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Justin_cv87
03-15-03, 01:45 PM
Both torque and HP is important for speed right? well i was playing Gran Turismo 3 for the PS2, and it has the title of "Realistic Driving Experence" because it's so real. they calculate everything down to the last digit. Well in the game i bought a Grand Sport, and got it up to around 450 hp by upgrading the exaust, tires, and racing chips and stuff like that, but the torque dropped to 50! the speed was alot faster though. I guess what im wondering is does this happen in real life? if you double a cars HP with mods will it's torque drop alot? and if it does drop why is it really needed if you have alot of HP?

Thanks in advance!

Geof180
03-15-03, 02:12 PM
hey justin..... i have noticed that as well.... i think it is a fluke in the game, that's all.....

you calculate horsepower from torque... you can easily measure the twisting force produced by the engine in an automobile...

this value, along with its RPM, is how you can find the horsepower....

in GT3, it will tell you at what engine speed the max torque is produced... multiply these numbers together and then divide that amount by 5252... (if you would like, we can go over the derivation of the 5252 later on :cool)

does this help big man??

Geof

Justin_cv87
03-30-03, 04:15 PM
yeah, it helped, for a while i thought everything i learned about torque (which isnt much :L) was wrong. i dont get the 5252 thing tho :(

echoecho11
04-21-03, 10:24 PM
Justin the confusion is intirely justifiable. ask ten people this question and you get ten ansers some good debate and then total confusion. HP is the time it takes to lift x amount of weight x high. not shore how much weight or how high but HP is a funksion of time. torque is the twisting forse ( or mybe the forse it whoud take to apose) caused buy a spining object. it is measerd in foot pounds. a transmittion or the third member in your car traids HP for torque. a gear set could be set up to do jest the oppiset. now take your ten speed bicile ( you do have a ten speed don't you ?) you are going along in top gear, you are peddeling at a consistance speed ( RPM) and consistance aplyed presser on the peddels( HP..AH..people power) at a cosistance speed ( distance in time= speed) ok now we come to a hill and you relise that you need more power to get over the hill. so you shift the bike down a gear. asumming that you pump the peddels at the same speed(rpm) then the bike whould go slower but you whould have more power ( twisting force....torque) to go over the hill. HP has been used a selling tool for cars but in this contexed it is very deseptive at best. all 300HP engines don't have the same amount of torque. torque is what moves your car and what you fill as it acelerates. 65HP with the right gears( traiding HP for Tq. ) will snap your neck......is this not what bullet bikes are all about? so TQ snaps your neck and HP is how fast it snaps your neck . TQ= power or force HP = speed or how fast


hope this helps Justin :bu

spelling was not coverd in mecanics school thank god:hb

reubenmc
04-21-03, 10:59 PM
Echo, I don't know if that helps Justin, but that deffiently helped me have more of an understanding of torque and horse power. Thanks for that post:)

Edmond
04-23-03, 02:20 PM
Originally posted by echoecho11
HP is the time it takes to lift x amount of weight x high.

I remember that you could actually measure the HP of your human body. They did something where they timed how fast you ran up a flight of stairs. It took one helluva athlete to achieve 1 HP!

Utah
04-23-03, 05:18 PM
So if you want to increase acceleration, would torque be more of what you want to increase??

Edmond
04-23-03, 05:31 PM
Originally posted by Utah
So if you want to increase acceleration, would torque be more of what you want to increase??

Yes. Our L98's definitely have a lot of torque, but the HP has a lot to be desired. That's why they run out of breath at the top end while the LT1-current motors are still pulling strong.

echoecho11
04-23-03, 10:26 PM
Originally posted by Edmond
I remember that you could actually measure the HP of your human body. They did something where they timed how fast you ran up a flight of stairs. It took one helluva athlete to achieve 1 HP!

Edmond It would not make a perttey sight to hook a rope from a norht bound horse to south bound human. even swortzneger.

but the horse power story even gets deeper? a gasoline hp = only 60% of a electric hp. diesel hp is much higher... most of the big semi trucks are rated around 350 hp and are terbo charged and blowen ( as in twin terbos and a blower ). so all hp's are not equail. :bu

echoecho11
04-23-03, 10:59 PM
Originally posted by Utah
So if you want to increase acceleration, would torque be more of what you want to increase??

