Need Help Understanding Power-Tripp

dobro

Supercharged
Joined
Dec 29, 2012
Messages
397
Location
Florida, USA
Ride
2011 R3T
On 7-29-11 Power-Tripp wrote: "You are going to want to be around 13.0-13.1 at peak power (6000 rpm) at WOT, tapering to 13.2 at 6500 rpm. At peak torque rpm, you are going to want to be a bit richer ~12.8-12.9. At part throttle work a few tenths leaner, and at cruise, run at Stoichiometric."

My questions are these: (1) What is generally considered to be "peak torque" on an R3T? (2) What is "at cruise"? (3) What does he mean by "At part throttle work a few tenths leaner"? How much per each step down in throttle reduction? Does he mean that at every rpm level the AFR should be reduced with each step down reduction of throttle from WOT? (4) Is stoichiometric actually 14.2?

Thanks.
 
With the R3T you can load the revised tune that unlocks 30 HP and or get a Dobeck Performance AFR Plus. I have the Dobeck on my standard and love it. It unlocks plenty of extra power and takes care of all of those AFR changes and is reprogrammable any time you want. Very nice device for the folks who don't want to be spending crazy bank with a dyno tuner. I loaded the R3T revised tune in my friends R3T and he is very happy with the power boost. Revised tune is R3T stock or slip-on 20368.
 
With the R3T you can load the revised tune that unlocks 30 HP and or get a Dobeck Performance AFR Plus. I have the Dobeck on my standard and love it. It unlocks plenty of extra power and takes care of all of those AFR changes and is reprogrammable any time you want. Very nice device for the folks who don't want to be spending crazy bank with a dyno tuner. I loaded the R3T revised tune in my friends R3T and he is very happy with the power boost. Revised tune is R3T stock or slip-on 20368.

Idaho, I have a PC5 (but am too far away from a dynotuner I trust so I have a canned dynotune) and when I get an autotune I'm going to try Hanso's new tune (if he agrees). Right now I want to understand what Wayne's post means so I can evaluate the AFR settings in my current ecu tune (20367) and tweak the PC5 if the ecu tune is too lean.
 
On 7-29-11 Power-Tripp wrote: "You are going to want to be around 13.0-13.1 at peak power (6000 rpm) at WOT, tapering to 13.2 at 6500 rpm. At peak torque rpm, you are going to want to be a bit richer ~12.8-12.9. At part throttle work a few tenths leaner, and at cruise, run at Stoichiometric."

My questions are these: (1) What is generally considered to be "peak torque" on an R3T? (2) What is "at cruise"? (3) What does he mean by "At part throttle work a few tenths leaner"? How much per each step down in throttle reduction? Does he mean that at every rpm level the AFR should be reduced with each step down reduction of throttle from WOT? (4) Is stoichiometric actually 14.2?

Thanks.

Peak torque for a standard Rocket engine without new cams or pistons is about 2700-3000 rpm. Cruising could be considered 5th gear at 70 mph, about 3000 rpm on my 2005.
 
Idaho, I have a PC5 (but am too far away from a dynotuner I trust so I have a canned dynotune) and when I get an autotune I'm going to try Hanso's new tune (if he agrees). Right now I want to understand what Wayne's post means so I can evaluate the AFR settings in my current ecu tune (20367) and tweak the PC5 if the ecu tune is too lean.

1: Peak Torque is the RPM at which your engine makes the highest torque. At this RPM cylinder pressure is highest and pushing on the crank the hardest, as the highest pressure point, it is required to richen the mixture for safety and to further increase the amount of torque created. For stock roadsters, target 2800 as peak torque and you will be close.

2: Cruise is when you are maintaining a steady speed at a steady RPM with a steady throttle position. It is usually a very low load condition requiring very little power and since it is such a light load, it can run a leaner mixture safely to conserve fuel.

3: The leaning a few tenths part. He means lean out the mixture from say 13.1 at WOT to 14.5 at low load/low RPM cruise. As you increase throttle inputs make a smooth curve which increases the AFR from 14.5 to 13.1 in smooth increments to maintain a safe/healthy mixture as the load gradually increases.

4: Stoichiometric mix for gasoline is 14.7:1, as most people round it. In reality, with ethanol added to gas in our world it will be slightly more rich, like 14.5 +/- a tenth or two. It is perfectly safe to cruise down the freeway at 60mph, 2-3 % throttle, with 14.7 or 15 to 1 ratios. Zero risk to the motor whatsoever.
 
1: Peak Torque is the RPM at which your engine makes the highest torque. At this RPM cylinder pressure is highest and pushing on the crank the hardest, as the highest pressure point, it is required to richen the mixture for safety and to further increase the amount of torque created. For stock roadsters, target 2800 as peak torque and you will be close.

2: Cruise is when you are maintaining a steady speed at a steady RPM with a steady throttle position. It is usually a very low load condition requiring very little power and since it is such a light load, it can run a leaner mixture safely to conserve fuel.

3: The leaning a few tenths part. He means lean out the mixture from say 13.1 at WOT to 14.5 at low load/low RPM cruise. As you increase throttle inputs make a smooth curve which increases the AFR from 14.5 to 13.1 in smooth increments to maintain a safe/healthy mixture as the load gradually increases.

4: Stoichiometric mix for gasoline is 14.7:1, as most people round it. In reality, with ethanol added to gas in our world it will be slightly more rich, like 14.5 +/- a tenth or two. It is perfectly safe to cruise down the freeway at 60mph, 2-3 % throttle, with 14.7 or 15 to 1 ratios. Zero risk to the motor whatsoever.
Smarty pants , my brain hurts :)
 
<3 nice to see you around wrecka.

Dobro,
Don't get tied around the AFR table in any rocket tune. The bike does not have the ability to adjust to it, nor can it be given that ability. That is what the autotune modul for pc5 is for, or a dobeck.

Long explanation short version: it's a cute little 99% useless table at anything besides idle and very light cruise.

Long explanation long version:

Rocket Oxygen sensors are narrow band sensors. As a narrow band sensor it can do exactly 1 thing and 1 thing only, report the exhaust mixture as either more or less rich than stoichiometric. It swings back and forth very quickly. Modern engines will attempt to adjust to 14.7:1 based on the "count" of time on either side of 14.7:1 by either adding or removing fuel. As such a limited use device, nearly all modern vehicles either completely ignore it at moderate/high loads, or they weight it's input in the fuel calculation at near zero. That is the reason in my tunes you see numbers, all pretty and gradual and such making a cute little graph, because they mean nearly nothing at all. That is also why I turn it off on my bike, I have a wideband sensor that is capable of actual accurate reporting, so I disable the stock O2 function in the ECU to keep it from making adjustments, then make adjustments myself via data loggging results and wideband readings at a given RPM/Throttle Position/MAP signal.
 
OK, then I should rephrase my post..... Bear in mind most folk will hardly ever use peak torque at 2700 rpm as it is acheived at wide open throttle and this is rarely used for more than maybe 1/2 a second. This is because the engine at peak torque is pulling hard and will go past 2700rpm as you are opening the throttle. If you have it pinned before 2700 rpm it will pull thru this area very quickly to go onto maybe 2751 rpm or even more ! For what it is worth peak torque on a bone stock R3 is about 3400rpm. Have a nice day . :).
 
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