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Old 04-13-2012, 04:55 PM   #601
dux10
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Originally Posted by Clark Turner View Post
Without the use of a load dyno that can hold the engine at any rpm/load AND produce a TRQ readout showing you incremental changes, THere is no way to tune the timing map correctly. There are only a few places in the US that I know of that can offer this kind of facility called a Dyno cell. The room must have an incredible fresh air cooling system. Not fans blowing on a radiator. I have been to three.

Most Hacks just add athority to the advance table and let the knock sensors tune the cars. Obviously. This is a short cut and as a result. The tune is not optimal. But to the 99 percent of the hacks out there, They just care what the dyno sheet says and if it says they made power. They are happy. If the tuners idea of tuning a car is to go for 11 to 1, run as much boost as they dare, and then crank the timing up to the edge, They are not a tuner,They are a hack and have alot to learn.

Over and out.. Time for lunch



C
So when you tune a car on the street/e-tune, how do you determine this "one perfect timing map"? I mean, afterall, every car and environment are different... So what do you do to set the car up for a cold day vs warm day or humid day vs dry day or a trip up to the mountains vs a cruise by the beach?
Tuning is not all science and will not always be "perfect." There's plenty of us that tune cars to a respectable AFR (not 11:1 all the time) with high boost (based on compressor charts, previous experience, and other research) and timing set to a level where knock does not occur under ALL conditions (e.i. aggressive driving, track, sustained 4th-5th gear pulls, etc..), that also explore other areas of the map that are used everyday such as part/light throttle, cruise, etc...
*NOTE* i will agree that there are too many "pro tuners" out there that use a dynojet to tune a car from start to finish and the tune as a whole sucks. I encounter this issue weekly....
Knowing you, I'm not offended by your statement (hell- I learn alot from the posts you share pertanent information), but my problem is you talk a big game, but not every car you tune is as "perfect" as you make them out to be based on posts like the above....
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Old 04-13-2012, 05:04 PM   #602
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Originally Posted by dux10 View Post
So when you tune a car on the street/e-tune, how do you determine this "one perfect timing map"? I mean, afterall, every car and environment are different... So what do you do to set the car up for a cold day vs warm day or humid day vs dry day or a trip up to the mountains vs a cruise by the beach?
Tuning is not all science and will not always be "perfect." There's plenty of us that tune cars to a respectable AFR (not 11:1 all the time) with high boost (based on compressor charts, previous experience, and other research) and timing set to a level where knock does not occur under ALL conditions (e.i. aggressive driving, track, sustained 4th-5th gear pulls, etc..), that also explore other areas of the map that are used everyday such as part/light throttle, cruise, etc...
*NOTE* i will agree that there are too many "pro tuners" out there that use a dynojet to tune a car from start to finish and the tune as a whole sucks. I encounter this issue weekly....
Knowing you, I'm not offended by your statement (hell- I learn alot from the posts you share pertanent information), but my problem is you talk a big game, but not every car you tune is as "perfect" as you make them out to be based on posts like the above....
Pretty much agree with all of this.
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Old 04-13-2012, 05:27 PM   #603
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Even at low load and low rpm, there is really only one advancement of timing that is proper for the engine setup as a whole.

Any sway from this will reduce power or effeciency. That range is pretty narrow. Tuners that dont work in an environment that can show this, will suggest otherwise because they do not know better.

If you hold the engine at a low load against the computer controlled LOCK, You can adjust timing up and down to find the proper setting. EGT is required here. Open source is not usable for this application. Cobb or a standalone system is required.

When you speak of timing for low octane, You must make serious compromises here in power. However, Even with this in mind, low octane fuel has only one optimal setting. Under advanced can be very harmfull. Over advanced can be very harmfull.

Without the use of a load dyno that can hold the engine at any rpm/load AND produce a TRQ readout showing you incremental changes, THere is no way to tune the timing map correctly. There are only a few places in the US that I know of that can offer this kind of facility called a Dyno cell. The room must have an incredible fresh air cooling system. Not fans blowing on a radiator. I have been to three.

