How do I Add Torque ??

[autronicDSM]

nobody is selfish, more then one person said either get stickier tires or learn how to slip the clutch. these two right there should be able to let him lunch without smoking his tires.

and the conersation about hp and torque is quiet interesting, i've learned few things

 

[Stock90GSXT]

Originally posted by autronicDSM
nobody is selfish, more then one person said either get stickier tires or learn how to slip the clutch. these two right there should be able to let him lunch without smoking his tires.

and the conersation about hp and torque is quiet interesting, i've learned few things

it is quite interesting. preach on peepz.

 

[DSMJim]

Originally posted by autronicDSM
and the conersation about hp and torque is quiet interesting, i've learned few things

Now try and teach the HP vs. Torque think to a bunch of Honda guys. Good friggin luck. They will all say HP is everything under the sun except for a mathemitical calculation of torque at a particular RPM cause they dont like to hear that. I tried once and ended up kicking 2 guys outta the shop because they pissed me off so much.

They honestly think that HP at really high RPM is the best way to have it. I tell them a flat power curve that start low and stays constant is way better than one that just peeks at 9000rpm and they look at me like I have 3 heads.

I show them a dyno from a turbo car where it makes 340 wheel HP at 4600 rpm and holds over 300 almost to 7000rpm and over 250 to 8000rpm and they think it's the dumbest thing they have ever seen. THey ask how is that fast if it doesn't increase as the RPM increase as if it should only be 150hp at 3600rpm then build up. It just blows me away honestly they are so stupid.

 

[LaserRST]

Originally posted by nine5raptor
a lot of misinformation, but that is what life is, sifting through the junk that others leave behind.

btw 400 ft lbs tq making 6 hp will spin the tires.
Ff=NuS "maximum frictional force equals the normal force multiplied by the coefficient of static friction"
say you have 3300 lb car and uS=.50 with 12 in from the center of your halfshaft to the road. the maximum torque that can be applied to the halfshaft, with motion just impending, would be 1650 ft lbs. any more and the force exceeds the maximum static friction that can be developed by the tires in that given situation and you switch to kinetic friction (slippage)
horsepower will only give you and idea of how quickly you can move your mass, not how much power you make.

Uh I would like to believe that.... but I have never seen a 300 hp Diesel with 800ft lbs of torque ever spin tires on the road. Its the rate of force applied that causes slippage. Your saying any more than 1650 ft lbs of torque will spin the tires, but in the previous sentance you say 400 ft lbs of torque @ 6HP will spin the tires??! I am no genius but I know enough to know that 400 is alot less than 1650. Though... I would be absolutely impressed if any vehicle can create 1650 ft lbs of torque off the line.

 

[LaserRST]

Originally posted by DSMJim


Now try and teach the HP vs. Torque think to a bunch of Honda guys. Good friggin luck....
They honestly think that HP at really high RPM is the best way to have it. I tell them a flat power curve that start low and stays constant is way better than one that just peeks at 9000rpm and they look at me like I have 3 heads.

... Hondas are all high revving engines... forgive them... they dont know any better.

 

[nine5raptor]

1650 at the halfshaft is much more different than the 400 you stated at the flywheel (gear ratios). I can make 400 ft. lbs at the wheel with a breaker bar. that won't spin the tires but 400 at the crank will. 400 ft lbs at the crank at 2000 rpm = 152 horse. more than many hondas that can spin the tires easy.

I have done burnouts in flatbed tow trucks. not a semi true, but with a max rpm of 4000, hp still sux.

horsepower has nothing to do the beginning of spinning a tire, only the keeping it spinning.
when a tire starts to slip, motion is just impending (take any statics class) torque is all that matters. horsepower is a function of time while friction is not. static friction and torque are both time-independent variables.

 

[Enigma_Man]

I seriously reccomend www.howstuffworks.com for some really great, easy to understand, and comprehensive explanations of torque, horsepower, force, grip, and anything you'd want to know about your car, the parts, and forces involved.

Read up

-Jesse

 

[Wikkedson]

Originally posted by DSMJim


They honestly think that HP at really high RPM is the best way to have it. I tell them a flat power curve that start low and stays constant is way better than one that just peeks at 9000rpm and they look at me like I have 3 heads.

