Chasis dyno this, chasis dyno that. The only way to settle it is to pull the engine, and put on an engine dyno, such as a waterbrake, or edy current dyno. Chasis dyno s are just good for comparisons, not real numbers. You can say my truck made xxx , and your truck made yyy, so mine is more powerful, but you cant compare that number directly. Even in an engine test cell different dyno operators can get different HP readings, on different tests. therefore if people are trying to compare dyno readings from one dyno to another that information is very skewed. Thre are differences in the physics of there actual dynos, that make some more accurate, but the numbers are just a guide.
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Competition Ever see a 1000hp truck spooling up?
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fbaurley said:
My dynos are eddy current absorber dynos. We're measuring the HP at the wheel, arguably the only HP that really matters. What you make at the engine is good for bragging rights, but how much is lost in the drivetrain and tire/pavement interface is just as important. We're in the business of selling diagnostic and tuning tools. We make it easy for people to develop their vehicle into something faster, more powerful, more efficient. We're not trying to say we can make the biggest HP numbers, that's kinda silly. We give realistic, accurate, repeatable results. Agreed, there are a lot of variables that are not always correctly dealt with that makes test results vary a bit from dyno to dyno. However, if the dyno is used correctly, most all dynos will give very similar test results regardless of who built them. The key is in whoever is operating the dyno and how he/she ensures that everything is done correctly.
jetenginedoctor said:
Good!! Thats just what we need.
Now where were those tq numbers I asked for? Or doesn't your dyno measure torque?
jwilliams3 said:
I got to the bottom of this, and you are indeed telling the truth.
What happened was the owner of the truck was confident that his transmission WOULD NOT downshift during the test. So, thinking there was no danger of a VERY violent downshift from 3rd gear, they began the test loading the engine by holding the rollers at a fixed speed, and rolling into fuel to build EGT and boost. As this was happening, the transmission decided to take the path of least resistance by downshifting. . . . . into first gear. In first gear, there is enough tractive effort to very effectively stretch the tiedown straps enough that the tires managed to crawl over the rollers, contact the front part of the dyno, and try to flip it up under the truck bed behind the wheels. Big-time excitement, no doubt.
I didn't verify with the dyno operator if the tire pressure was correct or not, but in the end, it was a result of the incorrect assumption that the trans wouldn't downshift. It did. Scary things happened, nobody got hurt.
If this would have happened on another dyno, it likely wouldn't have been able to make enough traction to get over the roller, but that's another discussion altogether. Thanks for telling me enough that I could find out what happened. You're not such a bad guy after all. . . . heh. . . .
Sled Puller said:
Sure it does. It requires that I attach the tach probe, though. Those results were taken from our TDR roundup a couple weeks back at Kerrville, TX. I was doing low-buck promotional fun tests, and trying to get everyone that wanted to test on and off the dyno to keep everyone happy. Setting up the tach probe on every truck that rolled across would have added another 15-20 minutes to each test, better than doubling the time each one takes. It doesn't make sense to go to that much trouble, does it?
If these were normal priced $85 tests, you can be sure you'd get the TQ numbers. But honestly, what difference does it make? Torque is not HP. HP is what makes things happen. You can have 1000lb/ft of torque on something that doesn't go anywhere. If nothing is moving, no work is being done, hence nothing to brag about. Give me a long enough lever, and I'll make 1000lb/ft of torque with one hand. Big deal! It's HP that's hard to get out of these engines, not torque.
Okay, then I know exactly whose it is. I'm kinda curious as to what exactly happened, though.
