[dreambird]

Just wondering if I filled my engine to help with coolant temps and block stiffness, will I see higher oil temps? Just wondering how much of a difference it really makes in a high performance street motor.

[Steve C.]

will I see higher oil temps?

I'm surprised this has not been addressed already.
I personaly never did a before and after check on the oil temp before and after filling so I cannot answer based on actual experiance. Howerver, from my understanding the answer is YES. I base the answer on reading a few statements made on the boards from those involed who have put together many Pontiac builds (proffessionals). That and many years ago while at a seminar with some notable and historic Pontiac persons in attendence the subject came up. From the opinions expressed at the time I personaly put the question to rest and felt confident the answer was yes. But I will say no one seemed to express big concern during the round table discussion.

My recommendation is to purchase a good oil temp guage and monitor it.

[tiacguy]

For years I ran non-filled blocks in my race car which has an oil temp guage. Oil temp was always in the normal range. Two years ago I built a 69-400 short filled engine containing basicaly the same components. Running the same 20-50 Valvoiline race oil. The oil temp was always in the stratosphere. This engine also required frequent bearing changes. I wouldnt even concider running a filled block on the street. IMO.

[Bnick166]

I think you'll find opinions will vary widely on this subject. I posed this same quandry some time ago. Most responces were to monitor engine oil temps and use synthetic oil.
Some say you can do it....others say no way. I' myself....will find out if it can be done or not. The CV-1 build is going to BES in the near future and it's filled to the bottom of the water pump holes. It will be street driven as well. Wish me luck!

[BILTIT]

I run a filled block on the street with a temp gauge and it never gets out of the acceptable temp range. It is interesting to see how quickly the oil can heat/cool though depending on what you are doing with the go pedal.

[Bnick166]

Derek,
How much fill is in your block...short fill (up to the bottom of the top soft plug) or tall fill (to the bottom of the water pump holes)? I think we can safely assume it's not a full fill
(1/2 way up the water pump holes or more).

[PONTIAC DUDE]

I have run quite a few bottom filled blocks. Anything below the center freeze plug shouldn't be an issue. If it is you might source out other issues.

[Johnny406]

My 455 at the machine shop was filled to the bottom of the w/p holes as it was going to go into a Vega wagon drag car. If I had to do it again, I would've only filled it to the center of the middle freezeplug for street use. Oh well...

[BILTIT]

Originally Posted by Bnick166

Derek,
How much fill is in your block...short fill (up to the bottom of the top soft plug) or tall fill (to the bottom of the water pump holes)? I think we can safely assume it's not a full fill
(1/2 way up the water pump holes or more).

Yup,

Sorry should have clarified. It is a short fill to the freeze plugs.

[tom s]

my short deck V motor is short filled.Drive it for 30-40 mile trips each way 2-3 times a month at 2500 to 3000 RPMs.It is a short fill,run mobil 1 10-30.Will put a oil temp gauge on this summer.Tom

[BILTIT]

I have noticed my oil temps start to climb when prolonged rpm above 3500 (highway), but it never gets too hot just warmer than usual.

Could be a carb tune issue too.

[Steve C.]

I use Red Line synthetic oil and I asked them about oil tempature. The response:

A temperature of 240-250°F wouldn't be an issue. Ideally the temperature should be below about 290° to 295°F, for good engine longevity. As you start approaching 300°F seal integrity starts to become marginal, as you approach 325°F the surface hardening will start to soften. The oil will tolerate significantly higher temperatures than the engine and components.

[BILTIT]

I dont think i have ever seen my engine oil over 230F. I run 15w-40 rotella.