More Torque than Hp?

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hux340

hux340

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Hi All,
As above states what's a small block ie. 340 drive like when it's got more torque than hp. They reckon hp sells cars, but torque wins races. I love torquey motors.
I'm looking at giving my motor some performance upgrades. Key thing is I don't want a high revving hsp motor. I usually don't rev past 5000rpm. I remember reading the stories on the I think 1970 Buick GS Stage 1's with 510ft/lb torque & 375 hp. I know this was under rated & a big block motor. Is this a good thing.
 
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Hp and Torque aren't two separate types of power. Hp is the combined effort of Torque and RPM. Think of Torque as a snapshot of a single powerstroke and HP is all the Torque snapshots over time (RPM).

N/A Torque is basically displacement and VE.

5000 rpm gives you a decent powerband.
Something like xe262h cam, headers, rpm intake 650 carb decent heads like EQ.
 
Don't forget compression. As much as you, and your fuel, can stand.
 
hux340 said:
Hi All,
As above states what's a small block ie. 340 drive like when it's got more torque than hsp. They reckon hsp sells cars, but torque wins races. I love torquey motors.
I'm looking at giving my motor some performance upgrades. Key thing is I don't want a high revving hsp motor. I usually don't rev past 5000rpm. I remember reading the stories on the I think 1970 Buick GS Stage 1's with 510ft/lb torque & 375 hp. I know this was under rated & a big block motor. Is this a good thing.
Click to expand...

well... lets put it this way. My built 99 cummins powered 2500, 4x4, 5 speed manual dyno tested at 467hp @ 2200 rpm BUT the torque was 1257 ft lbs @ 1800........ to the rear tires. Truck weighed 7600 lbs(i had SUPER heavy bumpers made of 1/4 inch steel), ran a 14.2 sec, 95 mph 1/4 mile at Indy Raceway park back in 2008 and consistently drug 30,000# sleds to 280-290 feet (300 is a full pull). Probably could have dipped into the 13s if it'd had a better driver. Driving a torquey motor was fine, just had to watch take offs on wet/icy roads.
 
What's it like to have power under your foot all the time and not have to wind the engine up to get it? Umm... pretty self explanatory. Perfect for the street. Still fun at the strip. Mine makes 314/550 at the wheels and runs 11.70's.
 
I love the torque of 7.5 psi boost from a twin screw blower! Figure about a 60 percent boost in torque at that boost. Or, you could cam it to pull hard to 5500, and not hurt the bottom end torque much and make a fair amount more power. (10 percent up top?)
 
Hux, a mild cam with the basic bolt on parts will do the trick.
A lot of torque? That is normally found with a longer stroke crank. And my opinion for that would be an echo of the often heard 4 inch arm.

A very well thought out cam can provide an excellent high torque response.
 
hux340 said:
Hi All,
As above states what's a small block ie. 340 drive like when it's got more torque than hsp. They reckon hsp sells cars, but torque wins races. I love torquey motors.
I'm looking at giving my motor some performance upgrades. Key thing is I don't want a high revving hsp motor. I usually don't rev past 5000rpm. I remember reading the stories on the I think 1970 Buick GS Stage 1's with 510ft/lb torque & 375 hp. I know this was under rated & a big block motor. Is this a good thing.
Click to expand...


My favorite part of having more torque than horsepower is beating stock tired Hellcats and everything but a Nissan GTR with slicks and a pumped V10 Viper at the drags.

I recently had the car chassis dynoed and was surprised when it spun out 382HP at 4600 rpm and 525 ft lbs of torque at 3541 rpm. This is at the rear wheels.

I have a bit more tuning to do on my '70 before I get some time on the chassis dyno to verify my A/F ratios and power outputs.

JohnRace2 (Large).jpg
 
If torque wins races all the Comp Elininator and Pro Stock guys are doing it wrong.

Horsepower IS king. To dispute this is stupid.


^^^^^These are the famous words of Chris Alston^^^. Since horsepower is work over time, the quicker you do the work, the lower your ET.


Simple really.
 