Most Hacks just add athority to the advance table and let the knock sensors tune the cars. Obviously. This is a short cut and as a result. The tune is not optimal. But to the 99 percent of the hacks out there, They just care what the dyno sheet says and if it says they made power. They are happy. If the tuners idea of tuning a car is to go for 11 to 1, run as much boost as they dare, and then crank the timing up to the edge, They are not a tuner,They are a hack and have alot to learn.

Over and out.. Time for lunch

C
The range for lower load and cruise may be "pretty narrow" in terms of efficiency and power, but in terms of safety it is wider. Yes you could get a bit more efficiency out of the car by tuning on a dyno, but depending how close you were to begin with you aren't gaining that much. Even on my car experimenting with really stupid settings just to see what happens my fuel economy was not drastically different. In this case within 5-6%. I really wish I had a dyno and realtime tuning to mess with lower load stuff for fuel economy reasons but based on experimentation I also know that it isn't going to get a whole lot better than it is currently.

LOL I like your hacks comments. I've personally never seen someone tune a car like that but I can imagine it happens. Some of the maps I've seen for cars were awful enough that I believe it. My own maps were not good when I started learning. But I also only played with my own car for it until I had a better grasp and then a few friends were generous enough to let me play with their cars to learn. I know it is wrong to tune a car by targeting 11:1 afr, running as much boost as you dare, and then running timing to the edge, but it actually works. It's also done by competent tuners at times almost exactly like that when they don't have the data to test a new setup properly. Whether they admit it or not is another story. Without actually testing the car at different altitudes, temperatures, in different humidity, with different fuel from different companies with different octane ratings and alcohol content, and then also tuning without the benefit of an egt gage at each port and prior to the turbo, with per cylinder tuning ability, the tune is never going to be perfect. Thats the bottom line. Luckily the tune doesn't have to be perfect because there is room for error. Even if you didn't know anything about tuning you would know that there are different methods for tuning that work well. Otherwise the oems that design build and tune the car and expect to get 100k miles or even double and triple that would not have tuners "improving" on their work and getting more power by tuning differently.
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Old 04-14-2012, 10:01 AM   #604
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Originally Posted by dux10 View Post
So when you tune a car on the street/e-tune, how do you determine this "one perfect timing map"? I mean, afterall, every car and environment are different... So what do you do to set the car up for a cold day vs warm day or humid day vs dry day or a trip up to the mountains vs a cruise by the beach?
The ECU has provisions for this. Changes in atmospheric pressure and IAT are accounted for by comp tables. Based on what I have seen, a lot of "tuners" struggle with this concept. We read countless threads about setups that seem to be OK on the day when the car was tuned but as seasons change, the car goes all out of whack. Weak sauce. If you're tuning your car and you don't know how IAT and absolute pressure affects things, you need to stop and either educate yourself or hand the reins over to someone that can complete the job for you. I do not intend this as criticism, just advice that will save time and money. A smart person knows when they're in over their head and when it's time to call in the cavalry.