Its more about high RPM torque for drag racing. If you could make 500ft/lbs at 9000rpms in a honda then it would haul ass. If it was about high RPM horsepower then every car would be fast.

In turbo cars, Peak torque varys depending on the turbo. If you look at a dyno sheet of a t25 powered car, usually peak torque will come in around 2900-3200 rpm, then drop off the entire time. While Horsepower will increase the entire time until around 6000rpm.
So the chart will pretty much look like a big X.

You can even feel this in your car, when the turbo spools, the car pushes u back hard, then kinda dies off at high rpm. Or atleast on a t25 car. That is because TORQUE, is what you feel.

 

[LaserRST]

Originally posted by nine5raptor
1650 at the halfshaft is much more different than the 400 you stated at the flywheel (gear ratios). I can make 400 ft. lbs at the wheel with a breaker bar. that won't spin the tires but 400 at the crank will. 400 ft lbs at the crank at 2000 rpm = 152 horse. more than many hondas that can spin the tires easy.

I have done burnouts in flatbed tow trucks. not a semi true, but with a max rpm of 4000, hp still sux.

horsepower has nothing to do the beginning of spinning a tire, only the keeping it spinning.
when a tire starts to slip, motion is just impending (take any statics class) torque is all that matters. horsepower is a function of time while friction is not. static friction and torque are both time-independent variables.

Right torque is not a function of time which is why it is not the reason for tire spin. Static friction has nothing to do whith tire spin. Kinetic friction does. Torque is rotational force it doesnt matter how fast its going, for instance a water wheel like they had in the old days may rotate some 12 times per minuite and have 3600 ft lbs of torque. You some how put this contraption in our cars with the same gear ratios... I guarantee those tires are not going to start burning out, but there is still a tremendous amount of torque. What causes wheel spin? It is the rate at which the torque is applied... back to the ol HP formula...

HP = torque*RPM/5252

Where RPM is the issue for most people when they lose traction. If you can launch at a normal RPM and have enough torque to get you moving off the line, limiting your HP you will have a smooth transistion. When you need to up the RPM to find the right amount of torque... HP will jump up too. It right there in the equation. Its all about the torque over HP in the bottom end... its a Big Block trick which is really hard to replicate in small displacement engines. Especially turbo cars since their VE wont get anywhere near 100%. There are ways to get it though and Displacement is one of them.

 

[autronicDSM]

Originally posted by LaserRST


Uh I would like to believe that.... but I have never seen a 300 hp Diesel with 800ft lbs of torque ever spin tires on the road.

i might be wrong but i think i'm not...power to weight ratio makes a difference. i assume you're talking about truck or a semi. those are a lot heavier and force (weight of the car) pushing down on tires. i see it as traction. those engines rev low and have different gear ratios compared to sport car to haul stuff. just my $0.02

 

[2-0turbo]

Please, everyone read this . Bruce does an excellent job of explaining the difference between torque and HP.

 

[mike9146]

"Please, everyone read this . (Link to great torque/HP article) Bruce does an excellent job of explaining the difference between torque and HP."

And whadda know, now we're back to where we started. A link to one of the sites contained within the search results of the link I posted when this whole discussion started! How could I have possibly anticipated that this discussion would turn out this way?



Mike C.

 

[2-0turbo]

Originally posted by mike9146

And whadda know, now we're back to where we started. A link to one of the sites contained within the search results of the link I posted when this whole discussion started! How could I have possibly anticipated that this discussion would turn out this way?

Oops. I didn't follow the original link you posted. I wasn't even going to get involved in this discussion. I mean, the question was "How to add torque" or something like that. It snowballed into most people being quite confused about the difference between torque and HP--hence the post. Oh well.

I don't really know the answer to the question. Lotsa' boost at low RPM's is my suggestion. How to do that without compressor surge, is a mystery to me.

 

[nine5raptor]

"Right torque is not a function of time which is why it is not the reason for tire spin. Static friction has nothing to do whith tire spin. Kinetic friction does. Torque is rotational force it doesnt matter how fast its going, for instance a water wheel like they had in the old days may rotate some 12 times per minuite and have 3600 ft lbs of torque. You some how put this contraption in our cars with the same gear ratios... I guarantee those tires are not going to start burning out, but there is still a tremendous amount of torque. What causes wheel spin? It is the rate at which the torque is applied... back to the ol HP formula...

