using a boost controller?
using a boost controller?
does anyone have a boost controller on their evo 8 yet??
If so, how much did you alter stock boost and how is the car running with a higher boost?? Any problems??
If so, how much did you alter stock boost and how is the car running with a higher boost?? Any problems??
Originally posted by Eric Lyublinsky
I think you really don't want to push over 19psi with out EM.
I think you really don't want to push over 19psi with out EM.
-Shahul
Evolved Member
Joined: Mar 2003
Posts: 564
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From: San Diego
EM= Engine Management
when increasing boost you also need to increase fuel so that you dont run a "lean mixture". from my understanding, the stock ecu will only let you boost to a certain point until it cuts fuel delivery, hence why you would need some kind of EM to override and compensate.
-randy
when increasing boost you also need to increase fuel so that you dont run a "lean mixture". from my understanding, the stock ecu will only let you boost to a certain point until it cuts fuel delivery, hence why you would need some kind of EM to override and compensate.
-randy
Originally posted by nine4surfah
EM= Engine Management
when increasing boost you also need to increase fuel so that you dont run a "lean mixture". from my understanding, the stock ecu will only let you boost to a certain point until it cuts fuel delivery, hence why you would need some kind of EM to override and compensate.
-randy
EM= Engine Management
when increasing boost you also need to increase fuel so that you dont run a "lean mixture". from my understanding, the stock ecu will only let you boost to a certain point until it cuts fuel delivery, hence why you would need some kind of EM to override and compensate.
-randy
And most times you have to adjust timing. that's why a S-AFC is not a ideal solution for the EM of most modern EFI high performance autos.
Eric
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Originally posted by evodemon
since the evo is running rich at the higher end, would it be ok to keep the boost at ~19 psi?
since the evo is running rich at the higher end, would it be ok to keep the boost at ~19 psi?
That's not really true. The EVO computer was tuned out to run higher ing. Advance because, it tapers boost down at redline. So if you were to run higher boost you would need to take a little timing away so that the knock sensor would not pull to much timing. So you would have less performance with more boost because the computer pulled more timing then is need. Now the big problem that I see is that the factory knock sensor might not be dynamic enough to be able to determine at hi rpm engine nose or if it's really knock. This can be very damaging in the long run.
Stick with stock boost it’s high enough. If you were to lean it out a bit with a Super-AFC, it would be ok. (ono
The real way of doing things right is to have a true EM Solution. (Vishnu will be coming out with one very shortly)
Eric Lyublinsky
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Joined: Dec 2002
Posts: 171
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From: Frederick, MD
Originally posted by Eric Lyublinsky
That's not really true. The EVO computer was tuned out to run higher ing. Advance because, it tapers boost down at redline.
That's not really true. The EVO computer was tuned out to run higher ing. Advance because, it tapers boost down at redline.
The reason that "per pev" part is important is that as boost increases, airflow per rev increases as well, indexing into a different part of the table. So the ignition advance you get from the stock boost (which falls off in the upper RPM ranges) is the result of indexing to a particular part of the table. Since boost peaks and tapers by 4000 RPM, we know the table supports more airflow per rev than we're going to see in the upper RPM range. Less airflow due to less boost in higher RPMs results in significantly less airflow per rev. I suspect if you start indexing into higher airflow per rev entries, you'll get less ignition advance. In fact, I'm sure of it. That's exactly what the table typically does. Higher airflow per rev entries result in less ignition advance due to increased cylinder pressures.
All this goes out the window if you're using something like the XEDE piggyback to alter the airflow signal. So if you *just* use a boost controller to bump up the boost, I bet the ignition advance goes down accordingly.
Now the big problem that I see is that the factory knock sensor might not be dynamic enough to be able to determine at hi rpm engine nose or if it's really knock. This can be very damaging in the long run.
The real way of doing things right is to have a true EM Solution. (Vishnu will be coming out with one very shortly)
Thomas Dorris
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Joined: Jan 2003
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From: NR Reading PA
Ah...... don't feel bashful Tom. Everyone would like to know what is available to meet their performance needs and your DSM Link has a good reputation. Plus your a lot closer to me than Vishnu! 
Keep us informed on your plans and progress.
Speedlimit...........
Keep us informed on your plans and progress.
