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old skool 450HP? vs new HP?

Discussion in 'The Hokey Ass Message Board' started by Jason455, Dec 29, 2012.

  1. Jason455
    Joined: Jun 21, 2004
    Posts: 515


    I have a 1970 454, 280 comp cam with ported 69 425hp 427 heads. Runs out REAL STRONG in my hotrod. Im figuring approx. 450hp. Friends stop over with their new trucks toating 25mpg and near 400 horse stock. Ive rode in these trucks and Im thinking the new HP is rated on little 1-3" tall horses where the old motors are rated at full size horses(7-8 foot tall)? Maybee Ive had too many Barley pops but the new stuff seems lacking. I realize trucks are heavy but I remember old trucks with Big blocks(chevy ford mopar etc.) Is it just me? bench racing? Im 40 now so we never lined them up, but seat of the pants tells me old school is much more satisfyting.
  2. Deuce Roadster
    Joined: Sep 8, 2002
    Posts: 9,519

    Deuce Roadster
    Member Emeritus

    Compare the TORQUE :eek:

    Not the HP rating. Also ... the engines can be rated at entirely different RPM levels. A big Block makes torque ... where small blocks as a general rule has less torque.

  3. k9racer
    Joined: Jan 20, 2003
    Posts: 3,091


    deuce roadster is correct. A lot of engine shops use a standard day formula to evaluate HP because of air denisty and temp. this always tips the scale in their favor.. Torque tells the truth. The dyno I use is a Stucksa and its over 44 years old all manual readings.
    Last edited: Dec 29, 2012
  4. pdq67
    Joined: Feb 12, 2007
    Posts: 787


    LS engine vs 1st Gen. SBC and it's their heads that make the new power! (And Bill M. still sells a 1st Gen SBC block that will mount the LS heads so go figure!!).......

    And take a 230hp/454 mid '70's p/u engine and add a 4.25" crank to make a .060"overbore 496 or so engine with like 9.5 to 1 CR and you are looking at 500 hp and more T with only a small hy-cam and decent carb and intake along with a pair of 1.75" headers.

    I'm talking "tow-truck" motor here..

    My 496 has a good old CC 282S solid cam in it along with about 9.75 to 1 CR and Merlin 2.19"/1.88" heads and a 750 Holley on a single plane oval port Strip Dom. with the 1.75" Heddman headers that per D2K should make like 550hp/580T at 5500 rpm.

    I will be tickled pink for 90 percent of that.

    I also have a UDHarold solid lifter copy of CC's great old 288AR that he designed for me that I can install and probably gain more hp EASY!!


  5. stude_trucks
    Joined: Sep 13, 2007
    Posts: 4,755


    Age old story. Best not to even worry about it. No matter what you have under the hood, somebody's always going to have something better.
  6. 57Custom300
    Joined: Aug 21, 2009
    Posts: 1,363

    from Arizona

    Agreed. The old "mines bigger than yours".
  7. ken1939
    Joined: Jul 5, 2008
    Posts: 1,558


    Followed by the pissing contest :)
  8. The old HP rating system was a joke, and everyone knows it. The musclecar engines were rated at just UNDER 1hp per cubic inch to make the cars cheaper to insure.

    Years ago, Dick Landy built a "blueprinted" 426 Hemi for a restoration. Everything was exactly the way the factory did it in 67 or whatever year the engine was. They dynoed it, and it made 580hp, not the advertised 425... Even made OVER 425 with one plug wire off!

    Today's engines feel weaker at the same ratings because the OEMs have been forced to (GASP!) be honest about the power output.

    Having said that, the OPs comment about vehicle weight is true. Put that new 400hp mill in your "hotrod", and then see how you like it...
  9. mcmopar
    Joined: Nov 12, 2012
    Posts: 1,650

    from Strum, wi

    When you add in all of the electronics that limit power so you don't spin the tires, the hp rating feels different also.
  10. Arguments about HP are as old as cars themselves. Dynos can be made to say what you want (to a point) then in the end what trans. and/or rear end do you have (final ratio) ? Weight? So many factors but everyone seems to ask the same question "how much HP does it have?" Pick a # and through it out, the proof is on the pavement.
  11. raprap
    Joined: Oct 8, 2009
    Posts: 768

    from Ohio

    The old age question Hp vs torque?
    If you are street racing, then definetly go with gobbs of torque. If drag racing, go with HP. The methods of going fast have not changed since the beginning. How much you want to pay and how quick you want to go are the qualifying measures here.

    Example- In the mid 60's, everyone wanted a stoplight racer that could prove it's worth on the street and then on the strip. Not really possible but a few people I knew pulled it off. One had a 50 Olds fastback with a straignt 8, Hydro and 5 strombergs. almost impossible to beaton the street and strip. The other had a light 66 Nova, 327 punched out to 355, 2-fours and 5:10 rear. Again nearly impposible to beat especially as he would pulled the front wheels off the ground in the first 2 gears!

