Most excellent forum! - Page 2 - Fuel Economy, Hypermiling, EcoModding News and Forum

jpgmtech · 04-24-2008, 10:11 AM

Quote:

Originally Posted by Daox

Same here. I have a zeitronix wideband zt-2 system on the Matrix and it would take nothing to lean it out and get 40 mpg all day with the wife driving. However, with all I have learned about emissions its really not worth it.

Welcome to the site.

Thanks!

BTW, in my opinion (haven't done the research to gather the data to back this up) the major contributor to smog (NOx, particulates) is the diesel engine. They have started to clean up in trucks since mid-2004, but think of all of the pre-2004 diesels out there! They were not even required to have a PCV, no TWC (three-way cat), no EGR, just raw particulates, NOx and HC's being thrown out the tailpipe! And usually in huge quantities as they are mostly large engines...

However diesels are getting much better with 2007.5 requirements, and we can look forward to more improvements 2010.

Suffice to say that a modern OBDII gasoline engine is far far cleaner than the worst emissions offenders.

MetroMPG · 04-24-2008, 10:53 AM

Sounds like you've got a good depth of knowledge. Glad you decided to sign up. Out of curiousity, what led you here?

jpgmtech · 04-24-2008, 12:09 PM

Quote:

Originally Posted by MetroMPG

Sounds like you've got a good depth of knowledge. Glad you decided to sign up. Out of curiousity, what led you here?

It's a long story... I've always had a thing for fuel economy and tweaking, been a closet hobby of mine. I live right in the smack of the hummer/diesel truck/suv land in the oilfields of alberta, so my business generally involves the worst consuming vehicles out there. I got into ECM tuning and that opened up a new avenue of tweaking.

What led me here: I let a computer geek buddy of mine know about my exploits with the chevy sprint. He decided to do some research and found several websites like this one and let me know about it. I didn't come back to it until I was doing research for an article I am writing for a magazine about fuel economy (for diesel powered trucks of all things... see previous post...) That tweaked my memory and I started googling. Honestly, seeing the Geo Metro's and that radical aero Honda Civic complete with wires and equipment all over the dash got me hooked on this site!

It's actually exciting to see that there are others out there who have minds that work like mine!

I'll tell you about my future project (if it works out) when I have more time...

At some point I'll do a writeup on the new GM Hybrids too... I've just finished some training on them.

SVOboy · 04-24-2008, 12:13 PM

Thanks for hanging out with us, I'm really excited to see what you have to say about the GM Hybrids,

cfg83 · 04-24-2008, 03:14 PM

jpgmtech -

Quote:

Originally Posted by jpgmtech

Thanks!

BTW, in my opinion (haven't done the research to gather the data to back this up) the major contributor to smog (NOx, particulates) is the diesel engine. They have started to clean up in trucks since mid-2004, but think of all of the pre-2004 diesels out there! They were not even required to have a PCV, no TWC (three-way cat), no EGR, just raw particulates, NOx and HC's being thrown out the tailpipe! And usually in huge quantities as they are mostly large engines...

However diesels are getting much better with 2007.5 requirements, and we can look forward to more improvements 2010.

Suffice to say that a modern OBDII gasoline engine is far far cleaner than the worst emissions offenders.

My hope is to be able to piggy-back on this technology and get my hands on an affordable NOx sensor that is intended for diesels. In the event that I do an engine mod that effects the 02 sensor, I can monitor my normal gasser for NOx compliance.

CarloSW2

cfg83 · 04-24-2008, 03:17 PM

jpgmtech -

Quote:

Originally Posted by jpgmtech

...

I'll tell you about my future project (if it works out) when I have more time...

At some point I'll do a writeup on the new GM Hybrids too... I've just finished some training on them.

I already have a question about the first GM hybrids. Could the Saturn-Vue "mild hybrid" drivetrain be transferred into a Saturn Ion? I ask because I think they had the same generation of 2.X Ecotec engine. This is a "just for fun" question. I don't have the mechanical skillzzz to do it.

CarloSW2

jpgmtech · 04-24-2008, 04:06 PM

Quote:

Originally Posted by cfg83

jpgmtech -

I already have a question about the first GM hybrids. Could the Saturn-Vue "mild hybrid" drivetrain be transferred into a Saturn Ion? I ask because I think they had the same generation of 2.X Ecotec engine. This is a "just for fun" question. I don't have the mechanical skillzzz to do it.

CarloSW2

Possible, but difficult to say the least. Easier to just go out and buy a Saturn Aura hybrid though, 2.2 ecotec with more or less the same mild hybrid hardware. Chevy Malibu hybrid also uses this system.

The total claimed city economy benefit is 12% over the non-hybrid Aura/Malibu. But only about 5% of the gains actually come from the hybrid portion. Most of the gains are from fuel-economy tuning in the ECM and low rolling resistance tires. I'll post a table from my training info later...

By far the best gaining hybrid and most useful that GM produces is the two-mode system in the Hybrid Tahoe/Yukon. Lots of technology there, wished they got this into the small cars though. The Malibu hybrid is almost a waste of money...

Daox · 04-24-2008, 04:29 PM

Quote:

Originally Posted by jpgmtech

BTW, in my opinion (haven't done the research to gather the data to back this up) the major contributor to smog (NOx, particulates) is the diesel engine. They have started to clean up in trucks since mid-2004, but think of all of the pre-2004 diesels out there! They were not even required to have a PCV, no TWC (three-way cat), no EGR, just raw particulates, NOx and HC's being thrown out the tailpipe! And usually in huge quantities as they are mostly large engines...

However diesels are getting much better with 2007.5 requirements, and we can look forward to more improvements 2010.

Suffice to say that a modern OBDII gasoline engine is far far cleaner than the worst emissions offenders.

You are quite right that diesels are a much larger polluter of NOx when compared to gasoline engines. I just still see the effects of NOx as horrible. At the very least I would go have a 5 gas analysis done to make sure my NOx emissions weren't too out of check. I'd be happy increasing FE by 10% if NOx goes 10%, but not if NOx increased faster than FE.

I look forward to the GM hybrid review and the break down of the FE per alteration.

jpgmtech · 04-24-2008, 04:45 PM

Quote:

Originally Posted by Daox

You are quite right that diesels are a much larger polluter of NOx when compared to gasoline engines. I just still see the effects of NOx as horrible. At the very least I would go have a 5 gas analysis done to make sure my NOx emissions weren't too out of check. I'd be happy increasing FE by 10% if NOx goes 10%, but not if NOx increased faster than FE.

I agree. There is a saturation point where the reducing cat cannot help anymore, and that depends on the size of the cat and the vehicle. A 5-gas analyzer and a dyno is the best way to determine this.

Unfortunately GM has deleted the EGR valve off of several vehicles, using other means to control NOx. This is ok, but they have also killed a little bit of spark timing to hedge in the emissions requirements, which kills a bit of economy. If they kept the EGR valve, the other improvements would have made it possible to maximize the efficiency of the engine... strange decisions they make, while claiming to improve fuel economy! But then it looks like they were trying to save some money somewhere.

Ok, enough ranting...

BTW for all those wanting to know what NOx is: Nitrogen Oxides in it's various forms that are a particularly nasty pollutant responsible for acid rain and such.