[93mustang]

I just put a Ford Racing Gt-40 345 Horse Power Crate Engine in my 93 Gt Mustang. My car is street legal, not a daily driver, mainly used for drag racing and some once and while street driving.
I know everyone likes synthetics, Mobil 1 especially. But when you race , you should change your oil very often. This could get quite expensive if you where to use synthetics!!! And I do change my oil every 10-20 rounds.
On my old 302, that had 126,000 miles on it, I used Valvoline 10w-40 Max-Life non synthetic with Lucas Oil oil stabilzer. 3-1/2 qts. Valvoline to 1- qt Lucas. That combo seemed to work great. The Lucas Oil stabilizer seemed to keeep the oil from breaking down as fast.
Ford Racing said to run 10w-30 for the 500 mile break in period to let the rings seat. I asked what to run after that and I told them that I'd be drag racing and they said 10w-30. I asked synthetic or mineral. They said mineral. My mechanic who is a former mustang racer and current engine builder for 30 years said he like a heavier weight mineral oil like 10w-40 in brands Amalie, Valvoline. He use to run 20w-50 in his cars, but he wouldn't go that heavy for this motor.
What do you guys think? It's a new engine and I just want to run what is best.
I have e-mailed Valvoline, Lucas Oil, Castrol, and Amalie with this question. I'll post their replys when i get them.
Thanks!

[93mustang]

Well, here's some reccomendations from some oil companies that I contacted.

From VALVOLINE
The best oil we have for your application and usage per your email is
SynPower 10W30 engine oil. Change it every 3 months for maximum
protection

From LUCAS OIL
I WOULD RECOMMEND USING OUR RACING OIL IT IS REALLY GOOD FOR RACING
ENGINES
WE USE IT ON ALL OUR RACING CARS.. I WOULD RECOMMEND USING THE 20/50
REGULAR
RACING OIL WITH A QT OF OIL STABILIZER TO REDUCE WEAR ON THE ENGINE. DO
YOU
HAVE A BIGER OIL PAN?

I HAVE A 4.6 ENGINE DOHC WITH NOS ON MY 01 MUSTANG KIKIN CLOSE TO 390
HP AND
IT REALLY WORKS GREAT ON THAT....

From CASTROL
Thank you for contacting Castrol North America.

Castrol recommends the use of Castrol SYNTEC full-synthetic motor oil
in
racing applications. Many professional drivers, whose engines
experience
extreme wear, use SYNTEC.

In addition, Castrol SYNTEC has an excellent detergent/dispersant
system,
which provides superior performance in maintaining engine cleanliness
and
helping to prevent build-up of deposits within the engine. It also
contains
patented stabilizers that interact with harmful pollutants more
effectively
than conventional oils. In doing so, they seek out combustion
by-products
and other corrosive particles and hold them in suspension, while
maintaining
engine cleanliness. SYNTEC neutralizes or stabilizes corrosive effects
and
provides deposit formation protection, resulting in a cleaner running
engine, thus reducing wear and helping to extend engine life.

Castrol SYNTEC 5w-50, 10w-40, 5w-50 and 20w-50 have been proven with
excellent protection and performance in NASCAR, Pro Stock NHRA Drag
Racing,
IMSA track and USAC Racing. Here are just a few of the professional
racers
who use Castrol Products, John Force and Tony Pedregon (NHRA) Ralf
Shumacher
and Juan Pablo Montoya (F1) Ezra Lusk and James Stewart (AMA pro
racing) and
Colin Edward and Tadayuki Okada (WSBK).

Please recognize Castrol cannot supply grade recommendations for
modified
engines.

From ROYAL PURPLE
You engine takes a 5w30 or 10w30 which is spec-ed from Ford. We would recommend the same weight and there is no difference in weight of a synthetic or non-synthetic. For a racing style motor though we would recommend our XPR series oil which is Extreme Performance/ Racing Oil. The weight you would run is XPR 5w30. This will give you better protection as well as freeing up a few more horses. You will want to break the engine in on a conventional oil for about 500 to 1,000 miles before putting our product in you engine. Our film strength will not allow the rings to seat as fast and you will burn oil for some time if you do not allow them to seat.

Feel free to give some of your reccomendations.

[Rogertaddei]

Royal purple would do the work!

[supercharged302]

I would run royal purple

[madmaxx69]

I run 10 w 30 MotorCraft blended oil in my twin turbo car. $3.00 a quart at autozone, I change it every 40 passes. Comes out as clean as it went in but E85 is not as dirty as gasoline

[89BlkNotch]

in my opinion and after lab testing the oils, i would use kendall, but thats hard to find so then pennzoil, castrol and valvoline sucked in lab testing, they broke down very early due to heat, pennzoil and kendall lasted, those are the only two oils i run in my cars street or racing doesnt matter, for you i would recommend 10W-30 or 10W-40 from kendall, pennzoil, and royal purple, all three are great oils, i am still a fan of mineral oil not synthetics

[Brutal Metal]

Can you furnish us these lab tests 89BlkNotch?
And in the first sentence you say Pennzoil sucked in the tests, then the 2nd sentence you say it ones of the oils you run in your cars? And what type of Valvoline was tested? SynPower is good oil, lots of the speed shops in South Florida use it..

[89BlkNotch]

sorry i had a few grammar errors my commas are all out of place, pennzoil is good, but i dont have the results i did this test a few years ago in college for a mechanical engineering course, im not saying things havent changed, but from what i have seen with my own two eyes those are the only oils i will run, i mean all oils have to meet APSI specs so all all is kinda the same what changes it is the signature additives each manufacturer puts in

[Brutal Metal]

From my experiece as well as other guys that tear these motors down on a regular basis is conventional oil tends to create more sludge at the bottom of the pan, you can take a spatula and fill it up. Bearing wear is also more extreme, synthetics are superior in these 2 areas, and most of the signature additives you mentioned are detergents with the purpose of decreasing sludge.

[86lxNitroRacer]

Castrol Syntec! Great Oil, Great Company. Or check out their new EDGE line, high end oil. Look for it coming up in racing soon.

[RLG34750]

I run royal purple 30w

since i am on the bottle (n2o) i change the oil after 3-4 bottles