    Torque, Hp and light weignt will do it every time. Great times!
  12. I know this won't be a popular comment, but the new stuff responds to bolt-ons way better than the old stuff because the design is much more efficient. Example: Take a 350 and a late model LS 5.3 and do similar mods (cam, exhaust, even remove the fuel injection on the 5.3 and go with a carb). The LS will make more power and torque because the heads are way better than the First Gen small blocks. On the other hand, the big block stuff from back in the day still reigns king over the factory big block stuff from today because today's engines are designed for heavy truck use, and not "muscle" applications.

    The drawback is, the LS engines are hideously ugly and aren't the ticket if you're trying to build a traditional car. If that isn't a requirement for your build, then an LS with the fuel injection and a 4l60E trans makes for a killer combo that gets great mileage, makes good power, and doesn't leak. There are guys out there buying $500 LM-7 iron block 5.3 truck engines and merely changing the cams and springs to the factory Vette LS6 parts and bolting on a 77mm turbo set-up and making 560 horsepower for less than $3200. Whether you like that or not, it's hard not to like 560 horsepower and 20 miles per gallon for that cheap. I like horsepower and mileage, and you just can't get those numbers from a First Gen small block.

    I've had many, many small and big blocks over the years and I love 'em. I haven't played with the LS stuff yet, but damn, it's so tempting........
  13. Joe H
    Joined: Feb 10, 2008
    Posts: 1,080

    Joe H

    Your guessing at your hp numbers, until its on a dyno its just a guess. New cars and trucks must put out what is advertised, they can't afford to be sued by everyone who dyno's one. Most of the older stock everyday engines would dyno out pretty close to advertised hp, it was the high performance engines that were derated for insurance reasons. They were all tested bare bones, in '73 they changed testing methods, and I suspect that has changed again. You just can not compare numbers. My uncles 1911 Stanley Steamer makes 500 + ft pounds of torque as soon as the throttle opens, but still only manages 30mph and barely keeps up with traffic.
    New cars won't feel the same due to weight, noise, and power curve, but its there. Your 40 year old car is noisy, and rough ( not bad mouthing you or your car ) , not super quite and tight like modern equipment. Sure yours feels faster, thats why we like them, its no different then riding in a four speed car or automatic, the four speed always feels faster. New cars are the same way, they apply the power differently. That doesn't mean they have less power.

    New trucks with 400 hp are pushing around 5000 to 6000 lbs, lose about ton and it will feel dam fast!

  14. tfeverfred
    Joined: Nov 11, 2006
    Posts: 15,792


    Are they talking "NET" or "GROSS" horsepower? That's a difference as well.

    Wikiposer says:

    SAE gross power

    Prior to the 1972 model year, American automakers rated and advertised their engines in brake horsepower (bhp), frequently referred to as SAE gross horsepower, because it was measured in accord with the protocols defined in SAE standards J245 and J1995. As with other brake horsepower test protocols, SAE gross hp was measured using a stock test engine, generally running with few belt-driven accessories and sometimes fitted with long tube (test headers) in lieu of the OEM exhaust manifolds. The atmospheric correction standards for barometric pressure, humidity and temperature for testing were relatively idealistic.

    SAE net power

    In the United States, the term bhp fell into disuse in 1971-72, as automakers began to quote power in terms of SAE net horsepower in accord with SAE standard J1349. Like SAE gross and other brake horsepower protocols, SAE Net hp is measured at the engine's crankshaft, and so does not account for transmission losses. However, the SAE net power testing protocol calls for standard production-type belt-driven accessories, air cleaner, emission controls, exhaust system, and other power-consuming accessories. This produces ratings in closer alignment with the power produced by the engine as it is actually configured and sold.
    Last edited: Dec 29, 2012
  15. CraigKrage
    Joined: Nov 1, 2007
    Posts: 421

    from central IL

    I've seen alot of 400+ HP cars turn into 200+ HP cars once they get on the Heartbreaker known as the Dyno.
  16. 2-TONED
    Joined: Jan 31, 2005
    Posts: 1,683


    HATE to say it!
    but like the new car makers say: the OLD fast is the NEW slow!!
  17. lawman
    Joined: Sep 19, 2006
    Posts: 2,665


    Wow, Like that was alot of good info fellow's !!!!
  18. 4 pedals
    Joined: Oct 8, 2009
    Posts: 784

    4 pedals
    from Nor Cal

    Run it on the dragstrip. All lies disappear.

