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Now you just have to wait for the snow to melt.
The plenum brackets look much nicer and go with the look of the bike. Very nice looking package. How's the EFI coming along?
EFI specialist is adjusted it today , but it?s not so easy to get it idling smoothly .
Some of your problem will be as a result of your stock cam overlap. You will be pushing a lot of raw fuel out the exhaust, at and just above idle. You may need to change your cams to supercharge speced ones.
Great project, you'll have it sorted soon.
Some of your problem will be as a result of your stock cam overlap. You will be pushing a lot of raw fuel out the exhaust, at and just above idle. You may need to change your cams to supercharge speced ones.
Great project, you'll have it sorted soon.
Does anybody know , where to buy those by-pass valves (Eaton) ?
http://www.magnusonproducts.com/bypass.htm
Seems like matching a blower to a motor is a little more tricky than originally thought? You will get it figured out soon enough! Good luck!
Yes , it?s a bit more complicated than I think . I?m going to desing and make one special bypass valve , because all aftermarket bypass valves are too big .
I was wondering about this when you started. Would a simple reed valve work. Or, why not just over drive the thing and bleed the pressure on the other end? Not a real clean way to handle it.
A reed valve does not work , because at idle the flowing direction is from pressure side to suction side ( actually there is vacum in both sides but bigger in suction side ) .
In "off cruising speeds" and acceleration valve should to be closed .
If I ever going to build an other supercharged bike , I?m going to put a throttle in pressure side of supercharger .
Sorry about that, went back and reread your original post...
"Between throttlebody and supercharger is more vacum than after supercharger + intake manifold volume is big "
That said I agree on the reed. I was thinking it was backwards for some reason. Can't you underdrive the blower to get a better match? Do you feed both pressures (after throttle plate and blower outlet) to the controller? Seems like if you knew ambient pressure, these two, plate position you could get it to control as is. I was looking over a book I have (very old) that talks a bit about what your trying to do. There is never any mention of trying to balance out the pressures with a bypass. These were very simple systems. No electronics.
Of course they may have ran like total crap as well.
Underdriving the blower does not help , it?s still there .
This is "borrowed" from Corky Bell?s book Supercharged! :
Cruise conditions and other normally aspirated operational modes can suffer from undesired pumping losses .
When cruising about 15 inches of vacuum , the system without bypass valve will create about 20 inches of vacuum between the throttle and blower , because the Roots is pulling from throttle plate . This "boosting" is a constant and unnecessary waste of power and also produces a small amount of heat .
Although the heat is not too harmful , the bypass valve fixes this situation , allowing the Roots (or any other blower mounted after the throttle) to "freewheel" by pumping back into its intake side , balancing the pressure between the manifold and throttlebody .
Bypass is vacuum operated and get its vacuum from intake manifold .
MAP sensor got it?s singnal from intake manifold only .
Only bypass valve can help to get idle more normal . Then I can start with ECU mapping .
Underdriving the blower does not help , it?s still there .
This is "borrowed" from Corky Bell?s book Supercharged! :
Cruise conditions and other normally aspirated operational modes can suffer from undesired pumping losses .
When cruising about 15 inches of vacuum , the system without bypass valve will create about 20 inches of vacuum between the throttle and blower , because the Roots is pulling from throttle plate . This "boosting" is a constant and unnecessary waste of power and also produces a small amount of heat .
Although the heat is not too harmful , the bypass valve fixes this situation , allowing the Roots (or any other blower mounted after the throttle) to "freewheel" by pumping back into its intake side , balancing the pressure between the manifold and throttlebody .
Bypass is vacuum operated and get its vacuum from intake manifold .
MAP sensor got it?s singnal from intake manifold only .
Only bypass valve can help to get idle more normal . Then I can start with ECU mapping .