has any one ever experienced a 30* increase in oil temp and excessive blow by when switching from synthetic to regular motor oil? Water temp remained the same. Am I just burning off the remains of the synthetic???
Thanks
Dan

I would buy the temps going up a bit. The blow by seems odd... Isnt non synthetic oil ussually less likely to do that?

Jon

what oils are we talking about??

switched from Royal Purple racing 40 to Valvoline 50 wt racing

Dan,
I went the other way..from Valvoline 20-50 to the Royal Purple.. didnt see any changes that I can relate. I see oil temps from the pan around 260/270 when running hard..

Dick

WHY...go back...unless u change it a lot more often due to price??? the Val **** has a lot more zink content for metal to metal.

I switched for several reasons...not available..breaking in new distrib gear..temps were too low.. never got hotter then 200 even when running hard..mostly 150 or so.
Now temp is 230 at 3500-4 rpm
pressure is good
water 150-160.
Also timing was way advanced which would cause hotter temps???? Also may have over filled it...12 qt pan..I put in 12 qts..usually run 10
Backed it down to 35* after a short run. Power is still good. What conserns me is the blow by

actually retarding the timing can account for higher tmps. and merc runs 190 deg for oil..

Well
It was the oil I guess
Re placed the Valv with more Royal Purple and all is right with the world again. I cant figure this one out...but who cares???

Thanks for the input fellas
Dan

I too used Valvoline once and had major oil consuption...switched back and all was fine.