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MOPARs from the late 60s and early 70s with 426 Hemi engines could turn the quarter in the low 13s at 107 mph. They, of course, were handicapped by skinny F60 Polyglas tires.

If a 1970 Hemi Challenger raced a 2016 Scat Pack and both had racing slicks, which one would win?
 

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I don't think a relatively stock 426 Hemi car would run mid/high 11's like my Scat Pack. I'd have to give the win to the new Scat Pack. I would think a relatively stock 426 Hemi with good tires and traction would likely run mid/high 12's in the right conditions. If you installed some headers, altered the ignition curve, and put some steep gears out back then it'd probably run low 12's. Would be a good race then.
 

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My 6.4L (in an SRT not a Scat Pack) is rated with more HP...and it might be faster....but it sure feels weaker than a 426.

The 6.4L of course also benefits from 50 years and billions of dollars worth of R&D in almost every area of engine design. EFI, exhaust tuning, combustion chamber design, roller cam, etc.

Plus the 6.4L is not putting its power through a less efficient trans with only 3 gears. I'd bet a 6.4L equipped with a 3 gear trans would be significantly slower.

I like the 6.4L just fine but it doesn't have the 'brute force' of a 426.
 

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The Scat Pack bone stock traps 112-114mph. The 426 trapped 107mph stock. I don't understand how that would feel weaker?

I agree on the transmission point, a big part of the Scat Pack's ability to get down the 1/4 mile so fast is due to that A8 transmission. The first gear is ridiculously steep, and the engine never gets below 4700-5000RPM the entire length of the track after that because of the additional gears. Not to mention how fast it shifts too. Much more efficient than an old 3 speed auto.
 

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The 426 was rated at 425 Gross h.p. ,which was meant the engine was tested with no air cleaner, accessories or exhaust system.

A late 60's 426 street Hemi had a actual net horsepower rating of around 350 h.p. once it was installed in the car.

Rear wheel horsepower was in the low 300's. Torque was only in the 350's or so.

In other words.... it was about as strong as a stock 5.7L.

Now a 1970 Challenger was a few hundred pounds lighter than our cars, but that wouldn't matter.

A stock Scat Pack would destroy a stock 426 Hemi car.....by a second in the 1/4 mile...at least.

Here is a good article to read:

https://www.hagerty.com/articles-videos/articles/2013/08/13/horsepower

The 426 was a great engine, however IMO... the modern 6.4L is the greatest N/A Chrysler engine of all time.
 

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Wouldn't even be close, sorry. These new cars are so much faster and engines are for sure more powerful.
 

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In the 426's defense, it was rated at 425hp at 5000RPM. I watched a show on the 426 one time and this guy built an exact part for part OEM 426 out of a stock block and parts. Stock specs on everything, might have been 1/4 point higher compression ratio, otherwise stock like it would have come from the factory. He got around 430 hp or so at 5000RPM on the dyno. But when he revved it higher to 6000-6200 he got 490hp! So I think they just rated them at 5000RPM to keep insurance companies from charging too much back then. The 426 actually made quite a bit of power for a late 60's/early 70's engine.

But stock for stock, I can't see a 426 taking out a modern day 392. If you could somehow hook up the 426 to the new A8 transmission like the other poster mentioned, that would certainly level things out quite a bit. Still not sure it would beat the 392, but it would at least be a more fair race.

But if you're just comparing cars from two different eras, it's no surprise the new ones with all the new advancements and technology would be ahead. Active intake runners, active exhaust, variable valve timing, fuel injection, computer controls, sensors, etc. When you look at what the old engines had to work with back then, it's pretty impressive they were putting out the horsepower numbers they were.
 

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In stock trim, the 426 was no match for the current 392. I have old magazines from those days, including one where they took a hemi Roadrunner, bolted on slicks, installed colder plugs, and recurved the distributor. The best they got out of it was 13.32 at 107.65 mph. The trap speed tells the story. For the most part, stock 426 cars were doing 13.5 at 105.

The old ones feel quicker due to the torque delivery. I felt the difference with my SP over the old big block cars. The Hellcat puts that perception to rest...no old muscle I've ever owned, driven, or ridden in pulled like the HC. Again---talking generally stock vs. stock.
 

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I want to point out that when I state a new A8 is more efficient than the old 727, I don't really mean shift speed but rather power consumption.

