Automotive Forums .com - the leading automotive community online! Automotive Forums .com - the leading automotive community online!
Automotive Forums .com - the leading automotive community online! 
-
Latest | 0 Rplys

Stop Feeding Overpriced Junk to Your Dogs!

GET HEALTHY AFFORDABLE DOG FOOD
DEVELOPED BY THE AUTOMOTIVEFORUMS.COM FOUNDER & THE TOP AMERICAN BULLDOG BREEDER IN THE WORLD THROUGH DECADES OF EXPERIENCE. WE KNOW DOGS.
CONSUMED BY HUNDREDS OF GRAND FUTURE AMERICAN BULLDOGS FOR YEARS.
NOW AVAILABLE TO THE GENERAL PUBLIC FOR THE FIRST TIME
PROPER NUTRITION FOR ALL BREEDS & AGES
TRY GRAND FUTURE AIR DRIED BEEF DOG FOOD
Go Back   Automotive Forums .com Car Chat > Engineering/Technical > Forced Induction
Register FAQ Community Arcade Calendar
Forced Induction Discuss topics relating to turbochargers, superchargers, and nitrous oxide systems.
Reply Show Printable Version Show Printable Version | Email this Page Email this Page | Subscription Subscribe to this Thread
 
Thread Tools
Old 09-19-2004, 03:26 PM   #16
SaabJohan
AF Enthusiast
 
Join Date: Nov 2001
Location: Borlänge
Posts: 1,098
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Legit? Another "fake" turbo...

Maximum power is at a rich mixture, around lambda .92. When making the mixture much richer than that the power will decrease. Using a leaner mixture will also decrease power but also decrease fuel consumption. The lowest fuel consumption can be found some above lambda 1.

There are formulas on how a compressor must spin to produce boost (but typically a compressor map are used), there are also formulas for power requirements and so on. The fomula on rpm depends on Eulers turbomachine equation.
SaabJohan is offline   Reply With Quote
Old 09-19-2004, 05:05 PM   #17
Neutrino
Yaya Master
 
Neutrino's Avatar
 
Join Date: Jan 2002
Location: Bucharest
Posts: 7,152
Thanks: 0
Thanked 3 Times in 2 Posts
Send a message via AIM to Neutrino
Re: Re: Legit? Another

Quote:
Originally Posted by SaabJohan
Maximum power is at a rich mixture, around lambda .92. When making the mixture much richer than that the power will decrease. Using a leaner mixture will also decrease power but also decrease fuel consumption. The lowest fuel consumption can be found some above lambda 1.

You are correct but what i was refering to is that a lot of manufacturers seem to tune very conservativelly with very rich AF ratios especially at WOT or high rpm. Cars like the EVO even go below 10.0 AF (.68 lambda) above 5000 RPM. I presume manufacturers do this to have a good safety margin against detonation.

In those cases remapping of the ECU with leaner numbers will increase the power quite a bit. And this seems to apply to a lot of cars, and this is what i was refering to. I did not mean go above 14.70 stoich (1.0 lambda) into the lean territory.

I just meant go above very rich ratios and closer (not above) to the 13.57 (.92 lambda). This should make more power and give better MPG.
__________________

(\__/)
(='.'=) This is Bunny. Copy and paste bunny into your
(")_(") signature to help him gain world domination
Neutrino is offline   Reply With Quote
Old 09-20-2004, 11:33 AM   #18
SaabJohan
AF Enthusiast
 
Join Date: Nov 2001
Location: Borlänge
Posts: 1,098
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Re: Re: Legit? Another

Quote:
Originally Posted by Neutrino
You are correct but what i was refering to is that a lot of manufacturers seem to tune very conservativelly with very rich AF ratios especially at WOT or high rpm. Cars like the EVO even go below 10.0 AF (.68 lambda) above 5000 RPM. I presume manufacturers do this to have a good safety margin against detonation.

In those cases remapping of the ECU with leaner numbers will increase the power quite a bit. And this seems to apply to a lot of cars, and this is what i was refering to. I did not mean go above 14.70 stoich (1.0 lambda) into the lean territory.

I just meant go above very rich ratios and closer (not above) to the 13.57 (.92 lambda). This should make more power and give better MPG.
Usually there isn't any margin against detonation as active systems are used to detect and prevent knock, and what I know they usually try to map the engines as close to lambda 1 for as long as possible to allow the catalytic converter to work. Typically ignition is first retarded, then fuel is enriched, but there can also be some fuel enrichment to improve cooling as a retarded ignition causes very high exhaust gas temperatures.

If they use a maxture that rich I'll ussume that they have some good reasons for it.
SaabJohan is offline   Reply With Quote
Old 09-20-2004, 08:24 PM   #19
ricergribbs
AF Enthusiast
 
Join Date: Dec 2003
Location: chicago, Illinois
Posts: 160
Thanks: 0
Thanked 0 Times in 0 Posts
Send a message via AIM to ricergribbs
Re: Legit? Another "fake" turbo...

lol try to avoid those. ive actually heard of the blades shattering and getting sucked into the engine. lets just say that it definetly aint pretty...
ricergribbs is offline   Reply With Quote
Old 09-20-2004, 11:04 PM   #20
Pavlo
AF Enthusiast
 
Pavlo's Avatar
 
Join Date: May 2004
Location: Alpharetta, Georgia
Posts: 1,075
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Legit? Another "fake" turbo...

Is it like and electronic propeller?
Leave blower would work more efficiently, lol
I wonder what fraction of a horsepower does it add?
__________________
VR6> Anything
FWD sucks for understeer? Swaybars do magic.
Pavlo is offline   Reply With Quote
 
Reply

POST REPLY TO THIS THREAD

Go Back   Automotive Forums .com Car Chat > Engineering/Technical > Forced Induction


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 07:11 PM.

Community Participation Guidelines | How to use your User Control Panel

Powered by: vBulletin | Copyright Jelsoft Enterprises Ltd.
 
 
no new posts