I'm not calling you a liar, and I'm not trying to be inflamitory. I'm here trying to help people out, not engage in Mortal Kombat in a flame fest. It's important to me that we be as factual as possible. If what I suspect happened is indeed the case, it's a failure of not only the dyno operator but also possibly the vehicle owner. When I test vehicles, I specifically ask how much power they estimate that it'll make. It's not so I can manipulate the test results, it's so I know how I need to restrain the vehicle to ensure that it makes full traction and 100% horsepower. The safety aspect of it is obviously of primary concern, as I don't want anyone or anything hurt as a result of our testing. A truck that makes 200 hp (or less. . . . mine for example ) will not be tied down the same way a truck expected to make 500hp or more will be. Whether it's an auto or manual trans comes into play as well, as well as if the guy pushing the accelerator pedal (not always the dyno operator) knows how to make the test correctly and safely. Guys who try to bounce the load cell are endangering everyone, including themselves and their truck.
Anyway, it looks like you might have misunderstood what I was calling phooey on. THere's no doubt in my mind that there are some 1000+hp trucks out there on the street. My entire stake in all this is whether or not we can test them or not. And we can. No problem.
I'm not calling you a liar, and I'm not trying to be inflamitory. I'm here trying to help people out, not engage in Mortal Kombat in a flame fest. It's important to me that we be as factual as possible. If what I suspect happened is indeed the case, it's a failure of not only the dyno operator but also possibly the vehicle owner. When I test vehicles, I specifically ask how much power they estimate that it'll make. It's not so I can manipulate the test results, it's so I know how I need to restrain the vehicle to ensure that it makes full traction and 100% horsepower. The safety aspect of it is obviously of primary concern, as I don't want anyone or anything hurt as a result of our testing. A truck that makes 200 hp (or less. . . . mine for example
) will not be tied down the same way a truck expected to make 500hp or more will be. Whether it's an auto or manual trans comes into play as well, as well as if the guy pushing the accelerator pedal (not always the dyno operator) knows how to make the test correctly and safely. Guys who try to bounce the load cell are endangering everyone, including themselves and their truck. Anyway, it looks like you might have misunderstood what I was calling phooey on. THere's no doubt in my mind that there are some 1000+hp trucks out there on the street. My entire stake in all this is whether or not we can test them or not. And we can. No problem.
i was thier the dyno operator didnt even ask if about the transmission. He claimed he thought it was a stock truck. (a stock truck with ats, edge and quad stickers all over it, A copilot and an ez in the cab, two stacks with ladder and weight bars) :--)
It is an auto they do what they want to do. Every other dyno i have been on has never had an issue with downshifts. Plus it is a allsion 5spd When dynoing it should be in 4th, when it downshifts from 4th it goes to third, Not First. The Strapping system was the weakest excuse of a system i have ever seen. And it was a very poor positioning of the dyno by the operator. It was placed to wear the trucks front ends where downhill of the rest of the truck (not including the dyno height) aproximatly 6" below the base level of the dyno.
Travis
It is an auto they do what they want to do. Every other dyno i have been on has never had an issue with downshifts. Plus it is a allsion 5spd When dynoing it should be in 4th, when it downshifts from 4th it goes to third, Not First. The Strapping system was the weakest excuse of a system i have ever seen. And it was a very poor positioning of the dyno by the operator. It was placed to wear the trucks front ends where downhill of the rest of the truck (not including the dyno height) aproximatly 6" below the base level of the dyno.
Travis
jetenginedoctor said:
JED has admitted he is new to this Diesel thing, so I will give him a chance to rethink TQ, for a future thread.
Last edited:
Jet,
Why did you buy a Cummins if torque is "nothing to brag about"?
Why did you buy a Cummins if torque is "nothing to brag about"?
I'm with Gene, Justin AND THE REST OF THE TDR...
I can't believe what I'm reading. If ever there was a perfect case of someone biting the hand that feeds them... this is it.
Matt
I can't believe what I'm reading. If ever there was a perfect case of someone biting the hand that feeds them... this is it.
Matt
I'm gonna don my flame suit and side with JED.
TDR has turned off a lot of folks with the know-it-all attitude of some members (I'm as guilty as anyone at times, though I'm much less qualified).
