Going to the dyno tomorrow....update with bad pics 11/26 :(

Steeb · Post by **Steeb** » January 31st, 2007, 2:36 pm

once again, timing does NOT affect afr's its not magic its math.

to keep this simple, we'll keep the same units of measurements
example 1:
1.6L engine displaces 1.6L of air. lets say our targed afr is 13:1 so to get a target afr we need .0123L of fuel for every 1.6L of air. so like i said, IF your ve table is correct, the only thing that can change your afr is if you have improved the ve of the engine. the egt will change but the afr will never change if your ve table is correct.

the reason that afr's dont change when timing is adjusted is because no matter when u fire the ignition, the volume of air that enters a cylinder at a given load vs rpm never changes unless you improve the engines ve somehow to make it run leaner.

example 2:
1.6L of air with .0123L of fuel is going to have a 13:1 afr if the spark plug fires or not.

example 3:
if an engine is at 50% ve where ever it may be load vs rpm, it would injest .8L of air which uses .0615L of fuel for 13:1 afr. and again if the spark plug fires or not, it will still have a 13:1 afr

there is no if u adjust your timing and u lean out.... if it was lean after adjusting timing, it was lean before adjusting timing.

that is great that you have tuned a b6 to have good power. and as a passionate enthusiast if you are into tuning, i would suggest getting proper training and certification instead of suggesting people to turn their engines into a ticking time bomb like yours was 10,000 miles later. rods dont just break, with too much timing you are putting more load on the crank and the rod as well as the cylinder walls. too much timing causes fatigue on the weakest link which for the b6 is the rods. in many cases people "spin a bearing" which is caused when the cylinder pressure gets high enough to squeeze the oil from between the bearings and the rods causing heat from metal to metal friction which then causes the bearing to attach itself to the rod and thus spin a bearing. what does cylinder pressure have to do with timing?? everything! what does timing have to do with afr? nothing. the reason egt rise when advancing timing is because the combuston process is started later which means less time before the exhaust valve opens. this means that there is less time to absorb heat into the engine and egt is higher than with less aggressive ignition timing.

reference to timing in my posts is for ignition because changing cam timing changes the engines ve. changing cam timing can change the afr. are you talking about changing cam timing or the ignition timing?

JWMotorsports · Post by **JWMotorsports** » January 31st, 2007, 6:18 pm

Ummm...ignition timing DOES change the VE of an engine. If you retard the timing you'll have a loss in power due to the energy of the full cumbustion partially exiting the exhaust port giving only partial energy transfer to the power stroke. This will have less push on the power stroke causing the other cylinders intake stroke to be less potent due to slower piston speeds...directly decreases the engines VE. Therefore when you advance timing it increases piston speed directly affecting and increasing the engines VE....requiring more fuel not just for AFR reasons but for cooling on high pressure high power engines. Advancing the time is kind of like a stroker kit because it generates more power...mostly torque... from haveing a longer time to push down on the piston giving higer piston speeds. Peak Torque requires a richer AFR than peak HP...which a lot of people don't understand....they usually only look at rpm and hp.

As for AFR's I assumed you were talking about watching a wideband and not actually calculating an ideal AFR...however it is still affected by engine timing because it changes the piston speed which directly effects VE. This is why you always purposly program the engine rich before testing. If your method was fool proof there would be no need for tuners as the Standalones would beable to do all the tuning them selves with no further tuning needed.

Ticking time bomb....are you even aware what cyclic fatigue is??? When you flex a piece of metal bi directional repeatedly it WILL break. I don't care what rods you have if your making enough power to flex them they WILL break even if your not detinating. I've pulled the plugs checking them as well for detination. After 7,000 miles at 400+WHP the ceramic insulators were still white with a tad of carbon around the outer ring of the electrode base indicating a slightly rich mix which is what you have to run on a engine boosted 20+psi on pump gas. No shiney specs what so ever...which would have indicated detination. The rods just reached there limit of "x" cycles at "x" load before cylic fatigue snapped it. Also...if it had been from detination or to much ignition advance over time the other 3 rods would have been bent at the top and they are still straight....and before you ask, yes I HAVE seen bent rods like that and know it was due to excessive timing...I tried to tell the guy but he wouldn't listen...3 months later he cracked a piston while playing with the boost.

EGTs....you got your butt backwards on that one...advancing the timing ignites the mixture earlier...not later...and it makes MORE power due to a LONGER combustion cycle requireing more fuel....because it increases the engines VE. This is what generates more heat because the mix was burned more completely causing it to create higher cylinder pressures and faster piston speeds...which directly increases friction as well. You will actually see EGTs drop below normal when leaning the mix out to far. This is why you can't tune based solely off of EGTs.

One more thing you definately need to keep in mind is combustion chamber and piston design greatly effects the flame front speed of combustion which throws a real "kink" in the mathmatics your using for your AFR's as well. Your calculating off of "Ideal" measurements and situations...the real world is a bit of a different animal even when you know what your measurements and speeds are...then comes friction, drag, temp (both ambiant and port), surface finishes, ring gap, piston to wall clearances, etc...

