"boost saver" - silly idea or invention of the century?
06-14-2010, 10:58 PM
#28
Elite Member
Join Date: Dec 2008
Location: Colorado
Posts: 1,642
Total Cats: 36
Yep, I was thinking of 273 and celsius. Its not a linear translation. 70F is roughly 294K when one actually does it right. So the volume just went down a good bit. The idea still wont really work.
For one thing, when you open the valve, like Sav said, your flow rate out of the storage tank will drop really fast. So in the first instant you might get 10psig from it, but that will drop off rapidly. Within a few tenths it will be spent.
The idea must die now.
For one thing, when you open the valve, like Sav said, your flow rate out of the storage tank will drop really fast. So in the first instant you might get 10psig from it, but that will drop off rapidly. Within a few tenths it will be spent.
The idea must die now.
Reply
0
0
06-22-2010, 12:02 PM
#32
Elite Member
iTrader: (2)
Join Date: Jan 2007
Location: Los Angeles, CA
Posts: 8,682
Total Cats: 130
**** it, why not put a damn turbine and on your wastegate dump tube and use it to power an air compressor which discharges in the intake tract at WOT for when manifold pressure is below your target boost level? Driveability be damned I think this is more like what you are thinking about right?
Reply
0
0
06-29-2010, 10:54 PM
#34
Senior Member
Join Date: May 2006
Posts: 917
Total Cats: -8
There actually was a semi-viable electric supercharger about 10 years ago. It used an Roots type blower and was attached to what looked like a starter motor and used a capacitor to deliver the power iirc. It was only good for 15 or so seconds of boost so it was kind of like a push to pass system. No idea where that crap went.
Reply
0
0
06-29-2010, 11:31 PM
#35
Junior Member
Join Date: Jun 2007
Location: Grayslake IL
Posts: 407
Total Cats: 2
There actually was a semi-viable electric supercharger about 10 years ago. It used an Roots type blower and was attached to what looked like a starter motor and used a capacitor to deliver the power iirc. It was only good for 15 or so seconds of boost so it was kind of like a push to pass system. No idea where that crap went.
******* garbage, http://www.boosthead.com/product.php
Reply
0
0
07-11-2010, 09:59 AM
#36
Newb
Join Date: Mar 2007
Posts: 31
Total Cats: 0
You don't need all the gas law stuff to figure this out....
1) Let's say it is a 2 liter engine running 3000 RPM at wide open throttle. That's 50 RPS. Being a 4-stroke, it is only taking air every other revolution. So that's 50/2 cycles/sec * 2 liters/cycle = 50 liters/sec for wide open throttle at 3000 RPM.
2) Let's say you run 10 psi of boost and want your "boost saver" to provide boost starting 10 psi and depleting down to 5 psi over 0.5 seconds. Example: a) Have 10 psi 'on tap', b) start routing from "boost saver" to throttle, c) pressure drops as "boost save" is depleted such that "saved boost" is down to 5 psi after 1/2 second when, presumably, d) turbo has spun up enough to make 5 psi of boost and is building toward 10 psi.
3) That's about 25 psi absolute down to 20 psi absolute pressure, i.e. 1/5th reduction. So now we can calculate the size of "boost saver" we'll need.
4) 5 * 50 liters/sec * .5 sec = 125 liters or approximately 30 gallons.
You can play with RPMs and displacements, but the above tells you what matters.... You'd need to replace the pax seat with a 25 or 30 gallon pressure vessel and associated air plumbing. Not very practical even if it was safe.
M.
1) Let's say it is a 2 liter engine running 3000 RPM at wide open throttle. That's 50 RPS. Being a 4-stroke, it is only taking air every other revolution. So that's 50/2 cycles/sec * 2 liters/cycle = 50 liters/sec for wide open throttle at 3000 RPM.
2) Let's say you run 10 psi of boost and want your "boost saver" to provide boost starting 10 psi and depleting down to 5 psi over 0.5 seconds. Example: a) Have 10 psi 'on tap', b) start routing from "boost saver" to throttle, c) pressure drops as "boost save" is depleted such that "saved boost" is down to 5 psi after 1/2 second when, presumably, d) turbo has spun up enough to make 5 psi of boost and is building toward 10 psi.
3) That's about 25 psi absolute down to 20 psi absolute pressure, i.e. 1/5th reduction. So now we can calculate the size of "boost saver" we'll need.
4) 5 * 50 liters/sec * .5 sec = 125 liters or approximately 30 gallons.
You can play with RPMs and displacements, but the above tells you what matters.... You'd need to replace the pax seat with a 25 or 30 gallon pressure vessel and associated air plumbing. Not very practical even if it was safe.
M.
Reply
0
0
