BRAVEHEART

Has anyone used synthetic oil in merc racing 525 efi's and if so, what was the result?

mjb

Be careful with synthetic oil in these engines. This is a much debated topic and there are strong opinions on each side of the argument....but there are many engine builders who claim that you should not use synthetic oil in an engine with a hydraulic, roller cam. The spring pressures on hydraulic cams are relatively light compared to solid cams. When using roller lifters, the synthetic oil is so good(slipery) that the roller can actually slide across the cam lobe rather that roll. The higher spring pressures with solid cams eliminate this problem. Is it true??? There are some in the know that says this is an old wives tale and others that swear they have seen it happen. I use a straight 40 weight valvoline just to be on the safe side.

Sonic30ss

I don't buy the argument about roller cams and synthetic oil. In my experiance, I have had nothing but good come from using Mobil 1 (various viscositys, but 15-50 in the hi-po stuff)in everything, 96 Jeep 230,000 mi on a roller cam engine still sounds and runs like new(with my 16 year old driving it ), 65 race hemi big roller cam, custom 114cid shovelhead roller cam, all 4 motors that have been in the boat roller cams, never a cam issue, all my work trucks,wifes car etc....
The guy who does my machine work has told me on his dyno they've seen 5 hp and cooler oil temps with synthetic
I would not use anything else but synthetic.
BTW- those motors sounded pretty good yesterday, you were at Claudios right?

Do a search for a thread by Hydrocruiser on synthetic oils, it will keep you busy for a while

Raylar

I am sure Mercury Racing has done a lot of syntheitic oil tsting in their motors in a lot of high abuse/use testing.
Ask Mercury Racing and Follow their recommendations on the oil to use. Just my thoughts.

Ray @ Raylar

BRAVEHEART

thanks for the response.. it stands to reason Merc Racing would only recommend their own oil products. I've been told by independant performance guru's that synth is the only way to go. I guess I have to give it a try and see what happens..

BRAVEHEART

hey Sonic30ss, Yup I was across the pond at Claudios.. Were you directly across from me?

OL40SVX

I see your on here too!!!!!!!
The Gladiator has it in it now and mobil 1 is going back in. Phil at lip ship seems to only use mobli 1 so were sticking with it. Ive heard nothing but good. Go for it.

Danny

lucky strike

iTrader: (1)

My 525's are under warranty. I was told by Mercury to use their oil & filter or no warranty ! So thats what I use.

Sonic30ss

That was me

BRAVEHEART

my 525's now have over 300 hours! So I figure what the hell, If synth oil makes em blow it's time for more cubic inches anyway! Anyone know the Amsoil equivilent of Kendall racing straight 40 weight?