Hondata do you have any tips for setting up boost control duty cycles?
I've noticed that in lower gears you need to have higher BC duty cycles to achieve the same boost in 3rd or 4th gears. i.e. 35% duty cycle gave me 9 psi in 2nd gear and around 16psi in 4th.
Does the frequency have anything to do with this? I don't know what would happen if I changed it to 10. I currently have it set at 50.
Also is the temperature compensation tables for boost control for Intake air temp or outside ambient temperature?
Would you have a baseline compensation table that I could go off of? I was just simply going to try a percentage so once I have my BC duty cycles established for say 80 degrees I would calculate the percentage difference of temperture and apply that same percentage to the BC duty cycles. i.e. if its 40 degrees outside then that is 50% colder than 80 degrees so I would cut my duty cycle in half.
But if the temp compensation tables are for IAT temps then my idea wont work. I don't know what the span of IAT are.
Tip for boost control duty cycles and temp. compensation
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ajpturbopittsburgh
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- Joined: Wed May 26, 2010 10:58 am
The frequency is basically solenoid speed. for setting lower boost levels I found that 20Hz works best and gives you more control when you want to increase boost by smaller amounts. But you will have to use much more duty to make higher boost levels especially in 3rd gear. At the moment I'm running 50Hz because I'm running much higher boost levels than before. I'm running 17psi on a 7psi spring. The stiffer the spring the lower it likes the frequency. There is no real exact science to it. It's basically trial and error.
The temp comp is based on IAT. And you would only need to trim by a few percent. It's not as deep as you are making it. I have my duty increasing by 1% every 10 degrees or so and decreasing the same way. It's mostly trial and error. Just when the temps change run the live tuning and play with it. It's the only real way to dial in your boost perfectly.
The temp comp is based on IAT. And you would only need to trim by a few percent. It's not as deep as you are making it. I have my duty increasing by 1% every 10 degrees or so and decreasing the same way. It's mostly trial and error. Just when the temps change run the live tuning and play with it. It's the only real way to dial in your boost perfectly.
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ajpturbopittsburgh
- Posts: 145
- Joined: Wed May 26, 2010 10:58 am
Couple questions then. I have a 4.35psi small red tial spring. I got up to 19.5 psi during my tuning I was using a manual boost controller for tuning. What would 100% duty cycle give me? I thought you could only go about triple your wastegate spring?
If I want to use my manifold vaccuum instead of the compressor outlet should I cap off the compressor outlet and run a vacuum line from the manifold with a tee and one side go to the bottom of my wastegate and the other to port 1 of the solenoid and then a vac line from port 2 to the top of wastegate OR leave my vac line from the compressor outlet to the bottom of the wastegate and run a vac line from manifold to port 1 and then a vac line from port 2 to the top of wastegate?
Currently I run a vac line from compressor outlet with a tee and one side goes to bottom of wastegate and the other to port 1 and then a vac line from port 2 to the top of wastegate.
If I want to use my manifold vaccuum instead of the compressor outlet should I cap off the compressor outlet and run a vacuum line from the manifold with a tee and one side go to the bottom of my wastegate and the other to port 1 of the solenoid and then a vac line from port 2 to the top of wastegate OR leave my vac line from the compressor outlet to the bottom of the wastegate and run a vac line from manifold to port 1 and then a vac line from port 2 to the top of wastegate?
Currently I run a vac line from compressor outlet with a tee and one side goes to bottom of wastegate and the other to port 1 and then a vac line from port 2 to the top of wastegate.
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ajpturbopittsburgh
- Posts: 145
- Joined: Wed May 26, 2010 10:58 am
You really don't want to use the IM for any boost reference for an external gate. They should never see vacuum. The vacuum causes the diaphragm to get pulled into the banjo bolt or any other type adapter and wear a hole in your diaphragm.ajpturbopittsburgh wrote:Couple questions then. I have a 4.35psi small red tial spring. I got up to 19.5 psi during my tuning I was using a manual boost controller for tuning. What would 100% duty cycle give me? I thought you could only go about triple your wastegate spring?
If I want to use my manifold vaccuum instead of the compressor outlet should I cap off the compressor outlet and run a vacuum line from the manifold with a tee and one side go to the bottom of my wastegate and the other to port 1 of the solenoid and then a vac line from port 2 to the top of wastegate OR leave my vac line from the compressor outlet to the bottom of the wastegate and run a vac line from manifold to port 1 and then a vac line from port 2 to the top of wastegate?
Currently I run a vac line from compressor outlet with a tee and one side goes to bottom of wastegate and the other to port 1 and then a vac line from port 2 to the top of wastegate.
And you can run up to as much boost as the gate will hold. The unwritten rule is usually 2-3 times your gate depending on the amount of backpressure there is pushing against the gates piston. The type of manifold used and its flow capabilities will aid in this.
And I have no idea how much boost 100% duty will produce. I could be wrong but I thought Hondata recommends no more than 85% duty with their solenoid and the boost control system.