smokeonthewater
God
Not me... I like the 4 cyl plan
Saw these in the Summit store online
- Thread starter aussie
- Start date
spareparts
God
Aussie, you're doing what i always wanted to do with my old room mates Stingray 176(had the 3.7L 165 hp), more power to you for doing it, but just don't over complicate it
THEFERMANATOR
God
What he said. Nothing against the 3.7L, and I think MERCRUISER screwed up by ditching it for the 4.3L V6. But I agree that your over complicating it many ways. Build the bottem end up, put a good head on it, call a good cam company and have them see if they can do a regrind to peak the engine for your application, and call it a day. Electric water pumps and other extravagant things on a boat are just head aches waiting to happen. Build the engine up, but keep it simple.
smokeonthewater
God
smokeonthewater
God
interesting article
http://www.enginebuildermag.com/Article/91130/inside_flat_tappet_camshaft_andlifter_technology.aspx
"Improved lifter designs can also reduce the risk of lobe wear and cam failure. Some companies now make lifters that have a small pin hole in the bottom of the lifter to feed oil directly to the lobe. The hole may be centered over the lobe or offset slightly to one side. Another trick that can improve cam lubrication is to cut a small slot in each lifter bore so oil can drip down directly onto the cam lobes.
Cam Treatments
Another way to reduce cam lobe wear is to have the camshaft nitrided. Nitriding is a process where the camshaft is baked inside a sealed chamber at high temperature while being exposed to a pure nitrogen atmosphere. As the nitrogen diffuses into the surface of the iron, it forms a hard layer a few thousandths of an inch deep that improves wear resistance. It’s not a coating and does not change the dimensions of the camshaft.
Some cam manufacturers offer nitriding as an option. The treatment costs about $100, and increases the surface hardness of the cam to about Rockwell 55 to 60. Some say the bottoms of the lifters should also be nitrided, but others say if the cam lobes and lifters are the same hardness it may increase the risk of galling during break-in.
Some cam suppliers use a process called “Parkerizing” that applies an acidic lubricant to the outer surface of the cam to protect against galling during break-in. It’s a temporary treatment and does not change the hardness of the cam.
Another way to reduce cam wear issues is to use an iron alloy that contains more nickel, or to go with a billet steel cam (both of which are more expensive than cast iron). Chase Knight of Crane Cams said his company is now using an upgraded camshaft material that is about three points harder than a standard cast iron alloy. Crane also offers a micropolished surface finish that reduces friction and improves the break-in process."
http://www.enginebuildermag.com/Article/91130/inside_flat_tappet_camshaft_andlifter_technology.aspx
"Improved lifter designs can also reduce the risk of lobe wear and cam failure. Some companies now make lifters that have a small pin hole in the bottom of the lifter to feed oil directly to the lobe. The hole may be centered over the lobe or offset slightly to one side. Another trick that can improve cam lubrication is to cut a small slot in each lifter bore so oil can drip down directly onto the cam lobes.
Cam Treatments
Another way to reduce cam lobe wear is to have the camshaft nitrided. Nitriding is a process where the camshaft is baked inside a sealed chamber at high temperature while being exposed to a pure nitrogen atmosphere. As the nitrogen diffuses into the surface of the iron, it forms a hard layer a few thousandths of an inch deep that improves wear resistance. It’s not a coating and does not change the dimensions of the camshaft.
Some cam manufacturers offer nitriding as an option. The treatment costs about $100, and increases the surface hardness of the cam to about Rockwell 55 to 60. Some say the bottoms of the lifters should also be nitrided, but others say if the cam lobes and lifters are the same hardness it may increase the risk of galling during break-in.
Some cam suppliers use a process called “Parkerizing” that applies an acidic lubricant to the outer surface of the cam to protect against galling during break-in. It’s a temporary treatment and does not change the hardness of the cam.
Another way to reduce cam wear issues is to use an iron alloy that contains more nickel, or to go with a billet steel cam (both of which are more expensive than cast iron). Chase Knight of Crane Cams said his company is now using an upgraded camshaft material that is about three points harder than a standard cast iron alloy. Crane also offers a micropolished surface finish that reduces friction and improves the break-in process."
aussie
Senior Member
that's fine I just wanted to explain myself why im doing what I am . I haven't cut the camshaft yettttttttttt - I gave Crow cams the specs of the engine and told them what im doing and asked for a cam grind in a solid the specs they gave me were a lot smaller than the hydraulic that's in it. Im not going to use that grind as im sure it will make less power than the merc one as they would of done a lot of testing to get the cam rite .What I plan to do is to get the cam read and find a grind something close or a touch bigger in a solid .I have a heap of grinds that I got done on paper just need to choose one. I have in the past had the face of lifters reground with more radius to help break in of the cam I have seen lobes wearing of days after they were installed. I do want to go solid mainly because I had to buy push rods and rollers for the head and I wont be going fishing everyday . so if I need to adjust them once a year it wont be a problem
aussie
Senior Member
I forgot another reason im keeping the 3.7 a few members told me that they make good power for what they are and I only took the boat for one short run and had the push rod problem so I couldn't tell how good it was