Correct Engine Oil

airboat1 · #1 (**permalink**) 12-30-2016, 01:16 PM

I recently purchased an E-M 2005 built cobra with a 351W engine built by a custom shop out of state. It's winter here in upstate New York and I'd like to change the oil to eliminate any potential corrosion while it sits for the next 4 months and have it ready for the summer when it finally gets here.
What is the best blend and grade oil I should use. I only plan to run it in the warm weather so I don't feel I need a dual "w" blend. Also should I use a synthetic blend, full synthetic or non synthetic oil. Can I switch either way on oils without creating a problem? I have no idea what oil is in it, pulling the stick the oil is a light amber. The engine has less than 1500 miles on it. The car also has two side by side Fram Racing filters in it. I have read quite a bit on oils and still would like someone's opinion.

Thanks,

Steve

mikeinatlanta · #2 (**permalink**) 12-30-2016, 05:17 PM

Two choices. Read a thousand unsubstantiated opinions on an internet forum or start doing some research to learn what's really going on.
I'll help you start down the second path.
https://bobistheoilguy.com/motor-oil-101/

Dwight · #3 (**permalink**) 12-30-2016, 05:35 PM

You want a thin oil when you first start the motor and one that thicken up a little when the motor reaches operating temperature. Hence 5-30w

If you motor was build with tight bearing tolerance you would need a thin oil. A motor with loose (race) tolerance would need a thick oil.

Dwight

undy · #4 (**permalink**) 12-30-2016, 05:40 PM

You need to know whether you have a flat tappet or roller cam before you select which oil. If you have a flat tappet you'll need to run an oil with a good amount of zinc otherwise cam lobes seem to go away.
I'll bow to others as to what specific oil they recommend.

airboat1 · #5 (**permalink**) 12-30-2016, 06:05 PM

I know it has a roller cam. I'll get moving on the link Mike.

Thanks

spdbrake · #6 (**permalink**) 12-30-2016, 06:07 PM

I second Mike in ATL advice.

bobcowan · #7 (**permalink**) 12-30-2016, 06:07 PM

Always use a multi-viscosity oil in a street car.

Engine Oil – Synthetic? Dino? So Confusing. – Racing the Exocet

Engine Oil – Viscosity – Racing the Exocet

mln385 · #8 (**permalink**) 12-31-2016, 03:33 AM

If you know who the engine builder was give them a call and ask what they recommend.
They know what materials they use and what they need for proper lubrication.

eschaider · #9 (**permalink**) 12-31-2016, 12:32 PM

Quote:

Originally Posted by airboat1

I recently purchased an E-M 2005 built cobra with a 351W engine built by a custom shop out of state. It's winter here in upstate New York and I'd like to change the oil to eliminate any potential corrosion while it sits for the next 4 months and have it ready for the summer when it finally gets here.

I wouldn't worry about any corrosion, Steve. As luck would have it, absent significant engine failures, the oil is inside the engine and once the engine has been started the entire interior is coated with an oil finish. Moreover, unless you disassemble and wash the engine parts it is essentially unheard of for the oil finished components inside the engine to rust over a winter — even if the vehicle were left exposed to the elements outdoors.

Quote:

Originally Posted by airboat1

What is the best blend and grade oil I should use. I only plan to run it in the warm weather so I don't feel I need a dual "w" blend. Also should I use a synthetic blend, full synthetic or non synthetic oil. Can I switch either way on oils without creating a problem? I have no idea what oil is in it, pulling the stick the oil is a light amber. The engine has less than 1500 miles on it. The car also has two side by side Fram Racing filters in it. I have read quite a bit on oils and still would like someone's opinion.

Thanks,

Steve

The best thing to do is to ask the builder who built your engine what oil he wants you to use. He is the only one who knows, with certainty, how your engine was assembled and therefore what it will require.

Ed

Texasdoc · #10 (**permalink**) 12-31-2016, 02:40 PM

Quote:

Originally Posted by airboat1

I only plan to run it in the warm weather so I don't feel I need a dual "w" blend.

You should run a "W" blend oil. It's not just the ambient temperature that you need to worry about. It is the difference between the ambient temp and operating temp. Even if it is 100 degrees outside, a straight weight oil will be too thick to adequately flow if it is the correct weight/thickness to provide the right lubrication at operating temp.

Bartruff1 · #11 (**permalink**) 12-31-2016, 03:26 PM

I always ask the kid a " Quick Lube " ......after all he is the professional...

He says " oil is oil "....after some 2 million miles , in a variety of cars with zero oil related problems over 60 years...

I think he is right .

Even if he is getting old.

Shootnride · #12 (**permalink**) 12-31-2016, 03:59 PM

Joe Gibbs/Driven Racing Oils has a variety of oils designed for specific applications. They have a good reputation among many of the well known engine builders. You may want to check out their website. Below is a link to their explanation about choosing the correct oil for your vehicle.

Choosing The Proper Oil Type | Driven Racing Oil

Ted

jmimac351 · #13 (**permalink**) 12-31-2016, 07:11 PM

Steve,

I've looked at the BobOilGuy site a fair amount. I've noticed the viscosities of diesel oil (5w40 and 15w40 - 5w cranks better in winter). Think about the pressures heavy duty diesel engines see and the oil weight they use... I've noticed that the Ford 5.0 Coyote motor takes a 5w20 (for CAFE standards), but if you have the Track Pack mustang, it says 5w50 (I guess for track use). I think any clean oil is better than any dirty oil. I own race cars, street cars that I drive hard, currently own an EcoBoost (Turbo) F150 and rather than get caught up in this stuff (as many on the Bob site do) I've come to a few conclusions:

If I'm picking one shotgun to own, it's a 12ga.

If I'm picking one oil to use for any weather, in all of my vehicles, it's 10w30.

If I know I'm driving the car at the track, I might like to pour in 10w40 (at Sebring in the summer).

If I have a pushrod motor with flat tappet cam, I'd run an oil with a lot of zinc. Those have been created for a reason.

Otherwise, the only oil related problems I've ever heard about seem related to pressure, not type or brand.

Good luck.

RET_COP · #14 (**permalink**) 12-31-2016, 08:06 PM

I use Driven oil HR series [HR for Hot Rods]( old Joe Gibbs) it has all the good ingredients plus it clings to metal parts in storage. I'm sure Brad Penn and Amsoil etc. are good also But driven oil has a lot of performance followers. Don't worry about the price you only pay once a year for it. As for viscosity 10-40 works for me, not too heavy not too light. I have in depth reasons for using the 40 wt. Oil is a hot topic

Kobura · #15 (**permalink**) 12-31-2016, 08:35 PM

When I got my new Backdraft, the speedometer had been replaced because it was not working correctly. The tachometer was not a matching unit and so I replaced it. I was surprised at how easy it was to do so. It was also clear to me that the speedometer/odometer could also be easily replaced. Thus, I wonder if many of the buyers of Cobras are suspicious of the (apparently) low number of miles that their cars have in spite of the how many years the cars have been on the road.