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torque and fuel dyno charts
- Thread starter duc
- Start date
Thanks Duc, not too bad except for the AFR. For those getting dyno runs on a Dynojet Dyno, take a memory stick and have the shop drop all of the *.drf files onto it for you to send to me if you would.
What fueling mods do you have done?
What fueling mods do you have done?
Spaceclam
Cruisin' Guzzisti
if you are making 77hp and it's not a full throttle run, than what % of throttle are these charts for?
Todd I am not up on dynos a lot but loren showed m on the dynojet compter my full throttle run was 78.32 hp and the max torque was around 61 ft lbs.This was using your race ecu for the base and correcting from there.He showed me the actual map numbers, had to ad fuel at the bottm and took away at the top I did not bother getting him to print me a copy,sori.
The bike has open air box mistral pipe your ecu the usual get rid of the canister block off the stepper motor etc.Hope this also answers you qustion clam.
The bike has open air box mistral pipe your ecu the usual get rid of the canister block off the stepper motor etc.Hope this also answers you qustion clam.
Spaceclam
Cruisin' Guzzisti
I noticed you dont seem to have that notorious torque dip between 4 and 5k. i would REALLY like to know what makes yours so special.
Clam,nothing special or different about the bike other than what I stated nothing else done.Loren did show me a lot of previous fuel curves he did on different runs before stopping where it is now.Some were really lean going as high as into the 15,s you notice the map has just a little variation in the 4 to 5 range but is really very good.I can not say enough about how well it feels
when you get on,not just 1st and second but every gear!wish I could give you more info but that,a about it.
Duc
when you get on,not just 1st and second but every gear!wish I could give you more info but that,a about it.
Duc
Mi_ka
High Miler
GT-Rx said:
The same goes for me for Fuchs benches:
If someone gets a dyno run on a Fuchs dyno ask for the XXX.pui file in the "c:/moto/essai" folder (where XXX the id the run was saved as). I'd want a copy of the file, if it is no fuss.
On a Fuchs dynamometer you will get different numbers, usually less, do not worry, there are differences between the various bench brands - I'd be glad to help clarify differences over Dynojet numbers.
Clam, I did think of one thing that might make some difference,not sure.Although I read all the warnings about the sacred screw
I adjusted my idle just a little higher using it and the tps ended up being set at 5.2,Ran much better this way so thats how we left
it.If you are at 4.8 and raise they Idle to around 1175 to1200 the tps falls between 5.0 and 5.2.This may have absolutley nothing to do with the torque curve but is the only thing that is any different I can think of.
I adjusted my idle just a little higher using it and the tps ended up being set at 5.2,Ran much better this way so thats how we left
it.If you are at 4.8 and raise they Idle to around 1175 to1200 the tps falls between 5.0 and 5.2.This may have absolutley nothing to do with the torque curve but is the only thing that is any different I can think of.
Spaceclam
Cruisin' Guzzisti
It will a little bit, because you are advancing the fuel/ignition curve without changing the position of your throttle grip. Meaning you are giving it more fuel and more spark advance per throttle position. Although i'm not sure what happens between range when the TPS reads 100% and the throttle grip hits the stop.
Mine idles at 1k to the dot.
Mine idles at 1k to the dot.
Clam it is very easy to experiment and be ablto go back original,Just use avery small fine tip black marker and mark position of screw,turn clockwise to advance idle and tps if you have vdsts you can watch tps as you dial it in.Mine always sets to at least 4.8 when I reset it that is a lilltle higher than most.If you do try it let me know.
Duc
Duc
Spaceclam
Cruisin' Guzzisti
I know the vstd shows this, but it just doesn't makes sense.
I have never encountered an engine in my life that retards timing (spark goes off later) as the engine speeds up.
The idea of spark advance, of course, is to achieve peak cylinder pressure AFTER the piston reaches top dead center. Fuel takes time to burn, so if the engine is spinning faster, the spark must happen EARLIER in order to achieve this
If the idle had a high degree of advance, it would be prone to detonating or kicking back, because the spark happens before TDC but the fuel burns nearly instantly in comparison to the motion of the piston, thus peak cylinder pressure is reached before TDC.
If higher rpms had a low degree of advance, the burn wouldn't complete since everything is moving real fast. This would lead to low power output.
On airplane engines, this is evidenced by mechanical devices called impluse couplings. They delay ignition by a number of degrees (usually in the really low double digits) and they wont start without them, because the engines will kick back otherwise.
To take the example to extremes, let's say that we have an engine, and we want the peak pressure to develop after TDC (as with all engines) but let's give it a number. say 10 degrees after TDC.
Let's say this engine had a real big flywheel, and could operate at 1 rpm. To achieve proper timing of peak pressure, the spark would have to go off at almost exactly 10 degrees after TDC, because the fuel burns instantly compared to the motion, and the pressure will build to peak before the engine moves too far.
Now let's speed this engine up to 20,000 rpm. If we lit the fuel off at 10 degrees ATDC as before, almost none of the fuel would be burnt by the time the piston reaches the exhaust stroke. Thus the timing must be advanced, and happen EARLIER in the cycle. In fact, the spark would have to happen BEFORE TDC. The building of pressure from ignition, and compression, are necessary to "cushion" the piston at these speeds, otherwise you'd stretch a rod and you'd blow stuff up for sure.
I think perhaps the confusion lies in the fact that what you mean by "ADVANCED' timing means the spark happens farther forward in the rotation of the crank (meaning the spark goes off closer to TDC, or fewer degrees before TDC)
IN any case, if the TPS thinks the throttle is open more than it is, the spark will happen earlier in the rotation. (more degrees before TDC) Perhaps the VSTD measures DEGREES FROM FULL ADVANCE?
