Hemi vs Hurricrane

[ramffml]

Power on paper* and power to the road are often very different. While I agree in principle, I'd have to drive your 2-cylinder juggernaut before I believed it.

*most often the only thing published is peak power at RPM. This alone is almost meaningless. I wish someone could come up with a "power under the curve" formula that would give a more meaningful number. I became aware of this phenomenon the first time I had the opportunity to drive a Ferrari. I stalled the thing umpteen times because it was more gutless than a 6-year-old girl* at what seemed to me to be normal take-off RPMs. And it was. Because the torque curve was more like the HP curve of a "normal" American Iron engine. Fact is, the engine was founded on a race situation, where you are always within 1000 RPM or so of max HP. Not the way normal people drive on the street.

I realize this kind of representative number would be complicated by the power band, min/max RPM etc, but I can imagine a rating that would have 2 parts - power band width as a percentage of max RPM and power under the curve. Probably a lot more complicated that it seems at face value or someone a lot smarter than me would have already come up with it but it's one thing I constantly think of when I see max power/HP readings.

Oh, but give me a V8 any day. Or a V12 if I can afford it (not yet). Call me shallow but sound means a lot to me. The only 6 that sounds good is a Flat six, like the one in my Porsche. But that's the totally wrong configuration for a front engine truck. Maybe it could fit under the bed, hmmmm...

Exactly. This idea of using a single number for performance doesn't work, and it reminds me of my days when I built servers (powerful computers). Guys on my team obsessed over CPU ghz numbers, higher = better right? Well no, the bottle neck of a computer for many tasks is actually waiting for data to come off the drive. The difference in speed between a CPU and a disk drive is like 1000's of years of CPU idling, waiting for data to come from the disk. Instead of waiting for 1000 years it waits for 999 years with a slightly faster chip. Pointless optimization.

20 years ago I started experimenting with RAID arrays and later software solutions like ZFS striping and man what a difference in performance. The idea there is to split the storage into 2 or more pieces, and then chunck it out; half of the data is saved on one drive, while half is being saved on the other at the same time, and then it takes 50% of the time to save the data. SSDs helped huge on the desktop side of things to speed up computers. I'll take a slow chip and an SSD over a fast chip and magnetic drive, believe it or not they still ship those archaic things.

Anyway, side rant. My bad. Just reminded me that performance can't be reduced to a single number like cpu clock speed, or peak hp/tq, or GCWR while towing, or another one like total watts in a home theatre. It's all meaningless numbers taken just by themselves.

 

[Docwagon1776]

Which is why I wish there were a better number to refer to than max HP or torque.

Rolling start acceleration tests are about your best approximation, at least as far as usable power under the curve post torque management, etc.

Rolling start takes a lot of the traction limits out of the test, typically, though there's definitely cars that will break the tires loose at ridiculous speed on demand.

 

[Fatbob Frank]

That's because most of our driving is torque dependent. Stop light to stop light is all torque. You can run high gears on a high torque engine and get tons of speed. Like the old big block V8's that had like 350 HP but 500 ft/lbs. Tire roasters.

Really, horsepower is just a calculation based on torque and acceleration over time.

Give me all the torque, and give it to me at lower RPM's where I spend 99% of my time driving.

There's an old saying" America buys horsepower, but lives on torque"
This has been true for decades. And while HP #s continue to climb most people never capitalize those increases...Increased torque on the other hand you notice...

 

[DanAR]

Very true. I had the misfortune of buying a new 85 Corvette which had a miserable 230 HP. But that tuned port induction system made a ton of torque and it did a pretty good job of shoving you into the seat back from a zero or low speed. I think some of them with an optional rear gear set could run low to mid 14 quarters which was pretty good back in those days.

 

[mikeru]

There's an old saying" America buys horsepower, but lives on torque"
This has been true for decades. And while HP #s continue to climb most people never capitalize those increases...Increased torque on the other hand you notice...

