5.7 oil capacity increase?

[aldfaa]

Rebuilding a 96 5.7, installed a LT-4 HOT cam by GM and will be installing vortex heads.

The current old pan is a GM 10242245 5 qt pan. Is it recommended to go to a 6 qt pan like the GM 10055765 or stay where its at?

Plan on standard volume/standard pressure pump. Speaking of that what is recommended a .625 inlet tube or the .750?

Reason I am wondering is the bearings looked like they were oil starved, this was with a standard volume/pressure. Was thinking that at high RPMs the pump was sucking air.

Suggestions?

 

[Bifflefan]

Re: 5.7 oil capacity increase?

In the strictest sense, all wet sump engines will at some time "suck air" in the oil system. Thats why high dollar race engines dont run them. They run a dry sump.
That being said, if you were oil starving, there was a reason for it. Like running low on oil, or something.
Now, Im always for more oil, It will run cooler and last longer.
As for the rest, that is something the pan and or pump maker can answer. They dont spend tons of money testing for no reason.
High volume is good, high pressure is not as help full. 10 psi per thousand RPM is plenty.

 

[Danny Mc]

Re: 5.7 oil capacity increase?

When I build those engs I use a deep sump pan and the Melling Select op with steel coupler sleeve and Moroso pick up.

 

[Alpheus]

Re: 5.7 oil capacity increase?

installed a LT-4 HOT cam by GM

Big mistake. This is not a CAR engine.

Rule#1 is that you do not put hot cams in boats.

Google "Water Reversion" and you will see...

 

[GLENN M]

Re: 5.7 oil capacity increase?

go with the 6 quart pan.make sure the pickup is at back of motor, and goes to bottom of pan use a windage tray, stock pump is good you can change pump relief spring to 60 psi and forget about it.stick with stock size pickup and have it brazed on if its press on type

 

[wca_tim]

Re: 5.7 oil capacity increase?

I run a 7 qt baffled pan on my small block.

NEVER put a high volume pump on a marine engine unless you have a very specific reason to do so (and I can't think of one right now). With a high volume pump, it's possible to empty the pan after a long hard run - starving the bearings right when you need them the most. High quality standard volmue pump, with 60# relief and brazed pickup as mentioned above. If you're goig to run the snot out of it, the best additoin is a remote oil filter and thermostatted oil cooler / heat exchanger to keep the oil cool. The bottom end of a marine engine takes a lot more stress for longer times than a car engine and run hotter oil temps in general. cooling the oil helps from a number of fronts and also increases the volume of oil in the system...


The hot cam will work, BUT not with a factory exhaust. You will at a minimum need extensions welded onto your factory risers (to introduce water further downstream), long after market risers or best, a high quality set of aftermarket manifolds and risers designed for performance: IMCO, EMI, Stainless marine, Etc... otherwise it will suck water back up into the engine at idle, water is not compressible and can wreak havoc on your engine (permanently).

that combo will make something approaching 400 peak horsepower at 5000-5500 rpms with an edelbrock airgap rpm and 750 cfm carb on it...

 

[aldfaa]

Re: 5.7 oil capacity increase?

Specs on the cam are:

Cam Style Hydraulic roller tappet
Basic Operating RPM Range 1,800-5,800
Intake Duration at 050 inch Lift 218
Exhaust Duration at 050 inch Lift 228
Duration at 050 inch Lift 218 int./228 exh.
Advertised Intake Duration 279
Advertised Exhaust Duration 287
Advertised Duration 279 int./287 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.492 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.492 in.
Valve Lift with Factory Rocker Arm Ratio 0.492 int./0.492 exh.
Lobe Separation (degrees) 112

I thought with a exh duration of 228 and LSA of 112 that water reversion wouldn't be to big of an issue? Evediently my thinking was not correct?

 

[aldfaa]

Re: 5.7 oil capacity increase?

What is a good cam then that I should install? Boat is a 19' 1996 Celebrity. Used for pleasure/skiing. I do want something that is reliable.

Are the standard vortex heads acceptable for marine use?

 

[Aloysius]

Re: 5.7 oil capacity increase?

Use a relatively mild camshaft. If you want to move the power peak higher in the rpm range, 200-300 rpms or so, you can retard the camshaft. Affects low speed power, but in a boat, this isn't important. with a stock engine and valvetrain, 4500 rpms sustained, 5200-5500 max, is all you're gonna get anyhow. Sure, you can get power to 7000 rpms..for about 20 seconds.

 

[aldfaa]

Re: 5.7 oil capacity increase?

is the mecruiser cam 431 - 811658 which is the stock 350 roller marine cam a better choice then?

 

[zbnutcase]

Re: 5.7 oil capacity increase?

High volume pumps are really for engines that see a lot of starting and stopping, such as delivery vehicles. The stock Chev pump has plenty, running a H/V pump at 4800 just wastes power, wears the dist drive gear, and aerates the oil. Nice thing about boats is no crossmember and or steering to dictate the pan design, and wet sump engines love full length deep pans.

 

[Alpheus]

Re: 5.7 oil capacity increase?

Use a stock truck/RV cam and degree the cam +2 degrees, that will give you low end power. This can be done with a notched timing gear,adjustable gear or a set of Pete Jackson gears. I used the Summit version of the Pete Jackson gears and advanced my cam and it leaps up on plane. Yes you will lose some top end but you wont notice it. My boat tops out at 51 MPH and thats fast enough for me...

 

[Aloysius]

Re: 5.7 oil capacity increase?

is the mecruiser cam 431 - 811658 which is the stock 350 roller marine cam a better choice then?

this cam is 197/205 i/e at 0.050, 109 lobe center, 0.430/0.450 lift. Increase the lift with 1.6:1 rockers if you want. Too many engines are "overcammed".

 

[wca_tim]

Re: 5.7 oil capacity increase?

that would be about perfect and put your peak horsepower at about 5000 rpms, maybe a little higher... You would have to have a little work done on the heads... but not bad and should be fine regarding reversion with factory exhaust...

http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=201&sb=2