UTAH First off I like that blue vette . Increaseing torque would defently make your car accelerate faster,however it is far from the only way. weight to power ratio is another. your vette is faster with only one person in it than it is with two. lettes look at the example of the bullet bike. It has less than a fifth of the power your vette has , but your vettes wight is around 3300 lp, the bullet bike is about 350 or one tenth the weigh of your vette. the bike will accelerate faster. :Steer

Geof180
04-23-03, 11:17 PM
1 HP = the force needed to lift 33000 pounds 1 foot in 1 minute...

measure of an engine's ability to perform work

yes...what echoecho11 said... ;)

Geof

Edmond
04-24-03, 08:05 PM
So how do you build a car for more torque as opposed to more HP?

What I usually see in the ads are HP increases. Torque seems to have taken a backseat to HP.

LEEJANDZ
04-24-03, 08:39 PM
Originally posted by Edmond
So how do you build a car for more torque as opposed to more HP?

What I usually see in the ads are HP increases. Torque seems to have taken a backseat to HP.

You need to focus on the bolt on's that increase the torque curve.
Typically the bigger the CID the more torque an engine produces.
But you have the trade off... a big CID wont rev as high.

example:
A 400 CID will have more torque but a smaller powerband than a 350.
Most people compromise and stroke their 350's to 383.
Pretty happy balance.

They make cams & intake manifolds designed for torque.
If you go with a smaller inch diameter exhaust it will prdocue more torque.
2' vs 3'

;)

JASON *** BRAND NEW MAGNECOR WIRES FOR SALE!!! (http://www.leejandz.com/mag-corvette.html) *** 1979 L-82

echoecho11
04-29-03, 03:08 AM
Originally posted by Edmond
So how do you build a car for more torque as opposed to more HP?

What I usually see in the ads are HP increases. Torque seems to have taken a backseat to HP.

" EDMOND" sorry for not ansering your thred sooner but you have two questions that I think are deserving of some good thought. These are great questions Edmond. letts look at the second question first because it will help to anser the first. I have also noticed that adds tend to use HP a selling point much more than TQ. It would be real hard to build a part like headders or a manifold that would add say 30 HP ( or 15% HP increase) to any engine that you put it on. thats not relistic because they don't know what condition or what state of tune that every engine that ther parts might be put on is in. but they can ball park it as to give us some indication as to what we should expect. it is a buyer beware deal at best. I have put some of these parts on cars and lost power. some of them made the car run dam fast but the car only had two speeds, all the way on or off. no inbetween, if you are going to get grub in a snow storm cars like this loose there charm real fast. during the mussel car or big block area it was all about TQ. lettes take the lightest striped down car and put the bigest ( meaning the most cubic inches)motor in it. the fore an a quorter horse (425 hp) was empressive but it was the 580 or so foot pounds of TQ that was getting the job done. I remember a artical that ran in hot rod were they took a 4600 pound caddy with a 472 CI motor in it and they whould take wight off it then run it through the 1/4 mile to see what efect that it whould have. they striped the interior and ran it ,cut the top off and removed the doors and ran it , took the front fenders off along with the hood and even torched all the sheet meateal off the back. when they got done about all that was left was the engine, drive train, frame. front/rear sup. and a seat. this car only cost them about $800 and the motor was stock and they had it running in the high tens. Ok this car had a fue more compremises than we whould like to live with but it demenstratees what lots of torque wiil do in a light car ( think the caddy was rated at 390 HP). so this should give you some idea what the big buzz is about big block vettes of the late sixtys and early seventys is all about. they was rated at 375 to 460 HP but read their TQ ratings and you will see that some of them had doubbel what most small blocks had. in the mid eightys,ninetys and the new melleniam because of polution and deminishing fuel the feds have mandated that auto makers find a better way to get the job done. they did but thets another thred and this one is gettig a littel long so I better let it end. If I havent bored eveyone resopnd to this thred and let me know. I have lots of ideas how to add TQ to that 88 TPI L98 vette.
:bar

BMBT= big mouth bench taulker

:L

Rob
05-12-03, 06:42 AM
Justin,

You may want to read this article:

http://corvetteactioncenter.com/tech/hp_torque.html