Cam choice help

[f_inscreenname]

I just started my 454 build and need some help with a cam choice. This is the plan. Dip the block and hone the deck and cylinders to the new pistons and wrist pins I just bought. They are .210 Domed Speed pro’s. That should give me 9.38 to 1 with the heads I am using now (Peanut heads 14092360) and will give room to move a little when I pick up a different set in the future. The heads are completely rebuilt and will be fine for a year or so. Molly rings, new bearing (cam, main & rod). True Double Roller timing chain. Yes I will degree the cam when its time. A new cam, lifters and valve springs (matching set). Melling HV oil pump with HV shaft (gotta have good oil pressure). Edelbrock Air Gap dual plane manifold. Mercruiser Thunderbolt ignition and distributor with a Super Stock coil. My cooling system off of my Chrysler and new single wire alternator also. Topped off with my Edelbrock 750, some 8mm wires and a few other things.
The last thing will be some sort of header exhaust like I had on my Mopar (Hi Tek‘s).
Do you think this cam will work? I have read that a few guys on here say go wilder and then there is a couple guys that are saying to run a milder cam. My Nova is only 19’ so I thought I would split the difference. I am not looking to break the sound bearer. A respectable 375 to 400HP should be enough for it.
http://www.naparts.com/ProductModelD...tModelId=15054
Chevy 396-502 cid, RPM Range 2000-4500, Adv Dur 296 intake/296 exhaust, Dur @.050 218 intake/218 exhaust, Valve Lift 519 intake/519 exhaust, Lobe C/L 110.

Or something like this?
http://www.naparts.com/ProductModelD...tModelId=15058
Chevy 396-502 cid, RPM Range 2800-5800, Adv Dur 288 intake/288 exhaust, Dur @.050 230 intake/230 exhaust, Valve Lift 544 intake/544 exhaust, Lobe C/L 109.

 

[Reel Poor]

Re: Cam choice help

Does the origional cam have a # on it?

 

[f_inscreenname]

Re: Cam choice help

Ya, I think it has 1548 or 1549 stamped on the old cam.

 

[jimmbo]

Re: Cam choice help

Go to a MerCruiser dealer and order a cam from him

 

[f_inscreenname]

Re: Cam choice help

Go to a MerCruiser dealer and order a cam from him

Sorry bud but pretty much all cams are made by the same company or two. Just have to find the right grind for what I want to do and Mercruiser's tend to be to tame. Ohhh and they cost a million dollars but thanks for the help.d

 

[Reel Poor]

Re: Cam choice help

I found this info on page 220 of the GM Performance catalog.


GM Part #
10185060

Hyd Flat Tappet 454ci

Duration @ 50" lift {degrees}
I 220
E 220

Maximum Lift {in}
I 500
E 500

Lobe Centerline {deg}
115

Technical Notes
Street high performance and marine cam as used in Gen V 454 HO engines. Advance 5 degrees. Use springs P/N 10185058.

 

[paulie0735]

Re: Cam choice help

IMO either of those cams will require a spring change along with the cam. The standard springs won’t survive. The second one will mean the cylinder heads must be equipped with the correct valve springs, screw-in studs, guide plates, and hardened pushrods. The increased loads and ultra high acceleration rate of the hi-performance lobe shape make this a necessity for valve train stability. Remember this is a marine installation not automotive, check with the cam manufacturers to see what they recommend for a marine application with the standard valve train components. I think you will find the original cam is near the limit already.

 

[f_inscreenname]

Re: Cam choice help

Don't worry Paulie most of that is part of the matching kit. Everything but the pushrods.
I am still looking for a cam. Not really set on either one though. I have some more looking into. Need to find one with better separation.

 

[f_inscreenname]

Re: Cam choice help

Knowing the original spec's for the cam that was in the motor and then seeing it again in a post-
Duration @.050; Intake .234* /Exhaust .238*
Lift;Intake .271 / Exhaust .282
With 1.7 rockers isnt that (?) Lift; Intake .461 / Exhaust .479

 

[rodbolt]

Re: Cam choice help

go look for the seirra cam for either the 340 HP or 330 HP merc and go play.
296 degree,depending on your x dimension and riser configuration may lead to heartache.
I really really dont wish you to discover the term, reversion.
its a very very expensive term.
I have 7 big blocks I am rebuilding/replacing now due to that term.

 

[f_inscreenname]

Re: Cam choice help

I know that term. A little to much cam in a 302 once. Its amazing what a little water can do.
I'm cool with what you are saying. Just looking for a starting point. Been on a bunch of sites. I got replays from mild to wild. Just trying to sort it all out.

 

[Autotech1]

Re: Cam choice help

F_in, Please read this. Flat tappet cams are failing more than 30 % than just 4 years ago for a few reasons. Read this and youll be ahead of the game.





http://www.racingheadservice.com/Articles/Details.asp?ID=-1228096506

 

[f_inscreenname]

Re: Cam choice help

Hey AT
I read about that a couple days ago. But thanks for the heads up. I figure I will only be running it for a season anyways then maybe a roller set up.
The more and more I am reading about cams the more and more I understand on how they work. Some pretty crazy stuff for some bumps on a steel shaft. From what I gather on the stock cam is its a torque monster. I even found out that the intake valve (according to a website valve lift should only be 25% of the valves width, then it drops off) that Merc even went a little overboard with it. Some interesting stuff. They were even running a duel plane cam 20 years ago. Wild.
The more I learn the closer I will be to getting the right one.8)