Quote:
Originally Posted by dux10 View Post
Tuning is not all science and will not always be "perfect." There's plenty of us that tune cars to a respectable AFR (not 11:1 all the time) with high boost (based on compressor charts, previous experience, and other research) and timing set to a level where knock does not occur under ALL conditions (e.i. aggressive driving, track, sustained 4th-5th gear pulls, etc..), that also explore other areas of the map that are used everyday such as part/light throttle, cruise, etc...
Tuning IS all science. Back in the day people though fire was magic and earth was flat Now we know better. There is a well defined science to how an engine needs to be managed and what happens when surrounding conditions change. There's a disturbing trend on this forum that implies that tuning is some kind of mysterious, black magic art. I think it comes from the fact that, to be frank, some science is above an average person's pay grade and people tend to have a mentality that if they don't understand what is going on, then the problem isn't with me, it's just magic. Now, don't get me wrong, and I want to ve very clear about this, tuning is not easy and I personally think most people should not attempt it. Like all other technically complicated topics, if you do not have proper background, you will likely not succeed. And even if you do have the expertise, do you have all of the tools to do it correctly? Consider what Subaru does when they develop an engine. What most people do is a poor substitute for the way it should be done. What is amazing to me is that a qualified person with limited tools can do fairly well but let's be clear about this, there is no full substitute for a proper tuning setup.
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Old 04-14-2012, 02:06 PM   #605
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Originally Posted by Ziggyrama View Post
The ECU has provisions for this. Changes in atmospheric pressure and IAT are accounted for by comp tables. Based on what I have seen, a lot of "tuners" struggle with this concept. We read countless threads about setups that seem to be OK on the day when the car was tuned but as seasons change, the car goes all out of whack. Weak sauce. If you're tuning your car and you don't know how IAT and absolute pressure affects things, you need to stop and either educate yourself or hand the reins over to someone that can complete the job for you. I do not intend this as criticism, just advice that will save time and money. A smart person knows when they're in over their head and when it's time to call in the cavalry.

I'm well aware of this and use these compensations myself. However, Clark is stating that he uses a dyno cell for optimum results. This is fine, but can the dyno cell alter the humidity, elevation, and temperature to a point where he can "correctly/perfectly" setup his compensation tables? This was my point I was trying to get across as he makes it seem as though this is the only properly way to tune "correctly" and he's the only one in the world capable of doing so....
Since the current conversation doesn't add to thread topic, I am going to leave it all alone. lol
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Old 04-14-2012, 03:50 PM   #606
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^^ Exactly.

If we could get all the elitists off their high horses we might have advanced the conversation.

As it is, and has been seemingly forever, it's a thread about ego, not information.

After too many tunes, mine and others, too many months and too many years looking for insight in here and anywhere else that the scent is keen, I'm content with the tune I've labored over too long on my own.

But the process has jaded me. And I'm burnt... out, I think.

Shortly this will be history for me. Mr. Turner, et all, can have it. Enjoy. I'll be driving a BRZ.... edit: NOT.

SeeeeeYa.

Last edited by SeeeeeYa; 07-16-2012 at 08:02 AM. Reason: Wasn't "burnt" and haven't quit.
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Old 04-14-2012, 09:49 PM   #607
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Quote:
Tuning IS all science. Back in the day people though fire was magic and earth was flat Now we know better. There is a well defined science to how an engine needs to be managed and what happens when surrounding conditions change. There's a disturbing trend on this forum that implies that tuning is some kind of mysterious, black magic art. I think it comes from the fact that, to be frank, some science is above an average person's pay grade and people tend to have a mentality that if they don't understand what is going on, then the problem isn't with me, it's just magic.
+1

And some people have a vested interest in minimizing the distribution of that understanding.
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Old 04-15-2012, 07:03 AM   #608
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Clark, my apologies if you think I am attacking you but I believe I am right on this and you appeared to be the most vocal that this system does not work and it is only for the benefit of the community as a whole. New ideas should be tested as any engineer is aware... so one of your existing customers has offered to conduct an independant impartial comparison, would you like any particular conditions or tests applied to maintain accurate test data? 1/4 mile is planned but any other test data is welcome

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Originally Posted by Ziggyrama View Post
On a bone stock setup? That seems hard to believe knowing what we know about the pressures in the uppipe. Unless there's something else I am not considering in the equation. My VE calculations showed that extending overlap past ~4400 RPMs dropped my VE.