That's one I haven't heard before. The saying I'm more familiar with is "Horsepower sells cars, torque wins races".

 

[knightjp]

Despite the fact that I've faced the dreaded lifter tick 3 times, I'm still a huge fan of the 3rd Gen Hemi V8. I love the sound. No 6 cylinder will beat the sound of a V8.
There are two engines that I consider as the best sounding of the 6 cylinders.
1. Alfa Romeo's Busso V6 (Alfa GT V6 / Alfa GTV)
2. Cologne V6 in a TVR S2

I'm glad though that Chrysler went in for the inline 6 rather than the V6. I6 engines from what I've read and heard will be better balanced and produce more torque. It will run better. I do wonder why they didn't revive their other famous name "Slant 6". Surely that will resonate more better with Mopar people.

 

[HEMIMANN]

Yeah, I6's are silent, I think that's what the V8 old crowd objects to. I like I6's too, ran a Cummins previously.

Gen III Hemi really should not have been a Hemi in this day and age. As I've said before, it should have been a modern 4 valve engine without all the funky Hemi geometry that only kicks in @ 5,000+ rpm for race cars. It was nothing but a stupid marketing campaign that worked at the expense of cam wipeouts.

GM & Ford have seen the light while Stellantis goes full Beemer w*h*i*z motor in a truck. wtf.

 

[Riccochet]

Yeah, I6's are silent, I think that's what the V8 old crowd objects to. I like I6's too, ran a Cummins previously.

Gen III Hemi really should not have been a Hemi in this day and age. As I've said before, it should have been a modern 4 valve engine without all the funky Hemi geometry that only kicks in @ 5,000+ rpm for race cars. It was nothing but a stupid marketing campaign that worked at the expense of cam wipeouts.

GM & Ford have seen the light while Stellantis goes full Beemer w*h*i*z motor in a truck. wtf.

If they didn't add MDS it would have been a lot more reliable. They had to lengthen the block further separating the crank from the cam, stuck an oil passage between the two and shallowed the lifter angle. MDS wasn't the cause of the failures, just a byproduct of it existing due to the design.

I think the Hemi was/is a great engine for the Charger/Challenger. Peak power in upper RPM's where those cars are intended to be driven. Two valve top/bottom head design is perfect for that, nothing really beats it. There's a reason every top fuel car runs 500 CI Hemi's, they're the best for what they do. Getting air in and out as quickly and efficiently as possible.

 

[knightjp]

I can't say for certain, but I did notice something. At the time the 3rd Gen Hemi was announced or released, Chrysler was just taken over by Daimler Benz. That was when they started using old E-Class Chassis for the 300 and Charger platforms.. I'm guess that Benz had access to all the Chrysler patents and decided to revive the brand by bring out a name that every Mopar lover would recognize - HEMI.
I also noticed that at the same time, AMG V8s suddenly got some serious grunt and Muscle-car style sound. Perhaps they too benefited from the Hemi head design in some way, incorporating it to their own engines. AMG engine have sounded that way ever since.
A couple of years ago, I had the pleasure of test driving a Jeep with the 4.7 Powertech. I'm not sure about the problem history with those engines, but for a vehicle that was over 10 years old, that engine was so smooth and so refined, I couldn't tell it was on or not. Power delivery was so linear and combined with the transmission, it felt like an electric car. This was Jeep Commander. I never forgot that test drive, even today.

GM and Ford are still selling trucks with V8s. I don't see why Stellantis can't do that now. I think if they offered the V8, no one would buy a Hurricane. So they will force customers to get the Hurricane by elliminating the choice.
Some youtube videos suggested that Chrysler has hinted that an all new Hemi is in the works, but those are just rumors and even if its true, I think they will wait to see who is the winner of the "Battery vs Hydrogen" war for the defacto fuel of the future and then put the money, R&D, etc., into it. Otherwise they might just kill it like they did with the Chrysler Turbine.

