vics + turbo
#23
Cpt. Slow
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So that's a PWM output, which I've tried on the dyno. Unfortunately you're controlling a electrical solenoid, which responds to the PWM, but it's controlling a vacuum actuator, unlike the VVT oil control valve. So you'd want a large vacuum canister to hold vacuum in order for it to work. According to my dyno testing on a naturally aspirated, VVT equipped car, there would be a benefit, but it would be incredibly minor. After two dyno pulls back to back, we found two cross over points, the stock ~5250 point, and one at ~3500 IIRC, it's been a while. We tried "PWMing" the output, which started to show minimal benefits, but as I said ran out of vacuum. In the end, we set it back to a switched output, active above 3500 and below 5250, or whatever those two RPMs were.
On boost, I've found the VICs feature to still make small power differences, but 5hp on a 130hp engine is a much bigger deal than 5hp on a 300hp engine. I would do two dyno pulls, one with it set to 1000rpm, one at 10000rpm. Find where those two dyno's cross over, set your programmable switched output to that RPM, and forget it.
On boost, I've found the VICs feature to still make small power differences, but 5hp on a 130hp engine is a much bigger deal than 5hp on a 300hp engine. I would do two dyno pulls, one with it set to 1000rpm, one at 10000rpm. Find where those two dyno's cross over, set your programmable switched output to that RPM, and forget it.
#24
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i was going to gun VICS but then thought about the low rpm benefits.
i'm going to follow the advice but electronically open and close, not using vacuum. we'll see how it works
even if 2 hp difference, it seems it is still worth it...
i'm going to follow the advice but electronically open and close, not using vacuum. we'll see how it works
even if 2 hp difference, it seems it is still worth it...
So that's a PWM output, which I've tried on the dyno. Unfortunately you're controlling a electrical solenoid, which responds to the PWM, but it's controlling a vacuum actuator, unlike the VVT oil control valve. So you'd want a large vacuum canister to hold vacuum in order for it to work. According to my dyno testing on a naturally aspirated, VVT equipped car, there would be a benefit, but it would be incredibly minor. After two dyno pulls back to back, we found two cross over points, the stock ~5250 point, and one at ~3500 IIRC, it's been a while. We tried "PWMing" the output, which started to show minimal benefits, but as I said ran out of vacuum. In the end, we set it back to a switched output, active above 3500 and below 5250, or whatever those two RPMs were.
On boost, I've found the VICs feature to still make small power differences, but 5hp on a 130hp engine is a much bigger deal than 5hp on a 300hp engine. I would do two dyno pulls, one with it set to 1000rpm, one at 10000rpm. Find where those two dyno's cross over, set your programmable switched output to that RPM, and forget it.
On boost, I've found the VICs feature to still make small power differences, but 5hp on a 130hp engine is a much bigger deal than 5hp on a 300hp engine. I would do two dyno pulls, one with it set to 1000rpm, one at 10000rpm. Find where those two dyno's cross over, set your programmable switched output to that RPM, and forget it.
#27
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Possibly less than nothing. Isn't vics just providing additional plenum volume with the butterflies open? I don't think half open butterflies are going to effectively allow for half the volume increase. It may create some other strangeness in flow that could be beneficial though. I guess curlys findings are encouraging.
Do the thing and post the data please.
Do the thing and post the data please.
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