  19. gimpyshotrods
    Joined: May 20, 2009
    Posts: 18,365


    Beyond all of the computing and reporting differences, everything new has a recently designed engine, of a vastly more efficient design, and has digital powertrain (not just engine) management. More power, AND less fuel consumption. Might not be as much power, but more per inch/cc than was possible before.
  20. Gotgas
    Joined: Jul 22, 2004
    Posts: 6,977

    from DFW USA

    My daily driver 2012 Mustang 5.0 has drag radials and no other modifications. It is advertised to make 412 at the crank and lays down 390 to the tires. It runs 12.24 @ 114.5 and is governed to 145mph, which is a LOT faster than just about anything you can point to from the musclecar era, even if you put them on modern tires. It looks good (for a modern car), it rides good, turns good, stops good, and ... oh yeah, it's also quiet and comfortable.


    The old stuff is still more fun.

    Even with a bunch of old performance parts, there's still a good chance that a new car or truck will outrun and outtow the old stuff. I wouldn't be surprised... in fact, it should be expected. But it doesn't matter. Enjoy your old tin!!
  21. And after all that, there's 40 plus years of suspension design to consider. Paralell leafs aren't exactly hi-tech.
  22. Truckedup
    Joined: Jul 25, 2006
    Posts: 4,134


    So you think the Hemi cars coming off the factory line had anything near 580 HP? In their day,tuned but stock Hemi car with headers gears and slicks ran mid 12's at best....that's no where near 600 hp.You think Landy massaged the engines and called it "blueprinting"? :D
  23. All I know is Landy professed it WAS stock. That was kind of the point of the whole deal...
  24. tfeverfred
    Joined: Nov 11, 2006
    Posts: 15,792


    Sounds like a "your results may vary", type thing. I've read OPINION that the factories fudged the numbers for insurance purposes, but I have not read a FACTUAL article on the subject. Yet, it makes sense.

    There are so many factors to consider in a comparison like that. As far as which is faster? I think that a late 60's Hemi Challenger would be hard pressed to beat a 2012 Hemi Challenger. Even though the 2012 isn't really a TRUE Hemi, the advantages of aerodynamics and an onboard computer would put the new Challenger in the winners circle.

    On a side topic, it seems what hurt hotrods in the late 60's were the factory cars. And now the new cars are comparatively faster and more efficient than the late 60's cars, so fate has popped up it's head again. But like a new Challenger owner told me, "You're having more fun than me AND you don't have a 5 year note."

    You know what pisses off the new muscle car owner? When a homebuilt hotrod gets more attention than his $50,000 Mustang or whatever. I see it every day. THAT'S what we have to remember and be proud of. INDIVIDUALITY. Shit, there are NURSES at the Veterans Hospital, here in Houston, riding arond in new 'Vettes. Anyone can have one. A person could work at Mac Donalds and live at home and have a new Hemi Challenger...... just like the one on every corner.

    About the only advantage in a 1/4 mile race a hotrod could have, would be power to weight. A new Hemi Challenger against a like motored Model A? My moneys on the Model A. BUT, he better be able to hook up.
  25. Dane
    Joined: May 6, 2010
    Posts: 1,351

    from Soquel, CA

    [​IMG] Don't confuse me with the truth! [​IMG]

  26. Gotgas, I totally believe your 1/4 mile time and speed, but only a 22 H.P. parasitic loss through the drivetrain is pure B.S., and I'm not saying it's you brother. If your car was on the chassis dyno, someone needs to recheck his calculations or his eyes. Again not calling you out personally but this is not right, TR
  27. slammed
    Joined: Jun 10, 2004
    Posts: 8,151


    Indeed, 80-100 hp is a rule of thumb lost through the drivetrain.
  28. ... and then there is the diffence between flywheel HP and RWHP.

  29. Yes sir that is what we mean by " parasitic " loss. The power it takes to turn gears, shafts, differentials, even move and displace fluids.

    That said, FORD might have purposely been rating the flywheel numbers on the low side too for insurance reasons or a Big Brother watching out for our safety type of situation. That is why I wasn't calling out Gotgas, but I run engine and chassis dynoes and something isn't right somewhere. His Mustang might be closer to 500 flywheel H.P., and Ford has rated it lower for whatever reasons, TR
  30. black 62
    Joined: Jul 12, 2012
    Posts: 1,895

    black 62
    from arkansas

    i was wondering the same thing when i saw the times all these new cars were running--so i took my 50year old car out and did some research at some stoplights ...ram air firebird, two 5.0 stangs ,and a hemi pickup---all wanted a re-match-- average advantage 1.5 cars after two gears---went to strip... mid to high 12's in drive----there were plenty of
    stangs and camaros faster ...bigger tires weren't the only reason that factory stuff is fast off the showroom floor

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