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Discussion Starter #1
My build is a 521 ford with Performer RPM heads (60669),Harland sharp roller rockers, Performer RPM intake, 9 to 1 compression, Marine 850 Holley, exhaust is logs with snails exiting under water,Berkely JE pump have A & AA impellers. want max RPM to be around 5000 to 5500. The boat is 20' long.

Comp cam- Hyd. roller 111 intake center line, Dur @ 50, 244 intake, 250 exhaust, 113 lobe sep.,605 intake lift, 622 exhaust lift.

Crane- Hyd. roller
226 intake, 230 exhaust, 112 lobe sep.,522 intake lift, 530 exhaust lift.

These are the cams that Comp and Crane suggested. It sounds like I should be worried about sucking water with the DUR. OF THE COMP?

What do you guys think. Thanks
engine
 

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My build is a 521 ford with Performer RPM heads (60669),Harland sharp roller rockers, Performer RPM intake, 9 to 1 compression, Marine 850 Holley, exhaust is logs with snails exiting under water,Berkely JE pump have A & AA impellers. want max RPM to be around 5000 to 5500. The boat is 20' long.

Comp cam- Hyd. roller 111 intake center line, Dur @ 50, 244 intake, 250 exhaust, 113 lobe sep.,605 intake lift, 622 exhaust lift.

Crane- Hyd. roller
226 intake, 230 exhaust, 112 lobe sep.,522 intake lift, 530 exhaust lift.

These are the cams that Comp and Crane suggested. It sounds like I should be worried about sucking water with the DUR. OF THE COMP?

What do you guys think. Thanks
engine
the comp looks the best to .let the big mill breath more.and your lob sep on the comp is 113 no reversion problems with either one to be honest at least this is what i think.

why did thye spec cams with 112-113 lobe seps,huh????kinda funny to me,anyway i like the comp good luck,travis:D
 

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E-7 Sheepdog (ret)
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Always hard to tell of the duration concerns BUT IMO the duration of the Comp cam will push your power peak to well above your 5300RPM limit you desire.

The crane needs more lift,a nd IMO a bit more duration, arround 240* or so,

I'm running a 454 quite happilly with a hyd FLAT of .565" lift and 242* duration, orriginally with log exhausts and snails, now with Lightning headers.
Isky 280H but with custom (more aggressive) ramp rates.
 

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Discussion Starter #4
Always hard to tell of the duration concerns BUT IMO the duration of the Comp cam will push your power peak to well above your 5300RPM limit you desire.

The crane needs more lift,a nd IMO a bit more duration, arround 240* or so,

I'm running a 454 quite happilly with a hyd FLAT of .565" lift and 242* duration, orriginally with log exhausts and snails, now with Lightning headers.
Isky 280H but with custom (more aggressive) ramp rates.
Was there a big difference when you went to the headers? Thanks
 

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Discussion Starter #5
the comp looks the best to .let the big mill breath more.and your lob sep on the comp is 113 no reversion problems with either one to be honest at least this is what i think.

why did thye spec cams with 112-113 lobe seps,huh????kinda funny to me,anyway i like the comp good luck,travis:D
Why is the lob Seps. fun
I'm not cam smart. Thanks
 

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Why is the lob Seps. fun
I'm not cam smart. Thanks
well im not either try to be:p

the 112-113 lobe seps will help big time with water reversion.;)probably why,but for the most part peeps have a hard time realting cam profiles to jet boats,as opposed to cars or prop boats.

for me if i had to choose it would be the comp you have abig mill,not a stock 454 like smokin is talking about.
with the logs i would stick around the 110-112 lob sep.:)hand
 

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mo balls than $cents$
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i like the comp better. even though you're sporting nice bbf heads, they're still lacking in the exhuast flow dept(just a bbf deal)and that comp cams is stronger in that dept , imo, of course:D

the duration is getting on the verge but if you're mindfull of header injection output you should be fine.

if you go with the comp cam, you'd be better served by a ab or b cut also;) it needs to get closer to 6k to do some work, the lunati would be the better "ski jet" choice if that's what you're trying to do:)bulb
 

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With the Ebrocks and your CID you going to need around 8 degrees of split at .050" to optimize the heads. Also at your CID I would go single plane intake. With that kind of cube and stroke you wont sacrifice a bit of low end. Depending on what kind of power you want to make would decide camshaft type. A roller will give you more all around power but you are going to have to change springs on those Ebrocks.
 

