MINI2

Peewee12 · May 20th, 2008, 06:51 PM

Hi

I am new to the world of mini's and superchargers having just bought a mcs, I am just wanting to know what the bypass valve does and how up rated units help.

Thanks
Peewee

MINI-Morgan · May 20th, 2008, 07:21 PM

It bypasses the Supercharger otherwise you'd be on boost all the time.

Uprated? maybe a stronger spring but that would just make it come on all of a sudden.

Just make sure yours closes properly and thats about the best you can hope for

dukesantos · May 20th, 2008, 07:33 PM

There may be a bit of confusion here, the 2002-2006 MCS has a belt driven, geared supercharger. You can increase the power by changing the pulley to increase the rpm it turns at. It is always on. The new MCS is turbocharged and probably has a bypass valve, I'm not as familiar with that engine.

toydestroy · May 20th, 2008, 08:26 PM

Quote: Originally Posted by dukesantos (original)

There may be a bit of confusion here, the 2002-2006 MCS has a belt driven, geared supercharger. You can increase the power by changing the pulley to increase the rpm it turns at. It is always on. The new MCS is turbocharged and probably has a bypass valve, I'm not as familiar with that engine.

02/06 Mini does have a bypass valve.

Basically helps keep the boost levels up when your at low revs and other bits and bobs to do with vacuum pressures either side of the turbines.

DaFlake · May 20th, 2008, 09:00 PM

They are correct Duke, there is a bypass valve in the 02 - 06. You are thinking of a blow off valve.

An uprated BPV will have a stronger spring for faster response and fully close. I uprated mine and it does provide for better throttle response and faster delivery of boost. I like it but many others do not It is more of a preference thing.

brainycheddar · May 21st, 2008, 03:43 AM

when you're buying an uprated bypass valve, usually the manufacturer will check to see if the valve closes completely, thus providing the maximum available boost when it's supposed to. the second thing that will often be done is to add a stiffer spring to make maximum boost more of the time. I'd say 90% of the time, you are being overcharged for the amount of modification being done, and the only real gain in performance is if the valve didn't close completely beforehand.

dukesantos · May 21st, 2008, 07:08 AM

Thanks for the info, I was thinking of the blow off valve on the turbo.

DaFlake · May 21st, 2008, 07:17 AM

Quote: Originally Posted by dukesantos (original)

Thanks for the info, I was thinking of the blow off valve on the turbo.

No worries.... I used to get the two confused myself.

Paul Webster · May 21st, 2008, 07:59 AM

Dont forget that you could have a 07 /08 cab and still be supercharged

Peewee12 · May 28th, 2008, 12:52 PM

does anyone have one of these

New Mini Product | Alta Tuned By-Pass Valve

DaFlake · May 28th, 2008, 01:00 PM

I don't have the Alta, but I do have the Detroit Tuned one.

Detroit Tuned // Detroit Tuned Bypass Valve

It was a nice addition to the MINI but at first it was a bit jerky in response. Now that the spring has settled in, it is very smooth. Also, the one you posted looks rather expensive. A bypass valve from the dealer was 60 Euro here in Germany.

MINIMANIAUK · May 28th, 2008, 02:23 PM

Just for a bit of clarification;

The supercharger is a pump ,at one end it pumps into the engine and at the other it sucks air in
The air is sucked in through the throttle plate and pumped into the engine intake,if it pumps more air in than the engine can take it produces a pressure (boost pressure).
If the throttle is open all is well except you would not be able top slow down! so the throttle is closed -the charger is still turning and still pumping ,but the pump cannot suck as much as the throttle is closed.
the charger now has to work harder trying to suck air in -it creates a vacuum it is sucking so hard! and the extra work the pump/charger is doing creates heat-lots of it This heat is added to the air coming in and there is a lot less volume of that air (the throttle is closed)
To offset this the Bypass valve is fitted ,it is a recirculation valve -it connects the output air to the intake air and reduces the suction losses by satisfying the charger input air demand.
there is still some heat added to the boost air but it is minimised.
the valve opens/closes when it senses the throttle closed -by vacuum pressure and if it does not full close(Spring pressure) then boost pressure is lost as it is being recirculated.
due to the heating of air when the valve is opened -on throttle opening again a small amount of extra fuel is commanded to prevent lean conditions (yet another thing to take on board with very small pully fitment)
dont know if this helps any?

