Performance Boats Forum banner

1 - 20 of 33 Posts

·
Registered
Joined
·
14 Posts
Discussion Starter #1
So I have a 460 bbf that is basically stock besides a small cam and I need some help from you guys. When its cold i have around 50 psi and all is well. as soon as it warms up it drops to like 10 and the lifters start clickin. so what do you guys think? oil pump? Main bearings? Also since im guna be tearing this thing down a little what do you guys recomend to get some more hps out this thing without spending my life savings? I was thinkin bigger cam maybe....what size is good for a jet?
 

·
Registered
Joined
·
557 Posts
Kinda sounds like mains. You didn't mention rpm but I'm assuming that you mean it drops to around 10 at idle?

KEn
 

·
Registered
Joined
·
14 Posts
Discussion Starter #4
ya around idle its super low 10ish and at a like 3500 it hit maybe 25 max. i pulled the motor out tonight and am going to tear into it tomorrow so well see. Any ideas on what cam to run?
 

·
Registered
Joined
·
2,234 Posts
If the lifters start clacking before the rods start knocking, I would bet on a spun main or cam bearing.

GT :)hand
 

·
Registered
Joined
·
14 Posts
Discussion Starter #6
thanks thats what i was thinkin too but im not a super motor head so i wasnt sure, just a garage guy that knows a little about a lot. Here is a pic of my boat so this thread doesnt totaly suck to read
 

Attachments

·
Living in a cage of fear
Joined
·
16,462 Posts
it doesnt look like anyone wants to answer you about the cam, i would suggest going to comp cams web site and downloading the dyno ,cam selector, it should give you a good suggestion on what to use and it will show you , what difference's each cam will make ,, good luck ,



http://compcams.com/camquest/default.asp

I've ran several of their "extreme marine" grinds in Chevy jets. Currently have the XM 296 HR (Hyd. roller) with 9.5:1 compression. But have ran the extreme 280 Hyd. flat with great results. That is with BBC, however.
You will like the 280 range hydraulic cams for not a lot of cash. Just don't get Too wild depending on your compression ratio.:)devil
 

·
NW Spectraholic
Joined
·
588 Posts
We had a Ford with low oil pressure once. I took it apart and noticed an oil pump bolt loose and it had spit out the mounting gasket. :p
 

·
www.highflowdynamics.com
Joined
·
1,161 Posts
So I have a 460 bbf that is basically stock besides a small cam and I need some help from you guys. When its cold i have around 50 psi and all is well. as soon as it warms up it drops to like 10 and the lifters start clickin. so what do you guys think? oil pump? Main bearings? Also since im guna be tearing this thing down a little what do you guys recomend to get some more hps out this thing without spending my life savings? I was thinkin bigger cam maybe....what size is good for a jet?
The diminishing oil pressure could be a number of things, but it sounds typical of worn bearings/loose bearing clearances.

A good budget cam that you can run for cheap is the Summit Racing house brand camshaft SUM-3501. It's a good camshaft for the stock marine 460 because it is mostly duration (easy on the OEM valve springs). If your current camshaft is bigger than the one I recommended, then you will need more valve train upgrades (pushrods, valve springs, valves, etc), and the engine's performance would be vastly improved from also porting the heads, particularly the exhaust ports in your case.

Run a Holley 850 cfm Double Pumper carburetor.

LO
 

·
www.highflowdynamics.com
Joined
·
1,161 Posts
If the lifters start clacking before the rods start knocking, I would bet on a spun main or cam bearing.

GT :)hand
It's possible but the lifters are fed oil in these engines before the mains see it, and so a spun main does not cut off oil supply to the lifters.

LO
 

·
mo balls than $cents$
Joined
·
11,734 Posts
The diminishing oil pressure could be a number of things, but it sounds typical of worn bearings/loose bearing clearances.

A good budget cam that you can run for cheap is the Summit Racing house brand camshaft SUM-3501. It's a good camshaft for the stock marine 460 because it is mostly duration (easy on the OEM valve springs). If your current camshaft is bigger than the one I recommended, then you will need more valve train upgrades and the engine's performance would be vastly improved from also porting the heads, particularly the exhaust ports in your case.

LO
i've ran that 3501 summit cam before, worked great in my taylor sj in frt of a a cut
 

·
www.highflowdynamics.com
Joined
·
1,161 Posts
I've ran several of their "extreme marine" grinds in Chevy jets. Currently have the XM 296 HR (Hyd. roller) with 9.5:1 compression. But have ran the extreme 280 Hyd. flat with great results. That is with BBC, however.
You will like the 280 range hydraulic cams for not a lot of cash. Just don't get Too wild depending on your compression ratio.:)devil
IF you want to run a camshaft this big in your 460 you will have to do a lot of valve train upgrades and/or be willing to spend a lot more money than it sounds like you care to.

In Heat, perhaps you should tell us how much hp you want and what your budget is...

LO
 

·
Living in a cage of fear
Joined
·
16,462 Posts
IF you want to run a camshaft this big in your 460 you will have to do a lot of valve train upgrades and/or be willing to spend a lot more money than it sounds like you care to.

In Heat, perhaps you should tell us how much hp you watn and what your budget is...

LO
True, the Hyd. flat will require springs, retainers. Lifters are a given any way, I believe.
Does that motor have pedestals, or studs??
 

·
mo balls than $cents$
Joined
·
11,734 Posts
True, the Hyd. flat will require springs, retainers. Lifters are a given any way, I believe.
Does that motor have pedestals, or studs??
should have pedestals, but crane makes a conversion kit cheap. most bbf spring pockets are fairly shallow and will require either longer valves or the pockets cut to run a big lift cam.
 

·
Living in a cage of fear
Joined
·
16,462 Posts
should have pedestals, but crane makes a conversion kit cheap. most bbf spring pockets are fairly shallow and will require either longer valves or the pockets cut to run a big lift cam.

It has been a LONG time since I worked in a machine shop!:D:D
Seems we used to get like $40.00 to cut pockets on the fords, and about the same to convert to screw in studs and plates? (plus parts$$)
 

·
Registered
Joined
·
785 Posts
a good oil pan will be your best friend.
 

·
www.highflowdynamics.com
Joined
·
1,161 Posts
Seems we used to get like $40.00 to cut pockets on the fords, and about the same to convert to screw in studs and plates? (plus parts$$)
The D3VE heads have a combustion chamber that is ~0.100" deeper into the head than the early-style (D0VE, etc) heads and so the valves are about 0.100" shorter than the early-style valves. Therefore, you can install early-style valves into D3VE heads to serve as "+0.100" long D3VE valves," and take care of the (bigger) 1.900" installed valve spring height that way.

Milling D3VE rocker arm bosses for 7/16" stud and guideplates usually costs a couple hundred, but can vary.

But I digress: It is possible to set up the D3VE heads with their pedestal-style rocker arms and manage about 0.550" lift reliably.

LO
 

·
Registered
Joined
·
14 Posts
Discussion Starter #19
you guys rock!:)devil thank you for all the input so far. So i pulled the pan off and the crank and rod bearings r shot but the crank looks good. my block casting number D1VE says this thing is outa a 71 lincon mark 111 but im not sure now if its a 460 thats only what i was told it was by the seller. As far as the cam goes if i go with something like the extreme marine cam do i have to run solid lifters or just upgrade my valve trane? my buddet is probably around 500 or so but i dont want to skimp and buy crap either.
 

·
Registered
Joined
·
200 Posts
Be sure you check the cam bearing something caused the bearings to go bad. Are you going to add a HV oil pump to your list?
 
1 - 20 of 33 Posts
Top