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Camshaft Selection/Engine Setup

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Old 03-07-2016 | 09:25 AM
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Default Camshaft Selection/Engine Setup

I figured I would post to get some input on this setup that is currently being built.

GEN VI 454
+.060 Overbore
088 Heads/Cleaned Up
Stock Crank and Rods
Stainless Marine Full Exhaust
Performer RPM Dual Plane
Holly 800 DP w/ 1" Open Spacer (As needed)
Would like to try to get 9.5 CR

The machine shop recommended Comp Cam 11-451-8 for this setup.Thoughts? Still trying to find the right pistons for this as well.

As stated before, this is my first full build for a boat. Any input is appreciated.
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Old 03-07-2016 | 09:42 AM
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i would not use that cam.if it is in the budget go with a hyd roller,if not look at something in the 235 at .050 range with a wider lsa.if you want longivity stay under .600 lift.edit in,i just noticed you have a gen6 engine,it is a hyd roller engine so no reason to go with a flat tappet cam.

Last edited by mike tkach; 03-07-2016 at 09:45 AM.
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Old 03-07-2016 | 09:45 AM
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It is a HR and has the following specs

Grind Number: CB XM 284HR-12
Cam Style: Hydraulic roller tappet
Basic Operating RPM Range: 2,200-5,800
Intake Duration at 050 inch Lift: 230
Exhaust Duration at 050 inch Lift: 236
Duration at 050 inch Lift: 230 int./236 exh.
Advertised Intake Duration: 284
Advertised Exhaust Duration: 290
Advertised Duration: 284 int./290 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.547 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.547 in.
Valve Lift with Factory Rocker Arm Ratio: 0.547 int./0.547 exh.
Lobe Separation (degrees): 112
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Old 03-07-2016 | 10:16 AM
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Originally Posted by SB
It is a HR and has the following specs

Grind Number: CB XM 284HR-12
Cam Style: Hydraulic roller tappet
Basic Operating RPM Range: 2,200-5,800
Intake Duration at 050 inch Lift: 230
Exhaust Duration at 050 inch Lift: 236
Duration at 050 inch Lift: 230 int./236 exh.
Advertised Intake Duration: 284
Advertised Exhaust Duration: 290
Advertised Duration: 284 int./290 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.547 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.547 in.
Valve Lift with Factory Rocker Arm Ratio: 0.547 int./0.547 exh.
Lobe Separation (degrees): 112
Looking at pistons from my other posts,

http://www.ebay.com/itm/Sealed-Power...hVAQnC&vxp=mtr

or

http://www.ebay.com/itm/Speed-Pro-TR...item232c921bc3

Open to suggestions, only got 1 response to my other post...
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Old 03-07-2016 | 10:19 AM
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oh snap,i typed in the wrong number when i google,d it.disregard my post,that would be a decent cam for that build.problem with that cam is it is not a step nose cam so the gen6 cam retainer plate won,t work.
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Old 03-07-2016 | 10:24 AM
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Originally Posted by distantthunder
Looking at pistons from my other posts,

http://www.ebay.com/itm/Sealed-Power...hVAQnC&vxp=mtr

or

http://www.ebay.com/itm/Speed-Pro-TR...item232c921bc3

Open to suggestions, only got 1 response to my other post...
i like the second option,9 to 1 with iron head should be a winner.
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Old 03-07-2016 | 10:26 AM
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Originally Posted by mike tkach
oh snap,i typed in the wrong number when i google,d it.disregard my post,that would be a decent cam for that build.problem with that cam is it is not a step nose cam so the gen6 cam retainer plate won,t work.
Good catch. Here is the one for the Gen VI (step nose)
COMP Cams Xtreme Marine Camshafts 01-451-8
http://www.summitracing.com/parts/cc...8/applications
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Old 03-07-2016 | 10:41 AM
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Originally Posted by SB
Good catch. Here is the one for the Gen VI (step nose)
COMP Cams Xtreme Marine Camshafts 01-451-8
http://www.summitracing.com/parts/cc...8/applications
Would that work with my existing rockers? This is a picture taken during teardown

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Old 03-07-2016 | 11:40 AM
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From that picture you have a hydraulic flat tappet camshaft set-up. You will need camshaft, roller lifters, timing chain set, dog bones, retainer plate w/ bolts, push rods, valve springs, retainers and keepers. You will have to replace the rocker arms also, I like the Comp Cams stamped steel roller arms for budget builds, but a full roller rocker is more conventional. May need rocker studs as well, can't tell if you have adjustable valve train. It's definitely worth the money. If you have a heavy boat I would take about six degrees of duration @ .050 away from the cam selection for more low end torque. What size is your oil cooler?
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Old 03-07-2016 | 11:46 AM
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Originally Posted by No Coast
From that picture you have a hydraulic flat tappet camshaft set-up. You will need camshaft, roller lifters, timing chain set, dog bones, retainer plate w/ bolts, push rods, valve springs, retainers and keepers. You will have to replace the rocker arms also, I like the Comp Cams stamped steel roller arms for budget builds, but a full roller rocker is more conventional. May need rocker studs as well, can't tell if you have adjustable valve train. It's definitely worth the money. If you have a heavy boat I would take about six degrees of duration @ .050 away from the cam selection for more low end torque. What size is your oil cooler?
That is a roller, just has the spider removed.
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