DaFlake · May 28th, 2008, 02:25 PM

So basically it just sucks...

Sorry, I couldn't resist.

MINIMANIAUK · May 28th, 2008, 02:36 PM

Like a 2 dollar wh....

Its always easier to explain in laymans terms,and clear up misconceptions like boost pressure is constant -its not

M4 CUS · May 28th, 2008, 06:15 PM

so is there a big benefit in fitting one? performance gains?

ScottyBoy · May 28th, 2008, 06:26 PM

Quote: Originally Posted by M4 CUS (original)

so is there a big benefit in fitting one? performance gains?

Nope not big, there is minor benefits mate, i adjusted mine and it was slightly better nothing to scream about in the performance department.

Not that my car is were it should be anyway hey

DaFlake · May 28th, 2008, 06:34 PM

A little quicker throttle response. That was about it.... I don't really recommend it.

M4 CUS · May 28th, 2008, 07:10 PM

Quote: Originally Posted by ScottyBoy (original)

Nope not big, there is minor benefits mate, i adjusted mine and it was slightly better nothing to scream about in the performance department.

Not that my car is were it should be anyway hey

Didn't realise you had one scotty. yep think there is some big time up with urs. are u goin to 1320's on friday to sort it?

ScottyBoy · May 28th, 2008, 07:15 PM

Quote: Originally Posted by M4 CUS (original)

Didn't realise you had one scotty. yep think there is some big time up with urs. are u goin to 1320's on friday to sort it?

I dont have an uprated one but i have adjusted it so its fully closed when should be.

Ive been, i took the day off work yesterday and went down, All is fine with the car so it must be the mods that i have.

When i get chance the M7 AGS is coming off and stock filter is going back on, and im going for a Milltek and De-Cat.

GARY GP · May 28th, 2008, 07:45 PM

Quote: Originally Posted by ScottyBoy (original)

I dont have an uprated one but i have adjusted it so its fully closed when should be.

Ive been, i took the day off work yesterday and went down, All is fine with the car so it must be the mods that i have.

When i get chance the M7 AGS is coming off and stock filter is going back on, and im going for a Milltek and De-Cat.

And a large box of aspirin!!..

May 20th, 2008, 06:51 PM	#1
Peewee12 MINI2 Newbie Join Date: Apr 2008 Location: Rotherham Local Time: 10:10 PM Posts: 12 Offline	Bypass Valve ? Hi I am new to the world of mini's and superchargers having just bought a mcs, I am just wanting to know what the bypass valve does and how up rated units help. Thanks Peewee

May 20th, 2008, 07:21 PM	#2 (permalink)
MINI-Morgan MINI Obsessed... My Classifieds Join Date: Nov 2003 Location: Southampton, Hants Local Time: 09:10 PM Posts: 4,679 Offline	It bypasses the Supercharger otherwise you'd be on boost all the time. Uprated? maybe a stronger spring but that would just make it come on all of a sudden. Just make sure yours closes properly and thats about the best you can hope for One Man, One Project......find out what happens next at MINIProject.co.uk For MINIs in the south it can only be South Coast New MINI Club

May 20th, 2008, 09:00 PM	#5 (permalink)
DaFlake Lovin' every MINI of it! Join Date: Oct 2005 Location: Hanging on The Cape! Local Time: 04:10 PM Posts: 11,037 Offline	They are correct Duke, there is a bypass valve in the 02 - 06. You are thinking of a blow off valve. An uprated BPV will have a stronger spring for faster response and fully close. I uprated mine and it does provide for better throttle response and faster delivery of boost. I like it but many others do not It is more of a preference thing. Global Moderator