Alston was talking about race cars. Not disputing the statement, just adding perspective...
 
(RPM * T) / 5252=HP

RPM is the engine speed, T is the torque, and 5,252 is radians per second

HP is a function of torque


Which is more important? Depends on the intended function of the vehicle. I certainly don't want more HP than torque in my truck. My motorcycle, it's ok there. My dart, I like the torque. etc.
 
moper said:
Alston was talking about race cars. Not disputing the statement, just adding perspective...
Click to expand...


I realize that. I also have been around long enough to know most guys are more impressed by being able to drive 10 MPH in high gear and fog the tires. I'm not impressed by that.

The fact still remains that in the end of all bullshit, torque does very little of the actual work to move the car without a bunch of help.

If any doubt that, use a direct drive gear box and. 1:1 rear axle ratio. Use a clutch so you don't have any torque multiplication from that. You'll just have engine torque to move the car.


It will be a pig. It won't accelerate.
 
I dont understand why this keeps on being misunderstood. Torque and Hp aren't two separate things that have different abilities to get your car down the road. There basically one in the same. Hp is the combined ability of torque and rpm. Torque and rpm is what moves and accelerate your vehicle from the first moment of movement to the top speed and the rate of acceleration and everything in between.

Torque and rpm combined are the power your engines has. Your engine can't do one without the other. Try measure how much torque your engine has with it off (no rpm).

You can just times torque and rpm together and still get the power curve. Just the numbers will be a bit meaningless. In the millions. The reason they use the constant of 5252 in the equation was so we could compare them to the horses we were replacing at the time. Now days watts would make more sense.

Another way to know torque in itself doesn't tell you everything is take our standard way of comparing performance the quarter mile.
Not one of you can tell me how much torque i need to go 12's with a 3300 lbs car. But you all could figure out the hp.

Probably something like 350 hp. Now theres many ways to make it from 920 lbs-ft @ 2000 rpm to 115 lbs-ft @ 16,000 rpm and everywhere in between. All will get the job done with very different gearing.

Why doesn't torque alone tell the performance ability of the engine.
Image two guys moving patio stones. One guy is bigger and stronger than the other but the other is faster. So the bigger guy can move two stones at once but the smaller guy do it twice as fast so the both with finish the job at the same time.

So an engine A that make 500 lbs-ft at 5000 rpm has the same ability as an engine B the makes 250 lbs-ft at 10,000 rpm. So engine A does more work per revolution but B does the same work in 2 revolutions but in the same amount of time which is the power.

Plus when we talk about torque engines what we are really saying is engines that make hp at low rpm.
 
Power is great but useless without a transmission and chassis to handle it, get it where it belongs, and stop.
 
Another visualization that may help some is pushing a car. How hard you have to push your foot down on the first push...that is the torque required to do the job. The subsequent pushes get easier. As you keep going it gets easier, and the pushes come faster. That's horsepower. When you can't push any faster you need bigger lungs (cam and heads).

Torque is a function of effective displacement. There's no such thing as building an engine for torque. The only way to increase low rpm horsepower is to increase effective displacement.

Torque does nothing to accelerate a vehicle. It resists slowing down. The diesel pickups from the 80's are a great example. High torque, low hp. They can pull a train up a mountain, but can not accelerate the load. I've never heard anybody say those things were fun to drive. You build for hp at the rpm you want.
 
273 said:
I dont understand why this keeps on being misunderstood. Torque and Hp aren't two separate things that have different abilities to get your car down the road. There basically one in the same. Hp is the combined ability of torque and rpm. Torque and rpm is what moves and accelerate your vehicle from the first moment of movement to the top speed and the rate of acceleration and everything in between.

Torque and rpm combined are the power your engines has. Your engine can't do one without the other. Try measure how much torque your engine has with it off (no rpm).

You can just times torque and rpm together and still get the power curve. Just the numbers will be a bit meaningless. In the millions. The reason they use the constant of 5252 in the equation was so we could compare them to the horses we were replacing at the time. Now days watts would make more sense.

