+- JapCarForum (https://www.japcarforum.com)
+-- Forum: Cars, Cars, Cars! (https://www.japcarforum.com/forumdisplay.php?fid=11)
+--- Forum: General Car Maintenance (https://www.japcarforum.com/forumdisplay.php?fid=150)
+--- Thread: Help me understand something regarding boost... (/showthread.php?tid=8012)
Pages:
1
2
Help me understand something regarding boost... - Tango - 01-06-2019
speedfreek Exactly as I see it Stav.
The pressure is the same from the output of the charger as it is in the chamber as there are wastegates to regulate the pressure to a set max.
The psi guage doesn't measure how much air there is, merely the pressure of the air that is there - so in practice I don't believe that it is a measure of unused boost.
Isn't that what I said earlier??
Help me understand something regarding boost... - FirebirdPhil - 01-06-2019
Tango Isn't that what I said earlier??
yes
Help me understand something regarding boost... - Tango - 01-06-2019
Thanks for the confirmation, thought I was posting to myself :laugh:
Help me understand something regarding boost... - RichyUK - 01-06-2019
forget the blurb, more boost = more power
(and more likely to det)when i map cars i will genrally make 2 boost settings. last one i did that was fairly powerful made 495 bhp @ 1.5 bar boost and 535 @ 2 bar boost
Help me understand something regarding boost... - Rolex - 01-06-2019
I think boost gauges are more to indicate the density of the air being but into the cylinder. Boost cars will always have air that can't make it into the chamber reaction thats the purpose of dump valves to release any built air pressure that can not phsically be put into the engine.
Help me understand something regarding boost... - RichyUK - 02-06-2019
boost gauge is a measure of the pressure of the air which has been compressed by the turbo/supercharger. The more you compress the air (ie increased psi/bar on your boost gauge), the denser it is, so effectively you've shoved more air in. at 5 psi you'll be putting in 'x' amount of air as its compressed by that much. at 10psi its compressed more so you physically have more air able to go into the same space in the combustion chamber, hence always needing more fuel as boost increases.
dump valves are used to vent of pressure between the charger and the closed throttle body butterly valve. When you are on boost, and shut the throttle completely, the charger is still making boost but has nowhere to go as the butterfly is shut so the dumpvalve opens to vent this pressure and prevent the turbo from stalling. if you have no dump valve you will get the 'chatter' sound when you lift of as all that compressed air in the boost pipework has nowhere to go, so rebounds off the closed butterly & back towards the turbo and the compressor blades then 'chop' the air up into pockets of air causing that chatter sound.
Help me understand something regarding boost... - Tango - 02-06-2019
I think everyone is in violent agreement on this subject:bored:
Help me understand something regarding boost... - RichyUK - 02-06-2019
Tango I think everyone is in violent agreement on this subject:bored:
huh?:glare:
i was just trying to give a nice informative post about what boost is, and what a dump valve is used for.