There are a lot of lone-wolf bombers who are making big HP, and did it without a TDR membership.
I guess I see a lot of myself in JED. I also think that East vs West is childish BS.
Sleddy-- TQ is important, yes, but EVERYTHING that JED said is true. You CAN build 1000lb-ft with a long lever. How much work is going to be done? Not much, unless you can run really fast.
TQ is important because it tells you how much work you could theoretically do. Like, it will tell you if you can pull only a 2K# tagalong vs a 40K# sled.
But HP is even more important because it adds the element of time. THIS is significant because HP allows you to trade rpm for torque with gear reduction. THIS is why the 345hp Hemi will often tow as well as a stock CTD.
If you wanted to, you could pull a Class 8 trailer with a 900hp formula 1 engine spinning 16K rpm. Would it last long? Maybe not. Maybe so, though. The actual load on the engine after the quadruple-or-more gear reduction is probably very little.
Now, where your engine make its power will determine how well it does certain things. But we also can't separate the engine from its packaging. We won't take a high-revving motorcycle engine and drop it in a Dodge, and we aren't revving a CTD to 13K rpm.
A pulling engine doesn't need to make much low end power at all. If it did, you wouldn't see the huge, unstreetable turbo(s) they use. All a good pulling engine needs to do is make good power (torque) while the RPM is bouncing off the governor. So if your turbos don't spool till 2500 rpm, no one cares.
A drag engine must have good power from launch. This is why we have higher stall converters to allow the engine to spin up to where it makes more power (torque). Drag racers will always tell you that they try to match a converter's stall speed to the tq peak of the engine.
A street engine needs quick spoolup and a broad, usable powerband.
A dyno engine (dyno in this case being 248c) is also built differently. A dyno engine just has to have a good, fast torque rise to get the roller spinning. The farther and faster this tq rise happens, and the higher the rpm can be sustained, then the more "power" it will make.
In each case, the more you optimize an engine for a certain application (street, race, pull, dyno), the more specialized and inflexible it becomes.
At a constant RPM, torque IS power, and hp is torque. The rpm just determines the ratio (because of the time element).
The beauty of the Dyno Dynamics dyno is that it can vary any combination of parameters to keep any other combination of parameters constant. If you want to test EGT at constant rpm as load is applied, you can do that. You want to see how fast your truck moves a 3K# load vs a 15Klb load-- you can do that. You want to see the correlation of boost to RPM as load is varied or rpm is varied, you can do that.
With a Dynojet, you have to change the drum to change the load. A fast torque rise with a light drum can "spike" it and put up a fake, high number.
With a Mustang load dyno, your readings will be all over the place depending on how fast the operator brings the load in, and at what RPM. Too much human factor.
Based on what I have read, there is simply no other dyno that can do what the Dyno Dynamics dyno can.
Matt, Sleddy, and others-- you should know better than to be flaming JED. Let's face it, there's a long and ugly history of naysaying on TDR. It wasn't too long ago when we were hearing things like:
-- 500hp is a myth (busted)
-- Twin turbos won't work (wrong)
-- a 24V can't make over 500hp (wrong)
-- You can't pull with an auto trans (wrong)
-- SuperMentals are the ragged edge of streetable (now we see 150hp and 180hp injectors on the street all the time)
Etc etc-- the point being that time and technology march on.
It's embarassing that JED comes on here with nothing but sincerity and clear-thinking backup of his products and gets flamed.
I think the real root of the problem is that a LOT of TDR members are in love with the "dyno proven power" number that they have, and aren't willing to have the number humbled.
Anyone believe that I made almost 400 "dyno proven hp" with just DD2s and an EZ. Heck no. I'd be surprised if it was over 335. Now I'll brag that number just like any other poser, but I know in my heart that it's a charade.