May 21st, 2008, 03:43 AM	#6 (permalink)
brainycheddar a.k.a. BrainRush Join Date: Oct 2006 Location: NorCal Local Time: 01:10 PM Posts: 101 Offline	when you're buying an uprated bypass valve, usually the manufacturer will check to see if the valve closes completely, thus providing the maximum available boost when it's supposed to. the second thing that will often be done is to add a stiffer spring to make maximum boost more of the time. I'd say 90% of the time, you are being overcharged for the amount of modification being done, and the only real gain in performance is if the valve didn't close completely beforehand. Mods:

May 21st, 2008, 07:17 AM	#8 (permalink)
DaFlake Lovin' every MINI of it! Join Date: Oct 2005 Location: Hanging on The Cape! Local Time: 04:10 PM Posts: 11,037 Offline	Quote: Originally Posted by dukesantos (original) Thanks for the info, I was thinking of the blow off valve on the turbo. No worries.... I used to get the two confused myself. Global Moderator

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May 20th, 2008, 07:33 PM	#3 (permalink)
dukesantos Moderator Join Date: Apr 2002 Location: Viva Las Vegas Local Time: 01:10 PM Posts: 707 Offline	There may be a bit of confusion here, the 2002-2006 MCS has a belt driven, geared supercharger. You can increase the power by changing the pulley to increase the rpm it turns at. It is always on. The new MCS is turbocharged and probably has a bypass valve, I'm not as familiar with that engine.

May 20th, 2008, 08:26 PM	#4 (permalink)
toydestroy MINI2 Newbie Join Date: Apr 2006 Local Time: 10:10 PM Posts: 26 Offline	Quote: Originally Posted by dukesantos (original) There may be a bit of confusion here, the 2002-2006 MCS has a belt driven, geared supercharger. You can increase the power by changing the pulley to increase the rpm it turns at. It is always on. The new MCS is turbocharged and probably has a bypass valve, I'm not as familiar with that engine. 02/06 Mini does have a bypass valve. Basically helps keep the boost levels up when your at low revs and other bits and bobs to do with vacuum pressures either side of the turbines.

May 21st, 2008, 07:08 AM	#7 (permalink)
dukesantos Moderator Join Date: Apr 2002 Location: Viva Las Vegas Local Time: 01:10 PM Posts: 707 Offline	Thanks for the info, I was thinking of the blow off valve on the turbo.

May 21st, 2008, 07:59 AM	#9 (permalink)
Paul Webster MINI2 Master Join Date: Jul 2005 Location: Beds Cambs Northants Local Time: 09:10 PM Posts: 1,956 Offline	Dont forget that you could have a 07 /08 cab and still be supercharged Slicks 11.77@115.92mph Street tyres 12.162 @ 119.02 It's not how much you spend but how well you spend it

May 28th, 2008, 12:52 PM	#10 (permalink)
Peewee12 MINI2 Newbie Join Date: Apr 2008 Location: Rotherham Local Time: 10:10 PM Posts: 12 Offline	does anyone have one of these New Mini Product \| Alta Tuned By-Pass Valve

May 28th, 2008, 01:00 PM	#11 (permalink)
DaFlake Lovin' every MINI of it! Join Date: Oct 2005 Location: Hanging on The Cape! Local Time: 04:10 PM Posts: 11,037 Offline	I don't have the Alta, but I do have the Detroit Tuned one. Detroit Tuned // Detroit Tuned Bypass Valve It was a nice addition to the MINI but at first it was a bit jerky in response. Now that the spring has settled in, it is very smooth. Also, the one you posted looks rather expensive. A bypass valve from the dealer was 60 Euro here in Germany. Global Moderator

May 28th, 2008, 02:23 PM	#12 (permalink)
MINIMANIAUK MINI2 Sponsor Join Date: Mar 2006 Local Time: 09:10 PM Posts: 1,080 Offline	Just for a bit of clarification; The supercharger is a pump ,at one end it pumps into the engine and at the other it sucks air in The air is sucked in through the throttle plate and pumped into the engine intake,if it pumps more air in than the engine can take it produces a pressure (boost pressure). If the throttle is open all is well except you would not be able top slow down! so the throttle is closed -the charger is still turning and still pumping ,but the pump cannot suck as much as the throttle is closed. the charger now has to work harder trying to suck air in -it creates a vacuum it is sucking so hard! and the extra work the pump/charger is doing creates heat-lots of it This heat is added to the air coming in and there is a lot less volume of that air (the throttle is closed) To offset this the Bypass valve is fitted ,it is a recirculation valve -it connects the output air to the intake air and reduces the suction losses by satisfying the charger input air demand. there is still some heat added to the boost air but it is minimised. the valve opens/closes when it senses the throttle closed -by vacuum pressure and if it does not full close(Spring pressure) then boost pressure is lost as it is being recirculated. due to the heating of air when the valve is opened -on throttle opening again a small amount of extra fuel is commanded to prevent lean conditions (yet another thing to take on board with very small pully fitment) dont know if this helps any? www.minimaniauk.com

