mountainmotor

Many probably know this but modern conventional mineral oil is some pretty good stuff.Especially when up to operating temperature.Some of the Exotic oils and additives can actually decrease power because the average performance motor does not have high enough piston ring tension to seal the cylinders when some of the race synthetics are used.About 5 years ago I saw first hand a 10hp gain when Klotz synthetic race oil was replaced with Castrol 20/50 WT in a 750 cc 4 stroke Suzuki M/C Race motor with 12.5 compression

Our older manual transmissions are a different story.The slicker the better.Climate permitting,80/90 GL5 gear oil works very well with a couple of tubes of BG Extreme Pressure Concentrate.I have had very good luck with this stuff and you can feel the difference with it in the trans.I highly recommend it!

I can attest to a local T5 running 5/30 synthetic motor oil in it behind a hot 383 in place of the factory Type III Automatic Transmission fluid .ATF is just a highly refined hydraulic fluid and equivalent of a 20/wt as far as cold pour is concerned.5 years of this and still working well.Anything will help a bearing load better than ATF it seems.It recieves a yearly change.Nothing will strenghthen the mainshafts ect though.Same is going on with a local 6spd in a late model Vette.He though changes to a 15/50wt Synthetic in the summer months.3 yrs of this.This is one slick shifting trasmission!

I have heard from many that the use of Type F in a GM 350/400 transmission will make for firmer shifts without any adverse affect towards longetivity.I have not done this my self so cannot confirm or suggest this.

There are many products out as alternatives to old style gear oil.If bearing clearance as far as wear goes allow a lighter than above GL5 gear oil and additive can be used.I will for example be using Bel Ray light gear oil in my T10.Works like 80 wt and cold pour like 30 weight.It is a product designed for and used in Motorcycles with separate gearboxes from motors.

Motorcycles have long been the ultimate"acid" test for motor oil because the modern 4 stroke engines must be a gear oil and handle a 13 thousand RPM motor.In actuality some of the mineral based M/C oils available would be a better choice for some Vettes that are stored for longer periods between drives due to the additional anti oxidation and anti corrosion additives.Some might want to take the time to surf and see what is available.Might be something out there just for you.Mobile has a complete line of MC oils as well as others including the very good Yamaha line of oils.

Motor oils have come a long way since the multi weight was a blend of Number 2 diesel Fuel and bright stock to make it look pretty.

73-454

Stick to a name brand oil, changed the oil and filter every 3,000 miles or at least twice a year and forget abought all the snake oils. Remember you can't out-smart the Pros.

Neo Fender

In Richard Newtons book, "How to Restore and Modify Your Corvette 1968-1982" He mentions doing this and also says that Ford enginneers favored firmer shifting automatic transmissions as opposed to GM engineers who preferred smoother shifting trannys.

The only problem I see is that just draining the Dexron out of the pan is NOT enough. You'll have to empty out the torque converter as well.