Custom cam thread
#12
555ci JC Performance/Smith Power
Brodix 2x heads
Roots blown
6lbs boost
262/272
112 LSA
109 ICL
708/708
Crane solid roller cam, lobe designs from track roller profiles.
Using same cam in a 573 now
Tried Comp Cams same specs, made more boost but less power so numbers don't always tell the whole story.
Brodix 2x heads
Roots blown
6lbs boost
262/272
112 LSA
109 ICL
708/708
Crane solid roller cam, lobe designs from track roller profiles.
Using same cam in a 573 now

Tried Comp Cams same specs, made more boost but less power so numbers don't always tell the whole story.
#14
Registered

Joined: Jun 2009
Posts: 9,967
Likes: 6,456
From: Chicago
555ci JC Performance/Smith Power
Brodix 2x heads
Roots blown
6lbs boost
262/272
112 LSA
109 ICL
708/708
Crane solid roller cam, lobe designs from track roller profiles.
Using same cam in a 573 now
Tried Comp Cams same specs, made more boost but less power so numbers don't always tell the whole story.
Brodix 2x heads
Roots blown
6lbs boost
262/272
112 LSA
109 ICL
708/708
Crane solid roller cam, lobe designs from track roller profiles.
Using same cam in a 573 now

Tried Comp Cams same specs, made more boost but less power so numbers don't always tell the whole story.
Need more info
#15
Registered

Joined: Jul 2007
Posts: 2,640
Likes: 14
From: MI
#16
Registered

Joined: Nov 2004
Posts: 922
Likes: 54
From: Lago Vista TX
My camshaft WAS spec'd to work with the shortcomings of my particular build and may not be a good comparison to others
I wanted a decent idle and it had to work with my marginal EMI exhaust..
I wasn't after MAXIMUM hp.. Just wanted decent reliable power...
In fact, it made MORE hp than anticipated..


No idea on the reliability factor yet though..
only have about 10 hours on it..
Last edited by Boatally Insane; 10-04-2016 at 09:18 AM.
#17
Registered
Joined: Oct 2010
Posts: 922
Likes: 128
From: Hemlock, MI
My first Bob motor build Circa 2009/2010:
540 CI 9.2 CR, AZSM Honed MPI intake, extra porting, Dart Iron Eagle 308's cleaned up, EMI thunder long riser exhaust. Never dynoed, ran real strong though. Short life due to assembly error (my fault). Was supposed to be 5600-5800 RPM peak promised 600 hp. Fuel use and tune to make happy supports that plus a bit extra. Actually was thinking of using this cam again on motors in new boat this spring since I still have it then having clone made. Prob just go with one of the Lunati grinds now. They look nice especially for the price. Next builds more budget minded.
Standard firing order core# 315685
113.9 Lobe Sep
INT/EXH
Centerline 108.9/118.9
Duration 235.6/240.7
Lift .6207"/.61501"
2nd Bob motor build 2014:
548CI, 10.2 CR. AFR 335 full CNC heads, Edel. 454-R Dom intake, Accel 2100 CFM TB, Holley HP EFI, LS3 ignition, Same EMI Thunder long riser exhaust. Engine was a narrow peaky powerband but found the 6300 rpm peak finally with small prop. Boat ran 80 and climbing (never got peak setup/tune figured out) which requires ~700 HP with that hull, never dynoed. Promised 730-760 HP @6300 rpm. Engine had possible slight reversion. Never milked oil, but occasional steam from breathers. However, I did spec cam for full dry exhaust and was late in season when finished assy so never extended my tails through transom. Engine is on stand with probable spun rod bearing. Will be tearing apart to fix shortly and I am now interested to see what cam condition is.
8.1L firing swap core 8620
113.1 Lobe Sep
INT/EXH
Centerline 109.1/117.1
Duration 243.5/250.2
Lift .6804"/.66293"
540 CI 9.2 CR, AZSM Honed MPI intake, extra porting, Dart Iron Eagle 308's cleaned up, EMI thunder long riser exhaust. Never dynoed, ran real strong though. Short life due to assembly error (my fault). Was supposed to be 5600-5800 RPM peak promised 600 hp. Fuel use and tune to make happy supports that plus a bit extra. Actually was thinking of using this cam again on motors in new boat this spring since I still have it then having clone made. Prob just go with one of the Lunati grinds now. They look nice especially for the price. Next builds more budget minded.
Standard firing order core# 315685
113.9 Lobe Sep
INT/EXH
Centerline 108.9/118.9
Duration 235.6/240.7
Lift .6207"/.61501"
2nd Bob motor build 2014:
548CI, 10.2 CR. AFR 335 full CNC heads, Edel. 454-R Dom intake, Accel 2100 CFM TB, Holley HP EFI, LS3 ignition, Same EMI Thunder long riser exhaust. Engine was a narrow peaky powerband but found the 6300 rpm peak finally with small prop. Boat ran 80 and climbing (never got peak setup/tune figured out) which requires ~700 HP with that hull, never dynoed. Promised 730-760 HP @6300 rpm. Engine had possible slight reversion. Never milked oil, but occasional steam from breathers. However, I did spec cam for full dry exhaust and was late in season when finished assy so never extended my tails through transom. Engine is on stand with probable spun rod bearing. Will be tearing apart to fix shortly and I am now interested to see what cam condition is.
8.1L firing swap core 8620
113.1 Lobe Sep
INT/EXH
Centerline 109.1/117.1
Duration 243.5/250.2
Lift .6804"/.66293"
Last edited by Gimme Fuel; 10-04-2016 at 09:38 AM.
#18
Registered

