Boost Monitoring? - Page 2

Tony Curcio · 01-29-2015, 10:15 AM

Thank you, that makes sense. I was asking questions because I wanted to know.

The BTCC also mandates factory spec cams, more like Pure Stock than NHRA Stock, so maybe boost monitoring works for them for that reason.

D.Johns · 01-31-2015, 04:58 PM

Like stated the boost is a measurment of back pressure with-in the system. A supercharger will not spin faster or slower in order to regulate this pressure like a turbocharger would. That system uses a waste gate to bleed off the exhaust pressure in order to change impeller speed to maintain a certain boost pressure in the intake manifold.

In a supercharged set-up there are several ways to change how much air the supercharger will move. Most of them are checked in tech... It's up to the competitors to figure out how to make more HP given the set rules.

FS Fan · 04-29-2015, 03:28 PM

The only person I know of who was disqualified for a pulley size was actually making LESS boost with a larger supercharger pulley. Which seems counter-intuitive as you can lots of legal things to slow a car but rules are rules.

I believe there is a boost monitoring and limit system in Pro Mod for the turbo cars. On a turbo it might make more sense.

The spirit of Stock to me is that mechanical limits to max airflow cannot be changed. I.E. valve size, port size/shape including the runner found in the intake, cam lift, throttle body size, etc. So monitoring max airflow by pulley size seems logical with a positive displacement supercharger like all these cars run.

In Super Stock however I think a rules revision might be worthwhile on pulley size and within the spirit of the rules.

rognelson777 · 05-04-2015, 02:47 PM

Interesting conversation, but you cannot just single out boost as a separate item, a supercharger is a engine component, just like a camshaft is and boost is a function of a operating engine.

If you change a camshaft (in stock IE change duration) and the engine can rev higher it can build more boost and just like every other component has limits.

I try to relate it this way, years ago the key was to put the biggest carb on a car you could, but if not matched to the combo, to large was really worthless.

01-29-2015, 10:15 AM	#11
Tony Curcio Member Join Date: Mar 2002 Location: West Chester, PA Posts: 271 Likes: 1 Liked 4 Times in 1 Post	Re: Boost Monitoring? Thank you, that makes sense. I was asking questions because I wanted to know. The BTCC also mandates factory spec cams, more like Pure Stock than NHRA Stock, so maybe boost monitoring works for them for that reason. __________________ Tony Curcio 1860 STK

01-31-2015, 04:58 PM	#12
D.Johns Member Join Date: Dec 2011 Location: Indiana Posts: 437 Likes: 15 Liked 18 Times in 6 Posts	Re: Boost Monitoring? Like stated the boost is a measurment of back pressure with-in the system. A supercharger will not spin faster or slower in order to regulate this pressure like a turbocharger would. That system uses a waste gate to bleed off the exhaust pressure in order to change impeller speed to maintain a certain boost pressure in the intake manifold. In a supercharged set-up there are several ways to change how much air the supercharger will move. Most of them are checked in tech... It's up to the competitors to figure out how to make more HP given the set rules. __________________ 2014 Cobra Jet FS/XX #3345 STK/SS Like us on http://www.facebook.com/pages/Daniel...25886327426822

04-29-2015, 03:28 PM	#13
FS Fan Junior Member Join Date: Apr 2014 Posts: 34 Likes: 0 Liked 1 Time in 1 Post	Re: Boost Monitoring? The only person I know of who was disqualified for a pulley size was actually making LESS boost with a larger supercharger pulley. Which seems counter-intuitive as you can lots of legal things to slow a car but rules are rules. I believe there is a boost monitoring and limit system in Pro Mod for the turbo cars. On a turbo it might make more sense. The spirit of Stock to me is that mechanical limits to max airflow cannot be changed. I.E. valve size, port size/shape including the runner found in the intake, cam lift, throttle body size, etc. So monitoring max airflow by pulley size seems logical with a positive displacement supercharger like all these cars run. In Super Stock however I think a rules revision might be worthwhile on pulley size and within the spirit of the rules.

05-04-2015, 02:47 PM	#14
rognelson777 Member Join Date: Dec 2010 Posts: 372 Likes: 20 Liked 132 Times in 72 Posts	Re: Boost Monitoring? Interesting conversation, but you cannot just single out boost as a separate item, a supercharger is a engine component, just like a camshaft is and boost is a function of a operating engine. If you change a camshaft (in stock IE change duration) and the engine can rev higher it can build more boost and just like every other component has limits. I try to relate it this way, years ago the key was to put the biggest carb on a car you could, but if not matched to the combo, to large was really worthless.