I have never encountered an engine in my life that retards timing (spark goes off later) as the engine speeds up.
The idea of spark advance, of course, is to achieve peak cylinder pressure AFTER the piston reaches top dead center. Fuel takes time to burn, so if the engine is spinning faster, the spark must happen EARLIER in order to achieve this
If the idle had a high degree of advance, it would be prone to detonating or kicking back, because the spark happens before TDC but the fuel burns nearly instantly in comparison to the motion of the piston, thus peak cylinder pressure is reached before TDC.
If higher rpms had a low degree of advance, the burn wouldn't complete since everything is moving real fast. This would lead to low power output.
On airplane engines, this is evidenced by mechanical devices called impluse couplings. They delay ignition by a number of degrees (usually in the really low double digits) and they wont start without them, because the engines will kick back otherwise.
To take the example to extremes, let's say that we have an engine, and we want the peak pressure to develop after TDC (as with all engines) but let's give it a number. say 10 degrees after TDC.
Let's say this engine had a real big flywheel, and could operate at 1 rpm. To achieve proper timing of peak pressure, the spark would have to go off at almost exactly 10 degrees after TDC, because the fuel burns instantly compared to the motion, and the pressure will build to peak before the engine moves too far.
Now let's speed this engine up to 20,000 rpm. If we lit the fuel off at 10 degrees ATDC as before, almost none of the fuel would be burnt by the time the piston reaches the exhaust stroke. Thus the timing must be advanced, and happen EARLIER in the cycle. In fact, the spark would have to happen BEFORE TDC. The building of pressure from ignition, and compression, are necessary to "cushion" the piston at these speeds, otherwise you'd stretch a rod and you'd blow stuff up for sure.
I think perhaps the confusion lies in the fact that what you mean by "ADVANCED' timing means the spark happens farther forward in the rotation of the crank (meaning the spark goes off closer to TDC, or fewer degrees before TDC)
IN any case, if the TPS thinks the throttle is open more than it is, the spark will happen earlier in the rotation. (more degrees before TDC) Perhaps the VSTD measures DEGREES FROM FULL ADVANCE?
In my experience, you increase advance as rpm increases(up to a point and then you decrease it again).
You decrease advance as engine load increases.
Modern bikes like Guzzi's are not limited to just looking at rpm. I would think they use throttle position to determine engine load and rpm to determine engine speed. Therefore it makes sense that the ignition advance would decrease if rpm stayed the same and the throttle position (TPS) increased.
You decrease advance as engine load increases.
Modern bikes like Guzzi's are not limited to just looking at rpm. I would think they use throttle position to determine engine load and rpm to determine engine speed. Therefore it makes sense that the ignition advance would decrease if rpm stayed the same and the throttle position (TPS) increased.
Spaceclam
Cruisin' Guzzisti
That is true, but that is not what was being done when this observation was reported.
HOwever, guzzimoto is right that as you open the throttle but keep rpm the same, vaccum decreases, in the end causing higher dynamic compression. This higher pressure mixture burns faster, thus less advance is needed.
THis observation however was made with the engine unloaded, in neutral, slowly increasing the throttle, with the engine following suit.
HOwever, guzzimoto is right that as you open the throttle but keep rpm the same, vaccum decreases, in the end causing higher dynamic compression. This higher pressure mixture burns faster, thus less advance is needed.
THis observation however was made with the engine unloaded, in neutral, slowly increasing the throttle, with the engine following suit.
I believe the initial observation was about adjusting the "sacred screw" to increase the idle speed and it's potential effect on TPS values.
Personally I don't think it would have a impact on how the motor ran unless you adjusted the "sacred screw" and then reset the TPS. The TPS value at idle will increase if you adjust the "sacred screw", but it will have no impact on the TPS value at WOT. Adjusting the screw is no different then the fast idle on a V11 or cracking the throttle open until you reset the TPS.
What I gather from Todds point about the effect of TPS values on ignition advance is that the ecu likely does not advance the ignition as the TPS value increases. Rather, it probably retards the ignition for higher TPS values and advances the ignition based on RPM. That is one of the benefits of electronic controls. In the old days you were lucky to have two aspects control the ignition curve, centrifugal (rpm) and throttle (vacuum). Now you can make it do what ever you want at what ever throttle position and rpm.
Personally I don't think it would have a impact on how the motor ran unless you adjusted the "sacred screw" and then reset the TPS. The TPS value at idle will increase if you adjust the "sacred screw", but it will have no impact on the TPS value at WOT. Adjusting the screw is no different then the fast idle on a V11 or cracking the throttle open until you reset the TPS.
What I gather from Todds point about the effect of TPS values on ignition advance is that the ecu likely does not advance the ignition as the TPS value increases. Rather, it probably retards the ignition for higher TPS values and advances the ignition based on RPM. That is one of the benefits of electronic controls. In the old days you were lucky to have two aspects control the ignition curve, centrifugal (rpm) and throttle (vacuum). Now you can make it do what ever you want at what ever throttle position and rpm.
Spaceclam
Cruisin' Guzzisti
I should have been more clear.
Todd showed me once. We plugged into the vstd, and started the bike, in neutral. As throttle was applied, the engine sped up, under no load, and the value it showed for timing decreased.
Hence, Todd's comment about it retarding the ignition. That's what the VSTD shows but that just doesn't make any sense.
Todd showed me once. We plugged into the vstd, and started the bike, in neutral. As throttle was applied, the engine sped up, under no load, and the value it showed for timing decreased.
Hence, Todd's comment about it retarding the ignition. That's what the VSTD shows but that just doesn't make any sense.
Fair enough. I did not realize you two had a whole 'nother side to this conversation. I think putting a bike on a dyno while hooked up might answer this question.