tomas_wallin

What cam would you recommend for 454 (330hp) Gen V with std bottom end, L-29 Vortec heads, Edelbrock Performer intake/ Holley 300-42, Edelbrock 750cfm 1410 Marine, K&N 9" air filter and complete MSD marine ignition? The exhaust manifolds are stock with this kind of stainless elbows. I have not decided if i'm going to use dry or wet exhaust but probably dry!

The heads take a 540 lift with these springs, I don't really want to change the springs if possible.

I am not going to rev the engine past 5000-5100rpm, since I don't want to lose too much reliability.

It is going to be fed with 95octane.

I would be really pleased if I could reach 450hp.

The boat is a V-hull 24x7,3ft 3300bls. It maxed at near 60mph with a Mirage Plus 27P at 3800rpm with the 330 and a bad, badly adjusted carb.


(A friend of mine recommended this camshaft)

Thanks

Pat McPherson

That would be a good cam if you use the long risers. Dry exhaust would not be necessary.
If you buy stock Vortec heads, they will need to be machine for that much lift though.

Griff

I used the same cam in a warmed over 454mag. Its available in kit form with lifters also and bargain priced. It is almost the same cam as the 420 and 525SC.
Somebody else on the board used it also on a full rebuild and it dynoed right around 425hp. That was with rect port heads.

kit part # is 134242

WETTE VETTE

I used a 228/235 @ .050, .540" lift on a similar 454 and it worked great. We used with stock merc manifolds and didn't get any water from reversion. The cam was ground on a 112+4.

gLaSs HaLf FuLl

Cranes 132561 was the High end flat tappet that mecruiser
used on the Gen IV, V 400, 420, 525sc..... Shouldn't have
any reversion with those risers.

tomas_wallin

Now I have bought the L-29 Vortecs. They have been mounted but that engine was never fired, so the heads are brand new.

So the 134242 kit with cam and lifters is what you guys recommends if I would like to reach 420-450hp and about 5000rpm?!

Griff

Probably want to spin it to 5200-5400. Mine was still making good power up to 5400rpms. It fell off after that.
You should reach your hp goals without a problem.

Here's the old thread with dyno results and particulars also

http://www.offshoreonly.com/forums/s...ad.php?t=25932

bobl

If the engine is the stock 454 with small rods, cast pistons and crank you do NOT want to spin it past 5000 RPM. If that is the case running a smaller cam will probably work better, since you can't turn the RPM to benefit from the larger cam. Shoot for making a lot of torque and keep the RPM down so it will live.

tomas_wallin

Let's put it this way then:

The heads take a 540 lift with these springs, I don't really want to change the springs if possible.

I am not going to rev the engine past 5000rpm, since I don't want to lose too much reliability.

It is going to be fed with 95octane.

I would be really pleased if I could reach 450hp.


Does this change any of your previous opinions in cam selection?!

Pat McPherson

GM High Performance has a cam 228°/238°, .540/.540, 114LSA...
You can probably use the Gen V/GenVI non-adjust rockers too.
I doubt you will get 450HP out of it but 400+HP is likely.
Good Luck!