The problem is just dyno and operators. The problem is HOW WE THINK OF POWER. I've said it before, I'll say it again. All that matters is performance in a given application. If you are racing a 3400lb car, than all that matters is how quickly that engine can recover after being yanked down a couple thousand RPM (upshift) against a 3400lb load. One engine may dyno 100hp less, but if it will pick up RPM faster against that 3400lb car's load, it will ALWAYS be faster on the track, no matter what the dyno says.
If you are dragging 80K worth of frozen chicken up a grade for Tyson foods, then all that matters is how much grunt that engine can dish out before it has to downshift. In this case, it's not about the ability to gain RPM (at constant load) so much as the ability to keep from losing RPM (against increasing load)-- which is entirely different.
Take a PSD that makes a constant 400lb-ft from 2K rpm to 3K rpm. Take a CTD that makes a constant 400lb-ft from 2K rpm to 3K rpm. The CTD would probably perform better up a grade, but the PSD would take it at the track every time. A V8 will simply rev faster than a heavy-component I6. It will take it's 400 lb-ft and put it to the track faster. How many inline engines are in auto racing? Nascar? F1? Drag racing? All are Vees of 8-12 cylinders. How many V-12s are there in tractor-trailers? Does it matter if a class 8 tractor revs quickly?
If you're thinking about performance (and dynos that purport to measure performance), you have to keep in mind what you define performance as-- and keep everything in a frame of reference.
JMHO
TDR has turned off a lot of folks with the know-it-all attitude of some members (I'm as guilty as anyone at times, though I'm much less qualified).
There are a lot of lone-wolf bombers who are making big HP, and did it without a TDR membership.
I guess I see a lot of myself in JED. I also think that East vs West is childish BS.
Sleddy-- TQ is important, yes, but EVERYTHING that JED said is true. You CAN build 1000lb-ft with a long lever. How much work is going to be done? Not much, unless you can run really fast.
TQ is important because it tells you how much work you could theoretically do. Like, it will tell you if you can pull only a 2K# tagalong vs a 40K# sled.
But HP is even more important because it adds the element of time. THIS is significant because HP allows you to trade rpm for torque with gear reduction. THIS is why the 345hp Hemi will often tow as well as a stock CTD.
If you wanted to, you could pull a Class 8 trailer with a 900hp formula 1 engine spinning 16K rpm. Would it last long? Maybe not. Maybe so, though. The actual load on the engine after the quadruple-or-more gear reduction is probably very little.
Now, where your engine make its power will determine how well it does certain things. But we also can't separate the engine from its packaging. We won't take a high-revving motorcycle engine and drop it in a Dodge, and we aren't revving a CTD to 13K rpm.
A pulling engine doesn't need to make much low end power at all. If it did, you wouldn't see the huge, unstreetable turbo(s) they use. All a good pulling engine needs to do is make good power (torque) while the RPM is bouncing off the governor. So if your turbos don't spool till 2500 rpm, no one cares.
A drag engine must have good power from launch. This is why we have higher stall converters to allow the engine to spin up to where it makes more power (torque). Drag racers will always tell you that they try to match a converter's stall speed to the tq peak of the engine.
A street engine needs quick spoolup and a broad, usable powerband.
A dyno engine (dyno in this case being 248c) is also built differently. A dyno engine just has to have a good, fast torque rise to get the roller spinning. The farther and faster this tq rise happens, and the higher the rpm can be sustained, then the more "power" it will make.
In each case, the more you optimize an engine for a certain application (street, race, pull, dyno), the more specialized and inflexible it becomes.
At a constant RPM, torque IS power, and hp is torque. The rpm just determines the ratio (because of the time element).
The beauty of the Dyno Dynamics dyno is that it can vary any combination of parameters to keep any other combination of parameters constant. If you want to test EGT at constant rpm as load is applied, you can do that. You want to see how fast your truck moves a 3K# load vs a 15Klb load-- you can do that. You want to see the correlation of boost to RPM as load is varied or rpm is varied, you can do that.