HP = torque*RPM/5252

Where RPM is the issue for most people when they lose traction. If you can launch at a normal RPM and have enough torque to get you moving off the line, limiting your HP you will have a smooth transistion. When you need to up the RPM to find the right amount of torque... HP will jump up too. It right there in the equation. Its all about the torque over HP in the bottom end... its a Big Block trick which is really hard to replicate in small displacement engines. Especially turbo cars since their VE wont get anywhere near 100%. There are ways to get it though and Displacement is one of them."

I'm enjoying this discussion...

You say that torque and static friction don't matter once you are moving, but when you are driving down the road static friction is all of the force your tires exert to keep you on the road. Only if the brakes are locked or the tire are ALREADY spinning does kinetic friction come into play. The are determine by the sliding of the two surfaces. If you are rolling, you are not slipping and static friction what you are concerned with. And the rate torque is applied? the torque is applied at a constantly increasing force until that instant when the wheels let loose. then, you can talk about the rate max torque can be applied and the kinetic friction which translates into how well you keep the tires spinning.

the comment I made about the gear ratios was because the torque you make at the fly is not the same as at the wheels. dyno runs are made in the gear closest to 1:1 to get a close, albeit inaccurate tq measurement.

 

[LaserRST]

2-0turbo:

"I don't really know the answer to the question. Lotsa' boost at low RPM's is my suggestion. How to do that without compressor surge, is a mystery to me."

To increase your bottom end torque is really tricky for small displacement cars. If you want to use your turbo in the application, then a stutterbox will do good but you will still not achieve the torque over HP curve. Big Block racers use sheer displacement and crank angles to find good torque. If we could stroke our engines that would be a pretty sweet start. What people have done in the past is use higher compression ratios to help off the line drag runs. This is why Mitsubishi incorporated the higher comp pistons in their 2gs. They notice people like the pull of the vehicle so they adjusted their cars with higher CR pistons, a smaller quicker spooling turbo, and longer thinner intake runners. Unfortunately this comprimised the top end HP, but the company was looking for something that sells off the lot more so than an all out exotic sports car. To increase bottom end torque for our cars we need to some how apply some NA tricks to our cars with out sacrificing turbo size, and top end CFM. I am definately gonna leave this open for discussion cuz I would love to hear any ideas. The one that I noticed, not only in the DSM family but in other newer cars as well is the Dual runner intake or VGI, like the JDM Cyclone. Boring out the engine will help, and progressive shots of nitrous is something I have been kicking around for a month now, but havent got around to exactly how much would be needed or how to control something like that... too much for me since I already have trouble affording a plain kit already.

 

[Stock90GSXT]

I would love to know tips on how to increase bottom end torque. What alot of people including me done on small block engines is destroke the engine. Shorter stroke, longer rod. It will increase bottom end torque, but that in turn deals with a custom crank. Whats nice about the automatic cars is that they can put a higher stall converter in the tranny to get the turbo to start spooling on the launch at around 3500-4000 RPM. I think the stall speed for a auto dsm is around 2-3000.

 

[GSTwkd]

Great info guys . Learning more everyday. All I know is on my dynos I've gotten 343wtq @ 4100rpms which seems to be right where I start to melt my tires in 1st 2nd and 3rd(sometimes). Now I only peak 303whp @ 5800rpms and I'm not really sure where that leaves me as in hp/tq ratio wise. So I have to believe that torque plays a big factor when it comes to wheel spin. I thought I heard somewhere that sometimes by adding fuel you can gain some tq but might lose a few hp as a result. Ahh, the fine line in tuning.

 

[autronicDSM]

that could be true. by adding more fuel you create more pressure in cylinder when it ignites. it will push the piston down with greater force, that gives you more tq.

my car runs pretty rich (11.0:1 off boost, 10.0:1 under boost) and i'm running 30 degrees of timing across the board before i hit the boost (i got stand alone) and it pulls pretty hard. once i fix my little problem of blowing head gaskets i'll dyno the car to see how much it makes. right now i got big 16g on there and i question if i need a bigger turbo. i really like how hard it pulls right now