oil temps running hot with vortec head

[badbug]

I have flat top pistons in 454 .030 over, mark 4, with 1999 vortec heads with correct fel pro gasket . Engine temps run 160 and stays there but oil temps will continue to climb while cruising at 60 mph untill i have to slow down and let oil temp come down.I have a large oil cooler from tyler crocket and have been running it for quite a while with other engines without this problem. I thought the engine might be lean so i richened it way up to the point it slowed down 5 mph and oil temps continued to rise. I jetted it back down and mph came back. It is in a 22 ft v-hull stryker, bravo one. Cam is crane 550-570 lift hydraulic,114 lobe center, edelbrock performer intake,.Other engine didnt do this last year. It was a 30 over 454 with regular 781 heads at 9,5-1 comp with same cam. Carb is 750 4779 holley. Jets are 72-82 with primary power valve. Digital 6 ignition. What gives.. I should be able to run this thing pretty hard without oil temps going out of site. They will climb to 260 pretty quick and then i just slow down. Timing is at 35 degrees with 93 octane gas.

[Infomaniac]

What oil pan does it have?

[don johnson]

Assuming all is good in the lower end a few things come to mind;
1. I assume it is not blown. Typical well prepared engines create oil heat in only two ways. Camshaft and pistons. Since your deal is Nat. Aspirated piston temp should not be an issue in driving up oil temps. That leaves camshaft. Is the cam new, if so maybe it is going flat?
2. What oil pan did you put on and what is the capacity. If you are overfilling the pan that can potentially create major heat issues due to windage and the crank whipping the oil. Are you seeing any fluctuations in oil pressure while running hard. If so that is a sign of oil areation caused by excess windage from oil levels too high...
3. Lastly could be caused by severe piston scuff. If the boring/ honing were done inaccurately (either tight or loose) that can cause the pistons to load wrong and could potentially build oil temps
4. Lastly, I am not familiar with the Vortec head but I remember reading somewhere that they are a lean, quick burn design characteristic. Since you fattened up the motor that theoretically should have dispelled a lean condition heating up the top of the pistons
Maybe someone else has greater knowledge of these heads and characteristics?

[badbug]

Oil is right on the full mark with the assumed right dip stick that was in the pan when i got it. Oil pressure is constant and never fluctuates.. Runs around 75-80 cold and around 60 psi hot revved up. Idles around 45-50 lbs. hot. Bore and hone job was done by professional and has done quite a few for me in the past with no problems. Clearance on pistons were set on the loose end since it was for a boat. I built this engine to try and see what is going on with the vortec cylinder heads at 5000 rpm and up. They dont like to go there without sounding like you have a screwed up ignition system. Last year i tried them and gave up on tuning them cause i just couldnt get them to run over 5000 rpm without banging out. The plugs look super lean so I kept richening it up and everythime i got richer, the thing would break up sooner in the rpm band. Now i am going to try and lean it out some more to see if it will clear up. There is something going on in the combustion chamber which is above my head. Last year when i replace this vortec head with a set of 781 heads, all problems went away and rpm's went on up to 5700 without any further problems all year. Pan is off a 7.4 330 hp mercruiser. Plugs look super lean when checked everytime. Cant get them to color at all