Oil change
 

What is a good weight oil for the hot weather in Arizona, and what is a brand of synthetic oil ?

Skully,
Do you have a flat tappet or roller cam?

I use 10W30 whatever is on sale and change every 3000 miles which is about every 9 months. 45,000 miles no significant compression loss on leak down test. Went through a period of synthetic oil but still changes every 3000 miles. Waste of money and the thin oil seems to seep out on my garage floor. Unless you race a lot, just be kind to your motor and give it new oil....frequently. And check it a lot.

AZ Bob

It doesn't hurt to use some additive that contains phosphorus and other lubricants that help the oil. I use Valvoline 20W50 with BG Products additive. Change about every 3000 miles.

Check with your engine builder for their input as 1 big consideration. Look at the dino VS synthetic points related to your camshaft type, no synth. on a flat tappet cam unless it is a special blend with lots of additives-race only type.

Think about your area for max temp it will run. Use a oil light enough to provide start up oiling but not so thin you loose pressure at hot idle to point of danger. You will of course see a pressure drop at hot idle but must not drop below 20 to 25 PSI for my tastes. Too thick and you bypass filtering on cold start up and risk bursting filters and so on. I always warm up my engine before loading it and zinging the throttle is a no no until temp is stable.

High oil pressure is more old school that just gives HP away but I still lean that way, hell I am old so that's OK. I like to see 10 PSI for every 1K RPM with idle pressure of 30 or more ideal. It all depends on how the clearances in your engine were set up and what kind of cam and valve spring pressures you are running. I also try to avoid prolonged idle at same RPM. I burp throttle a couple hundred RPM if idle very long just to splash oil all areas. I run a fairly larger solid roller cam and valve-train so low RPM oiling is not what everything else was designed for.

If engine is a bone stock cast iron donor ...... who cares what oil or type cause it was made to live a the worst the public can dish out.

The engine was built by FordManDan , it is a 306 with aluminum heads , roller cam, the person I bought it from used 20 50 w Mobil 1. It has a FL1A Ford filter, also how often do you change the gas filter on a electric fuel pump.

Oil is a tough subject. Partly because the oil makers keep the info close to the vest, and partly because there's a lot of mis-information on the web. Here's some basic facts about engine oil:

1. Viscosity:

You need a "heavy" enough oil to maintain proper pressure in all situations. What that is, exactly, varies from engine to engine. Anything mor than about 50psi is more than necessary, and wastes energy producing the pressure.

Too thick can wear on the drive mechanism, and shear gear pins. It will not produce appreciably higher pressures, because the pump has an integral pressure release valve.

Oil "thickness", "weight", and viscosity are usually displayed as two numbers; as in 10W-40.

The 10W means the oil will have the viscosity of a 10 weight oil when it's cold. The W stands for Winter.

The 40 means it will have the viscosity of 40 when a 40 oil is up to operating temp. That does not mean it will have a viscosity of 40 when hot.

I use a 10W-40 oil and never have trouble maintaining 45-50PSI in all situations, even when the oil temp rises to 240*.

2. Synthetic Oils

A true synthetic starts with a PAO base stock. There are no dino oils in it. AFAIK, there are only 4 on the market: Red Line, Royal Purple, Amsoil, and a nother one I can never remember.

Other so called synthetic oils start with dino oil, and is then refined enough to meet the specified performance standards of a synthetic oil. It's a trick of lawyers and marketing. Most people don't know the differance.

Mobile 1 is NOT a true synthetic. It's a fine oil, and will work just fine in most situations. But it's not a true synthetic, and probably not any better than QUaker State, Penzoil, Castrol, etc. If the price is comperable, don't be afraid to use it.

True synthetics have two big advantages. They are more heat resistant. They withstand higher temps for longer durations without breaking down. 240*for 30 minutes for a true synthetic is not a big deal. They also last a lot longer than dino based oils. A 10K mile drain interval for a DD is pretty reasonable.

3. Change intervals.

3000 miles is OK if you have an old dirty engine, or use leaded fuel. The only people who routinly still recommend changes that often either sell oil or oil changes. Many people change it that often because that's what grandpa did, and he was a mechanic for 30 years. Those people have not kept up with modern technology. And some people use cheap wally world oil and change every 3K miles because it helps them sleep at night; and that's OK, to.

I use Royal Purple, and change it about twice a year. I race with leaded fuel and beat on it pretty hard. I also use RP in my DD, and change it every 10K miles.

4. Flat tappet cams

In the past, oil had plenty of ZDDP as an anti-wear additive. Because of emissions reg, most of it was pretty much eliminated. Even diesel oils have decrease the ZDDP by about 25%. This is one of the facters that contributes to increased lifter and lobe wear. Comp Cams has an excellent white paper on this subject. If you're interested, be sure and read that.

There are a couple of additives on the market that will increase ZDDP to previous levels. Some racing oils also have higher levels. But you can't use them on any vehicle that has a cat.

After reading the white paper from comp cams, I wouldn't build an engine with flat tappets.


So, here's my general recommendation for most Cobra owners.
1. Use a decent Dino oil for street use, and a true synthetic for racing.
2. If you have a flat tappet cam, add some extra ZDDP
3. Change it once a year for steet use, and 2-3 times a year for occasional track use.
4. Use the lowest viscosity that will produce the proper oil pressure in all situations. a 5W-30 is probably right for most people.

But, that's just my opinion. I could be wrong.

10 w 40, unless the motor runs really hot.

Mobil One is fine but regular I prefer regular Valvoline and change it once in a while. :3DSMILE:

Most manufactures recomment every 30k on the fuel filter, more often if you're getting bad fuel.

The ZDDP level in Redline is 1,200 PPM (which is why there is no sunburst symbol on the container). Mobil1 and others is 800 PPM.

Use the lowest viscosity that gives you the pressure you desire.

Bob

15-50 Mobil 1 synthetic every 2500-3000 after that important break in period. This way you can drink it because it is not real dirty yet. Good for the bonesand tastes like old coffee.:rolleyes:

Flat tappet use Brad Penn racing oil 50/50 mix of 10W30 with 20W50 equals
15W40. Great stuff, it was the old Kendall refinery. They use to refer to Kendall oil as "liquid spinach".