Okay, here's your chance to tell me how you feel about a cam selection for a naturally aspirated 565cid marine engine. Go ahead and tell me what you really think---humor me if you like. It doesn't matter! I want to hear it. Not going to argue with anyone or anything---so don't be shy! I just want to know what you guys really, truely think about using these cams in my engines.

We pulled these cams out of a couple of engines---they are used, and I am not saying that I would use them, but I was wondering from you guys if the cams would be a wise idea of how they would perform in my 565cid engines with the 357 AFR cnd ported heads (as they sit now). Keep in mind that my goal is to make peak power at 5700-5800rpm. So don't be shy, go ahead and RIP into me---I promise I will not retaliate! So tell me what you think---don't hold back.

Hydraulic roller, duration @.050" lift is 220*/220* on 112* lobes. Lift is .560"/.560".

Ready.......set........GO!! Too small. Try a Crane 139741.

What are the 741 specs?

Here is the cam in merc 500EFI. 230/236 @.050 .598/.610". I think its safe to say is Merc certainly is not known as being anywhere near the ragged edge on their 502's......

I'd call the crane tech line and tell them your combo and see what they come back with...I bet its the 651 or something close to it. (IE custom)

Cam you gave might be a great start for a "hot" small block....

741 is 234/242 .610/.632"
651 is 244/256 .632/.632"

Mark,

I think it's time to take your pills.

Mark, go with diesels.

I built and Dynoed a pair of 510ci engines and used the Crane 139661 632/632 256/264 114 and the torque peaked at 4800 and the hp at 5800. That was with 325cc Merlin heads.

Mark, I guess these guys never built a pleasure engine that had heads that flowed 380 int, 280 ex at .600 lift. The Crane 651 was awful in a 540 with afr heads. I think you're a little conservative. I'd go more like 236/240 .630 lift. As a matter of factI can give you a grind number if you want.

Here is Crane's 454 Tow truck (kidding) HR cam.

214/222 @.050 .553/.576"

[QUOTE=PatriYacht]Mark, I guess these guys never built a pleasure engine that had heads that flowed 380 int, 280 ex at .600 lift. The Crane 651 was awful in a 540 with afr heads. I think you're a little conservative. I'd go more like 236/240 .630 lift. As a matter of factI can give you a grind number if you want.[/QUOTE

With the bigger cubic inch engine you need more camshaft to peak at your projected 5700-5800 RPM's. PatriYacht is right I would not use this big of a cam in a 454 or 502 that I wanted to peak around 5200-5300. Also with the 661 cam you need longer tail pipes and restrict the water to stay away from the reversion.