Are there any options for high capacity oil pans for the M8? I’m not seeing one for the Milwaukee 8 motors on Harley’s web site. I would really like to add more capacity for my 124 build. Might also like to add an oil filter relocation kit and oil cooler fan to help keep everything cooler.

 

More oil does not increase cooling capacity. It only takes longer to heat up.

 

The M8 already takes over a quart more than the Twin Cam engines. Cylinder head fans or a good fan assisted oil cooler will help more than more oil which as noted will just take a little longer to get to temp.

 

I appreciate the replies, but as I noted in my original post I’m exploring three potential avenues to potentially aid in cooling the bigger engine:

1. High capacity oil pan - I’ve posed the question asking if anyone knows if there is one because I haven’t seen one for the M8s. I know Harley offered one for the Twin Cam motors specifically for high performance motors.
2. Oil cooler fan - I will most likely get the ThunderMax oil cooler fan since that is the tuner I’ll be using and it is plug and play, but I know there are several options there.
3. Oil filter relocation - I’m considering the DKCustoms relocation kit for this. It increases capacity a little, gets the oil filter away from the motor out in the wind, and as a bonus makes oil changes easier.

I’m not sure I can agree with the two replies asserting that more capacity doesn’t help reduce heat though. The M8 has higher capacity than the TCs because they are oil cooled and lubricated. Additional capacity by definition absolutely means that it takes longer to heat up, but also provides more time to cool cycling through the cooler and oil pan before going back through the engine. If a higher capacity oil pan was available, theoretically it would:

• Provide more time for the oil to cool before going back through the motor.
• Provide the ability to dissipate heat better as there is more of it.
• Reduce oil breakdown between oil changes.

The description from Harley for the high capacity oil pan for the Twin Cams specifically describes this:
”A great addition to a high-performance motor, or for the rider that tours in extreme temperature conditions, the Screamin' Eagle® cast-aluminum oil pan is designed to increase the oil capacity by 1.5 quarts over the Original Equipment pan. Increased capacity means the oil cycles through the engine less frequently and the oil can remain in the pan for a longer period of time.”

Think about it this way...

If you boil a pot of water all of the water is exposed to heat at the same time, so naturally the greater the water capacity the longer it will take to boil, and if all the water remains in the pot exposed to continuous heat it will all stay at a boiling temperature. (As asserted by the two replies.)

If as you are trying to bring your pot of water to a boil but keep taking some of it out to cycle it through a cooler then re-add it to the pot and continue the process of cycling water out to cool then it will certainly take longer to get to a boiling temperature and will potentially disrupt the boiling process altogether.

If in addition to cycling water out to cool you increase the amount of water, the likelihood of reducing the temperatures is theoretically also increased.

Perhaps I’m wrong though, so when I get a moment I’ll try to research the science. In the meantime, if anyone is aware of a higher capacity oil pan for the M8 motors I would be interested in knowing about it.

If the concept has born out that additional capacity cycling through the motor didn’t help to dissipate heat and they aren’t making them then I guess I won’t get one ;o)

 

I understand the logic behind your thinking, As far as cooling ability for dollars spent a high quality oil cooler gives the best return for your investment. Not all coolers are created equally, there was a good article on oil coolers a few years back in American Iron, the better coolers have "turbulators" which move the oil around in the tubes. If I remember right Jagg and Harley were the only ones made like that at the time.I actually run one of each on my twin cam softail. DK Customs has quite a bit of data about cooling on their website and I believe it to be pretty good information. As far as an extra capacity oil pan on an M8 I think would be a good idea if it had better cooling fins, I'm not very fond of the idea of adding more oil to this motor, I run my 17 CVO street glide a quart low, but with a bigger pan I would run the recommended amount for the stock pan and it would give this motor a little more breathing room, which I think would go a lot farther helping this motor than another quart or more of oil would