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Technical What's the deal with Horsepower Lately?

Discussion in 'The Hokey Ass Message Board' started by F-ONE, May 26, 2018.

  1. F-ONE
    Joined: Mar 27, 2008
    Posts: 2,767

    from Alabama

    Have any of you noticed the large numbers discussed? Sums like 400....500....600 or better are being dropped like hat in conversation.
    Recently a guy had a crammed stockish 352.... got 500 plus at the dyno. OK.o_O

    I have no reason to doubt the guy but have horses gotten smaller?

    A 300 horse engine? why that's a pip squeak.:rolleyes:

    I remember when....Horsepower was elusive?....hard to get? unproven claim?.....just a number? estimate?.... baloney....
    I don't know, it just seems that high numbers are thrown around like some reality TV show. I do not know if I buy it.

    Pro.....semi pro racers, yeah. Those guys do that for a living or....really live it.

    Then there is these guys with some beater wanting add an engine that quite literally has the same HP as a WWII fighter. Like it's easy or expected.

    My philosophy has always been that most HAMB friendly cars are out of tune. Stock is the base. Back then most cars were tuned for overall reliability. To keep them in tune even at the factory setting meant proper and regular adjustment. Get it it right in stock form and you are way ahead of most. Then....go further.
    Each little improvement was a gain but not a big big gain.....not like the numbers mentioned today.

    It's the size of the horse that counts? Back in 73 or so they changed how HP was measured. Instead if crank HP it was rear wheel or something like that. So...a 250 HP engine in 1965 was a 180 HP engine in 73. The horses got bigger? Have they got small again?
    zzford likes this.
  2. gimpyshotrods
    Joined: May 20, 2009
    Posts: 18,145


    No change in size of a pony.

    Technology got better.

    That is how I have a 200-inch engine, with 199-hp (crank, actual measurement), and a 354-inch engine that will likely be at about 650(known build spec).

    The secret? Modern camshafts, CNC porting, lightweight rotating assemblies, and 100% digital engine management.
    402BOSSMAN, OahuEli, brad2v and 6 others like this.
  3. Hot Rod Rodney
    Joined: Jun 20, 2014
    Posts: 160

    Hot Rod Rodney
    from USA

    During the gas crisis of the 1970s and resultant down-scaling of performance, I recall factories changing the way they measured HP to give LOWER numbers. Engines that had formerly been rated at, say 300 hp were now rated at 175, etc. This was during the period when OEM speedos were changed from reading 120 mph down to 80 mph. The whole scheme was to de-emphasize the prevailing performance mentality of the 60s horsepower wars to a more politically correct mileage mentality. I don't recall now how they changed the measurement - FHP to BHP perhaps? - but I did read the details in a reputable auto-related publication.
    loudbang likes this.
  4. gimpyshotrods
    Joined: May 20, 2009
    Posts: 18,145


    Old: Gross HP, no accessories, no exhaust restrictions.
    New: Net HP, all accessories, stock exhaust, emissions stuff. Basically "as-installed" int he car.
    swade41, brad2v, 6-bangertim and 6 others like this.

  5. They went from gross HP (at the flywheel, no engine-driven accessories) to net HP (all accessories installed). It also didn't help that compression ratios were lowered across the board due to the coming of unleaded fuel and the requirement that all engines had to run on it. You have to remember, initially unleaded was only available as a low-octane 'regular', as leaded gas remained available in both 'regular' and 'premium' octanes to service existing older cars. As the leaded fuel was phased out, it was only then that higher-octane unleaded became available and performance returned to Detroit....
    brad2v, 55styleliner and loudbang like this.
  6. gimpyshotrods
    Joined: May 20, 2009
    Posts: 18,145


    The change in horsepower ratings, and the lowering of output had noting whatsoever to do with political correctness. PC is a modern term, which is slang for stopping being a jerk to other people.

    The insurance companies drove the nails into the coffin of the muscle car era. It was over before OPEC cut gasoline supplest to the US in 1973. The government did not largely take sweeping action until 1978, by mandating CAFE standards (Corporate Average Fuel Economy, aka: fleet average) and by then, the horsepower wars were long over.

    CAFE standards are now why most automakers make and sell electric vehicles, and hybrid vehicles, and sell them at a loss. They do that, because those vehicles enable them to meet CAFE standards, while selling hugely profitable trucks and SUV's. They make back tenfold what they lose on an EV and a HV, with ease.
    XXL__ and squirrel like this.
  7. coreythompsonhm
    Joined: Jul 16, 2012
    Posts: 68


    What is able to be done because of cnc, digital monitoring and contol of fuel/ignition, etc, is why we can get such high horsepower numbers. Modern manufacturing technologies have also improved as well.
    pitman and loudbang like this.
  8. Torana68
    Joined: Jan 28, 2008
    Posts: 1,253

    from Australia

    As there always has been there are people who sware they have XXX Hp but actually have half that. Then there are the dyno operators who play with the Dyno settings to boost their special whatever........ there is a car show down here with the opportunity to have your cars Hp proven, a lot drive away dissapointed (especially a Po....e owner who spent $$$$ with his fav tuner only to have less Hp than last year )
    RMR&C and loudbang like this.
  9. chevy57dude
    Joined: Dec 10, 2007
    Posts: 6,326


