Old Hemi vs new Hemi

[David]

Car and Driver tested the Chrysler 300 SRT8
425 HP
13.4 quarter mile
172 top end

What 426 Hemi could run with both ends of that? I think none.
So today's 425 HP must be more powerful than 60's 425 HP.

[10.5' Tunnel]

Maybe not. Think of a 60's car suspension, weight. I think the whole hemi thing is more of a marketing thing, but whatever :cool:

[CDave]

I believe the standard they use today is with all accessories on the engine. The alt., PS pump, A/C compressor, etc. Back in the 60's they didn't have all that on the engine when it was dynoed.

It's something like that. They use a different rateing system today.

[whatsamerc??]

i think tires were the biggest problem back the. traction was hard to come by with 14 inch tires. i wasnt born in time to get to run an old hemi but i enjoy
letting mynew hemi ram stretch its legs. 108 sucks though ...benji

[Euroski]

Computers make engines run very well! Back in the mid to late 90's Porsche had a 3.6l twin turbo 6cylinder with around 430hp+++.

[Dave S]

When the 426 came out the racers moved up from the 392s......I wanna see the new hemi in a rail beat the old 426. ;) I wanna see a 426 with new stuff on it...I want too much. :D

[heath brinkley]

60's 425 HP was gross hp. Today's 425 HP is net HP. pulleys,belts, pumps,exhaust, everything it would come with on the car.

two equally prepped hemi's would be a nolo contendre. 426 all the way.

[David]

I think that a Chrysler 300 SRT8 with 411 gears and slicks would smoke a Hemi Charger with 411 gears and slicks in the quarter. Everything stock except rear end and tires.

172 mph with a big brick takes real HP. Gear it to go 110 mph like a typical Hemi Charger and see who's faster in the quarter.

The SRT8 went 13.2 @ 109 in the quarter. Speed at the end of the quarter is a better indication of HP than elapsed time. How many showroom stock cars back in the day went 109?

SAE net HP came out in 1972. Engines have been rated ever since with all accessories. But there was a lot of optimism in 60's HP ratings that went beyond running the engines on a dyno w/o accessories. Sort of like PWC speedometers.

I have had a lot of people tell me that the 426 Hemi was rated conservatively. The book I bought about the engine quotes the engineers as saying they ran 425 on the dyno. Maybe, with the airbox removed, headers, and no accessories.

I would expect the 426 to have more torque.

Hemi's work. Its not marketing. They don't work as well as 4 valves but they are cheaper, smaller, and lighter than DOHC 4 valve heads.

No doubt for car engines these are the best of times.

I am optimistic about DI 2 strokes.

[heath brinkley]

no doubt a new 300 would outperform an old charger. I said two equally prepared motors. NO WAY a 350 inch Hemi would run anywhere near a 426 Hemi. HP per cubic inch. Physics. Indeed we're living in a good time for car motors, but you can apply all those same advantages of today's motors to an older 426 and you come out ahead, period. ;)

If not Chrysler wouldn't be selling crate 426's and Chevy wouldn't be selling crate 502's.

[Ted Stryker]

I don't know any particulars about the heads, but todays hemispherical heads could be just plain better... Making better use of the 350 c.i. is the reason you don't need 426 inches... My Father and I used to have this discussion regularly... My dad is a GM saleman and he couldn't invision that the cars of today could make real, raw HP like back then... He stood with the opinion that the performance comparability was due to just traction and car weight... Cars nowadays are just as heavy, and even with equal traction the new cars will simply power around the old carb engines... He recently took a ride in Doctors 6-speed 02' Vette that had a 382 with some head and cam work and 3.73 gears making a bit over 500 to the wheels and 20 mpg... He see's now that the newer cars don't have giant engines because they don't need'em...

[Ted Stryker]

What is correct with trying to compare old vs new by saying " put the new stuff on the old big motors"...? If you were to do that then what are you comparing... They have to butt heads as they were built, not by shifting technolgy over to the old... If you were to do that, you would just be comparing cubic inches... What is being compared to begin with is technology... What else is there in an engine, other than cubic inches...It takes no R&D or technology to make a bigger bore and stroke...

[baja200merk]

Care and Driver tested the Chrysler 300 SRT8
425 HP
13.4 quarter mile
172 top end

What 426 Hemi could run with both ends of that? I think none.
So today's 425 HP must be more powerful than 60's 425 HP.

its got a hell of alot to do with the fact that the car its in is light, the trannys have improved alot with faster shifts and wut not, the suspention is a "state of the art" and the tire technology is way advanced too... :)

this will prove it...
i think it was on the speed channel where they took a honda oddesy (mini van) totally stock agianst a dodge hemi charger or challenger (not sure wich) and they raced them through a coned coarse... the minivan beat the charger because of the traction and suspention :eek:

my .02 im no pro hehe
kevin

[Ted Stryker]

I also saw a heads up between an M-5 or M-3 ( can't remember ) versus a 66' big block vette, both showroom stock in the 1/4 mile... Guess who won...

[heath brinkley]

Care and Driver tested the Chrysler 300 So today's 425 HP must be more powerful than 60's 425 HP.

Back to the original question, Yes, Today's 425 HP is more powerful than yesteryears 425 HP. Because Gross and Net readings.

Comparing a 60's stock hemi to a stock hemi of today the new one beats it.

But to say which is the better motor, depends on how you mean better. Better as in, as is, the new one. Better as in which would you take if offered both, 426.

[David]

I originally posted due to shock and awe at the 170+ top end.

The 300 C SRT8 weighs 4212 lb. Almost as much as my Lotus and Miata combined. On the plus side, it has a lot more HP and interior space than both my cars combined.

I also posted because I've heard lots of people claim that the 426 was under rated at 425 HP. If it was, its not by enough to offset the difference between SAE gross and SAE net.

Which engine would be more cool to put on a stand in my garage and stare at? Sure, the 426.

The American's are masters of obsolete technology when they put their minds to it. Just look at the Corvette small blocks and the DCX Hemi. But it is obsolete technology and I'd rather have a 240 HP 2L Honda S2000 engine on that mythical stand in my garage than a new Hemi.

Or are the American's smarter than I know? What's the cost to build of a titanium rod 2L 4 vs a pushrod 8?

There are a lot of ways of looking at the world. For example, one could argue that every 4 valve engine is a Hemi.

My Lotus engine's combusion chamber sure looks like a scaled down 426. Incredibly, the included valve angle and bore/stroke ratios are the same. But Lotus put twin cams, short tuned intake runners, tubular headers, and two 2 barrel carbs on that little 4. Lots better stuff than Chrysler put on the stock 426 Hemis.

Even the Lotus accessories are under geared so it overheats and the headlights dim at idle. Less power loss that way.