FYI, JDM cams and ADM cams are different that USDM cams. AVCS numbers are always with respect to the resting position of the cam andd the cams themselves have different resting positions, depending on the domestic market. What that means is that the same AVCS maps for a JDM car do something different than on a USDM car. Just wanted to make that clear. The USDM STI cam positions have been published and are well understood:

Intake TDC: 5 degrees of advance
Exhaust TDC: 12 degrees of retard

What are the numbers for ADM and JDM?
Yes, a bone stock STi. Even our 5EAT STi's are pulling respectable numbers on stock setups(bye bye Mafless tuned LS2 GTO's)

USDM, SADM, MEDM, EDM and AUDM motors have the same rest positions(I had Kelford's in my last STi and can confirm, customer in ) and this represented in my graph on previous page JDM is 20 degrees cam separation though but obviously the Liberty D.AVCS has slightly different specs dependant on engine year etc

While VE is a good indicator, it is not what generates the most crank torque or acceleration. I do gas flow analysis for a full time career, this D.AVCS stuff is quite easy to calculate. Even if you calculate the possibilities in full degrees of cam angle, there is 1200 combinations per load site. My intake and exhaust columns and rows do not even 'align' since they use different values to get the right overall shape.

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I am not sure about that. This is complicated and conventional VVT science states the opposite for low load cruising situations. In cruise, you want lots of overlap to promote internal EGR to cool the combustions cycle and reduce the pumping loses. But, there's a limit to how far you can take that. Too much EGR will destabilize your combustion. It is possible that one might have dialed in too much overlap, registered knock and concluded that the car is running too much timing. By reducing overlap, you might be stabilizing the combustion which allows the car to tolerate more timing now. So, if you're on the EGR stability threshold, the above may hold true. But if you continue to reduce the overlap, you'll find that you will be dropping your timing, as you approach ideal VE. Typically, the closer you get to best VE, the less timing you will need for optimal burn. So, the big question is, would decreasing overlap bring you closer or further away from ideal VE? Depending on that answer, the timing will follow
Put it this way, if airflow is at say 29.4g/sec at cruise speed, you only need roughly 2 grams per second of fuel for a stoich mixture, 120 grams per minute or 720 grams per hour. 720 grams is what one metric litre of fuel weighs, so suddenly, is 7 litres or around 5000grams of fuel per hour so impossible?

You have taken into account inlet and exhaust valves but you missed the '3rd' valve though... the big one on the front of the inlet manifold It controls airflow and if you generate more torque, you need less throttle angle to make the same amount of power, thus more manifold vacuum and that is why exhaust AVCS needs to drop a little since... the manifold vacuum generated induces EGR
Any ideas on how I finish my sentence?
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Old 04-15-2012, 07:17 AM   #609
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^^ Exactly.
If we could get all the elitists off their high horses we might have advanced the conversation.
As it is, and has been seemingly forever, it's a thread about ego, not information.
After too many tunes, mine and others, too many months and too many years looking for insight in here and anywhere else that the scent is keen, I'm content with the tune I've labored over too long on my own.
But the process has jaded me. And I'm burnt... out, I think.
Shortly this will be history for me. Mr. Turner, et all, can have it. Enjoy. I'll be driving a BRZ.
SeeeeeYa.
Wait until you see the BRZ AVCS system lol
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Old 04-16-2012, 08:06 AM   #610
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You have taken into account inlet and exhaust valves but you missed the '3rd' valve though... the big one on the front of the inlet manifold It controls airflow and if you generate more torque, you need less throttle angle to make the same amount of power, thus more manifold vacuum and that is why exhaust AVCS needs to drop a little since... the manifold vacuum generated induces EGR
Any ideas on how I finish my sentence?
It's always about throttle, isn't it?