I've learned about building engines and tuning from some of the best in the industry. I'm also a "Design Engineer" for a living, working for a multi million dollar industrial manufacturer....been there since 2001. As for whom I've learned engine building from...one held all the local drag strip records for YEARS starting in the mid 80's. He built and ran a Naturally Aspirated 454 Pro Street car that ran 7's back in the mid 80's (thats 1/4 mile). It was built from "Junk Parts" that the Pro's were tossing in the trash. He's built many other winning cars as well. As far as tuning I have years of studing and a few years of hands on with multiple systems and setups, the best book I've ever read is "How to Tune and Modify Engine Management Systems" by Jeff Hartman. The information in the book was aquired from mainly super tuner Bob Norwood (has built n tuned MANY of the top import drag cars amongst exotic cars, domestics, etc...) and Electromotive Inc. I've also got a LOT of experiance and knowlege in electronics and most anything mechanical. I orginall went to school to become a Network Administrator...Took training for A+, N+, MCP, MCSE, & CCNA Liscenses. Was a certified repair tech for Pyxis Systems (controlled narcotic/ drug distribustion and accounting systems that are widely used in most hospitals an many doctors offices). There isn't much I can't do. My Grandfater was a Production Engineer for GE and Genicom...he was one of the gentlemen that helped to develope the tiles used on the Space Shuttle. I take after him when it comes to engineering.

cjthor · Post by **cjthor** » January 31st, 2007, 6:37 pm

JWMotorsports wrote:Ummm...ignition timing DOES change the VE of an engine. If you retard the timing you'll have a loss in power due to the energy of the full cumbustion partially exiting the exhaust port giving only partial energy transfer to the power stroke. This will have less push on the power stroke causing the other cylinders intake stroke to be less potent due to slower piston speeds...directly decreases the engines VE. Therefore when you advance timing it increases piston speed directly affecting and increasing the engines VE....requiring more fuel not just for AFR reasons but for cooling on high pressure high power engines. Advancing the time is kind of like a stroker kit because it generates more power...mostly torque... from haveing a longer time to push down on the piston giving higer piston speeds. Peak Torque requires a richer AFR than peak HP...which a lot of people don't understand....they usually only look at rpm and hp.

As for AFR's I assumed you were talking about watching a wideband and not actually calculating an ideal AFR...however it is still affected by engine timing because it changes the piston speed which directly effects VE. This is why you always purposly program the engine rich before testing. If your method was fool proof there would be no need for tuners as the Standalones would beable to do all the tuning them selves with no further tuning needed.

Ticking time bomb....are you even aware what cyclic fatigue is??? When you flex a piece of metal bi directional repeatedly it WILL break. I don't care what rods you have if your making enough power to flex them they WILL break even if your not detinating. I've pulled the plugs checking them as well for detination. After 7,000 miles at 400+WHP the ceramic insulators were still white with a tad of carbon around the outer ring of the electrode base indicating a slightly rich mix which is what you have to run on a engine boosted 20+psi on pump gas. No shiney specs what so ever...which would have indicated detination. The rods just reached there limit of "x" cycles at "x" load before cylic fatigue snapped it. Also...if it had been from detination or to much ignition advance over time the other 3 rods would have been bent at the top and they are still straight....and before you ask, yes I HAVE seen bent rods like that and know it was due to excessive timing...I tried to tell the guy but he wouldn't listen...3 months later he cracked a piston while playing with the boost.

EGTs....you got your butt backwards on that one...advancing the timing ignites the mixture earlier...not later...and it makes MORE power due to a LONGER combustion cycle requireing more fuel....because it increases the engines VE. This is what generates more heat because the mix was burned more completely causing it to create higher cylinder pressures and faster piston speeds...which directly increases friction as well. You will actually see EGTs drop below normal when leaning the mix out to far. This is why you can't tune based solely off of EGTs.

One more thing you definately need to keep in mind is combustion chamber and piston design greatly effects the flame front speed of combustion which throws a real "kink" in the mathmatics your using for your AFR's as well. Your calculating off of "Ideal" measurements and situations...the real world is a bit of a different animal even when you know what your measurements and speeds are...then comes friction, drag, temp (both ambiant and port), surface finishes, ring gap, piston to wall clearances, etc...

I've learned about building engines and tuning from some of the best in the industry. I'm also a "Design Engineer" for a living, working for a multi million dollar industrial manufacturer....been there since 2001. As for whom I've learned engine building from...one held all the local drag strip records for YEARS starting in the mid 80's. He built and ran a Naturally Aspirated 454 Pro Street car that ran 7's back in the mid 80's (thats 1/4 mile). It was built from "Junk Parts" that the Pro's were tossing in the trash. He's built many other winning cars as well. As far as tuning I have years of studing and a few years of hands on with multiple systems and setups, the best book I've ever read is "How to Tune and Modify Engine Management Systems" by Jeff Hartman. The information in the book was aquired from mainly super tuner Bob Norwood (has built n tuned MANY of the top import drag cars amongst exotic cars, domestics, etc...) and Electromotive Inc. I've also got a LOT of experiance and knowlege in electronics and most anything mechanical. I orginall went to school to become a Network Administrator...Took training for A+, N+, MCP, MCSE, & CCNA Liscenses. Was a certified repair tech for Pyxis Systems (controlled narcotic/ drug distribustion and accounting systems that are widely used in most hospitals an many doctors offices). There isn't much I can't do. My Grandfater was a Production Engineer for GE and Genicom...he was one of the gentlemen that helped to develope the tiles used on the Space Shuttle. I take after him when it comes to engineering.

