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 Hot Boat 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.

Want to see the boat its going it just go to www.SuperNova19.com

Griff

Crane 168731 would be a good choice off the shelf.

f_inscreenname

They are nice but don't you think the lift is a bit much for a tame motor?
0.587 int./0.610 exh. lift
And then there is the long exhaust.
http://store.summitracing.com/partde...5&autoview=sku
I used a duel plane cam in my last motor. I was always worried about water reversion. We have a couple long 6mph zones (miles) I have to go through now and then. After a long putting run I would have a hard time restarting the motor if I didn't get a chance to run it out a little before stopping. Like the rear plugs were getting wet. The last rebuild I replaced it with a single plane and that symptom went away.
Then there is the money. That is a expensive cam.

Pat McPherson

I used a Comp Cams Xtreme Marine cam that was 218°/224°, .510/.510, 112°LSA and an Edelbrock Performer when I rebuilt a 7.4L a few years back.
The boat, a 24' Pantera gained about 3mph over stock.
I don't think you can get much more than 375HP @ 4600 rpm with the peanut port heads without installing larger valves and porting them.
Good Luck and have Fun with your Project!

Griff

The 731 is big for the heads you have now. With a set of stock rect ports or aftermarket heads it would work well.

Actually, for now I would just put in a low budget flat tappet cam and upgrade to a bigger roller when you change the heads.

Try Crane #134241. Comes in a kit with lifters under #134242 for under $200. Its almost the same as the merc 420/525sc cam.

Elite Marine

Or select your color and cam and buy my long block that is in for a freshening.

It's a 468 with freshened Dart heads, Forged Crank, Eagle Rods, JE Pistons, Crane Gold Rockers, New Rings, New Bearings and New Oil Pump

f_inscreenname

Thanks Griff for the info.
Pantera Sorry bud but this is a backyard project. No money in the budget for all of that. For that matter I do not even need that much. To much and I will blow apart my Volvo 270. Yes I said a Volvo 270 with a 280T transom shield for trim.
I have a old Brownie boat that just needs a little more a$$ then a small block Mopar can deliver.

Dave F

If you insist on keeping those heads, the 218/218 is the better choice. the 731 cam is too big, the heads wont be able to let that cam get to it's potential.
In my opinion even the second choice cam (230/230) is even too big. Again those heads aren't going to give you anything past the 5000rpm range, which is where that cam will start really making some power.

Now I know you said you're on a budget, but with a 454 your best choice would be a set of large oval port heads in the hi 200 cc range. Like 270-290cc range. Definately not over 300cc. Then you can think about the 731 or the 230/230 cam.
The difference will be huge with a head change and cam to match what your heads can flow. Thats the key. There's no sense having a big cam without heads and exhaust that can let it work.

That brings me to the next subject of exhaust. I know you said you were looking at an aftermarket exhaust but let me stress that exhaust has alot...alot to do with what cam you can run. Any more than 6 degrees of overlap @ .050 on your cam and stock exhaust is recipe for disaster. So take that into consideration as well. The best thing to do is make sure your exhaust discharges the water at the very end, eliminating water in the exhaust stream. then thats one less thing to worry about.

DAVE

f_inscreenname

Thanks Dave.
I am totally with you in what you are saying. At the moment I am trying to make the best with what I have. Am I committed to these heads? No, there is just no money in the budget for new this season. The main objective of this year is to get the bottom end right and to get it to work. I am sure the motor will be fine but then I have to make it work in my boat with a 34 year old Volvo set up that’s in it now. Add in that I am swapping a Mopar small block for a Chevy big block I am sure there will be many more big fish to fry before its over. Next year I can start thinking about heads and other stuff. There is just so much to buy right now needing everything that even as cheap as Chevy parts are its still adding up quick.
Also like I said I really do not need much more HP then what came with the MIE340 from the factory. I just want to make sure they are not fake HP numbers and maybe even add a few to it and I will be happy.

PS Thanks for the tip on overlap. I will have to look into the cams closer. How do you feel about the center line? 9, 10, 11, 12, 14? Does it matter?

Donzi502

114 with wet pipes for my money. 112 if you put the water in futher down. 112 with E Tops. Definatly 114 with any kind od stock or similar to stock setup. Jas