Twin screw with BOV (no trolls or dumb asses)
#1
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Twin screw with BOV (no trolls or dumb asses)
Going to try to have a real supercharger post for once and looking for input from the local engineers and smart people.
problem and back ground:
mp62 on my car does not have the response i would like. the lower the rpm the worse. if i'm at idle (1k) and stomp on the peddle i can watch the boost gauge, it goes from ~40kpa to 100kpa and sits there for about a sec and the car sounds like it's about to die then boom boost starts to build. if the car is at a higher rpm it does the same thing but boost kicks in faster but still to slow.
why this happens:
throttle body is on the back of the blower so when it's cracked open it take time for air to get form there to the intake and pressurize the fmic and pipes.
looking for how to get the best results, don't want to disable the bypass valve and just install a bov with the thottle body back on the intake as that would make the blower at 11psi when ever to car is running making a lot of heat and ware on the car, enough to end it's life way sooner then it should.
problem and back ground:
mp62 on my car does not have the response i would like. the lower the rpm the worse. if i'm at idle (1k) and stomp on the peddle i can watch the boost gauge, it goes from ~40kpa to 100kpa and sits there for about a sec and the car sounds like it's about to die then boom boost starts to build. if the car is at a higher rpm it does the same thing but boost kicks in faster but still to slow.
why this happens:
throttle body is on the back of the blower so when it's cracked open it take time for air to get form there to the intake and pressurize the fmic and pipes.
looking for how to get the best results, don't want to disable the bypass valve and just install a bov with the thottle body back on the intake as that would make the blower at 11psi when ever to car is running making a lot of heat and ware on the car, enough to end it's life way sooner then it should.
#3
looking for how to get the best results, don't want to disable the bypass valve and just install a bov with the thottle body back on the intake as that would make the blower at 11psi when ever to car is running making a lot of heat and wear on the car, enough to end it's life way sooner then it should.
#4
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most turbo cars have better thottle response because they are always pushing air towards the intake so there is always so volume of air in the pipes. on y set up there is a lot less because the bypass is keeping the air out of the blower making boost lag and slower throttle response.
#7
The bypass works fine on turbo cars since you're just relieving the diminishing volume of compressed air when the throttle plate closes. If you close the throttle plate at 6krpm with an MP62 and a standard bypass valve, it's a recipe for blowing **** apart.
#8
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my first thought was leave the bypass but run the vac line to the intake side instead of off the blower and adjust or make it so it never 100% closes (or opens, which ever is the one that keeps the psi from building), replace tb to intake side and add a bov.
so now you have a bov letting the air you don't need out, the blower is pushing enough air to keep a good amount of presser in the fmic to charge the pipes and get air in the motor the sec i hit the gas and the bypass mod let the blower not get over worked and wont cut air completely anymore.
#10
I personally haven't looked at the pump curves or bov relief rates, but I'd imagine you could get that information pretty easy. It shouldn't take much work to size everything up for that setup. The supercharger whine really isn't bad, but relieving all that air to atmosphere gets annoying to the point you just want to mash the throttle all the time.
I don't know what you're running for computer, but this is where the benefits of not metering that air come into play.
WonTon, I believe that's what we're discussing...
I don't know what you're running for computer, but this is where the benefits of not metering that air come into play.
WonTon, I believe that's what we're discussing...
#11
I wouldn't knock duals (one extra moving part...that I think even a race car driver could mechanically handle) without reading some of the threads. They should give back pretty much the stock throttle response since you have the preblower TB cracked feeding the intake tubing (IC, piping) so that the stock TB has air to munch when it opens. When I dynoed my base hotside SC car (no IC, so minimal throttle volume) there was a car with the setup and IC. The dyno operator noted better response with the duals and IC over my stock hotside. So take is as you want (I don't know the scale for your epic cool meter).
#13
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car will still have 1 sec of boost lag when it goes from vac to 0psi, sits there then jumps to 5 psi.
#15
Try the duals, you'll like it.
Go 3" on the MP62 inlet.
How much boost are you running? (Me=only 6psi)
I have no BOV and no restrictor in the bypass allowing it fast response and the overpressure blows back through the bypass past the cracked open throttle.
Throttle response is back to stock - I had to relearn shifting on the car after getting lazy with the (slight) boost lag.
Go 3" on the MP62 inlet.
How much boost are you running? (Me=only 6psi)
I have no BOV and no restrictor in the bypass allowing it fast response and the overpressure blows back through the bypass past the cracked open throttle.
Throttle response is back to stock - I had to relearn shifting on the car after getting lazy with the (slight) boost lag.
#16
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Try the duals, you'll like it.
Go 3" on the MP62 inlet.
How much boost are you running? (Me=only 6psi)
I have no BOV and no restrictor in the bypass allowing it fast response and the overpressure blows back through the bypass past the cracked open throttle.
Throttle response is back to stock - I had to relearn shifting on the car after getting lazy with the (slight) boost lag.
Go 3" on the MP62 inlet.
How much boost are you running? (Me=only 6psi)
I have no BOV and no restrictor in the bypass allowing it fast response and the overpressure blows back through the bypass past the cracked open throttle.
Throttle response is back to stock - I had to relearn shifting on the car after getting lazy with the (slight) boost lag.
#19
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most turbo cars have better thottle response because they are always pushing air towards the intake so there is always so volume of air in the pipes. on y set up there is a lot less because the bypass is keeping the air out of the blower making boost lag and slower throttle response.
I have a Bosch BOV you can have...and I think the single t-body w/a TiAL Q is the most simple to build and maintain. It is the way. Your car is loud enough that you won't notice it...unless it produces the "Brown Note."