What kind of motor characteristics are favorable for a road-racing car?

Discussion in 'OT Driven' started by 2DR Vette, Nov 12, 2003.

  1. 2DR Vette

    2DR Vette We don't freestyle the Eyes of Texas, Big Boy.

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    Well?

    I know for drag racing, you want the most HP you can get along with jsut enough torque to make it jump off the line.

    But what about road racing? If you were going to custom grind a cam for a track car, what charactersitics would you want? Plateau-flat torque curve? Power down low in the RPM range? Lower, but flatter HP curve?

    I know it'll vary on the car, but assume it's something liek a C5 or Supra or Mustang- ~32xx# RWD, Front-Engined street-type car. :)
     
  2. From what I've seen, people usually go for high lift/duration cams that are incredibly peaky, i.e. only make power from the last few thousand RPM to redline.

    Then it's just up to the driver to throw gears to keep it in the high revs.
     
  3. Jaron95

    Jaron95 "Gattai" dattou?!

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    Peaky powerband... :drool:
     
  4. Swarol

    Swarol Guest

    Depends on the driver, but typically people try to stay at higher RPMs, so obviously that's where you'd want most of your power to be.
     
  5. 2DR Vette

    2DR Vette We don't freestyle the Eyes of Texas, Big Boy.

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    What kind of motors? :confused:

    I know in the Trans-Am series cars, the powerbands rnage from 4000-8000RPM. IN a larger V8, why would you ever want anything that peaky?

    Maybe if you had custom gearboxes where you could change up the cogs or something to make sure you had the right powerband all the time, but in a street-ish car with a fixed-ratio gearbox? :dunno:
     
  6. tolomei

    tolomei Leaving Las *****-Vegas

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    That it's fast? :eek3:
     
  7. dimo

    dimo New Member

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    4wd conversion :dunno:
     
  8. Swarol

    Swarol Guest

    It doesn't really matter all that much, only that you know where the powerband is and can shift accordingly. Since it's easiest to hear when you're approaching redline, that's some of the reason people try to get power there.

    However, if you want it low, do it :dunno: Be aware of your powerband and gear ratios and shift to keep in your powerband as best you can.
     
  9. 2DR Vette

    2DR Vette We don't freestyle the Eyes of Texas, Big Boy.

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    Only for those that need a crutch and can't drive a real RWD racecar. :o
     
  10. ace3

    ace3 mouthify my wang.

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    i wouldn't want it in a fucking Corvette, that's for damn sure.




    :fawk:
     
  11. dimo

    dimo New Member

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    :ugh2:
     
  12. Swarol

    Swarol Guest

    :rofl: :bigthumb:
     
  13. 2DR Vette

    2DR Vette We don't freestyle the Eyes of Texas, Big Boy.

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    I guess that's really the trick. It doesn't matter, as long as the dirver can get the most power to the ground when they need it. :)
     
  14. 2DR Vette

    2DR Vette We don't freestyle the Eyes of Texas, Big Boy.

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    At least I've GOT a car that I can take to the track. :fawk:
     
  15. Swarol

    Swarol Guest

    That, and since it's a street car, you don't want a really narrow powerband or you're going to have to shift above/below it.
     
  16. dimo

    dimo New Member

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    as do i :)
     
  17. tolomei

    tolomei Leaving Las *****-Vegas

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    Fixed. :eek3:
     
  18. dimo

    dimo New Member

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    nice work
     
  19. Swarol

    Swarol Guest

    Your previous posts suggest you believe AWD is superior to RWD for road racing. If this is true, your opinion is invalid and to be ignored :)
     
  20. 2DR Vette

    2DR Vette We don't freestyle the Eyes of Texas, Big Boy.

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    The Heep won't make it half a lap at a decent pace without rolling over. :o
     
  21. 2DR Vette

    2DR Vette We don't freestyle the Eyes of Texas, Big Boy.

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    :werd:
     
  22. 2DR Vette

    2DR Vette We don't freestyle the Eyes of Texas, Big Boy.

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    Everybody spins from time to time. :dunno: Nothing wrong with that if you learn from it. :fawk:
     
  23. Early Apex

    Early Apex Guest

    Anything and everything. I've seen race cars built around 1.8l and 440ci engines, rotaries, even diesels.

    I think in general you want a lightweight but durable block and low rotational inertia: lightweight crankshaft, flywheel, etc. You want an engine that picks up revs as quick as possible, and a very high redline doesn't hurt; if you don't have to short shift on a runup to a tight turn, you save a lot of time.
     
  24. The only real motors I have actual experience with are e30 m3 motors, so those are relatively small displacement high revving varieties.

    But it's been said before, it all comes down to driver preference, but just remember: if, for example, you're making 400 clean ft*lbs from 3-7krpm, that's still less hp than making 400 clean ft*lbs from 4-8krpm.
     
  25. nosaj

    nosaj OT Supporter

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    I have done a lil road racing. If your new you can find a class for any kind of car you can get. We have dynoed a ford festiva that made 78 horse to the rear wheels thats road raced. My bosses car is a mustang that makes over 600 hundred to the rear wheels and he has road raced that. THe car has drum brakes one the rear! It was crazy to see this thing blow past the supercars on the rear straight away at gingerman. You had to really be carefull on the turns.We spun more than once, it was fun!
     

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