[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.

[StalkerStang]

I use 10w30 Castrol Syntec in my 90. The motor doesn't have very many miles on it and I run it pretty damn hard at the track, never burns oil, and its usually close to the same color coming out as it did going in.

Pretty much anything Synthetic is better, whatever brand, Valvoline, Mobil 1, Castrol, Royal Purple. But I would definatly stick to 10w30 like Ford Racing said.

[fine89lx]

I have low mileage on my engine and only race it once a year. I tried Amsoil this year (2006) Its 10W30. It has stayed very clean and I have noticed tthe it didnt go very far down the dipstick., unlike the Mobil 1. It got dirtier faster and i was down about 1/2 quart by the end of the weekend. Up here Amsoil is about $10.00 a quart..whic h is not to bad....Just my experience

[hofiveo]

I use Schaeffer Schaeffer's Micron Moly® Racing Oil SAE 30W-50. I have a 2001 Ford F-350 Crew Cab 7.3 Turbo. We average 40,000 - 50,000 miles a year pulling a 32 foot gooseneck trailer. we weigh total truck/trailer 25,000 lbs roughly. We started using it a few years ago and go an average of 13,500 miles between oil changes(per oil analysis) so i started using there race oil above in my mustang and have 100 or so runs and send oil sample in for analysis and they say keep going. go here Bob Is The Oil Guy: Viewing list of forums to learn about oil and other lubricants. BlackStone lab is where i send oil for analysis. I think i use this insted Schaeffer Oil | Supreme 7000 Synthetic Racing Oil i am not sure now. i will go to my shop and find out tomorrow. I am pretty sure it is the 20W-50.

[93mustang]

I've been using Valvoline VR-1 10w30 racing oil.
Works great!

[andrewsg]

I use amsoil 20w-50 full synthetic in both my thumper car and my nitrous fed car.

Both vehicles have been running said oil for over 50k each and havent had one issue.

Before I used the 20w50.. every 30k, the thumper car was getting new bearings anyway -- I'm anal and was using race pieces. Now with the same race pieces, I took everything apart at 40k and there is no wear at all.. compared to when I was using 10w30 and at 30k there was noticable wear.

Go figure.

[don_w]

I run 20W-50 Lucas synthetic in mine.

[Asheron2]

I like to run Delo-400 in my vehicles its got some zinc stuff in it thats very good for antiwear, the same stuff thats in the STP. All i know is that i work in the power industry and we prelube our couple million dollar turbines with STP and then fill them up with Delo 400