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sprink58 08-12-2012 08:08 PM


Originally Posted by Diego9040 (Post 3751680)
:whistle:I would love to get some opinions on the cam specs above design by Bob , well I guess if they were design by Bob Madara, the name says it all,right?

My take is with that lift he is really building some cylinder pressure...and quickly. That's a big advantage of roller cams...you can do things that are for the long haul with lift that you marginalize the durability with a flat tappet. Running that lift at that duration in a heavy boat wouldn't last very long or be very well mannered at the dock with a flat tappet set up. It will be relatively smooth with a roller. He custom tailored that grind to your exhaust which is capable of getting those gasses out quickly.

Your boat should get up on a plane fast and run like a "Raped Ape" all the way to the top. I look for a very strong and fat torque curve.

BBCLiberator 08-12-2012 08:26 PM


Originally Posted by sprink58 (Post 3752147)
My take is with that lift he is really building some cylinder pressure...and quickly. That's a big advantage of roller cams...you can do things that are for the long haul with lift that you marginalize the durability with a flat tappet. Running that lift at that duration in a heavy boat wouldn't last very long or be very well mannered at the dock with a flat tappet set up. It will be relatively smooth with a roller. He custom tailored that grind to your exhaust which is capable of getting those gasses out quickly.

Your boat should get up on a plane fast and run like a "Raped Ape" all the way to the top. I look for a very strong and fat torque curve.

I pretty much agree, I certainly won't speak for the man, but the lift numbers he gave on my cam were WAY higher than I expected. This will put some extra load on your springs, but the roller engine can handle it, though I do plan to do springs about every 300 hours. All I know is Bob helped me assemble the proper stuff and my boat runs real string for what it is. In fact a friend runs a 201 Liberator (typically about 3-4 mph faster similarly powered vs. my hull) that is about 2 mph slower than my boat is now with his assembled component 502. He did it his way and saved about $1000 to his credit, the boat runs fine. But the endless stream of grief I've been giving him is really starting to irritate him AND I don't need a can of ether to get mine to start, I need two cranks ;)

Now I won't say you can't duplicate his results on your own, I'm not that naive. But if you don't know or are way off, he sure quickly steers you down the correct path. That to me is worth more than the minimal price difference to an off the shelf cam. And most importantly he listens, to what you wants and needs are, because lets be real it's not ALWAYS about max power...it sure wasn't for me

Going from a Gen V 502 with SM manifolds already on it, to a roller conversion with full roller rockers, a bob cam and an edelbrock intake, I picked up 7mph, in the boating world that is HUGE.

Diego9040 08-12-2012 09:30 PM


Originally Posted by sprink58 (Post 3752147)
My take is with that lift he is really building some cylinder pressure...and quickly. That's a big advantage of roller cams...you can do things that are for the long haul with lift that you marginalize the durability with a flat tappet. Running that lift at that duration in a heavy boat wouldn't last very long or be very well mannered at the dock with a flat tappet set up. It will be relatively smooth with a roller. He custom tailored that grind to your exhaust which is capable of getting those gasses out quickly.

Your boat should get up on a plane fast and run like a "Raped Ape" all the way to the top. I look for a very strong and fat torque curve.

I just told Bob do it as if this was your boat, and that is what he did of course he mentioned he would not compromise durability , and I liked that, i will post more info as soon as get the boat on the water.

Thanks for your input!

Diego9040 08-12-2012 09:44 PM


Originally Posted by BBCLiberator (Post 3752176)
I pretty much agree, I certainly won't speak for the man, but the lift numbers he gave on my cam were WAY higher than I expected. This will put some extra load on your springs, but the roller engine can handle it, though I do plan to do springs about every 300 hours. All I know is Bob helped me assemble the proper stuff and my boat runs real string for what it is. In fact a friend runs a 201 Liberator (typically about 3-4 mph faster similarly powered vs. my hull) that is about 2 mph slower than my boat is now with his assembled component 502. He did it his way and saved about $1000 to his credit, the boat runs fine. But the endless stream of grief I've been giving him is really starting to irritate him AND I don't need a can of ether to get mine to start, I need two cranks ;)

Now I won't say you can duplicate his results, I'm not that naive, but if you don't know or are way off, he sure quickly steers you down the correct path. That to me is worth more than the minimal price difference to an off the shelf cam.

Going from a Gen V 502 with SM manifolds already on it, to a roller conversion with full roller rockers, a bob cam and an edelbrock intake, I picked up 7mph, in the boating world that is HUGE.

I agree, 7 mph is a lot of gain, by the way, Bob spoke to Edelbrock tech support to make sure the springs were acceptable and he even gave my builder some recommendations as far as adjusting them a bit.

Very eager to seeing results now.

Thanks for your reply.

87MagnumII 08-13-2012 06:22 PM


Originally Posted by Diego9040 (Post 3751196)
Cams from Bob Madara were Delivered to me today,here are the specs :

Hydraulic roller

LSA 112
Duration .50 222/228
valve lift .532/.524

I am expecting to turn these engines up to 5200 rpm

I will post results in about a week,

Thanks everyone again , it was a pleasure to work with Bob, hopefully outcome will be just as good.

Are these specs with 1.5 or 1.6 ratio rockers?

Diego9040 08-13-2012 11:22 PM


Originally Posted by 87MagnumII (Post 3752960)
Are these specs with 1.5 or 1.6 ratio rockers?

These are w 1.5 ratio full roller rockers.

Uncle Dave 09-14-2012 06:12 PM

So what did they make?

UD

Diego9040 09-22-2012 08:51 PM

Uncle Dave,

I am still waiting for him to finish them up but I am also changing the seals on the drives,changing gimbal rings ,shift cables ,bellows, and every other part in the gimbal housing.Once I am on the water I don't want any big surprises.
I wish it was all ready by now but is not as fast as I wish I have some pics taken 1 weeks ago will post them next.

Diego9040 09-22-2012 09:04 PM

here some pics so far
 
4 Attachment(s)
still waiting, but hopefully it will all come out good. Thanks everyone for your input

Diego9040 09-22-2012 09:08 PM


Originally Posted by Diego9040 (Post 3782423)
Uncle Dave,

I am still waiting for him to finish them up but I am also changing the seals on the drives,changing gimbal rings ,shift cables ,bellows, and every other part in the gimbal housing.Once I am on the water I don't want any big surprises.
I wish it was all ready by now but is not as fast as I wish I have some pics taken 1 weeks ago will post them next.

I had a lot of play in the drives and since engines were not installed yet, decided to make sure eveything was right with the drives and gimbal housing.


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