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With the Ebrocks and your CID you going to need around 8 degrees of split at .050" to optimize the heads. Also at your CID I would go single plane intake. With that kind of cube and stroke you wont sacrifice a bit of low end. Depending on what kind of power you want to make would decide camshaft type. A roller will give you more all around power but you are going to have to change springs on those Ebrocks.
You need to listen to this guy Dustin. He can help you get right were you want to go!! ;)


BTW....Nice oil pan, Thanks Bro!! :)devil
 

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www.highflowdynamics.com
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My build is a 521 ford with Performer RPM heads (60669),Harland sharp roller rockers, Performer RPM intake, 9 to 1 compression, Marine 850 Holley, exhaust is logs with snails exiting under water,Berkely JE pump have A & AA impellers. want max RPM to be around 5000 to 5500. The boat is 20' long.

Comp cam- Hyd. roller 111 intake center line, Dur @ 50, 244 intake, 250 exhaust, 113 lobe sep.,605 intake lift, 622 exhaust lift.

Crane- Hyd. roller
226 intake, 230 exhaust, 112 lobe sep.,522 intake lift, 530 exhaust lift.

These are the cams that Comp and Crane suggested. It sounds like I should be worried about sucking water with the DUR. OF THE COMP?

What do you guys think. Thanks
engine
Well....

If you must choose between those two profiles then the Comp is the overall better choice for the engine combo. That being said, the overall engine combination and parts selected makes me hope you are very familiar with establishing proper valve train geometry and also prepared to modify the pushrod holes in the heads--should it be necessary--thanks in particular to the use of the H-S rocker arms in conjuction with the hydraulic roller lifters...neither of which I'd use in a 385 Series except under rare circumstances and only when absolutely necessary/no other options, and hopefully never need to use them together in a build, ever.

LO
 

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E-7 Sheepdog (ret)
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Was there a big difference when you went to the headers? Thanks
I gained 200RPM/50HP on stock large oval port heads. No other changes, just headers and a 1-jet step up all arround.

I had already changed the intake to an RPM Air Gap Performer 2 years previous.
 

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Discussion Starter #12
Well....

If you must choose between those two profiles then the Comp is the overall better choice for the engine combo. That being said, the overall engine combination and parts selected makes me hope you are very familiar with establishing proper valve train geometry and also prepared to modify the pushrod holes in the heads--should it be necessary--thanks in particular to the use of the H-S rocker arms in conjuction with the hydraulic roller lifters...neither of which I'd use in a 385 Series except under rare circumstances and only when absolutely necessary/no other options, and hopefully never need to use them together in a build, ever.

LO
Why are the H-S rocker arms bad and why not run a hyd. roller cam. I haven't picked a cam yet just trying find one that will work the best on limited knowledge. I'm having the motor put together by a professional.
 

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Discussion Starter #13
With the Ebrocks and your CID you going to need around 8 degrees of split at .050" to optimize the heads. Also at your CID I would go single plane intake. With that kind of cube and stroke you wont sacrifice a bit of low end. Depending on what kind of power you want to make would decide camshaft type. A roller will give you more all around power but you are going to have to change springs on those Ebrocks.
The machine shop put new springs in when repairing the heads 200LB & 2" .770 max lift. For HP I would like as much as I can get keeping the RPM to 5000 to 5500.
 

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The machine shop put new springs in when repairing the heads 200LB & 2" .770 max lift. For HP I would like as much as I can get keeping the RPM to 5000 to 5500.
im going to honest here.call chris straub and talk to him;)

pay the extra money to get his cam.it will be very much worth it in the end.


like he told me on the phone 1 time.you can pick a cam as good as me with guessing;).im asking why guess get it done right the first time

there are alot of off the shelf cams that work good.but not as good as his will,hope this helps,travis
 

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cj812
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i told you in the pm to get ahold of lakesonly so he can speak with chris straub, if you choose to not listen to these guys your a fool.
 

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Discussion Starter #16
I'm listening and will call. I'm just trying to under stand all the info here. I'm not just letting some one pick a cam for me. Did that last time and was not happy.

I sure like this forum.
 

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cj812
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I'm listening and will call. I'm just trying to under stand all the info here. I'm not just letting some one pick a cam for me. Did that last time and was not happy.

I sure like this forum.
just call paul i already gave you the # he will tell you all you need to know, his customer service is exclent just ask any body who has dealt with him. including me;)
 

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I'm listening and will call. I'm just trying to under stand all the info here. I'm not just letting some one pick a cam for me. Did that last time and was not happy.

I sure like this forum.
well must have not been paul or straub.lol!!!!might have even been me.:)sphssthey will help you understand what you want to try and do with this project lots of good folks out there to help you.good luck:)hand
 
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