Got torque?

Discussion in 'SRT Hellcat Performance' started by Supercharged_Fun, Mar 5, 2016.

  1. Supercharged_Fun

    Supercharged_Fun Silver Member

    Joined:
    Jun 25, 2015
    Messages:
    667
    Likes Received:
    199
    Trophy Points:
    153
    Vehicle:
    Challenger SRT Hellcat
    Okay, ladies and gents.
    I have to ask as I have been reading/researching a lot of cars that hit the dynos. Why is it that the Hellcat can put some crazy HP to TQ ratios? What I mean is, how does the Hellcat be able to put out so much torque? Not only in stock form, but in modified form as well. The torque numbers look great when seeing these cars being dyno'ed as opposed to some other brands that look the HP to TQ ratio.

    **I know HP and TQ doesn't mean you are the fastest drag racer or whatever. It is more than HP and TQ that wins races. I'm not concerned with that as I don't track or road race my vehicles. Just simply very interested as to why these beasts can get their torque numbers so high. Thanks!
     
  2. DGatzby

    DGatzby Gold Member Hellcat Car Club HCC Charter Member Midwest Regional Pres.

    Joined:
    Jan 16, 2015
    Messages:
    2,882
    Likes Received:
    1,453
    Trophy Points:
    598
    Location:
    Twin Cities, MN
    Vehicle:
    Challenger SRT Hellcat
    It was an exceptional day, planets were aligned, car was the perfect temperature, the D/A was so low it was cheating, but mine put down 670 hp and 666 ft-lb one morning. We even had other members of the forum who saw it. Others were within 20-30. But hell ya, these are monsters!
     
    • Like Like x 3
  3. Supercharged_Fun

    Supercharged_Fun Silver Member

    Joined:
    Jun 25, 2015
    Messages:
    667
    Likes Received:
    199
    Trophy Points:
    153
    Vehicle:
    Challenger SRT Hellcat
    That's insane for a stock car! Dynamite numbers. Congrats!

    I'm just wanting to know why the torque on these cars are so high, whether it be stock or modified. What makes these cars put out great torque numbers?
     
  4. Lord Hellcat

    Lord Hellcat Gold Member Hellcat Car Club Gold Supporting Member HCC UK President HCC Charter Member

    Joined:
    Jan 6, 2015
    Messages:
    1,486
    Likes Received:
    641
    Trophy Points:
    463
    Location:
    UK
    Vehicle:
    Challenger SRT Hellcat
    The very clever engineers at Dodge SRT
     
    • Agree Agree x 3
  5. Obiefox

    Obiefox Silver Member

    Joined:
    Aug 22, 2015
    Messages:
    376
    Likes Received:
    97
    Trophy Points:
    138
    Location:
    Cincinnati
    Vehicle:
    Challenger SRT Hellcat
    Ummmm....Positive displacement supercharging.
     
  6. ArchGE

    ArchGE VIP Hellcat Member

    Joined:
    Feb 29, 2016
    Messages:
    271
    Likes Received:
    93
    Trophy Points:
    98
    Location:
    Parker, Colorado
    Vehicle:
    Challenger SRT 392
    Not an engineer but am guessing drive train gearing has a lot to do with torque. Add some crazy horse power and zoom zoom.
     
  7. Supercharged_Fun

    Supercharged_Fun Silver Member

    Joined:
    Jun 25, 2015
    Messages:
    667
    Likes Received:
    199
    Trophy Points:
    153
    Vehicle:
    Challenger SRT Hellcat
    There's got to be some specific reason as to why there's a ton of torque.
    Just curious because when I see the S550's getting Whipple supercharged, the HP is OVER 700 at the wheels and the TQ is pretty low, like 590 at the wheels. Just want to know why and how the Hellcat can pull that off, bring numbers well over 650 at the wheels when modified.
    Maybe someone with some serious "engine know-how" can explain it to us.
     
  8. Mills

    Mills Silver Member

    Joined:
    Jan 28, 2015
    Messages:
    589
    Likes Received:
    133
    Trophy Points:
    153
    Location:
    Airdrie, Alberta
    Vehicle:
    Challenger SRT Hellcat
    The power shape of an engine are based on many things. Some examples: bore, stroke, rod length, head flow, head cross section / velocity, cam profiles, intake tracts, exhaust tracts,A/F and timing curves, etc. The engineer needs to optimize everything but ensure everything works well with one another. OEM guys have a harder time as they to do all that, yet keep emmissions and gas mileage optimized as well. The Hellcat motor is an amazing piece of equipment. I have little experience with boosted engines. I gotta admit my knowledge and experience with new stuff also lacks.

    If I use my go-to motor - the Mopar Big Block - there are various reasons it was a great motor.

    Bore: mopar always used large bores. Compared to a BB 454 Chevy, a 340 Mopar had the same bore size. This ensured the valves would not be shrouded nearly as much to improve air flow. Ensures proper flow in and out, as well as flame travel over the larger surface

    Stroke: Mopar used relatively short strokes compared to Chevy, and long strokes make torque...yet I would say the mopar engines were better known for their torque then HP - why?

