Fordmods Logo

BOV for supercharger 

 

Page 1 of 2 [ 22 posts ] Go to page 1, 2  Next

 
 Post subject: BOV for supercharger
Posted: Mon Jul 30, 2007 12:43 am 
Smokin em up
Offline
User avatar

Age: 32

Posts: 280

Joined: 22nd Jan 2006

Ride: XB

Location: Hobart
TAS, Australia

Gday,

I will be running a centrifugal supercharger at around 8psi. I am after a BOV or bypass valve to suit. Does anyone know of a good one?

I have found a Bosch unit but it looks like it is made of plastic and I have heard that it may leak boost.

Cheers,

Matt

 

_________________

76XBGS, 383c, custom crow cam, 4V p&p heads, Isky SS Valve+springs, extractors, 2.5"twins, MSD Ignition, Edelbrock intake, Forged bottom end, Barry Grant 750DP, thermo, discs, toploader, Holley fuel pump, SUPERCHARGED!

Top
 Profile  
 
 
Posted: Mon Jul 30, 2007 8:56 am 
Getting Side Ways
Offline
User avatar

Age: 31

Posts: 11103

Joined: 15th Nov 2004

Ride: AU III XR8 Pursuit 250 ute

Location: Hobart
TAS, Australia

The Bosch ones are fine - they're what CAPA use. AFAIK they are also what come on the XR6T and Audis and some other cars too!

Benny said you got a Powerdyne unit.
Go see him at work and get one of the little silver Monza ones - should be fine and decent price.

 

_________________

Heaps of performance EF/L parts for sale, including supercharged VCT motor!

2002 Ford AU Series III Falcon XR8 Pursuit 250 ute - 5.6L of V8 Windsor!

Top
 Profile  
 
 
Posted: Tue Jul 31, 2007 9:32 pm 
Smokin em up
Offline
User avatar

Age: 32

Posts: 280

Joined: 22nd Jan 2006

Ride: XB

Location: Hobart
TAS, Australia

Thanks mate. I went into see Benny today and we couldnt find anything but turbo BOVs. Im after a proper supercharger one as the belt driven powerdyne doesnt like the pulsation of a turbo BOV. I'll just pick up one of the bosch units, wont be running that much through it anyway.

 

_________________

76XBGS, 383c, custom crow cam, 4V p&p heads, Isky SS Valve+springs, extractors, 2.5"twins, MSD Ignition, Edelbrock intake, Forged bottom end, Barry Grant 750DP, thermo, discs, toploader, Holley fuel pump, SUPERCHARGED!

Top
 Profile  
 
 
Posted: Wed Aug 01, 2007 11:44 am 
Getting Side Ways
Offline
User avatar

Age: 31

Posts: 11103

Joined: 15th Nov 2004

Ride: AU III XR8 Pursuit 250 ute

Location: Hobart
TAS, Australia

Mac Winter 76XB351GS wrote:
Thanks mate. I went into see Benny today and we couldnt find anything but turbo BOVs. Im after a proper supercharger one as the belt driven powerdyne doesnt like the pulsation of a turbo BOV. I'll just pick up one of the bosch units, wont be running that much through it anyway.


I'm pretty sure there's no difference. Think about it - a BOV is just a vent wtih a spring holding it closed. The boost pushes it up and the pressure escapes, when there's no more pressure to hold it open it s**t.
The Bosch ones that Capa send with there kits are identical as I said above to that factory fitted to many turbo cars - so Capa and the car manufacturers don't see a difference between them either...
As said above, try one of the little silver Monza units - about the same price as a Bosch one, but the body is mental so they look nicer...

 

_________________

Heaps of performance EF/L parts for sale, including supercharged VCT motor!

2002 Ford AU Series III Falcon XR8 Pursuit 250 ute - 5.6L of V8 Windsor!

Top
 Profile  
 
 
Posted: Wed Aug 01, 2007 9:43 pm 
Smokin em up
Offline
User avatar

Age: 32

Posts: 280

Joined: 22nd Jan 2006

Ride: XB

Location: Hobart
TAS, Australia

I was under the impression that a turbo BOV was designed to "flutter" keep some backpressure on the impeller, where as a supercharger one was designed to stay open untill the excess pressure is released.

I have heard that any "flutter" will give the internal belt a thrashing and kill it fairly quick.

 

_________________

76XBGS, 383c, custom crow cam, 4V p&p heads, Isky SS Valve+springs, extractors, 2.5"twins, MSD Ignition, Edelbrock intake, Forged bottom end, Barry Grant 750DP, thermo, discs, toploader, Holley fuel pump, SUPERCHARGED!

Top
 Profile  
 
 
Posted: Wed Aug 01, 2007 10:14 pm 
Getting Side Ways
Offline
User avatar

Age: 31

Posts: 11103

Joined: 15th Nov 2004

Ride: AU III XR8 Pursuit 250 ute

Location: Hobart
TAS, Australia

Mac Winter 76XB351GS wrote:
I have heard that any "flutter" will give the internal belt a thrashing and kill it fairly quick.


Internal belt? As in inside the supercharger?
Powerdynes are geared inside.
I've never heard of two different kinds of BOV and couldn't find anything about that on the net.
As I said above BOVs are very simple, just a spring holding a peice in place really...

 

_________________

Heaps of performance EF/L parts for sale, including supercharged VCT motor!