With a Dynojet, you have to change the drum to change the load. A fast torque rise with a light drum can "spike" it and put up a fake, high number.
With a Mustang load dyno, your readings will be all over the place depending on how fast the operator brings the load in, and at what RPM. Too much human factor.
Based on what I have read, there is simply no other dyno that can do what the Dyno Dynamics dyno can.
Matt, Sleddy, and others-- you should know better than to be flaming JED. Let's face it, there's a long and ugly history of naysaying on TDR. It wasn't too long ago when we were hearing things like:
-- 500hp is a myth (busted)
-- Twin turbos won't work (wrong)
-- a 24V can't make over 500hp (wrong)
-- You can't pull with an auto trans (wrong)
-- SuperMentals are the ragged edge of streetable (now we see 150hp and 180hp injectors on the street all the time)
Etc etc-- the point being that time and technology march on.
It's embarassing that JED comes on here with nothing but sincerity and clear-thinking backup of his products and gets flamed.
I think the real root of the problem is that a LOT of TDR members are in love with the "dyno proven power" number that they have, and aren't willing to have the number humbled.
Anyone believe that I made almost 400 "dyno proven hp" with just DD2s and an EZ. Heck no. I'd be surprised if it was over 335. Now I'll brag that number just like any other poser, but I know in my heart that it's a charade.
The problem is just dyno and operators. The problem is HOW WE THINK OF POWER. I've said it before, I'll say it again. All that matters is performance in a given application. If you are racing a 3400lb car, than all that matters is how quickly that engine can recover after being yanked down a couple thousand RPM (upshift) against a 3400lb load. One engine may dyno 100hp less, but if it will pick up RPM faster against that 3400lb car's load, it will ALWAYS be faster on the track, no matter what the dyno says.
If you are dragging 80K worth of frozen chicken up a grade for Tyson foods, then all that matters is how much grunt that engine can dish out before it has to downshift. In this case, it's not about the ability to gain RPM (at constant load) so much as the ability to keep from losing RPM (against increasing load)-- which is entirely different.
Take a PSD that makes a constant 400lb-ft from 2K rpm to 3K rpm. Take a CTD that makes a constant 400lb-ft from 2K rpm to 3K rpm. The CTD would probably perform better up a grade, but the PSD would take it at the track every time. A V8 will simply rev faster than a heavy-component I6. It will take it's 400 lb-ft and put it to the track faster. How many inline engines are in auto racing? Nascar? F1? Drag racing? All are Vees of 8-12 cylinders. How many V-12s are there in tractor-trailers? Does it matter if a class 8 tractor revs quickly?
If you're thinking about performance (and dynos that purport to measure performance), you have to keep in mind what you define performance as-- and keep everything in a frame of reference.
JMHO
Justin,
I am glad your on his side.
Most of the time you don't know what your talking about either!! :-laf :-laf :-laf
JK! AHAHAHH!
:--)
I am glad your on his side.
Most of the time you don't know what your talking about either!! :-laf :-laf :-laf
JK! AHAHAHH!
:--)
Hohn said:
Point taken but not all true... . If that is the case how come I know of 3 CTD's dragsters and no offical V8 powered diesel dragsters??? How come some people yank out there V8 diesels and put in a CTD for quicker ET's.
I do realise that V's will rev quicker like a V8 vs I8. But will not aways out perform an inline even for racing.
Honestly I really dont know **** but I thought i would say this.
Hohn,
You are missing the point, as well.
You are missing the point, as well.
Last edited:
You guys seem to be thinking in the flywheel realm of HP and TQ measurement, but it's what is at the rear wheels that really differentiates between one truck vs. another in a race.
First, you have Torque
Torque is F dot d - the cross product of the force * the moment arm. Now force is obviously what pushes your truck forward, and is the force you feel when you accelerate.