I wish the SAE or Chrysler would release dyno figure on these transmissions so we could really see how much HP they consume. I am very sure the A8 loses way less HP in any case. In the old days, the stick cars were often fastest because despite the manual shifting they consumed far less HP than the auto's. Not so any longer. The new auto's are not wasting nearly as much HP.

As I said, I like the 6.4L just fine but it's not the 'cat's ass' compared to a 426. I also find that most people who think the 6.4L is way better are people who are bench racing based on magazine results and never have actually driven a 426 powered car. I'd bet if you put a 6.4L into a Roadrunner with no other changes you'd find the 6.4L has a pretty soft low end power delivery and had a tough time with only three gears.

And let's not forget the many advantages of EFI - not only do you lose the sloppy Carter AFB's, you also get full mapping of spark advance. That's a serious thing.
 

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I want to point out that when I state a new A8 is more efficient than the old 727, I don't really mean shift speed but rather power consumption.

I wish the SAE or Chrysler would release dyno figure on these transmissions so we could really see how much HP they consume. I am very sure the A8 loses way less HP in any case. In the old days, the stick cars were often fastest because despite the manual shifting they consumed far less HP than the auto's. Not so any longer. The new auto's are not wasting nearly as much HP.

As I said, I like the 6.4L just fine but it's not the 'cat's ass' compared to a 426. I also find that most people who think the 6.4L is way better are people who are bench racing based on magazine results and never have actually driven a 426 powered car. I'd bet if you put a 6.4L into a Roadrunner with no other changes you'd find the 6.4L has a pretty soft low end power delivery and had a tough time with only three gears.

And let's not forget the many advantages of EFI - not only do you lose the sloppy Carter AFB's, you also get full mapping of spark advance. That's a serious thing.
 

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I want to point out that when I state a new A8 is more efficient than the old 727, I don't really mean shift speed but rather power consumption.

I wish the SAE or Chrysler would release dyno figure on these transmissions so we could really see how much HP they consume. I am very sure the A8 loses way less HP in any case. In the old days, the stick cars were often fastest because despite the manual shifting they consumed far less HP than the auto's. Not so any longer. The new auto's are not wasting nearly as much HP.

As I said, I like the 6.4L just fine but it's not the 'cat's ass' compared to a 426. I also find that most people who think the 6.4L is way better are people who are bench racing based on magazine results and never have actually driven a 426 powered car. I'd bet if you put a 6.4L into a Roadrunner with no other changes you'd find the 6.4L has a pretty soft low end power delivery and had a tough time with only three gears.

And let's not forget the many advantages of EFI - not only do you lose the sloppy Carter AFB's, you also get full mapping of spark advance. That's a serious thing.
Yeah, us younger guys can only go on research; however there is no dispute that net power was 350 h.p. in stock form. It has also been shown, several times, that RWHP was in the low 300's.

Engines are a lot like football teams. People love to talk about the great 60's / 70's football teams... both college and pro.

However, annihilation is the only word that fits if 2016 Alabama meets 1966 Alabama.

A bone stock 426 car would struggle to beat a stock 2015 5.7L A8 car. That is a fact and I bet the 2015 5.7L would win more times than not.

I've ridden in some stockish big block cars and they do feel strong.... however in reality... the Minivan in the next lane is probably laying down more power (and faster to boot).

That isn't a slam on nostalgia... but a credit to the new stuff.
 

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I was in and around 426 cars back then, as well as 454 Chevelles, all sorts of 440 Mopars, 455 Pontiacs, 428 Fords, and most of the other big blocks then. The 392 doesn't have the brute feel of the old iron, but it gets to the end of the quarter first.
 

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Could be gearing. If the older cars had an easier gear ratio they would seem lighter on their feet.

My 1970 Challenger had a built 318 but 3.91's in the back which made it very quick. But 3500 rpms on the freeway was not fun.
 

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The most recent episode of Graveyard Carz did a dyno on a '70 with the 440. Granted, it was tired, but rear wheel horse power was 205. That was rated at 375 gross, so there was a lot of power lost with air cleaner, power accessories, exhaust and that old 3 speed tranny. I had a '68 Charger with that same setup, and it was fast as hell for the '80s, but a damn Honda Civic would beat it today.
 

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The 426 Hemi's(the regular street Hemi anyway) closest counterpart to a modern Hemi would be the 6.1 with respect to how much power it makes and how the motor delivers it. And that's a good running 426, they were known to be finicky.

