I have an '04 SE and a '06Ultra.I run V-Twin an the SE and it quieted down somewhat and the Ultra is a 95" with 251 camshaft.I recently put 20w50 Amsoil in it along with Amsoil gearlube in the gearbox.I know that the topend is quieter and trans is smoother..
I had a pair of 454's in a 35 lightning redone with Crane 741 cam and ran M1 for a long time with no problems.Probably was a lifter problem with this HP500 engine.I have heard the rants about running synthetic in roller/high lift cams but would really like to see proof of failure.

Why Cams fail:

1. Lobe wearA) Incorrect break-in lubricant.
Use only the Moly Paste, Part Number 99002

B) Correct break-in procedure.
After the correct break-in lubricant is applied to the cam and lifters, fill the crankcase with fresh non-synthetic oil...such as Valvoline VR-1 20W-50..then synthetic at the first change... Prime the oil system with a priming tool and an electric drill so that all oil passages and the oil filter are full of oil. Pre-set the ignition timing and prime the fuel system. Fill the cooling system. Start the engine. The engine should start quickly and run between 1500 and 3000 rpm.

C) Spring pressure
Normal recommended spring seat pressure for most mild street-type flat tappet cams is between 85 to 105 lbs. More radical street and race applications may use valve spring seat pressure between 105 to 130 lbs. For street hydraulic roller cams, seat pressure should range from 105 to 140 lb. Spring seat pressure for mechanical street roller cams should not exceed 150 lb. Race roller cams with high lift and spring pressure are not recommended for recreational use, because of a lack of oil splash onto the cam at low speed running to help cool the cam and lubricate the lifters. This high spring pressure causes the heat created at the cam to be transferred to the roller wheel, resulting in its early failure.

D) Mechanical interference.
There are many factors that can cause mechanical interference.

(1a) Spring coil bind: This is when all of the coils of the spring (outside, inside or flat damper) contact each other before the full lift of the valve. We recommend that the spring you are using be capable of traveling at least .060" more than the valve lift of the cam from its assembled height.

(2) Retainer to seal/ valve guide boss interference. You need at least .060" clearance between the bottom of the retainer and the seal or the top of the valve guide when the valve is at full lift.

(3) Valve to piston interference: this occurs when a change in cam specs. (i.e.; lift, duration or centerline) is enough to cause this mechanical interference. Also: increased valve size, surfacing the block and/or cylinder head may cause this problem. If you have any doubt, piston to valve clearance should be checked. Minimum recommended clearance: .080" intake and .100" exhaust.

(4) Rocker arm slot to stud interference: As you increase valve lift, the rocker arm swings farther on its axis. Therefore the slot in the bottom of the rocker arm may run out of travel, and the end of the slot will contact the stud and stop the movement of the rocker arm. The slot in the rocker arm must be able to travel at least .060" more than the full lift of the valve. Some engine families, like small block Chevrolet, have stamped steel rocker arms available in long and extra long slot versions for this purpose.

2) Distributor gear wear.The main cause for distributor gear wear is the use of high volume or high-pressure oil pumps. We don?t recommend the use of these types of oil pumps. If you do run these types of oil pumps, you can expect short life of the cam and distributor gears, especially for low speed running, in street type applications. If you must run these types of oil pumps, you can increase the life of the gears by adding more oil flow over the gear area to help cool off the point of contact.

3) Camshaft end play. Some engines have a thrust plate to control the forward and backward movement of the cam. The recommended end play on these types of engines is between .003" to .008". Many factors may cause this end play to be changed.

4) Broken dowel pins or keys.
The dowel pin or Woodruff key does not drive the cam; the torque of the timing gear bolt, or bolts, against the front of the cam drives the cam.

5) Broken camA broken cam is usually caused by the cam being hit by a connecting rod, or other rotating parts of the engine coming loose and hitting the cam. When this happens, the cam will usually break in more than two-pieces. Sometimes the cam will break in two pieces after a short time of use because of a crack or fracture in the cam due to rough handling during shipping, or some time before installation. If a cam becomes cracked or fractured due to rough handling, it will generally not be straight.

I spoke with a high end builder and he agreed...high and lift are racing cams that need high RPM's for good oil flow.

Using the set-up for extended periods at low RPM causes oil starvation and flat topping.

Makes sense to me.

GM doesn't spend the extra $$ on mobil 1 for the corvettes factory fill because it isn't better.

My quick story of why I like Mobil 1. I bought a bike that had been drag raced. The prev. owner installed a heavy duty clutch, ran it a couple times then quit due to medical reasons. I got it after it sat a couple years. I drained the water from the gas tank, cleaned the carbs, and changed the oil with conventional oil. The clutch slipped. Put a couple hundred miles on it with no change. I remembered he had mentioned running Mobil 1 (a motorcycle clutch is oil cooled). I took the clutch apart and cleaned the friction plates with brake clean. Clutch grabbed extremely hard from then on. The Mobil 1 was making the plates too slippery even after changing the oil to conventional. Seems like a good lubricant to me!

Does the Valvoline VR-1 20w50 have any detergent properties ?Being that it's a racing oil I'm thinking that it doesn't.I don't have a problem with that as none of my engines have ever had a problem with sludge buildup......

They claim the oil reduces friction thereby decreasing deposiits...fyi ZDDP 1300 ppm

The Valvoline VR-1 Racing Motor Oil
• The #1 selling Racing Oil of all time and race track proven.
• Protects against high-temperature deposits for a cleaner engine.
• ZDDP additive provides tough anti-wear protection.
• Enhanced with fricition modifier to improve horsepower.
• Formulated with enhanced anti-foam system.

Here is the spec sheet..

http://www.valvoline.com/products/VR...otor%20Oil.pdf

What oil would you guys rec for merc 525 engines??

I was just treated to an excellent presentation by Bill Maxwell of Exxon/Mobil, who is considered by many to be "the father of Mobil One". His experience goes back over 40 years, including some mistakes that were made along the way. Amazing stories. The key points of his talk:

1. Rather than sift through tons of crude oil looking for the molecule(s) you want, and having to settle for some you don't want as well, synthetics give you the ability to create only the molecule(s) you want - and nothing else.
2. Mobil One has learned (sometimes the hard way) that additives that work in mineral-based oils rarely work the same way (if at all!) in a synthetic. Synthetics require their own, highly-specialized additive packages. Latecomers to the synthetic game are still learning this lesson.
3. For marine use, there is no better oil in the world than Mobil One V-Twin 20w50. It is basically the toughest oil on the planet, and perfectly suited for hard-working marine engines.
4. Racing oils such as Red Line and Royal Purple can be deadly to engines (and outdrives!) that do not see extended periods of high temperature (230+ oil temp), or are stored for any period of time (even just a few weeks). These are almost pure ester-based oils, and any water or condensation present in them will cause the esters to break down into their original components - alcohol and ACID!
5. Mobil One SHC (Sythetic HydroCarbon) grease is fine for any marine application, and is waterproof.
6. Mobil One oil filters are manufactured (by Champion filters) to higher standards than even OEM filters in terms of both filtration ability AND minimal flow restriction.

I'm a believer. I've seen Mobil One 75w90 come out of a transmission intact, even after it got so hot that it melted the solder out of a scavenge screen.

What type of synthetic gear lube are you talking about? And were do you get it.

I will have to change drive oil shortly. I have been using Royal Purple 75w-90. Is Mobil 1 synthetic drive oil better? I usually just change once per season.