 

[ramffml]

If they didn't add MDS it would have been a lot more reliable. They had to lengthen the block further separating the crank from the cam, stuck an oil passage between the two and shallowed the lifter angle. MDS wasn't the cause of the failures, just a byproduct of it existing due to the design.

I think the Hemi was/is a great engine for the Charger/Challenger. Peak power in upper RPM's where those cars are intended to be driven. Two valve top/bottom head design is perfect for that, nothing really beats it. There's a reason every top fuel car runs 500 CI Hemi's, they're the best for what they do. Getting air in and out as quickly and efficiently as possible.

The hemi had MDS right from the beginning (2005ish). The block change in 2009 was due to VVT, not MDS.

I'm not at all dissatisfied with the "car engine" in my truck, I think if you drive and compare it to the GM v8s it feels completely normal even at low RPMS and slots in between the 5.3 and 6.2 like we'd expect given the HP ratings. It doesn't feel like a high revving screamer to me, and honestly I feel it almost tapers off above 4500 anyway. Maybe it's just me or maybe I don't spend enough time at those rpms. Of course one could argue that GM's v8s aren't exactly "truck engines" either, not like the Ford 7.3 is.

 

[KYPOTLICKER]

Good original question, thread took a mind of its own IMO. I previously owned an F 150 with the 2.7 Eco boost, had someone offer me what I paid for it 4 years, couldn't afford not to sell it. Very dependable power plant for me. I put right at 75k miles on it. originally missed the sound of a v8, but got over it pretty quick. Love the sound of the Hemi, but wouldn't let sound sway me personally one way or the other. Bough the ram for the interior and overall appearance TBO.

 

[HEMIMANN]

The hemi had MDS right from the beginning (2005ish). The block change in 2009 was due to VVT, not MDS.

I'm not at all dissatisfied with the "car engine" in my truck, I think if you drive and compare it to the GM v8s it feels completely normal even at low RPMS and slots in between the 5.3 and 6.2 like we'd expect given the HP ratings. It doesn't feel like a high revving screamer to me, and honestly I feel it almost tapers off above 4500 anyway. Maybe it's just me or maybe I don't spend enough time at those rpms. Of course one could argue that GM's v8s aren't exactly "truck engines" either, not like the Ford 7.3 is.

GM 6.6L?

 

[ramffml]

GM 6.6L?

Think its been a while since driving it, I don't know too much about it either other than the specs and that it is pretty competitive in the real world vs the Ford v8s. The Ford 6.8 and 7.3 are still simpler (they don't have GDI either). But now you have me curious, probably worth a little dive into that.

 

[ramffml]

GM 6.6L?

Do you ever drive around in tow mode with the pulsar while not towing? I swear it has a little bump in power vs stock right around 2000 and up, but hard at times to separate what I feel from the fact that the pedal is also more sensitive in that mode.

 

[HEMIMANN]

Think its been a while since driving it, I don't know too much about it either other than the specs and that it is pretty competitive in the real world vs the Ford v8s. The Ford 6.8 and 7.3 are still simpler (they don't have GDI either). But now you have me curious, probably worth a little dive into that.

6.6L is a new V8 for trucks only from GM. I don't remember much about it, yeah but it is GDI - but at least they didn't put their disastrous AFM cylinder cutout on it.

Ford supposedly had issues with lifters on the 7.3, and 6.8 is just a downsized 7.3. I like the fact they don't have GDI, and I guess the HD 10 sp is better than GM's. I worked Ford's truck configurator and found they only put 6.8 in the work trucks. Crap.

After 100 years, they can't get the complete recipe right, they don't value experienced engineers.

 

[HEMIMANN]

Do you ever drive around in tow mode with the pulsar while not towing? I swear it has a little bump in power vs stock right around 2000 and up, but hard at times to separate what I feel from the fact that the pedal is also more sensitive in that mode.

Oh hell no! It's jumpy as hell and goes like a banshee. It's both - the gain is higher and the fueling is higher.