The real question is - which torque? It's not flywheel torque that actually moves your truck, but rather "delivered torque", or torque * gear multiplication. This is why you accelerate faster in first gear than in third (ignoring wind resistance and turbo lag... i. e. you can't make the boost in 1st that you can in 6th).
How does this work? Say at we have 800 ft-lbs of torque available at an rpm. Now in first let’s say a 5:1 transmission gear and 4:1 rear gear (to make math easier) - so a final drive ratio of 20:1. So in first gear we will have 800 * 20 = 16000 ft-lbs of torque pushing us forward. Say second gear is 3. 5:1 - so we have 800 * 3. 5 * 4 = 11200 ft-lbs of torque pushing us forward. 16000 is obviously more than 11200, and accounts for that difference. Note that in this case tire size also affects the torque delivered to the ground. In this case, the taller the tire you have the longer the lever arm and thus the less force delivered to the tire's contact patch.
Now let's look at this a little differently. Gearing is fixed for each gear, so velocity and rpm are related.
Say we have 800ft-lbs of torque @ 2000, and 350hp at 3000 rpm (only 613 ft-lbs).
Now lets say we are at a certain velocity where we could be in first gear (5:1 gear reduction) at 3000 rpm, or second gear (3. 5:1 gear reduction) at 2000 rpm.
Now in second gear (most flywheel torque) we have 3. 5:1 gear reduction * 800 ft-lbs of torque, or 2800 ft-lbs delivered at the rear end
In first gear we only have 350hp * 3000/5252 = 613 ft-lbs of flywheel torque, but it is multiplied by 5:1, so we have 3065 ft-lbs of torque delivered.
Now it's obvious that 3065 ft-lbs at the rear wheel will accelerate you quicker than 2800 ft lbs, so first is better than second here. Nevermind the fact that you're almost on the limiter, but you should get the point. Basically it's torque delivered, or the product of flywheel torque * gear multiplication that matters.
So what about horsepower?
We determined above that acceleration is determined by
Flywheel torque * gear multiplication.
Well what is flywheel torque - it is basically the rotational analogue of force.
What determines gear multiplication? Well, you have a fixed set of ratios in the transmission (not a CVT transmission) so what determines what gear you can be in? Velocity (road speed.
So in other words acceleration is proportional to
Force * velocity.
How convenient! There is an equation for power that says
Power = Force * Velocity!
Horsepower is telling us what the magnitude (proportionally) of the product of flywheel torque * gear multiplication will be - or at least when it will be maximized and minimized.
So, if you maximize area under the hp curve, you are maximizing this product, and thus your acceleration. HP simply takes velocity into consideration (rate at which work can be applied), so you don't have to worry about gear ratio's, etc. However, when noting gear ratios, you will see that you should always start any race from a roll with the combo of gearing, RPM, and torque delivered to give you the best punch from the start.
Thus comes the old adage, it takes torque (at the wheels!) to get the load moving, but HP to win the race to the top.
First, you have Torque
Torque is F dot d - the cross product of the force * the moment arm. Now force is obviously what pushes your truck forward, and is the force you feel when you accelerate.
The real question is - which torque? It's not flywheel torque that actually moves your truck, but rather "delivered torque", or torque * gear multiplication. This is why you accelerate faster in first gear than in third (ignoring wind resistance and turbo lag... i. e. you can't make the boost in 1st that you can in 6th).
How does this work? Say at we have 800 ft-lbs of torque available at an rpm. Now in first let’s say a 5:1 transmission gear and 4:1 rear gear (to make math easier) - so a final drive ratio of 20:1. So in first gear we will have 800 * 20 = 16000 ft-lbs of torque pushing us forward. Say second gear is 3. 5:1 - so we have 800 * 3. 5 * 4 = 11200 ft-lbs of torque pushing us forward. 16000 is obviously more than 11200, and accounts for that difference. Note that in this case tire size also affects the torque delivered to the ground. In this case, the taller the tire you have the longer the lever arm and thus the less force delivered to the tire's contact patch.
