift. these specs are almost exactly that of the XR282HR. Also notice that they did not bump up to the 12-433-8 (XR286HR 236 242 @.050 .520 .540 lift) until they started using the 195cc heads.

http://www.airflowresearch.com/dyno/chevy_dyno.htm

They only other thing I would consider would be running the single pattern 280H cam (230 230@.050 .480 .480 lift). with the 1.6 rockers that would put the lift at .510 .510. This would also work very well.

Here is the comp page with all the cams I talked about

http://www.compcams.com/Technical/Cu...ML/128-169.asp

Adam
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