I did not consider effect of vacuum on the flow. Very interesting point. I will try this out in my next map rev. I already dropped my intake side considerably because more advance was just hurting numbers. I haven't been scrutinizing the exhaust side lately and clearly that was a mistake. I think I get it now. Very cool.
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Old 04-16-2012, 08:30 AM   #611
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Originally Posted by dux10 View Post
I'm well aware of this and use these compensations myself. However, Clark is stating that he uses a dyno cell for optimum results. This is fine, but can the dyno cell alter the humidity, elevation, and temperature to a point where he can "correctly/perfectly" setup his compensation tables? This was my point I was trying to get across as he makes it seem as though this is the only properly way to tune "correctly" and he's the only one in the world capable of doing so....
Since the current conversation doesn't add to thread topic, I am going to leave it all alone. lol
An experienced tuner knows what they need to dial in in the comp tables. Don't forget, if he already did 20 cars and got them working fine, do you think a 21st will be so much different? After so many samples, the picture becomes clear. All you need is a few GOOD samples where you have a car in Arizona, Colorado, Maine and Florida. Once you refine the numbers with respect to altitude and IATs, when next guy comes along, it's not a "start over from square 0" process. This is where experience comes in and this is what you're paying for when you go to a tuner.

Come on guys, this isn't any different than any other profession out there. Would you go to a DIY forum for hardwood flooring and ask the installer to teach you how to install floors, walk you through the process, help you select the products and come over to your house to overlook it for free? Of course not. You cannot expect a professional to share their know-how for the "good of the community" completely. Any info that is handed out should be considered gravy, IMO. They could be saying nothing and I would not blame them.

I don't consider myself an elitist. I know that this can be frustrating because it takes a lot of effort to really understand this topic. AVCS is arguably the toughest off all the tunable systems that you will touch. Set your expectations accordingly.

I have over a decade of experience in an engineering field and I have the benefit of scientific eduction to help me along the way. Do you need all that? No, but it helps for sure. I have shared all of my work and I posted my maps on RR along with notes and started several discussion threads to help the community. I've received many PMs regarding certain topics and I make it a point to always respond, even if I cannot help. I suspect there are many other people on this forum that do the same. If you expect that people will just spoof feed you the information, you will be disappointed. Besides, you will not learn anything if you just take what people give you without doing some of the discovery yourself.
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Old 04-16-2012, 02:37 PM   #612
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It's always about throttle, isn't it?

I did not consider effect of vacuum on the flow. Very interesting point. I will try this out in my next map rev. I already dropped my intake side considerably because more advance was just hurting numbers. I haven't been scrutinizing the exhaust side lately and clearly that was a mistake. I think I get it now. Very cool.
The throttle is pretty much everything... it is too easy to ignore as WOT is the easiest scenario.
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Old 04-20-2012, 02:21 AM   #613
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I can vouch for the throttlehappy throttle maps, car became easier to modulate.
It is well understood that manifold vacuum helps with EGR if AVCS is tuned for it, but can we quantify EGR by DIFFIRENCIAL pressure between the intake manifold and exhaust backpressure? Any exhaust improvements theoretically reduce backpressure therefore lessen EGR effect and improve scavenging.

My biggest concern with tuning avcs is loosing fuel out the exhaust valve. To determine this does anyone actually know when the ecu sprays fuel in relation to the (always changing) intake valve opening. If I were to run 25 degrees intake AVCS BTDC , does this mean the injectors are spraying into the exhaust? I understand that subaru definately has a measure for this still undefined in the definitions.
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Old 04-22-2012, 10:51 PM   #614
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Default AVCS Link standalone setup question

I'm a bit of a subanoob

I'm installing an AVCS turbo motor in a buggy with a link extreme. A little confused about the inputs. The base setup from Link only shows 2 inputs, one from the LH cam (trigger/sync) and one from the RH cam pos sensor. I figured I would need the cam sync and both cam pos sensors to make it work. I'm assuming the base map will need to be wired correctly to work with a pre-existing setup, just want to be sure i get it right the first time.

I figured the cam trigger/sync input would not reflect the actual cam position but would be more like a pre-avcs position signal since there are 3 cam sensors. Am I just way off? Please enlighten...

Thanks

Mike
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Old 04-22-2012, 10:54 PM   #615
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Very few here will be able to help you Mike. I suggest you call Neil at Performance developments in california for help wiring AVCS up.