Now let's look at this a little differently. Gearing is fixed for each gear, so velocity and rpm are related.
Say we have 800ft-lbs of torque @ 2000, and 350hp at 3000 rpm (only 613 ft-lbs).
Now lets say we are at a certain velocity where we could be in first gear (5:1 gear reduction) at 3000 rpm, or second gear (3. 5:1 gear reduction) at 2000 rpm.
Now in second gear (most flywheel torque) we have 3. 5:1 gear reduction * 800 ft-lbs of torque, or 2800 ft-lbs delivered at the rear end
In first gear we only have 350hp * 3000/5252 = 613 ft-lbs of flywheel torque, but it is multiplied by 5:1, so we have 3065 ft-lbs of torque delivered.
Now it's obvious that 3065 ft-lbs at the rear wheel will accelerate you quicker than 2800 ft lbs, so first is better than second here. Nevermind the fact that you're almost on the limiter, but you should get the point. Basically it's torque delivered, or the product of flywheel torque * gear multiplication that matters.
So what about horsepower?
We determined above that acceleration is determined by
Flywheel torque * gear multiplication.
Well what is flywheel torque - it is basically the rotational analogue of force.
What determines gear multiplication? Well, you have a fixed set of ratios in the transmission (not a CVT transmission) so what determines what gear you can be in? Velocity (road speed.
So in other words acceleration is proportional to
Force * velocity.
How convenient! There is an equation for power that says
Power = Force * Velocity!
Horsepower is telling us what the magnitude (proportionally) of the product of flywheel torque * gear multiplication will be - or at least when it will be maximized and minimized.
So, if you maximize area under the hp curve, you are maximizing this product, and thus your acceleration. HP simply takes velocity into consideration (rate at which work can be applied), so you don't have to worry about gear ratio's, etc. However, when noting gear ratios, you will see that you should always start any race from a roll with the combo of gearing, RPM, and torque delivered to give you the best punch from the start.
Thus comes the old adage, it takes torque (at the wheels!) to get the load moving, but HP to win the race to the top.
Last edited:
Comparing our diesel to a drag car motor is totally a different ball game. Most drag cars run higher stall convereters for a simple fact. Their motors are not making the power down low in the rpm band. The camshafts along with compression decide where there power band will be, which is usually up high. They make hardly any torque down low, so they have to run a looser converter to get in there usable power range sooner. If they had the stump pulling low end torque that we do they would run a tighter converter also and make the torque work for them. Take a 220 HP 4 cylinder gas motor out of an import. Do you really think it is going to propel your 7500-8000 lb truck like a comparable diesel would (like in a 225 HP 2nd gen truck). Better yet, will you use that 220 HP with 200 ft lbs tq to tow a trailer? Probably not.
When you guys say TQ doesn't matter you are just fooling yourselfs.
When you guys say TQ doesn't matter you are just fooling yourselfs.
lmills said:
??? What are you talking about?
We are talking about getting the power to the ground.
Simply,,, you need to match your Torque Converter to your peak torque.
A 502 Big Block with a towing cam would need a lower than factory stall converter, our diesel's also need a much lower than factory stall convevrter.
The little imports has to spike his RPM just a couple thousand RPM before redline,,, to get into HIS torque band.
I like to look at the HP-TQ argument this way...
500 Ft Lbs torque with 100HP gets a big load moving very slowly. (Imagine a stock 1st gen Cummins)
500 Ft Lbs with 325HP gets a big load moving very quickly.
500 Ft Lbs with 600HP gets a big load moving even faster.
Now, 1,000 Ft Lbs with 500HP gets the job done in style
Merrick
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The Perfect Collection
The Perfect Collection Vol. II
TSB Updates
Dodge/Cummins Historical Overview
Cameron Collection
What Makes Us Tick?
Product Showcase
Advertising