    Gimpy's 354 engine can make almost 2 HP per cubic inch. That's impressive. In 1957, Chevy did what Chrysler already achieved: 1 horsepower per cubic inch. This was big news. Now the automakers have the emissions systems and injection all sorted out. Heads flow like nothing before. Double humps just can't compete with LS technology for example.
    There's always going to be the bullshitters throwing numbers around.
    The real way to know your power is to dyno the engine. Use a reputable machine shop. The man I go to builds many, many engines for local racers. Guys who come back because the win. A lot. He is legit and has a wonderful reputation.
  10. Happydaze
    Joined: Aug 21, 2009
    Posts: 1,134


    I thought real dynos were 1/4 mile long, and 1/4 mile is still 1/4 mile, isn't it? Well yeah, but now it can also be 1000 feet ;)

    INVISIBLEKID, belair, dan31 and 2 others like this.
  11. chevy57dude
    Joined: Dec 10, 2007
    Posts: 6,326


    782 horsepower divided by 489 cubes is 1.6 hp per cubic inch.
    This is how I learned for sure what my combo makes.
    *Edit - also 697 lb/ft of torque
    Last edited: May 26, 2018
  12. gimpyshotrods
    Joined: May 20, 2009
    Posts: 18,145


    Forced induction works wonders.
  13. Hot Rod Rodney
    Joined: Jun 20, 2014
    Posts: 160

    Hot Rod Rodney
    from USA

    Stopping people from being jerks is called "manners" and "courtesy." Political correctness is much more insidious. It's when one group attempts to shame another for their particular ideology in order to pressure them into conformity. And although it's true that the term "PC" wasn't invented yet, the concept certainly was alive in the 1970s automotive culture. High-performance cars and their drivers became stigmatized, and gas-guzzling vehicles were very much frowned upon by a sanctimonious culture in an attempt to force change in the public's way of thinking through peer pressure and shame - what we now call "political correctness."
    Last edited: May 26, 2018
    Thor1, tractorguy, Blues4U and 21 others like this.
  14. clem
    Joined: Dec 20, 2006
    Posts: 3,360


    We’re not living in the seventy’s any more.
    Computers, turbochargers, better engineering, better technology makes for better results.
    My son’s OT street legal car, makes over 4hp per cubic inch, if I have done the maths correctly. 745 hp off a 3 litre motor. ( at rear wheels, on a dyno ).
    Last edited: May 26, 2018
  15. Deuces
    Joined: Nov 3, 2009
    Posts: 20,121

    from Michigan

  16. Some of the older dyno guys I have worked with always have said, horse power is just a number, torque is what you feel in the seat of your pants. As far as racing goes, you can have all the HP in the world, but if you can not put it to the track it is useless .;)
  17. jnaki
    Joined: Jan 1, 2015
    Posts: 5,815


    Hey F1,

    Back in 1958, my brother bought the 58 black Impala with a 348 cubic inch motor that had 3 carbs. It was rated on the sticker as 280 HP. (It does not sound like much, but back then, it was one of the fastest, high horsepower motors.)
    We ran it at the drags and turned a good enough time(s) for winning the A/Stock class. We wanted more power, but could not get the 315 hp top of the power chain from our local Chevy dealer.

    After a few months of running stock with every extra adjustments we could make to still be in the stock class, we took it to a performance tuning shop that had a dyno. We were excited to see what the 348 would register on the rollers.

    So, our 348/280 HP factory designation should be power rated at the motor as the dyno showed only 190 hp at the rear wheels. So, what happened to the power ratings from the Chevy factory? It was Engine horsepower only, not rear wheel horsepower. It registered 90 hp less because of the drive train, gears, tire set up, etc.

    We were happy with the designation for our 348/280 hp from the factory as we did win a lot of trophies in A/Stock. But, within a year, then two, we were outgunned by the newer Chevy 348 motors: 320HP, 335HP, 350HP, etc. We saw the writing on the wall...

    So, most of the HP ratings we all see and hear on TV, 400hp, 500hp, and 600hp is estimated unless it is run on an engine dyno for ratings. Crate motors? Same story...