Joined: Aug 2016
Posts: 312
Likes: 22
From: Reno, NV
Bought a boat with the motor apart and had the cam spec'd out.
It is a crane with
lift .631
duration 252
center line 113
These are the only numbers I got so I do not know if this is for both intake and exhaust. I am building a 548 BBC with 088 heads and 10:1 compression NA. This is for a 30ft advantage boat with a single 850 and Edelbrock Victor R manifold. Seems like a good place to start and the cam is still good. What do you think? I come from a drag racing background so I am trying to learn what works with boat motors as they are obviously a different animal.
thanks
It is a crane with
lift .631
duration 252
center line 113
These are the only numbers I got so I do not know if this is for both intake and exhaust. I am building a 548 BBC with 088 heads and 10:1 compression NA. This is for a 30ft advantage boat with a single 850 and Edelbrock Victor R manifold. Seems like a good place to start and the cam is still good. What do you think? I come from a drag racing background so I am trying to learn what works with boat motors as they are obviously a different animal.
thanks
#19
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Joined: Oct 2011
Posts: 173
Likes: 2
My build is the second one listed. The boat runs very good and I have not had any issues other than some dialing in with timing and carbs. Picked up 6 plus mph with a cam change (Bob M cams) and clean up of the heads. I have put only 10 hours or so on it but so far so good.
#20
Registered

Joined: Jul 2004
Posts: 433
Likes: 14
From: Angola NY
540ci
8.2cr
243/249 @.050
114 LSA
.662/.647 Lift
8.1 L firing order
Vortech Centrifugal Super charger
AFR 325 CNC chambers
At this point I am seriously considering not even taking a chance on this "Custom" Cam and going with something off the shelf. When this project started reliability was the Highest of priority with a stable long life valve-train and a target HP of 800HP was the Goal@6000rpm. I was willing to sacrifice max hp for reliability
Motor is sitting in my shop with short block assembled, camshaft installed ready to bolt together. Unfortunately I have lost interest in the project. I let myself get led along by Bobs BS for over a year and finally had to distance myself from him. What I found interesting was how quick he was to point to others for his repeated failures to deliver as promised. I have since spoke with a couple of individuals Bob pointed to with fault and it turns out Bob is the one not them who didn't deliver. Not a Fan of MK done with this jerk off.
8.2cr
243/249 @.050
114 LSA
.662/.647 Lift
8.1 L firing order
Vortech Centrifugal Super charger
AFR 325 CNC chambers
At this point I am seriously considering not even taking a chance on this "Custom" Cam and going with something off the shelf. When this project started reliability was the Highest of priority with a stable long life valve-train and a target HP of 800HP was the Goal@6000rpm. I was willing to sacrifice max hp for reliability
Motor is sitting in my shop with short block assembled, camshaft installed ready to bolt together. Unfortunately I have lost interest in the project. I let myself get led along by Bobs BS for over a year and finally had to distance myself from him. What I found interesting was how quick he was to point to others for his repeated failures to deliver as promised. I have since spoke with a couple of individuals Bob pointed to with fault and it turns out Bob is the one not them who didn't deliver. Not a Fan of MK done with this jerk off.