Another way to know torque in itself doesn't tell you everything is take our standard way of comparing performance the quarter mile.
Not one of you can tell me how much torque i need to go 12's with a 3300 lbs car. But you all could figure out the hp.

Probably something like 350 hp. Now theres many ways to make it from 920 lbs-ft @ 2000 rpm to 115 lbs-ft @ 16,000 rpm and everywhere in between. All will get the job done with very different gearing.

Why doesn't torque alone tell the performance ability of the engine.
Image two guys moving patio stones. One guy is bigger and stronger than the other but the other is faster. So the bigger guy can move two stones at once but the smaller guy do it twice as fast so the both with finish the job at the same time.

So an engine A that make 500 lbs-ft at 5000 rpm has the same ability as an engine B the makes 250 lbs-ft at 10,000 rpm. So engine A does more work per revolution but B does the same work in 2 revolutions but in the same amount of time which is the power.

Plus when we talk about torque engines what we are really saying is engines that make hp at low rpm.
Click to expand...



They are not seperate but they are two different things. As in the diesel example above.
 
It's the same old stupid argument. I even see it here in our shop. I start talking about horsepower and my son will say, "Yeah, but torque, blah, blah, blah" .............OH CRAP!!!!!
 
I don't get why we have to keep arguing this TQ vs HP every time it comes up.
These are just two sides of the same penny. One side has a picture of Ruler on it, and the back has a picture of his house.The Ruler owns the house. The house is bigger than the Ruler, covers the Ruler. and welcomes in the new Ruler after the first one is done. If you burn down the house, the Ruler has no place to stay. If you shoot the Ruler, the house is empty. One is useless without the other.
It's all about perception. We like BBs cuz they have more inherent torque at low rpm. Sure you can build a SBM to come close to it, But then it has no power at high rpm. You can build the BB for high rpm power, and it's low-rpm torque will still embarass most SBMs. Mostly we are referring to the curves on the graph. And so it is perfectly natural to refer to one or the other.
I mean who says I have 114 hp at 2000 rpm; nobody I know! We say I have 300 ftlbs at 2000. Why? Well, because it's BIGGER. that's perception. And nobody I know says I have 350ftlbs at 6000 rpm. No we say I have 400horsepower at 6000. It's BIGGER!
We all know what they are and how they are related, and how to use the numbers. I for one don't need an education every time.
 
To have decent low-speed performance with a 340;
and to make a torquey engine,lol, you need to trap the maximum amount of combustible mixture, as early as possible, compress the chit out of it, burn it all up,transfer the energy to the crank for as long as you dare, get rid of it as fast as you can, and then bring in the next charge. Pretty simple really.
Or just get more gears; either in the back or in the trans; it makes no difference. TM ( Torque Multiplication) is King on the street.

I once put a complete 318 top end, cam and all, onto/into a 340. Man that thing was fun,in a 65 V-100 station wagon. That was about 1974. I used Hooker Fenderwells and straight pipes to shorty thrushes and still straight to the back.
That's trapping, compressing, holding for as long as you dare, and then getting rid of it as quickly as possible.
Now, I'm not suggesting you do that; I was a broke-azz kid, and these were what I had accumulated.
Good recipes have already been presented.
 
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It's good to have a lotta torque at the torque peak, and a lotta horsepower at the power-peak. Cuz by the power peak, the torque is fast shrinking.
It's nice to have the torque peak at an MPH where it does some good. And
it's nice to have the power-peak timed right.
And it's really nice to have them both matched to your transmission, cuz it really hurts when you shift, and both torque and the horsepower went on vacation just then..
 
Heres a kind of a formula the OP can play with to narrow down what he wants. Its based on that engines make a narrow range of lbs-ft per cid.

Most mid level engines make around 1.15 - 1.25 lbs-ft so say average of 1.2 lbs-ft @ peak torque and at peak hp make about 90% of peak torque. And peak torque and hp are about 1500 rpm apart. Play with different cid at different hp peak rpm with the hp formula. You can do pretty good guesstimates.
 
Roots blower. Buddy just made 1258 lb/ft of torque at the rear wheels on this street car. It runs 8.40's
 
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