  18. boltupal
    Joined: Dec 27, 2010
    Posts: 278

    from western ny

    Horsepower is just a math equation. Torque talks and his king of the streets.
    zzford and slowmotion like this.
  19. southcross2631
    Joined: Jan 20, 2013
    Posts: 4,414


    A classic example. My 69 Camaro 396-375 4 speed 4.10 gear ran 14 flat 100 mph right out of the showroom. My son's new Mustang v-6 6 speed rated at 310 hp. Runs 14.20 at 96 mph and gets 26 mpg.
    That same Camaro with headers and traction bars and slicks ran 12.80 at 118 mph . So the horsepower rating back then was as high as the car companies could rate them and the customer still get insurance.
    My avatar had a .060 over 350 Chevy with 14.0 to 1 compression and AFR 220 heads and a crane .630 lift solid roller cam and a tunnel ram and twin 660 holleys and made 574 hp at 7200 rpm on an honest dyno. It ran 9.80's in the quarter.
    Blues4U, mad mikey and chevy57dude like this.
  20. BamaMav
    Joined: Jun 19, 2011
    Posts: 4,878

    from Berry, AL

    When I was a young man, I wanted all the horsepower I could get. Now that I'm an older fart, I want enough horsepower to get on down the road at a respectable rate, but I don't have to have so much that I can't keep rear tires on it. I want something that will accelerate better than a Ford Pinto with an automatic transmission yet less than a Pro Stock Camaro. I don't punch one as much as I used to, but when I do punch one, I want it to get up and go, not sit there and fry the tires.
  21. denis4x4
    Joined: Apr 23, 2005
    Posts: 3,732

    from Colorado

    The ‘31 Model A engine in my avatar came stock with 40HP at the flywheel. Chassis dyno showed 60HP at the rear wheels at 3500 RPM. All it took was $$$$. 7E0C0E0D-34BC-4A7C-84E0-A66E43DA60AF.jpeg
  22. I called summit racing, gave them my credit card # and got a dyno sheet with impressive numbers, they threw in the motor too. both hp and torque were in the 430 range. It’s that easy!
    greasemonkey54 and belair like this.
  23. chevy57dude
    Joined: Dec 10, 2007
    Posts: 6,326


    Southcross - what does your car weigh?

  24. jnaki
    Joined: Jan 1, 2015
    Posts: 5,815


    Hey D,
    Yes, money is/was an elusive thing as a teenager in the early 60s. Speed was limited to the amount of cash on hand. Isn't that for just about everything these days?

    "Money, get away
    Get a good job with more pay and you're O.K.
    Money, it's a gas
    Grab that cash with both hands and make a stash
    New car, caviar, four star daydream,
    Think I'll buy me a (football)drag racing team.." Pink Floyd

    Even later on, when we installed a Racer Brown Cam and lifters, a C&O Stick Hydro and other "go faster" speed parts, it was powerful, but not to the HP ratings from the factory race teams back then. We never did go back to the dyno with the new speed stuff was just cruising up/down the coast and racing from the drive-in parking lots again.

    But, if we were to start again on a build or upgrading a car, it would be with a new crate motor for more power. But, my wife is happy with her car that has 300 factory rated HP and low miles, for those sometimes needed, powerful bursts.
    Ron Funkhouser and Baumi like this.
  25. pitman
    Joined: May 14, 2006
    Posts: 5,050


    This conversation F1, is helpful. I'd forgotten all the cairns / events that marked the HP trail. Believe it is still 550 ft/lbs/sec.
  26. Many claims, are compensating for....something.
    Max Gearhead likes this.
  27. Gman0046
    Joined: Jul 24, 2005
    Posts: 6,260


    Jnaki, as I previously posted, I had the exact same black 58 Impala as yours a 280 HP three speed. At the time I thought the car was pretty quick and had loads of fun street racing and at the 1/4 & 1/8 mile tracks. In those days money was hard to come by for teenagers and spending cash on a dyno never entered my mind. I had enough trouble putting gas in the car. I'm totally surprised at the 190 HP readings on your dyno run. The car to me was way faster then something making 190 HP.

    jnaki likes this.
  28. Shamus
    Joined: Jul 20, 2005
    Posts: 1,204

    from NC

    Swapped the BBC 502/502 for "connect & cruise" LS3 480 in my OT - similar hp but no comparison in performance, reliability & economy (198 miles fill up 20 gal tank w/502 - 20+ mpg w/LS). Ain't technology great!!
  29. Lone Star Mopar
    Joined: Nov 2, 2005
    Posts: 3,078

    Lone Star Mopar

    Young guys w LS power laugh at these old 350hp 327's. That's when I buy em cheap and let em eat !

    Sent from my SM-J727T1 using The H.A.M.B. mobile app
    chevy57dude likes this.
  30. Fordors
    Joined: Sep 22, 2016
    Posts: 3,560


    Admittedly my coupe hasn't been out in a long time but when it was sometimes guys would comment "Gary Dyer says a 350 with a 6-71 puts out 700HP." Yeah right, but not this one. I always quoted 400-425 at the rear wheels because of the relatively loose blower, mild cam and highway oriented tune up. Hammer it in first and it is scary fast, I remember taking a friend for a ride once. Bill had a '71 Corvette that he had put headers, a cam, ignition work and a B&M 144 blower on. First we went out in his car and yes, it was pretty quick and for sure an improvement over stock. When we were in my car I gave him a taste of 1st and 2nd gear and his eyes got as big as saucers. I explained to him that was the difference between a 6-71 and a 144. Oh, and being at least 1000 pounds lighter helped too.
    mad mikey, Montana1 and chevy57dude like this.

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