Forum Discussion
ShinerBock wrote:
:B Finally someone gets it.Cummins12V98 wrote:
Don't see any pizzing going on. RAM put their claims out there a few years ago and ARE SAE rated. Ford finally came to the table in 2017 with their 350's and are similarly SAE rated.
At 23K I would be on the edge with a GM. When I hook my MotorCycle trailer with two Cruisers to the back of my 5er I will be well over GM's rating.
Like I have said if GM could pass the SAE test at the higher ratings I am sure they would.
I have no doubts GM could pass with a higher rating, but just because you can pass with a higher rating doesn't mean you have to post that rating for your truck. The SAE J2807 never states that you can't rate your truck lower than the weight that truck is J2807 certified at. You just can't rate it higher and be J2807 certified. I will try to find the video I have seen where a GM rep clearly states that their HD passed the J2807 with much higher ratings, but they don't feel that only being able to do 30 mph is towing. When I find it I will post it.
Ford and Ram could do the same, but they are in this proverbial pissing match to claim the useless "best in class" title.Cummins12V98 wrote:
Don't see any pizzing going on. RAM put their claims out there a few years ago and ARE SAE rated. Ford finally came to the table in 2017 with their 350's and are similarly SAE rated.
At 23K I would be on the edge with a GM. When I hook my MotorCycle trailer with two Cruisers to the back of my 5er I will be well over GM's rating.
Like I have said if GM could pass the SAE test at the higher ratings I am sure they would.
I have no doubts GM could pass with a higher rating, but just because you can pass with a higher rating doesn't mean you have to post that rating for your truck. The SAE J2807 never states that you can't rate your truck lower than the weight that truck is J2807 certified at. You just can't rate it higher and be J2807 certified. I will try to find the video I have seen where a GM rep clearly states that their HD passed the J2807 with much higher ratings, but they don't feel that only being able to do 30 mph is towing. When I find it I will post it.
Ford and Ram could do the same, but they are in this proverbial pissing match to claim the useless "best in class" title.- Don't see any pizzing going on. RAM put their claims out there a few years ago and ARE SAE rated. Ford finally came to the table in 2017 with their 350's and are similarly SAE rated.
At 23K I would be on the edge with a GM. When I hook my MotorCycle trailer with two Cruisers to the back of my 5er I will be well over GM's rating.
Like I have said if GM could pass the SAE test at the higher ratings I am sure they would. - Bottom line for me is all 3 trucks are more than capable of doing their jobs so as far as the dyno readings which are not real anyway due to different programming are just BS anyway.
But it does give yall something to talk about. FishOnOne wrote:
Perhaps this is why GM specs in a max tow rating of 23k lbs and it allows the truck to run in it sweet spot so to speak.
Could be. Although, I do like the fact that GM is choosing not to get into this useless 30k towing "best in class" pissing match that Ram and Ford are in right now.ShinerBock wrote:
Huntindog wrote:
So what do you think caused it?
The DA combo has been dynoed many times over the years and has consistently put more power to the ground than higher rated trucks.
And in the recent Ike hill climb, it also put more power to the ground.
Yet this dyno test is inconsistent (by a HUGE margin) with those other tests.
You can't compare one dyno to another completely different dyno. There are many different factors effecting their numbers like humidity and altitude just to name a few. Then there is the fact that some dyno types tend to post higher number than others. The main thing about this dyno was the the fact that all three were tested on the same day and the same dyno. This is more of a real comparison than comparing a dyno done one two different dyno's at two different altitudes.
As I said before, I think the main reason why the GM posted the better time up the Ike was mainly due to the 3.73 and transmission gears allowing it to be in in third gear at a higher rpm where it is making more power compared to the others that were in fourth most of the way at lower rpm where they are not making peak power. If they manually would have dropped the Ram or Ford down a gear, then it probably would have had an effect on the times. However, that is not how they run their tests so it is what it is.
Perhaps this is why GM specs in a max tow rating of 23k lbs and it allows the truck to run in it sweet spot so to speak.Turtle n Peeps wrote:
4x4ord wrote:
One truck can put 10,000 lb ft of torque to the rear axle and a second truck can put 20,000 lb ft of torque to its rear axle...Who is faster up the hill? There is no way of even guessing without knowing the rpm (or power). Now if we know the first truck has a 400 hp engine and the second truck only 200 we can have a high level of confidence that the 400 hp truck wins.
Someone gets it for once on this site!
Someone please make this post a sticky at the top and make it mandatory to read it before they can sign up! :B
While that is generally true, it is not true all the time. It is not about how much power an engine makes at peak. It is about how much power the engine/truck makes at the rpm and gear that the torque limits it to. Horsepower is derived from rpm and torque so if the vehicle does not have enough torque to over come the load at the rpm it makes peak horsepower, then it is making less than peak power.
If the 400 hp vehicle is only limited to a an rpm where it is making less then half its power, then the 200 hp engine will win if it has enough torque to pull the load at peak power. Gears also limit speed. If you do not have enough torque to pull a hill in 4th and you loose speed in that gear, then the vehicle will be limited to 3rd which will also limit its speed regardless if it has more horsepower or not.
Then there is the factor of power loss due to altitude with N/A engines and FI engines where the lower powered FI engine will blow the doors of the higher powered N/A engine. Even two FI engine turbochargers may act differently at elevation with one having a more efficient blade and bearing allowing for higher turbo rpms to greater compensate for the pressure loss. We have seen this many times on the Ike.
There is also the factor of how each manufacturer is attaining that power numbers. If they each use one of the three different SAE standards to achieve their power numbers with one standard generally giving a higher number than the other standard, then engine with the higher power rating may not actually have more power. It may actually have less or the same power if they both used the same standard, but due to the standard they use it shows more power.Huntindog wrote:
So what do you think caused it?
The DA combo has been dynoed many times over the years and has consistently put more power to the ground than higher rated trucks.
And in the recent Ike hill climb, it also put more power to the ground.
Yet this dyno test is inconsistent (by a HUGE margin) with those other tests.
You can't compare one dyno to another completely different dyno. There are many different factors effecting their numbers like humidity and altitude just to name a few. Then there is the fact that some dyno types tend to post higher number than others. The main thing about this dyno was the the fact that all three were tested on the same day and the same dyno. This is more of a real comparison than comparing a dyno done one two different dyno's at two different altitudes.
As I said before, I think the main reason why the GM posted the better time up the Ike was mainly due to the 3.73 and transmission gears allowing it to be in in third gear at a higher rpm where it is making more power compared to the others that were in fourth most of the way at lower rpm where they are not making peak power. If they manually would have dropped the Ram or Ford down a gear, then it probably would have had an effect on the times. However, that is not how they run their tests so it is what it is.ktmrfs wrote:
So what do you think caused it?Huntindog wrote:
Perhaps the hood scoop is the reason the Dmax didn't dyno well.
A scoop would be pretty ineffective on a dyno.
It is very strange that the so called power loss is so high due to "drivetrain loss".
This is an area where the Dmax has always shined.
doubt the hood scoop had any effect. since duramax HP is the SAE certified spec, it is done with the engine stationary on a stand so any ram effect from speed isn't taken into account.
The DA combo has been dynoed many times over the years and has consistently put more power to the ground than higher rated trucks.
And in the recent Ike hill climb, it also put more power to the ground.
Yet this dyno test is inconsistent (by a HUGE margin) with those other tests.
