Thread: What cam/compression in my Blown 392???

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Hello Everyone, I'm getting ready to order my blown 392 Hemi kit from PAW to put in my '32 Ford. It's a street/strip car {mostly street} w/ a built turbo 400 trans & trans brake, 3000 RPM true stall {w/ a 499 tq & 460 hp sm bk Chev}, 9" Ford rear w/ 4:11 True Track, Hoozier 12.5 X 31 Pro street radials on street, M & H 10.5 x 30 slicks {real ones} for play & race , car weighted 2450 w/ sm bk Chev motor, I'm seriously considering a Gear Vendors overdrive. Let's see, the PAW 6:71 blower kit comes w/ 8 to 1 blower pistons but lower compression ones are available on special order, I'm getting Hot Heads aluminum heads {these are 100 cc, I've been told that the original Hemi heads are between 100 to 110 cc's}. The 3 cams available from PAW are; #1) 225/225 duration @ .050", .480/.480 lift, adv. dur is 280/280, lobe lift is .320, lobe seperation is 114.... #2) 235/235 dur @ .050, .519/.519 lift, adv. duration is 290/290, lobe lift is .346, lobe sep is 114.... #3) 245/245 dur @ .050, .549/.549 lift, adv. dur. is 300/300, lobe lift is .366, lobe sep is 114.

My 3 questions are; #1) Which cam should I use from Paw? or Should I order one from another cam manufacture other than Paw? #2) They said with the pulley's they supply that the boost is around 6 to 8 lbs. Should I find out exactly which pulley's they supply & give this info to you folks to get the boost info closer? #3) Is 8 to 1 low enough w/ a blower or should I special order pistons? THANKS & have a great week-end everyone! Bill

Blower Drive Service recommends 8.0:1 as the max for 8 lbs of boost. They also recommend a 110 degree lobe separation angle for use with gasoline (114 for use with alcohol).
Check out the first chart to determine the type of driving you will be doing and use their grind number in the left hand column to choose your cam in the second chart....
http://www.blowerdriveservice.com/camspecs.php
http://www.blowerdriveservice.com/bcamspecs.php

....Thank You Tech, BDS confusses me cuz they recommend a 110 lobe seperation while most of the others recommed a 113-114. Not sure why this is?...... Hummm, but a max of 8:1 compression for 8 lbs of boost looks to me like it wouldn't hurt to have a little bit lower compression ratio..... Thanks again, Bill