Awwwww shut up jeremy.....youre making it allllllllll up arent ya!!! LOL j/k..

Steeb · Post by **Steeb** » January 31st, 2007, 8:03 pm

excuse me, my mistake on the advancing/retard timing thing. you are correct. advancing timing is sparking earlier. i sometimes mix up the less is more, more is less. im at work so my brain is jumbled up with numbers but hey, the more times someone mentions something i do or say incorrectly, the more likely ill stop making the mistake

however, changing the ve of an engine would be like installing headers, larger tb, or f/i. changing ignition timing does nothing to make the engine volume increase. if an engine is running at more than 100% ve, it is most likely an f1 engine or it has f/i

there are many old school tuners like bob norwood claim that there is no way to calculate barometric changes in air density for changes in altitude or air temperature. there are also more ems mfg's that also believe this even when confronted, most refused to fix the issue. it would have been better if you did not even mention bob norwood even tho there are many more old school tuners who refuse to believe it. being able to tune a car for wot is not the same as tuning it for reliability and daily drivability. anyone can tune wot race car but at anything less than 95% throttle, the car drive like total doo doo

if everyone could afford a top of the line autronic, then no tuners would be needed because they can in fact self tune quite well. thank god not many people can or i would be out of a job.

i think we would be better off taking this to the new engine electronics section. were totally thread jacking jarid

osargeant · Post by **osargeant** » April 1st, 2007, 2:26 pm

Hi Jarid,

Any update on the car in terms of dyno numbers or track times?

cjthor · Post by **cjthor** » April 1st, 2007, 2:27 pm

osargeant wrote:Hi Jarid,

Any update on the car in terms of dyno numbers or track times?

not yet. car goes back to the dyno next week hopefully.

cjthor · Post by **cjthor** » April 10th, 2007, 8:15 pm

Droppin her off tomorrow am to get the two step rev limiter set up and dyno tuned. Got a full tank of race gas....at 9 bucks a gallon!! nuts eh? Will have results Thursday!

cjthor · Post by **cjthor** » April 12th, 2007, 4:51 pm

my car made 300whp@18psi

Tunes67 · Post by **Tunes67** » April 12th, 2007, 5:23 pm

Dang Jarid.. congrats

Gonna head to the track and surprise some folks?

Tunes67

cjthor · Post by **cjthor** » April 12th, 2007, 5:25 pm

Tunes67 wrote:Dang Jarid.. congrats Gonna head to the track and surprise some folks?

Tunes67

na.....friggin car blew the radiator on the way back from the dyno.. After that I NEED AN INTAKE MANIFOLD!!! The stock one is just way too restrictive.

Tunes67 · Post by **Tunes67** » April 12th, 2007, 5:42 pm

Thought about having it Extrude Honed for better flow? You could get the head and intake manifold done together to maximize air flow. Bummer about the radiator though

Tunes67

cjthor · Post by **cjthor** » April 12th, 2007, 6:09 pm

Tunes67 wrote:Thought about having it Extrude Honed for better flow? You could get the head and intake manifold done together to maximize air flow. Bummer about the radiator though

Tunes67

Head is done...just need the intake mani worked on. I definitely want a short runner intake mani.

JWMotorsports · Post by **JWMotorsports** » April 14th, 2007, 9:39 am

300WHP @ 18psi on your turbo is a good sign. Crank up the boost and you should be able to get around 400WHP on the stock intake manifold.

lol...sorry to hear about your radiator....check my reply I just left on your Intake Manifold post.

P.S.

Welcome to the blown stock radiator club!

cjthor · Post by **cjthor** » April 14th, 2007, 3:49 pm

JWMotorsports wrote:300WHP @ 18psi on your turbo is a good sign. Crank up the boost and you should be able to get around 400WHP on the stock intake manifold.

lol...sorry to hear about your radiator....check my reply I just left on your Intake Manifold post.

P.S.

Welcome to the blown stock radiator club!

stock intake is a big restriction. the virs system was doing bad things on the dyno. The radiator went cuz of the intercooler rubbing on it!

JWMotorsports · Post by **JWMotorsports** » April 14th, 2007, 7:11 pm

The VRIS is bad! We had problems with it on Timmys car back when we slapped a Mitsu16G turbo on it with left over parts. When the VRIS changes you'll actually see the engine lean out for a second as it can't compensate for the quick change (the position your map sensor is reading from makes a differance hear as youll need be closer to the intake ports. Our solution since the turbo responds well was to simply disconnect the vac line on the VRIS so that it stayed open and kept the manifold at its highest flow point. The car actually seemed to like it that way and the only negative effect was at extremely low rpms...solution, downshift