    Rods: mopar always used the longest rods. Many benifits from longer rods. Many old time chev race guys (ie Yunick) knew this was a downfall of chev and would change rods. Simple things like less wall loading thru the cycle to increased time at TDC for sustained cylinder pressures (and torque) result. Think of a big stroke / short rod engine vs a short stroke / long rod and the time spent at TDC and the acceleration down the bore after that

    Head: one thing chev had were really good flowing head compared to the BB mopar. Yet it generally didn't make more power. The flow generally came with large port, large cross sections, and lazy port velocity. A killer for low end torque but good for high end power. Going back to the long stork and short rods and the acceleration of the piston as a result - this "masked" the mismatched design of the components and the lazt port velocity. The very small ports of the mopar made great velocity and massive low end torque. Handicapped it up high but not many guys back then on the street where the wars were fought ever really stretched th legs like today. Power peaking at mid 5's was perfectly fine

    Cam: not going into huge details on lifts and durations...but Mopar had milder cams in durations which also helped with cylinder presures. Chev did have better rocker arm ratios to help gain better lift #'s. But the actual cam and lifter itself: Chev used a. 842 lifter dia and Mopar a. 904. This is significant - the design of the cam allows closer to that of a roller (fast snap off seat to max lift where it can stay around max lift longer and snap back down for the same seat to seat timing). Massive advantage for mopar on the old flat tappet stuff. Again something Chev race guys realize and try to rectify.

    That is but a scratch of the surface and not too in depth examples of engine design, the theory, etc. There are tons more

    Mopar may not have had the best body designs (to each his own...since I think so), best paint, quality control, etc etc...(and some of these issues still exist today) but they had the best powertrains hands down. Apples to apples - leaving OEM architecture alone - a 340 will always beat a 350 or 351. A 440 will always beat a 454 or 460. Give us a racy solid cam, and a 383 will always beat a 396 (probably chev's best engine) or (laugh) a 390. Going to the race side, a 426 will always beat a 427 or 428/429
     
    • Useful Useful x 3
    • Like Like x 1
    • Winner Winner x 1
  9. 16SRT

    16SRT VIP Hellcat Member

    Joined:
    Feb 20, 2016
    Messages:
    420
    Likes Received:
    121
    Trophy Points:
    73
    Vehicle:
    Charger SRT 392
    No replacement for displacement. Add to that a belt-driven supercharger...

    Your quoted S550 is a turbo'd 4.7L, if I'm not mistaken. Small displacement, and a turbo that doesn't provide nearly enough boost in the lower rev's.
     
  10. Supercharged_Fun

    Supercharged_Fun Silver Member

    Joined:
    Jun 25, 2015
    Messages:
    667
    Likes Received:
    199
    Trophy Points:
    153
    Vehicle:
    Challenger SRT Hellcat
    No, I'm talking about the new Mustangs, the S550 platform. Most guys are running Whipple superchargers on them and are making well over 720RWHP and about 590RWTQ. I was wondering why the SRT engines can have more torque than most cars that are modified or supercharged. When seeing the Hellcat get mods, you see a nice jump in the TQ numbers and curve, higher than most others.

    Thanks for everyone's response here. I appreciate it.
     
  11. 16SRT

    16SRT VIP Hellcat Member

    Joined:
    Feb 20, 2016
    Messages:
    420
    Likes Received:
    121
    Trophy Points:
    73
    Vehicle:
    Charger SRT 392
    hah... didn't even know there was a Mustang called "S550". Strange that they'd even use that as a model number, since there's already a much nicer car using this badge:

    2014 Mercedes-Benz S-class / S550 - First Drive Review

    Honestly haven't looked at a Mustang since I was old enough to know better, but does this change my response above? Aren't those Mustangs still 5 liter? Displacement.
     
  12. Supercharged_Fun

    Supercharged_Fun Silver Member

    Joined:
    Jun 25, 2015
    Messages:
    667
    Likes Received:
    199
    Trophy Points:
    153
    Vehicle:
    Challenger SRT Hellcat
    Yes, the new Mustangs are 5.0 engines.

    The "S550" is just the platform. No specific Mustang is called the S550. It's from model year 2015-??? It's the 6th generation Mustang.
    I currently have a S197. 5th generation.
     
  13. cat8you

    cat8you Silver Member

    Joined:
    Jul 12, 2015
    Messages:
    221
    Likes Received:
    44
    Trophy Points:
    138
    Location:
    michigan
    Vehicle:
    Challenger SRT Hellcat
    really?its 302 short stroke short rod small bore.big tq ya rite.
     
    • Like Like x 1
  14. Supercharged_Fun

    Supercharged_Fun Silver Member

    Joined:
    Jun 25, 2015
    Messages:
    667
    Likes Received:
    199
    Trophy Points:
    153
    Vehicle:
    Challenger SRT Hellcat
    I think you're confused with the title of the thread. :confused:
    Did you even read any posts in this thread?
     
  15. DGatzby

    DGatzby Gold Member Hellcat Car Club HCC Charter Member Midwest Regional Pres.

    Joined:
    Jan 16, 2015
    Messages:
    2,882
    Likes Received:
    1,453
    Trophy Points:
    598
    Location:
    Twin Cities, MN
    Vehicle:
    Challenger SRT Hellcat
    Top NHRA engines now? MOPAR because they make more power!
     

Share This Page