Go Back  Offshoreonly.com > Technical > General Q & A
cam advise for 454 mag >

cam advise for 454 mag

Notices

cam advise for 454 mag

Thread Tools
 
Old 03-05-2017, 05:50 PM
  #1  
Registered
Thread Starter
 
Join Date: Sep 2014
Location: Osage Beach MO
Posts: 57
Likes: 0
Received 0 Likes on 0 Posts
Default cam advise for 454 mag

I know, yes it's another nagging cam question looking for advice. I want to put a very aggressive and noticeable cam in a pair of 454 mag motors in my 35 fountain. The motors are true 365 HP mag Motors with 200 hours on them. I will be adding a Holley 750 carb on a Victor jr. Single-plane intake. The heads are the large Square port and will be cleaned up in the bowl area. I'm looking for a cam in the 2000-6000 RPM range. I do have Gil exhaust manifolds and dry to the transom tips where the water and exhaust meet so I hope reversion should not be a problem. I do want to use a hydraulic flat tappet cam with less than .600 lift and a pretty aggressive duration. Would a 110 lobe center be too tight for a marine application?

I do like the Comp 4X4 Cam 11-243-4 cam which is 234/244 @.050 with .564/.570 lift on a 111 lobe center

The boat will not be raced and I'm not looking for huge numbers, I just want a good aggressive sound that will work with my application.

I forgot to add the blocks are standard bore with four bolt Mains and a steel crank again it only has 200 hours on each engine and I want to leave the stock pistons and compression. Thanks!

Last edited by blownsvt1; 03-07-2017 at 02:34 PM. Reason: up date info
blownsvt1 is offline  
Old 03-05-2017, 05:57 PM
  #2  
Registered
iTrader: (1)
 
Join Date: Jul 2007
Location: MI
Posts: 2,639
Received 12 Likes on 6 Posts
Default

Why not a roller? I worry about flat tappets with low zinc oils. If you go for the performance the sound will come with your cam choice.
JRider is offline  
Old 03-05-2017, 06:17 PM
  #3  
Registered
iTrader: (3)
 
Join Date: Apr 2006
Location: Toledo Oh
Posts: 10,061
Received 690 Likes on 276 Posts
Default

...

[ATTACH=CONFIG]565339[/ATTACH]
Attached Thumbnails cam advise for 454 mag-cam.jpeg  
phragle is offline  
Old 03-05-2017, 06:27 PM
  #4  
Registered
Thread Starter
 
Join Date: Sep 2014
Location: Osage Beach MO
Posts: 57
Likes: 0
Received 0 Likes on 0 Posts
Default

I'm not using a roller just because of cost I have a limited budget. I use the Valvoline racing oil which has the highs zinc content
blownsvt1 is offline  
Old 03-05-2017, 06:29 PM
  #5  
Registered
Thread Starter
 
Join Date: Sep 2014
Location: Osage Beach MO
Posts: 57
Likes: 0
Received 0 Likes on 0 Posts
Default

Let me clarify I'm not putting the cams in just for the sound I want a workable setup if I wanted just the noise I would put one of those stupid thumpr cams in and call it good
blownsvt1 is offline  
Old 03-05-2017, 06:35 PM
  #6  
Registered
iTrader: (3)
 
Join Date: Oct 2007
Location: yorkville,il
Posts: 8,427
Received 87 Likes on 49 Posts
Default

Originally Posted by JRider
Why not a roller? I worry about flat tappets with low zinc oils. If you go for the performance the sound will come with your cam choice.
^^^^this.your initial investment with a hyd roller is higher but imo it is the way to go.you might think about a 168731 crane hyd roller.a 750 carb is great for a small block but with a good exhaust and the right cam a 850 would be a better choice for your 454.if buying a carb new the 850 is a no brainer.
mike tkach is offline  
Old 03-05-2017, 06:42 PM
  #7  
Registered
iTrader: (3)
 
Join Date: Oct 2007
Location: yorkville,il
Posts: 8,427
Received 87 Likes on 49 Posts
Default

if a hyd roller is not in the budget and you absolutly can,t swing it their are some good hyd flat tappet cams but i have no idea on what one would work for you,i have not used a hyd flat tappet cam in a boat for a long time.
mike tkach is offline  
Old 03-05-2017, 06:54 PM
  #8  
Registered
iTrader: (3)
 
Join Date: Jul 2004
Location: chicago
Posts: 11,332
Received 71 Likes on 39 Posts
Default

Heres a buddys 454's. Started life as 370's, basically, a 454 Mag. Boat ran upper 50's back when engines were stock. Runs 63-65 now. Rectangle port GM heads, Single Plane Proffessional products "hurricane" intakes, 850 quick fuel marine carbs, stellings headers, roller rockers, and a crane 134561 cam. 236/246 114 LSA, 551/571 lift. Flat tappet. one of the engines expired 4-5 years ago, due to a leaking riser on the stock 454 mag iron exhaust manifolds. Mike Tkach redid that engine for him. The other engine, has been going strong for the last 15 years or so. Believe it or not, they did NOT revert water with those cams, and stock exhaust. But, he got a good deal on the stellings, and put them on. The engine that was recently rebuild, recieved the crower cam saver lifters, that have the groove cut in them. The other engine, still has the standard flat tappets. Boat has close to 2000 hours on it, and has never had a cam lobe or lifter failure. He beats the chit out of this boat, and engines, and they just keep running!

https://www.youtube.com/watch?v=3LriYY1QCtU
MILD THUNDER is offline  
Old 03-05-2017, 06:56 PM
  #9  
Registered
iTrader: (3)
 
Join Date: Jul 2004
Location: chicago
Posts: 11,332
Received 71 Likes on 39 Posts
Default

https://www.youtube.com/watch?v=X7olqjFN8p8
MILD THUNDER is offline  
Old 03-05-2017, 07:11 PM
  #10  
Registered
iTrader: (3)
 
Join Date: Jul 2004
Location: chicago
Posts: 11,332
Received 71 Likes on 39 Posts
Default

I'd prob run a cam like the old Mercruiser 440HP 454 "cyclone" engine. This cam is very close in specs to it. 233/241 110 LSA, 106 ICL. Assuming you will be running aftermarket exhaust, and decent length risers, or fully jacketed risers.

https://www.summitracing.com/parts/lun-10110704
MILD THUNDER is offline  


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.