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Torque or HP ????


Mel4fun
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Merry Christmas and Happy Holidays from OHIO!

 

yeah, Sweat Christmas and VroomVroom Holidays from..... and ohaiyo kojaimatsu......

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no wurries mate, when you come back (27/12??), we will organise the first ever MCF Conference cum Workshop on "Torque vs HP"..... the venue will be: open air conference hall at Jln Kayu, where the most kayuiest kayuists congregate......... [laugh][laugh] ......... breakfast n supper included, fee per head: 5 cents (as everyone attendant is expected to put in his/her 5 cents' worth of trash...... [thumbsup] .........Guest speakers are:- 10 times expressways grand prix champ - Presea, F1 offficial engineer - TB, Prof Doc Mike, etc etc (not in order of trashy ability or knowledge), plus, wait for this: Chairperson of Conference Datin An.......... oopppps [lipsrsealed][lipsrsealed]

Edited by Super7
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above peak torque....torque levels are still quite high....combined with increasing horsepower (which would be approaching peak power)... that would create more acceleration than a car should have when taking a corner.

So if a car were to enter a corner above peak torque.....applying too much throttle would tend to force extra acceleration, and that would result in an understeer situation (for FWD cars)....and that is not desired.

 

Below peak torque......with the engine burbling just below the powerband....the car would be ready for accelerating out of the corner..........starting at the apex... [thumbsup]

 

driver skills aside.....traction in a corner/bend is most important.....this is to allow you to maximise the overall power put down to the wheels when one side has more grip than the other, with the car transfering it's weight from side to side.

 

Of course if you're in a 4WD car.....then that's another matter... [laugh]

 

so when is your Turbo R coming?>.... [sly]

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no lah, still in good 'ol singapore..... heard this year eastern part of north america is cold...... any way, air tickets are expensive and hard to get (too late now)..... no plan to go boston, maybe until he graduates in 1 n half years' time....... you can then drive your 7 litre mean machine to MCF meetup in USA, juz two of us [:p][:p]

Edited by Super7
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The weather here is cold but abnormal, like today it's actually getting warmer! The forecast shows some rain coming so temps will go up for two days then snow. [sweatdrop]

 

My "7 litre"??? Yeah 3.0 from the Taurus and 4.0 from my belly! [laugh]

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It is advisable to shift at peak power (@redline) as the RPM is going to drop after you downshift. So when the RPM drop, most likely it'll fall to the RPM near to the peak torque.

If you shift at peak torque, most likely you'll drop out of the torque band as the rpm reduces.

 

To reduce the effect of such shortcoming, get yourself a car with flatter torque curve. NA car that comes with cam phasing valve control like VVT-i, VVTL-i, i-VTEC or VANOS has flatter torque curve than conventional engines.

 

-----------------------------------------------------------------------

 

Torque (ft-lb) = P (HP)* 5252 / RPM

 

As RPMs get higher, there is less torque for a given amount of power. For example, compare two engines that make 250HP at their peaks. The first peaks at 5,000 RPM, the second at 7,000 RPM. At the time the first engine is making its peak horsepower, it will be making 263ft-lbs of torque. Where at its power peak, the second engine only makes 188ft-lbs of torque. Even though both engines boast the same peak power, the first is going to have higher torque the majority of its power band, meaning quicker acceleration. This is complicated some by gearing, though, as the second engine has a much longer range of operation before it needs to shift to a slower gear.

 

 

OK.....something that bugs me.

 

Imagine this, if a particular car has its max torque @ 3800rpm, whereas its max BHP @ 6200 rpm.

 

If I'm coming out from a corner to a straight with a gentle uphill, do I hold on to the rev up till the redline and shift or do I shift after 1000 rpm after the max torque ??

 

What should I do :-

1) I rely on the BHP to pull the car all the way (rev till near redline then shift)?

 

2) I shift near the max torque rpm ??? (so as to maintain max torque throughout the power band)

 

Any pointers from forum gurus ????

TIA [:p]

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no wurries mate, when you come back (27/12??), we will organise the first ever MCF Conference cum Workshop on "Torque vs HP"..... the venue will be: open air conference hall at Jln Kayu, where the most kayuiest kayuists congregate......... [laugh][laugh] ......... breakfast n supper included, fee per head: 5 cents (as everyone attendant is expected to put in his/her 5 cents' worth of trash...... [thumbsup] .........Guest speakers are:- 10 times expressways grand prix champ - Presea, F1 offficial engineer - TB, Prof Doc Mike, etc etc (not in order of trashy ability or knowledge), plus, wait for this: Chairperson of Conference Datin An.......... oopppps [lipsrsealed][lipsrsealed]

 

thank u very very much....deeply appreciated....i will be coming back on coming Sun, 22/12...but 27/12 sounds good to meet cos i need to do some catch up with family and friends as well.... [;)]

 

in fact, i have been working on the combustion backpressure kind of thing....and now is waiting to see if Shell is able to provide me a gasoline chemical composition so that i'm able to do a backward calculations to get the kind of backpressure....will update further on the findings....see u guys soon!!! [thumbsup]

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no secret project lah.....just wanna play with some figures and put it into practical....as u can see, it was observed that there is alot of backpressure created from 4-1 header as what turbobrick has mentioned.....there is always a possibility that we are able to reduce that kind of pressure through piping design....in my initial investigation, i reckon that its probably due to high turbulence flow from the exhaust stroke, which creates alot of surface friction due to the weird design of 4-1 manifold.....so there is always a possibilities to reduce that kind of turbulence flow through some design issues......

 

don't worry, i will definitely update u guys more abt the analysis...so far so good.. [thumbsup]

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Neutral Newbie
aiyo yo, cannot lah.....i prefer na car lah......anymore suggestions...

 

in fact, i did tot of doing the manifold.....say instead of 4-2-1, put it 4-1....but don't know what's the result to be like leh.....other than that, is either doing the remapping of ECU loh...but really no ideas lah... [confused]

 

Port-polish the the top cylinder head and increase the compression level slightly by grinding off a thin layer.

This way, you will get a more torque from your engine without compromising on your fuel consumption. Moreover you will get a very reliable engine if done PROPERLY.

 

If you have the cash, blueprinting the engine is the best way to get more hp and torque from the engine and reliability also.

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gosh, that's a very big hat that u are giving me....i really appreciate that but i guess it's too big a hat for me to put on......anyway, thank u very very much for the complement.... [:)]

 

will do my utmost best to extract the assumingly most power from our decent engine..... [:)]

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