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651??? made by crane???
curious what are the numbers on this cam??

Quote:

Originally Posted by mike tkach (Post 4494595)

i am confused,is the piston .018 below the deck or above the deck.also on my cam,the 651 has been used in hundreds of 540s,i have used it in my own 540,s with great results but the max power will be closer to 6400 rpm.

Quote:

Originally Posted by MILD THUNDER (Post 4494818)

. You also dyno'ed that engine without the procharger as well didn't you?

Sure did... :)

http://i130.photobucket.com/albums/p...psjc8p7gin.jpg

Would the 651 cam have caused reversion with my wet exhaust ? Seems many who run it run dry exhaust .

As far as the IAT, it was close to 100° in the shop when we dynod and I was feeding the intercooler off the bypass port on the crossover , so the water was heated some by the block.. When it finally goes in the boat it'll likely have its own pickup...

Thank you all. I find it interesting that the power curve of th SC just keeps climbing with that small of a cam and NA it falls off around 5500.

Quote:

Originally Posted by NDH2O (Post 4494878)

Thank you all. I find it interesting that the power curve of th SC just keeps climbing with that small of a cam and NA it falls off around 5500.

May have pulled even more with the SC we didn't try..
I chickened out due to my Eagle rotating assembly, AND due to the fact it was already well above my target hp anyways..

Sure doesn't sound like 1000+ hp at idle.. ;)

https://www.youtube.com/watch?v=kprKxCUKvz4

Quote:

Originally Posted by NDH2O (Post 4494878)

Thank you all. I find it interesting that the power curve of th SC just keeps climbing with that small of a cam and NA it falls off around 5500.

A SC and Turbo supplies more air then the motor does NA, thus able to feed the motor at higher rpm's than NA.

Quote:

Originally Posted by Boatally Insane (Post 4494886)

My gosh.... It's gotta be hilarious when some fool pulls up to you with his ratty sounding 454/502/540 and you drop the hammer. I would swear that sounds like a 330 or ok maybe a mag but... Good for you. That's awesome.

Quote:

Originally Posted by MILD THUNDER (Post 4494820)

You won't get .018 above the deck under operating conditions. The piston grows when its hot.

With a .051 gasket, and even with the piston rock at max, you'd still have .033 of clearance. Once the piston grows, the rock will be less. If you were to average the measurement, say .018 above deck when rocked cold, and say, .012 below deck when rocked the other way, you can say, the piston is .004 above the deck, and use that for your measurment. Thats how I was taught to do it, using a deck bridge and a dial indicator. So far it seems to work.

if the center of the piston is .005 above deck and has .018 out of the bore during cold rock it is .018 above and below center line of piston with a flat top.yes as the piston gets to operating temp it is growing so the .018 rock will be less when at operating temp.so lets say the rock goes to .008 at operating temp,now add .010 for carbon buildup you still need to allow .018 when figuring what head gasket to use.this is why i said i would use a .060 thick gasket.a little extra clearance won,t hurt but not enough clearance will cause all kinds of problem,s.this is how i have done it for 40 years so i guess it is working.don,t forget that the piston rock is .018 during cold running until the piston starts to grow and with the build up of carbon on the piston top one must allow clearance for it.

Quote:

Originally Posted by flashgordon (Post 4494849)

651??? made by crane???
curious what are the numbers on this cam??

info is in post 6.

Quote:

Originally Posted by MILD THUNDER (Post 4494818)

I noticed those IAT temperatures on your dyno sheet. Pretty cool info. I always thought the prochargers were soooooo much cooler running , and how you could run way more boost than a roots. Those IAT readings, are basically the same , if not a little hotter, than my 420 Mega Blower making 8lbs boost with a superchiller on the dyno. I love actual data, rather than "heresay" or someones "opinion'' based on sales and marketing claims.

You made that power with a 239/246 cam in full marine dress with EMI manifolds with an M4 and only 9 lbs boost, thats pretty good.. Maybe the 244/256 crane 651 would have been better. I don't know. You also dyno'ed that engine without the procharger as well didn't you?

One thing to look at is his IAT is without fuel so he don't show any cooling effect VS a roots supercharger with fuel.

Quote:

Originally Posted by 14 apache (Post 4494990)

One thing to look at is his IAT is without fuel so he don't show any cooling effect VS a roots supercharger with fuel.

For sure. It still is what it is though. It be pretty cool to see what a non intercooled procharger does, vs a non intercooled roots. I know what the temps are with a non intercooled carb'd 1071 roots at 6k rpm. Still no where near as hot as the internet claims, but about 25-30 degrees hotter than the intercooled version. Im not super impressed with the "superchiller" brand intercooler results. Maybe the whipple ones work better, but they are sure expensive.

The Port EFI isn't getting the fuel cooling effect, but it should offer some help in the fuel distribution if its tuned right.