C
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Old 04-26-2012, 05:22 PM   #616
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If I leave EXHAUST avcs solenoids and sensors unplugged in dual avcs motor (EDM 2008 STI EJ257) and dont plug the oil flow to the sprockets,
at what posiotion/angle does the exh. cams rest? And is avcs sprocket free to rotate then, or is there pressure in the lines through cams?
Looking at the stock avcs maps they have 17deg retard at max power area.
So I assume if I want to run the motor with exh. avcs disabled I need to lock the cams to that position? Or use solid sprockets which seal the cam properly as the oil seal surface is on the sprocket.

Building a spare motor to my 2003 EDM STi which is single avcs.
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Old 04-26-2012, 08:41 PM   #617
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If I leave EXHAUST avcs solenoids and sensors unplugged in dual avcs motor (EDM 2008 STI EJ257) and dont plug the oil flow to the sprockets,
at what posiotion/angle does the exh. cams rest? And is avcs sprocket free to rotate then, or is there pressure in the lines through cams?
Looking at the stock avcs maps they have 17deg retard at max power area.
So I assume if I want to run the motor with exh. avcs disabled I need to lock the cams to that position? Or use solid sprockets which seal the cam properly as the oil seal surface is on the sprocket.

Building a spare motor to my 2003 EDM STi which is single avcs.
I know that on startup the exhaust cam rests at 0 degrees and and it seems to stay that way for a while until the car warms up some and then it will target the values in the tune. I would guess that if you unplug the solenoid it would rest at zero but I don't know for sure. I think they would stay at zero throughout operation. If you want to disable ex avcs yes you need to lock it ~17 degrees or use solid sprockets which seal the cam properly.
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Old 04-27-2012, 12:27 PM   #618
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^^^ thats some trick advice. I would seal them at 20 degrees..
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Old 04-27-2012, 12:32 PM   #619
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The cams would wonder around like 4 drunks leaving the bar. Not one would be on the same path.
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Old 04-27-2012, 01:24 PM   #620
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The cams would wonder around like 4 drunks leaving the bar. Not one would be on the same path.
Thanks for confirming that. That's what I ended up too when looking at the sprockets taken apart.
Guess I will try to machine some sort of fillets to the oil chambers inside the exhaust sprockets to lock them near 20 degrees or so.
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Old 04-27-2012, 03:37 PM   #621
Ziggyrama
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Originally Posted by kakarot09 View Post
I know that on startup the exhaust cam rests at 0 degrees and and it seems to stay that way for a while until the car warms up some and then it will target the values in the tune. I would guess that if you unplug the solenoid it would rest at zero but I don't know for sure. I think they would stay at zero throughout operation. If you want to disable ex avcs yes you need to lock it ~17 degrees or use solid sprockets which seal the cam properly.
0 degrees with respect to what? The piece of info that is critical is to know what 0 means with respect to TDC. On the exhaust side, 0 retard means 12 degrees BTDC. If you're going to lock them, lock them at no more than 17 degress retard, which is 5 degrees ATDC which, coincidentally happens to be the resting position of the intake cam. The single AVCS setup that older STI's run where the exhaust side is static, this is exactly the configuration. If you go past 17 on the exhaust, you will create permanent valve overlap between intake and exhaust side which is something you really don't want. The intake side starts at 5 ATDC and 18 degrees of retard on exhaust will give you 6 ATDC. See where this is going?
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Old 05-01-2012, 08:24 AM   #622
jkopinga
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0* = No Retard from the AVCS system.
Therefore the Ex. Cam sits in the most Advanced position which is roughly 126* BTDC.
Keep in mind that normally Ex. centerlines are BTDC and Intake are ATDC.

Single AVCS cars run the Ex. Cam at 113* BTDC centerline. If we compare that to the Dual AVCS cars which run the Ex. Cam at 126* - 17* = 109* BTDC. Therefore they run more retarded.

