Actually, since it is closed cooling, I pick it up at the raw water side of the heat exchanger. They bouce a bit but they are mechanical not electrical.

I did a search on Oil Temps and Laz Mesa indicated he runs some race (marine) engines with very similar temps all season long.

What are your opinions on fattening up the carbs? Could the 10% ethanol the socialists in my state are now mandating be a source of more heat? I never upsized my jets for that.

Not directly. I have senders in the pans and in the Eickert/Hardin T-stat housings (Before cooler). I have switched them back and forth and found them to be nearly identical (10 degrees cooler in T-stat).

I tend to like them in the pan which is where they are now. I was told by my Marine Engine mentor years ago that the pan is where it counts.

Richening probably won't affect much.

In the pan is good but I am curious do you know what oil temp is feeding in after the cooler? 270 may be a little warm in the pan but if your feeding cool oil to the bearings you are probably OK in my opinion. I like or prefer to know what I am feeding the bearings. I have mine setup with two senders one before and one after that I can switch between and view from one gauge. I am no expert for sure just my preference. I think it would be good to know how much your coolers are actually cooling. If they have 200 degree stats in oil coolers then 270 coming off th emotor after heat load may be normal at high loads. Some old chevy books say 300 in the pan is the limit and they are also more concerned with the return oil temp.

good suggestion. I will add the second after cooler sender to my "winter to do list". I want to say the t-stats are set to open at 215 degrees to ensure moisture cook off.

I also plan to use my infra red heat monitor this weekend to confirm the gauges are correct.

I have struggled with proper oil temps myself. Lots of different opinions or preferences out there. I run a 5x19 Dan Olsen cooler as they list it. Oil runs a little warm off the motor but I never see much over 240 return WOT. Still thinking of going to a bigger cooler next build up since I have t-stat for oil. I would watch the infrared readings as material and paint will change readings. A good tool just not super accurate unless you consider emissivity of material. You may want to add a mechanical gauge just for reference if it is not too much trouble. Good thing we all enjoy this stuff or it would drive us all crazy. :drink:
I always wonder if anybody knows what there tow vehicle oil temps run when towing up a hill. :eek:

I'd try richening the mixture. It's easy and cheap, why not. Go 2 jet sizes on all barrels. It made a noticable difference on mine.

Did you fatten it up specifically to drop temps or because the ethanol issue?

Teague on tech (Powerboat) had a recommendation for the ethanol upsizing but I couldn't find it. 2 sizes sounds right. My plug readings are good but I would choose less heat for a safety margin.

I have Nickerson Carbs. Dean told me I have to let go of my notion that each engine needs identical tuning. In my mind they are carbon copies. They were within 2 hp all the way to 6500 RPM but they do sit in the bilge differently, get different air flow and temps and may not have carbon copy fuel flow rates. It is an emotional issue at this point.:cool:

Update
 

The 2 size jet increase (96 and 100)did give me a drop in temp. It is hard to read the gauges to this level but I will say it appears to be 6-8 degrees lower now. I was testing props today and made several long runs at 6500 rpm and never broke over 270 at the gauge.

I used the infrared temp gun on the oil pans, filters and T-stats and it is telling me 30 degrees lower than the gauges read. Can they be off that much? They are the Livorsi units that came with the boat.


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But what kind of performance did you lose for those 6 degrees?