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I'm plumbing my boost controller solenoids and planned on just using the compressor cover for a source. I really don't wanna put a co2 tank in the car unless the compressor will be unreliable. So will this work okay?
Yes, if I understand your question correctly. The transducer reading goes hand in hand with the duty cycle of your solenoid to give you your desired boost. I'm guessing the transducer is in the dome of the gate? If yes, then it's reading how much pressure you're putting on top of the gate (Into the dome) to get to the boost level you're at.
Depending on what strategy you use, you may not need a transducer. If you use open-loop duty cycle method, no sensor is needed. Any other strategy (dome pressure, map based) need the sensor. I don't use one.
Depending on what strategy you use, you may not need a transducer. If you use open-loop duty cycle method, no sensor is needed. Any other strategy (dome pressure, map based) need the sensor. I don't use one.
I thought you had to use a dome sensor with the Holley control
I always forget the open loop strategy. No sensor is needed if OL, it's basically up to you to decide if you want more or less duty cycle to achieve your desired boost levels. No transducer is needed for that.
The easiest way is use the "open-loop, duty cycle" method, and start with 0% DC and work your way up till you get the boost you want. No dome sensor needed, use 1 or 2 solenoids. Easy peasy. I use 1 solenoid. This method however is not as robust as the other strategies. It operates much like a regular boost controller in terms of the quality of the control. The other methods are more of a closed-loop system in where the system will correct itself to maintain target boost. But there is some trial and error and a bit of a learning curve. I would actually like to do that eventually, but the dam thing works so good right now it will probably just stay that way. Right now if I set my controls to give me 17psi, I actually get 15psi in 1st, 16 in 2nd, and the 17psi in high. Just like my cheapo manual controller operated. There's no correction from the ecu, so what you type in is what you get. The other methods would maintain target boost better, but for what I do it's more than adequate and super easy to change boost settings with the laptop or the little digital display. I do see some fluctuations in psi I think from summer to winter. The other methods I'm sure would eliminate that, but again for what I do...it's fine.
It may be a Holley problem...but there is no reason full closed loop control cannot be done with 1 or 2 ( or more ) solenoids and with whatever type of air you want, in any plumbing configuration you want
As for a dome sensor...that really is an odd one too, as dome pressure really has little relevance to manifold pressure, although perhaps from a diagnostic point of view it could be handy to know
Dome sensor works great. As stated earlier it gives excellent resolution and control. Also it is a great way to monitor/test back pressure. For the extra $50 in solonoid/transducer it is well worth it IMO.
I wonder if he ran a 4 port solenoid and reworked the table if he could get a consistent psi in all gears. Seems he'd be able to add to the dome and take away from the bottom at the same time to achieve his arget boost levels.
Dome sensor works great. As stated earlier it gives excellent resolution and control. Also it is a great way to monitor/test back pressure. For the extra $50 in solonoid/transducer it is well worth it IMO.
The only way to monitor/test backpressure....is to monitor and test backpressure.
The only way to monitor/test backpressure....is to monitor and test backpressure.
Dome pressure does not tell you backpressure
Wrong. It's a rudimentary way of monitoring BP. The amount of pressure you have to keep on the dome in correlation with the spring rate is a direct reflection of BP. Will it give you exact ratios? No. But it is a great reference if you don't have a proper gauge hooked up.
I've personally verified it with a BP gauge on both my car and a friends TT C6. If I wanted 15psi boost pressure it would take right at 15psi of dome pressure. This ratio held true up until about 26lbs of boost pressure and then it required around 30-31psi of done pressure. For his car it took nearly 30psi to maintain 15lbs of boost. Both cars with 6lb springs. I bet you can quess what our BP ratio were.
Wrong. It's a rudimentary way of monitoring BP. The amount of pressure you have to keep on the dome in correlation with the spring rate is a direct reflection of BP. Will it give you exact ratios? No. But it is a great reference if you don't have a proper gauge hooked up.
I've personally verified it with a BP gauge on both my car and a friends TT C6. If I wanted 15psi boost pressure it would take right at 15psi of dome pressure. This ratio held true up until about 26lbs of boost pressure and then it required around 30-31psi of done pressure. For his car it took nearly 30psi to maintain 15lbs of boost. Both cars with 6lb springs. I bet you can quess what our BP ratio were.
very very very rudimentary.
There are various issues that could affect how much you apply to the top.....yet nothing to do with backpressure.
08-22-2016, 10:37 AM
Holley boost control-co2 or compressor air? 
