New I-6 info...

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DanAR

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My brother, my wife and I took my Mom’s leaning tower of power 6 Plymouth Scamp to the top of Pikes Peak many years ago. As we were approaching the last crest before the visitor center parking lot we were down to about 1- 2 mph with the pedal floored, blowing black exhaust and backing up a line of traffic. My brother finally crawled out the window while creeping along and pushed us to get us the last few feet over the crest and coast down to park. After a visit and cool down we were on our way back none the worse.
 

Wild one

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That was my intention to my statement, that the 6.4 is not competitive to the competitions current offerings. Not that it isn't capable, I own one, I know it's capable. Outdated fits when compared to the GM 6.6 and Ford 6.8 and 7.3. Just as the 6.0 was outdated in the GM, and the 6.2 in the Ford. Which is why they updated them.

Personally, I wouldn't mind them keeping the 6.4, just update the tune and give it some more beans over the next couple years until they come out with something else. I'd love to see a 7.0 426 for the HD trucks. A man can dream! :cool:
To keep a decent rod/stroke ratio ,so the engine will last a 100,000 miles would take a taller block,or shove the wrist pin up to the top of the piston,which creates it's own issues,with piston rock and ring flutter.
 

Riccochet

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To keep a decent rod/stroke ratio ,so the engine will last a 100,000 miles would take a taller block,or shove the wrist pin up to the top of the piston,which creates it's own issues,with piston rock and ring flutter.
There's a ton of 360LA's bored and stroked to 428 ci that run forever.

I'd expect them to make a new block, get rid of shallow lifters, drop the cam an inch or two, bigger bore. No way I'd expect them to reuse the 6.4BGE block for a 426 build. That's just stupid.
 

Wild one

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There's a ton of 360LA's bored and stroked to 428 ci that run forever.

I'd expect them to make a new block, get rid of shallow lifters, drop the cam an inch or two, bigger bore. No way I'd expect them to reuse the 6.4BGE block for a 426 build. That's just stupid.
You're dreaming if you think they're gonna come up with a new block to make a 426,lol. You're also dreaming if you think a 428 cubed LA will make a 100,000+ miles with-out a rebuild,if it does,it's the oddball in the crowd,not the majority,lol. If you understand rod/stroke ratio's,you'll know why a 428 cubed LA block won't last ,the rod is always putting stress on the outer cylinder wall,by forcing the piston into the loaded side of the cylinder wall,and consequently shortening the piston and cylinders life expectancy.
One of the reasons why old school small cube engines like 318's/302's/283's had a good rep for living and taking a pile of abuse,is because they had a good rod/stroke ratio.Short stroke/long rod engines are generally longer lifed then a long stroke/ short rod combo.
 
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HEMIMANN

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The biggest advantage to the truck 6.4 is it's ability to work at full load for 12 minutes on 87 octane,i don't think Fords Godzilla has that same ability.If it does,i've never seen it posted anywhere

Yeah, but remember the hoo-hah over the ignition timing strategy, and the validation readout vs. octane gas used? Can't recall who provided the data, but distinctly remember the default ignition timing is advanced for 89 octane gasoline.

If using 87 octane, the knock sensors let it knock then pull back the timing, then repeat the short term testing for octane for uknown cycles. Then goes into long term checking for octane by allowing knocking every so often by advancing timing.

Well, that don't make it for me - knocking an engine repeatedly to set the timing back. So's I use 89 octane all the time. Slightly less fuel consumption and higher torque makes up for some of the extra gas price anyway.
 

Wild one

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Yeah, but remember the hoo-hah over the ignition timing strategy, and the validation readout vs. octane gas used? Can't recall who provided the data, but distinctly remember the default ignition timing is advanced for 89 octane gasoline.

If using 87 octane, the knock sensors let it knock then pull back the timing, then repeat the short term testing for octane for uknown cycles. Then goes into long term checking for octane by allowing knocking every so often by advancing timing.

Well, that don't make it for me - knocking an engine repeatedly to set the timing back. So's I use 89 octane all the time. Slightly less fuel consumption and higher torque makes up for some of the extra gas price anyway.
As far as late model engines go,the 6.4 is a low compression engine.
If you haven't read this article,it's worth spending a few minutes reading it.

 

HEMIMANN

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As far as late model engines go,the 6.4 is a low compression engine.
If you haven't read this article,it's worth spending a few minutes reading it.


Does it matter what the compression ratio alone is? The ignition map is developed to match fueling that goes with the low compression cylinder filling - you can make any engine pre-ignite if you advance the spark enough.

So the point is, if your spark advance curve is set for 89 octane gasoline for any particular engine, that's what it should be. Did you see the data maps provided by the member who watched his timing?
 

Wild one

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Does it matter what the compression ratio alone is? The ignition map is developed to match fueling that goes with the low compression cylinder filling - you can make any engine pre-ignite if you advance the spark enough.

So the point is, if your spark advance curve is set for 89 octane gasoline for any particular engine, that's what it should be. Did you see the data maps provided by the member who watched his timing?
Most engines have an ideal timing curve,and advancing past that curve even with higher octane fuel doesn't add squat for power.Engine Masters did a test of this,and they found the ideal timing curve on 87 octane,was pretty well the same ideal timing curve for 91 octane.The hemi might be geared for 89 octane,but the power loss by using 87 octane in a truck 6.4 probably isn't as much as you think. I bet if you had the truck on a dyno and tested rwhp it wouldn't be as big a loss as you think,and i'm not sure the knock sensors would pull as much timing as you think,unless you were at or below sealevel on a 100+ day,and under those circumstances the knock sensors would be pulling timing on 89 to
 
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