Advancing the Ex. Cam and retarding the In. Cam therefore creating a higher LSA should certainly give better results at the topend IF you don't run into DET. Don't forget that changing CAM timing has a HUGE effect on dynamic C/R as the overlap changes.

If you must run AVCS Ex. pulleys I would do the following:

- Plug the insides with the Pulley in the 0* position as there is a spring loaded bead locking them. Use aluminium plugs for this to prevent movement. This is CRITICAL!!
- This puts the Ex. Cam at 126* BTDC. However for a more "normal" operation we might want to RETARD them by one tooth on the belt.

The CAM pulley has 48 teeth. One teeth is therefore 360* / 48 = 7.5*
Keep in mind this is CAM TIMING. Crank timing is DOUBLE that. So it changes 15*!!
However 126* - 15* = 111* BTDC. Right in between the Single AVCS 113* and the Dual AVCS 109*.... Noice

Cheers,

Jasper.
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Old 05-01-2012, 09:26 AM   #623
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Originally Posted by 5bravobravo View Post
I'm a bit of a subanoob

I'm installing an AVCS turbo motor in a buggy with a link extreme. A little confused about the inputs. The base setup from Link only shows 2 inputs, one from the LH cam (trigger/sync) and one from the RH cam pos sensor. I figured I would need the cam sync and both cam pos sensors to make it work. I'm assuming the base map will need to be wired correctly to work with a pre-existing setup, just want to be sure i get it right the first time.

I figured the cam trigger/sync input would not reflect the actual cam position but would be more like a pre-avcs position signal since there are 3 cam sensors. Am I just way off? Please enlighten...

Thanks

Mike
Hi Mike,

I'm not sure I can help you since I have never worked with the Link ECUs. However looking at what you mentioned I reckon the following:

The Cam Sync (Phase signal) is the LH sync but also the LH AVCS position signal. EG. this signal has 2 functions. The RH AVCS is just that ... A CAM position signal.

On the LH and RH AVCS positions there should be 3 KEYS that should correspond to when a Tooth is passing the sensor.

For the LH and RH sensors there should be "Latch points" or certain marks on the Crank degrees where it expects a TOOTH. EG. they should be around:

150, 510, 690 degrees for LH/RH (VVT1) (Some software swappes RH and LH )
330, 510, 690 degrees for LH/RH (VVT2) (Unfortunately the same as above applies)

Perhaps your ECU still needs some OFFSETs to be setup. On my ECU I am running:

120, 480, 660 degrees
311, 490, 672 degrees.

This is to ENSURE that the ECU reads the CAMs at exactly 0* when they are in FULL retard. EG. when this is not setup properly you may see that you are reading 1.5* of CAM or even upto 4.5* of CAM when it is not there. This WILL cause integrator wind up and slow response of the cams. Make sure the cams READ 0* or even -0.25* to make sure you are able to target and HIT 0*.

Not sure whether it helps you as you run a different ECU but I guess approach should be similar.

Cheers,

Jasper.
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Old 05-01-2012, 10:16 AM   #624
khalonen
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Originally Posted by jkopinga View Post

...

If you must run AVCS Ex. pulleys I would do the following:
....
.... Noice

Cheers,

Jasper.
Top info.
Now that I've researched more it seems that the cam sensors are different in my 2 motors. So I would need to run the EJ207 cams in the
EJ257 heads anyway because the trigger part on the intake camshaft is different.
EJ207 uses 4 trigger points at the cam and 2 wire induction sensor and EJ257 uses 3 trigger points and 3 wire HAL sensor.
Just not sure yet if the cams are interchangeable between the heads as my only set of EJ207 cams are in the running motor in the car
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Old 05-01-2012, 10:21 AM   #625
jkopinga
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Are you sure about the different CAM position wheels and sensors?? I highly doubt that.....

Cams are intechangeable as far as I know. Slightly longer duration but not that much.

Cheers,

Jasper.
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