May 28th, 2008, 02:25 PM	#13 (permalink)
DaFlake Lovin' every MINI of it! Join Date: Oct 2005 Location: Hanging on The Cape! Local Time: 04:10 PM Posts: 11,037 Offline	So basically it just sucks... Sorry, I couldn't resist. Global Moderator

May 28th, 2008, 02:36 PM	#14 (permalink)
MINIMANIAUK MINI2 Sponsor Join Date: Mar 2006 Local Time: 09:10 PM Posts: 1,080 Offline	Like a 2 dollar wh.... Its always easier to explain in laymans terms,and clear up misconceptions like boost pressure is constant -its not www.minimaniauk.com

May 28th, 2008, 06:15 PM	#15 (permalink)
M4 CUS MINI2 Regular Join Date: Aug 2007 Local Time: 10:10 PM Posts: 58 Offline	so is there a big benefit in fitting one? performance gains?

May 28th, 2008, 06:26 PM	#16 (permalink)
ScottyBoy Obsessive Car Cleaner OCC My Classifieds Join Date: Jul 2006 Location: Thornaby NE Local Time: 09:10 PM Posts: 2,951 Online	Quote: Originally Posted by M4 CUS (original) so is there a big benefit in fitting one? performance gains? Nope not big, there is minor benefits mate, i adjusted mine and it was slightly better nothing to scream about in the performance department. Not that my car is were it should be anyway hey

May 28th, 2008, 06:34 PM	#17 (permalink)
DaFlake Lovin' every MINI of it! Join Date: Oct 2005 Location: Hanging on The Cape! Local Time: 04:10 PM Posts: 11,037 Offline	A little quicker throttle response. That was about it.... I don't really recommend it. Global Moderator

May 28th, 2008, 07:10 PM	#18 (permalink)
M4 CUS MINI2 Regular Join Date: Aug 2007 Local Time: 10:10 PM Posts: 58 Offline	Quote: Originally Posted by ScottyBoy (original) Nope not big, there is minor benefits mate, i adjusted mine and it was slightly better nothing to scream about in the performance department. Not that my car is were it should be anyway hey Didn't realise you had one scotty. yep think there is some big time up with urs. are u goin to 1320's on friday to sort it?

May 28th, 2008, 07:15 PM	#19 (permalink)
ScottyBoy Obsessive Car Cleaner OCC My Classifieds Join Date: Jul 2006 Location: Thornaby NE Local Time: 09:10 PM Posts: 2,951 Online	Quote: Originally Posted by M4 CUS (original) Didn't realise you had one scotty. yep think there is some big time up with urs. are u goin to 1320's on friday to sort it? I dont have an uprated one but i have adjusted it so its fully closed when should be. Ive been, i took the day off work yesterday and went down, All is fine with the car so it must be the mods that i have. When i get chance the M7 AGS is coming off and stock filter is going back on, and im going for a Milltek and De-Cat.

May 28th, 2008, 07:45 PM	#20 (permalink)
GARY GP GP-1528 My Classifieds Join Date: Jun 2005 Local Time: 09:10 PM Posts: 800 Offline	Quote: Originally Posted by ScottyBoy (original) I dont have an uprated one but i have adjusted it so its fully closed when should be. Ive been, i took the day off work yesterday and went down, All is fine with the car so it must be the mods that i have. When i get chance the M7 AGS is coming off and stock filter is going back on, and im going for a Milltek and De-Cat. And a large box of aspirin!!..

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