how much Horsepower?

Originally posted by WETTE VETTE
These guys are right. Not enough cam to pull 6000 RPM. I would even go bigger than the one that Bobby recommended. Ultra Dyne has a low compression solid roller for 502-540 pleasure boat motors. The duration is 264/270 @.050 with .670" lift on a 110. That is only my opinion.

THis cam vette found is great for a 540 I'd go with it and I like ultadyne they make cams that are dead on !!!


Great Vette !!!!

[PatriYacht]

bobby daniels, since you are on the line I was wondering if you could answer a jetting question. I bought a boat with 540's, dual 750's on a holley tunnel ram. The engines have solid lifter cams and dry pipes. At low speeds the mix is very rich. Haven't had a chance to check the plugs yet but the transom is covered with soot from one ride. (crummy Mich. weather). What do you think a baseline would be for jetting and power valves on these?

I like your combination. That combo should make pretty close to 600 horsepower. You better check the compression, it should be at least 160 in every cylinder. Is the ignition timing correct? You should have 34 degrees advance by 3500 rpm. You should be jetted fine with the stock jets (A carburetor that requires bigger jets than stock is on an engine that is overcarbed. An overcarbed engine has a low vacuum signal at the venturis requiring larger jets to maintain adequate fuel flow. A low vacuum signal can't pull as hard on the jets so they need to be bigger). Check the float levels and make sure the engine compartment is supplying enough air to the carbs. I would suggest checking the camshaft timing. While you are in there set it up without any camshaft advance. Set the intake lobe centerline at 112 degrees ATDC.
Good luck
Sincerely
Dennis Moore

[MIKEHTMSR24]

10:1 comp
Alum. Edelbrock RPM heads (ported and polished with 2.3's and 1.9's)
Straight up cam timing
Port matched Team G intake with a Barry Grant 850 flowing 930 cfm 78's & PV- 88's no PV.
HP was 683 @ 5684 and torque was 676 @ 4700
Wet CMI headers

The only thing I have done is went down in fuel 2 jet sizes all the way around.
250 hours on motor

[MIKEHTMSR24]

[KNOT-RIGHT]

Originally posted by Dennis Moore
I like your combination. That combo should make pretty close to 600 horsepower. You better check the compression, it should be at least 160 in every cylinder. Is the ignition timing correct? You should have 34 degrees advance by 3500 rpm. You should be jetted fine with the stock jets (A carburetor that requires bigger jets than stock is on an engine that is overcarbed. An overcarbed engine has a low vacuum signal at the venturis requiring larger jets to maintain adequate fuel flow. A low vacuum signal can't pull as hard on the jets so they need to be bigger). Check the float levels and make sure the engine compartment is supplying enough air to the carbs. I would suggest checking the camshaft timing. While you are in there set it up without any camshaft advance. Set the intake lobe centerline at 112 degrees ATDC.
Good luck
Sincerely
Dennis Moore

Thanks for the reply Dennis, It looks like you read the topic.
We are planning another run this pm with the fatter jets
the fuel levels have been checked on the trailer. timing is locked at 32
degrees. The props have been cut back to 16.75 diamiter.
Cam timing has never been checked will check were its in at.
will check compression also. Back to the basics.

Cut and installed two scoops in the Engine hatch to aid
in the fresh air.

thanks again

[KNOT-RIGHT]

Originally posted by MIKEHTMSR24
10:1 comp
Alum. Edelbrock RPM heads (ported and polished with 2.3's and 1.9's)
Straight up cam timing
Port matched Team G intake with a Barry Grant 850 flowing 930 cfm 78's & PV- 88's no PV.
HP was 683 @ 5684 and torque was 676 @ 4700
Wet CMI headers

The only thing I have done is went down in fuel 2 jet sizes all the way around.
250 hours on motor

Thank you for your response looks like you got quite a setup there
I see your combo pulls to 4700 rpm I think your heads and comp ratio is helping If my combo pushes 580 hp each this boat should
see close to 100

Glad to see that cam is working for you.

[KNOT-RIGHT]

Originally posted by bobby daniels
THis cam vette found is great for a 540 I'd go with it and I like ultadyne they make cams that are dead on !!!


Great Vette !!!!

I can see your getting Frustated I can only Imagine some of the people you must deal with. I am just Trying to figure out if these
motors are producing 600 hp. I have read many of your posts
and people respect your opions I am sure youve earned it.
If the cam is not big enough and the power is being made to
low of a rpm where i need the power higher up on the rpm.
then Changing the cam is the answer It will be done. I guess
I am just trying the basics first before i start Pulling out cams.

Thanks Again For your Help.

PS. If We change the cam is there a Cam that I can put in
that will satisfy the application and take care of future Mods.
Such as a 10-71 Supercharger??? You cant stop at 100

[WETTE VETTE]

Let us know how it turns out. From where you are now your rig is going to need another 300 or so HP to gain 14 MPH. I personally doubt your motors are running that bad right now to be down that much. My honest opinion is that 10 MPH lie that is so common in magazine articles. Do the things Dennis Moore recommended and get everything right. I am sure there is some more there, but 14 MPH from some tuning is hard to buy. If you get there let me know. I have been chasing 100 for the past year and I am only looking for 2 or 3 MPH.

[KNOT-RIGHT]

Originally posted by WETTE VETTE
Let us know how it turns out. From where you are now your rig is going to need another 300 or so HP to gain 14 MPH. I personally doubt your motors are running that bad right now to be down that much. My honest opinion is that 10 MPH lie that is so common in magazine articles. Do the things Dennis Moore recommended and get everything right. I am sure there is some more there, but 14 MPH from some tuning is hard to buy. If you get there let me know. I have been chasing 100 for the past year and I am only looking for 2 or 3 MPH.

Im reluctant to beleave that but your most likely
right on.....