2002 Ford AU Series III Falcon XR8 Pursuit 250 ute - 5.6L of V8 Windsor!

Top
 Profile  
 
 
Posted: Thu Aug 02, 2007 11:16 am 
Stock as a Rock
Offline

Posts: 170

Joined: 10th Nov 2005

Location: Canberra
ACT, Australia

well you have bypass valves and Blow off valves, they are very similar but do different things, typically you'd use a bypass valve with a blower, so that it will vent the presure at idle taking the load off the blower.

the bosch BOV's have three different types.

you will need at least 2 of them.

 

_________________

http://www.TURBO351.com

2V 351T, 732rwhp@15psi on LPG.

Top
 Profile  
 
 
Posted: Thu Aug 02, 2007 11:26 am 
Getting Side Ways
Offline

Age: 36

Posts: 9453

Joined: 9th Nov 2004

Gallery: 4 images

Ride: Fordrunner 5.0 Turbo

Location: Wollongong
NSW, Australia

bypass valves are only for positive displacement blowers that run as suck through throttle setups such as the eaton M series blowers.
Top
 Profile  
 
 
Posted: Thu Aug 02, 2007 12:53 pm 
Getting Side Ways
Offline
User avatar

Age: 31

Posts: 11103

Joined: 15th Nov 2004

Ride: AU III XR8 Pursuit 250 ute

Location: Hobart
TAS, Australia

My bad they are belt driven internally.

Image

 

_________________

Heaps of performance EF/L parts for sale, including supercharged VCT motor!

2002 Ford AU Series III Falcon XR8 Pursuit 250 ute - 5.6L of V8 Windsor!

Top
 Profile  
 
 
Posted: Thu Aug 02, 2007 12:54 pm 
Stock as a Rock
Offline

Posts: 170

Joined: 10th Nov 2005

Location: Canberra
ACT, Australia

xcabbi wrote:
bypass valves are only for positive displacement blowers that run as suck through throttle setups such as the eaton M series blowers.


centri like vortech, paxton, etc, they will benefit from bypass also.

 

_________________

http://www.TURBO351.com

2V 351T, 732rwhp@15psi on LPG.

Top
 Profile  
 
 
Posted: Fri Aug 03, 2007 12:04 am 
Getting Side Ways
Offline

Age: 36

Posts: 9453

Joined: 9th Nov 2004

Gallery: 4 images

Ride: Fordrunner 5.0 Turbo

Location: Wollongong
NSW, Australia

I can't quite see how as even if the throttle was open at idle they would still not be making any boost, not like a pd blower.
Top
 Profile  
 
 
Posted: Fri Aug 03, 2007 12:20 am 
Getting Side Ways
Offline
User avatar

Age: 48

Posts: 7029

Joined: 18th Apr 2005

Location: Hobart
TAS, Australia

They'll make booost regardless! under driven? then bugger all! overdriven? watch out!!!







But nothing to sing & dance about!

 

_________________

Mind f**k!!! it works on feeble minded ignorant sheeples... there's plenty of em on this site... some are very intelligent but by god they are so thick!!!

Pakrat wrote:
You can buy them seppertly

Top
 Profile  
 
 
Posted: Fri Aug 03, 2007 10:25 am 
Getting Side Ways
Offline
User avatar

Age: 36

Posts: 8655

Joined: 5th Nov 2004

Gallery: 37 images

Ride: V8 EF Futura

Location: Adelaide CBD
SA, Australia

xcabbi wrote:
I can't quite see how as even if the throttle was open at idle they would still not be making any boost, not like a pd blower.


The centrifugals prob dont flow enough to make boost at idle, but they move enough air to cause dramas lol.

At idle on my old setup, you would have a steady flow of air being vented at idle. For s**t and giggles, i put my hand over the bypass vent, the RPM dropped... engine spluttered and sounded like a bucket of s**t... it never stalled tho...

Even a slight kink in the hose i ran from the valve to its venting area near my front bumper would make the engine idle like s**t.

Having said this, ive seen setups with no bypass... which makes me think you can prob tune your way out of it.

 

_________________

I promise..... I will never die.

Fordmods Administration Group MINOR PUNKED

Top
 Profile  
 
 
Posted: Fri Aug 03, 2007 10:43 am 
Getting Side Ways
Offline

Age: 36

Posts: 9453

Joined: 9th Nov 2004

Gallery: 4 images

Ride: Fordrunner 5.0 Turbo

Location: Wollongong
NSW, Australia

How was the bypass routed in your car Mart? I'm just trying to get a visual picture of a schematic so I can work out the logic behind it all.
Top
 Profile  
 
 
Posted: Fri Aug 03, 2007 11:48 am 
Stock as a Rock
Offline

Posts: 170

Joined: 10th Nov 2005

Location: Canberra
ACT, Australia

blower is pumping air, if t/b is shut there is nowhere for it to go, although it might not register as "boost" it is a lot of volume, loading up the blower at idle, you'd be surprised how much air it actually is, bypass helps cool the blower also, by reducing load, and allowing circulation of fresh air.


sure you can tune around it or whatever, but it will always work better with a decent bypass, FYI a vortech V2 s trim on 351C, will bypass a huge ammount of air, even at light cruise, two bosch bypass isnt enough really, thats why all the blower oriented bypass valves are quite large.

 

_________________

http://www.TURBO351.com

2V 351T, 732rwhp@15psi on LPG.

Top
 Profile  
 
Display posts from previous:
Sort by  
 Page 1 of 2  [ 22 posts ]  Go to page 1, 2  Next

Who is online

Users browsing this forum: No registered users and 12 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

 

 

It is currently Mon Dec 18, 2017 4:58 am All times are UTC + 11 hours

 

 

(c)2014 Total Web Solutions Australia - Australian Web Hosting and Domain Names