I Got my first Dyno and what an odd set of No.s

Discussion in '2005 - 2009 Specific Tech' started by 05SonicBlueGT, Jun 29, 2005.

  1. 05SonicBlueGT New Member

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    I just got my 1st dyno with 87 oct. Gas V8, Stick, Mac CAI, Predator and what a odd set of no.s Max RWHP 232 @ 5450 RPM, and 374.7 Max Torque. I told the guy your Mustang Dyno has something wrong with it, he said it was working fine, it must be the weather cond.
    Temp.93.8 Deg
    Press. 29.84
    Humdtiy84%
    Has anyone ever seen no.' like this or do you think his mach. is hosed.
    Is there some where on the Web to convert weather cond. to see what difference it makes???
  2. Nolyaw Banned

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    The Hp number is down due mostly to how hot it is (the car acts stupid when the engine gets hot) and the low octane fuel. The torque number is absolutly wrong. 274 maybe, but not anywhere close to 374. Get your money back. A strong stock car with 93 octane runs about 266 hp under normal conditions.
  3. billy_tripper New Member

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    So would running a race in 95 degree weather be that much slower? Just wondering. Also, does this affect all cars the same way (ex. an srt-4)
  4. dozlert New Member

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    My dyno torque dropped 14 foot pounds when the temp went up to 95 degrees. LS1s don't do well in heat.
  5. FallujahMedic New Member

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    SRT-4 hehe, titter, snort. Is that a REAL car?
  6. vacooley New Member

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    Pressurized motors tend to be more sensitive to heat. Not always but in general. So, you would probably have an advantage in heat over a smaller turbo motor.
  7. 300bhp/ton New Member

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    yeah those numbers don't look right.

    with 300/320 rated by Ford I would expect the hp and torque numbers to be closer together. Is your car stock or modified (even slighty??).

    As a rule bhp is made via a calculation from torque and rpm. If you know where the PEAK torque was or have a copy of the graph with the torque readings for say every 500rpm increment you should be able to plot your own graph on Excel using the formula for bhp (ist out there on the net so you'll need to do a search as I can't remember it.)

    This way you can confirm if the bhp plot is correct according to the torque.

    Other possibilites could be that the car was dyno'd in the wrong gear, if it was dyno'd in a gear that was not 1:1 then the torque should show up ok but the rpms would be different giving a lower bhp reading (if the gear was higher than 1:1, say 1.86:1).
  8. fin1 New Member

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    The tq vs hp number variance is odd. The Mustang Dyno is loaded dyno so the rwhp number looks about right.
  9. 05SonicBlueGT New Member

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    It was dynoed in 4th gear starting at 45 mph up to 122mph max hp was at 110 mph max torque was at 95mph
  10. Power Surge Founding Member

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    Mustang dynos measure differently than Dynojets do, so if you are trying to compare your numbers to everyone else's Dynojet numbers, they WILL be lower.

    Torque is calculated based on engine rpms and wheels speed. He probably didn't have the tach setting right on the dyno for your car.

    Hope this helps.
  11. 05SonicBlueGT New Member

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    Do you know what the formual for torque is? I have all of the no.s. RPM's, MPH!
  12. 01-0471 New Member

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    My dad had his Viper GTS dynoed on a mustang dyno, and it was the sameway yours was low horsepower and high torque. I think it was something like 340rwhp and 575 rwtq.. A viper should pull like 410rwhp and 450rwtq.
  13. 300bhp/ton New Member

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    This is only a guess and working fro memory with rather impresice figures and assumptions. So don't read to much into it.

    BHP = (torque x rpms) / 5250

    So

    Torque peak of 274.7 (assumung lb ft) @ 95mph in 4th. I reckon thats about 4702rpm

    (274.7 x 4702) / 5250 = 246rwhp

    This does not mean this is correct and the dyno s wrong. It just mearly highlights how inaccurate it all is. As there are far too many variable and standards.

    Dyno is for tuning NOT power readings. Hence the phrase 'dyno tune'!

    So you know have 2 possible numbers to work from, but regardless of which figure you choose your car will still be producing the same amount of power and have the same performance envelope.

    Numbers are just that, numbers. They don't really mean a great deal in terms of real world performance.
  14. zinn New Member

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    sounds like the tach was off. the dyno mesures power and converts that into torque. so if the dyno thought your car was at around 2900 rpm but in reality your car was 5800 rpm putting out 322hp then you would get a over inflated torque number. im not sure about cars but i know on motorcycles it's not uncommon to get ignition spark on the power stroke and exhaust stroke so it's very easy to double or halve your rpm indication if you configure your test equipment incorrectly.
  15. 1LEThumper New Member

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    The settings might not have been correct either....if I rememember correctly the Mustang Dyno asks for vechical weight as well doesn't it? Were all the parameters entered correctly?
  16. 05SonicBlueGT New Member

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    It has the weight at 3650lbs.
  17. 2004redmach1 New Member

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    He is suppose to calibrate dyno once a week. Sounds like he didnt calibrate it.
    On my mustang dyno a stock 05' with 93 had 268 rwhp and 3 something torque. Go and get money back or get a re-run. And if he tries to shoot you **** let me know shop name and number.

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