SouthTexan
Senior Member
- Joined
- Jan 24, 2015
- Posts
- 2,149
- Reaction score
- 1,303
- Ram Year
- 2014
- Engine
- 408 CTD
SouthTexan, how many times have I linked this and you never read it Ram reengineered the block and heads for the HD motor, including the coolant jackets in both. Now maybe your right and it's still heating up, but it's not the same block the cars use(except the Hellcat). Plus to my knowledge most focus in modern day has been more around monitoring cylinder head temps. Maybe Ram/FCA doesn't. Would also be very curious to see how oil temps figure into the equations.
IMO, the motor is very sensitive to octane as you suggested. I could even feel a difference in how the truck ran between 87 and 89 in come cases. When towing I always bumped up the octane regardless.
Sorry, I didn't fully read that the last time you posted it since the post was meant for someone else. From what I gathered from that article it seems that the blocks are the same for the most part besides "improved coolant jackets". That type of stuff was marketing speech for "a few more holes machined into it" back when I used to work for the manufacturers. Not saying that is the case here.
I knew the heads were not the same. There is no way they could be or you guys would be popping heads left and right due to the heat of a trucks duty cycle.
I think they should have done like Ford did with the 6.2L by starting from scratch making a new engine made for an HD truck instead of just making a 6.4L fit into the block dimensions that was originally for a 5.7L and modifying the coolant jackets. That is a lot to cram into such a space. Larger block dimensions would mean larger coolant jackets which means that the limp mode would probably be non existent. Not only that, but I would wager that the power output would have been considerably higher. I think the 6.4L is held back power wise and that it is mainly due to heat management and detonation. If the block was larger and could easily manage the heat in a truck application, I have no doubts it would be in the 440-460 hp range.
I also think they should have mated a better geared transmission specifically geared for a gas engine instead just putting a downgraded transmissions geared for a diesel with it.
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