I've been in several old muscle cars and in my opinion the 6 speed manual 392 Challenger is so close to the soul of what the good ones were, the big boys of the day. Hits hard with torque and pulls well through the rpms. Super fun and brutish. I kind of miss mine sometimes. But I wouldn't trade back from my 8-speed auto Scat Pack ever. This thing is as fast as an old ZL-1 Camero or L88 corvette would have been. To anyone who doesn't think these newer cars feel the same I seriously have to question who the bench racer is and challenge you to get your modern Mopar on the drag strip! You telling me 1.7 and 1.8 60 foots don't feel quick?
 

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Test result from Car and Driver 1970 Dodge Challenger R/T 426ci/425hp, 3spd auto, 3.23, 0-60 - 5.8, 1/4 mile - 14. 10 @ 103.20mph.
Test result from Car Craft 1970 Dodge Challenger SE 426ci/425hp, 4spd manual, 4.10, 0-60 - 6.3, 1/4 mile - 13. 10 @ 107.12mph.

Test result from Car and Driver 2015 Dodge Challenger Scat Pack 392ci/485hp, 8spd auto, 0-60 - 4.2, 1/4 mile - 12.6 @ 114 mph.
Test result from Car and Driver 2015 Dodge Challenger Scat Pack 392ci/485hp, 6spd manual, 0-60 - 4.4, 1/4 mile - 12.9 @ 113 mph
 

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I pulled a 1.61 60ft time with my Scat Pack just a few weeks ago and ran a 11.62 at 117mph on that pass. It also did 0-60 in 3.3 seconds that run. That did not feel like "soft" power delivery on the launch at all haha! That was with just basic bolt ons and a tune.

I have never ridden in an old 426 Hemi car, but I know they are fast. The guys in the Pure Stock drags are running high 11's to low 12's with them and they're only allowed to do minor mods to those cars. They are capable of great times with some tuning/adjustments. But the fact is the new ones are faster.

That said, I understand where people are coming from regarding the "brute force" comments. I have an old 1972 Chevy Nova that has a 383 stroker in it (425hp or so). That car runs 12.30's at 110mph with 1.70 60ft times. That car actually feels like it's faster at times because of how the car is set up, the suspension, the engine noise, exhaust note, etc. Going 110mph in that car is way scarier than going 117mph in the Scat Pack! The old cars just have a different feel to them that you can't really quantify into numbers.

The old transmissions definitely sucked up a lot more power. I think most transmission shop calculators figure about 20% loss through the drivetrain with a TH350 trans and even more with a TH400 trans. The A8 uses significantly less. The 392 is rated at 485hp yet many guys are putting down 430hp at the wheels. That translates to 12% loss if that. Of course the 392 could be slightly underrated as well, but even so, I can't see it being much more than 15% loss at the most. Much more efficient than the old transmissions.

The old Carter carbs always get a bad rep, but they're actually pretty good and easy to work on carbs. Back then though in the early 1970's, most cars were running points, if not all of them. Points SUCK compared to HEI setups, and HEI SUCKS compared to modern day computer timing controls. For an all out drag setup, the best thing to do if you had enough cam duration and gearing, was to simply lock out your timing. I did that on my Nova and it has WAY more bottom end power now. I tried all different timing curves over several years and in the end locked out timing is the best setup for that car given the compression ratio, cam duration, loose converter, and gearing. Most of the cars coming out of the factory back then had lame timing curves, like 2-4 degrees retarded from peak power in total timing and then all in timing not hitting until 3500-4000RPM. This was to prevent engine damage from bad gas, morons that ran crappy gas in their cars (like today, except no computer controls to pull timing from knock/detonation), and reduce warranty issues. Years ago you could take your distributor out, take it a tuning shop, get a performance curve done, and pick up tons of power from that alone. These modern cars can do all that crap on the fly in various conditions/times whenever the computer sees fit. Best of both worlds there.

At the end of the day, you really can't compare the two engines. They are from two completely different times. If anything, you are merely comparing the benefits/advantages of technology advancements over the years compared to how things were ages ago. For the time, say in 1970 or so, the 426 Hemi was a total beast of an engine, a modern marvel, it was the king. But that was nearly 50 years ago. Things have changed a lot since then. It doesn't mean the old cars suck, in fact in many cases they are cooler than the new ones. But the fact is from point A to point B the new cars are 95% of the time going to get there first due to all these advancements over the last 40-50 years. It would be sad if they couldn't honestly haha!
 
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