Hydrolic Roller Cam Selection

[Shelbytexas]

Please help:
I have a Shelby Convert (3550lbs) and am having Kieth Craft build my engine. It is a 427 block with a 428 crank, KC Stage 2 Edelbrock Alum heads (10:1), DaVinci 850 Card, H/S Roller Rockers, 2.19/1.73 valves, PI alum intake. 4 spd car. Red. We are going with a Hyd Roller Cam. I do not like the lopey sound of a real agressive Cam and need 11 - 12 lbs of vaccuum for the power breaks.

Current selection is either a 236/242 @ .050 with .600 lift or a 242/248 @ .050 with .600 lift.

Mostly street driving, some track. Some say the former cam is a "baby", but the latter may be a bit wild.

Please help with any comments. Thanks! Ken

[Jack21]

Ken,

For a mostly street motor, you might want to go a little more conservative on the duation. Something in the 224I/232E range. The motor will be a lot torkier where you use it. Run the numbers on Dyno 2000 and look at the torque curve in the 2000 - 3500 RPM range. A hydraulic roller in this range will give you awsome torque, and 15" - 16" vacuum at idle for you bakes.

Carb wise, take a look at the Demon 850DP.

Trans wise, the new Tremec T-600 might make a better choice, and give you a better cruise.

[Shelbytexas]

Jack - Thanks.
I was running the Comp Cams Hyd. XE 274 (.562/.565 230/230) with unworked Edelbrock heads. I got 285, 291 and 301 Hp on three runs on a chasis dyno (OUT OF A 454!). Torque was good at 385, but HP dropped hard at 5200. Obviously I was dissapointed. The new head work and a better, slightly more aggressive CAM looks to be the answer. I tend to agree with you, though, going on the conservative side...looking for some input as to what each of these cams will sound like and what kind of vaccuum they will pull. Ken

[The Dreamer]

My advice. Worry only about vacuum. I have a KC motor and the it dynoed over 600 ft-lbs when the dyno started taking measurements. You WILL have enough torque down low.

[Shelbytexas]

Dreamer- I totally agree. With a 454 in a 4 spd car with this light of a rear end, I will easily trade low end torque for high end torque. I would really like the car to still be going at 6000 rpm. I am only worried about vaccuum and would like to keep the idle from waking up the neighbors. Trying to see if anyone has any experience with vaccuum and noise with similar cams (the car also has headers)....
Ken