Speedlimit...........
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Originally posted by twdorris
That's possibly incorrect. Can we get some numbers to back it up? Here's what I'm getting at. The factory ECU uses a table indexed by RPM and airflow *per rev* of the motor to determine ignition timing. The Mitsu guys sit down with an engine dyno and spend LOTS of time tuning this three dimensional map for various conditions.
The reason that "per pev" part is important is that as boost increases, airflow per rev increases as well, indexing into a different part of the table. So the ignition advance you get from the stock boost (which falls off in the upper RPM ranges) is the result of indexing to a particular part of the table. Since boost peaks and tapers by 4000 RPM, we know the table supports more airflow per rev than we're going to see in the upper RPM range. Less airflow due to less boost in higher RPMs results in significantly less airflow per rev. I suspect if you start indexing into higher airflow per rev entries, you'll get less ignition advance. In fact, I'm sure of it. That's exactly what the table typically does. Higher airflow per rev entries result in less ignition advance due to increased cylinder pressures.
All this goes out the window if you're using something like the XEDE piggyback to alter the airflow signal. So if you *just* use a boost controller to bump up the boost, I bet the ignition advance goes down accordingly.
That's possibly incorrect. Can we get some numbers to back it up? Here's what I'm getting at. The factory ECU uses a table indexed by RPM and airflow *per rev* of the motor to determine ignition timing. The Mitsu guys sit down with an engine dyno and spend LOTS of time tuning this three dimensional map for various conditions.
The reason that "per pev" part is important is that as boost increases, airflow per rev increases as well, indexing into a different part of the table. So the ignition advance you get from the stock boost (which falls off in the upper RPM ranges) is the result of indexing to a particular part of the table. Since boost peaks and tapers by 4000 RPM, we know the table supports more airflow per rev than we're going to see in the upper RPM range. Less airflow due to less boost in higher RPMs results in significantly less airflow per rev. I suspect if you start indexing into higher airflow per rev entries, you'll get less ignition advance. In fact, I'm sure of it. That's exactly what the table typically does. Higher airflow per rev entries result in less ignition advance due to increased cylinder pressures.
All this goes out the window if you're using something like the XEDE piggyback to alter the airflow signal. So if you *just* use a boost controller to bump up the boost, I bet the ignition advance goes down accordingly.
Originally posted by twdorris
these commercials inserted into just about every post I see from you guys really bugs me. We're also developing a keen engine management piece for the EVO8, but I don't throw a reference to it in everything I post. Am I out of line here or is this acceptable practice on the evolutionm.net board? If it's acceptable, then I'll stop being so bothered by it.
Thomas Dorris
these commercials inserted into just about every post I see from you guys really bugs me. We're also developing a keen engine management piece for the EVO8, but I don't throw a reference to it in everything I post. Am I out of line here or is this acceptable practice on the evolutionm.net board? If it's acceptable, then I'll stop being so bothered by it.
Thomas Dorris
Originally posted by twdorris
That's possibly incorrect. Can we get some numbers to back it up? Here's what I'm getting at. The factory ECU uses a table indexed by RPM and airflow *per rev* of the motor to determine ignition timing. The Mitsu guys sit down with an engine dyno and spend LOTS of time tuning this three dimensional map for various conditions.
The reason that "per pev" part is important is that as boost increases, airflow per rev increases as well, indexing into a different part of the table. So the ignition advance you get from the stock boost (which falls off in the upper RPM ranges) is the result of indexing to a particular part of the table. Since boost peaks and tapers by 4000 RPM, we know the table supports more airflow per rev than we're going to see in the upper RPM range. Less airflow due to less boost in higher RPMs results in significantly less airflow per rev. I suspect if you start indexing into higher airflow per rev entries, you'll get less ignition advance. In fact, I'm sure of it. That's exactly what the table typically does. Higher airflow per rev entries result in less ignition advance due to increased cylinder pressures.
All this goes out the window if you're using something like the XEDE piggyback to alter the airflow signal. So if you *just* use a boost controller to bump up the boost, I bet the ignition advance goes down accordingly.
That's an interesting theory. Datalogging the raw knock sensor on a DSM shows the signal can be quite noisy indeed as RPMs increase, particularly as the motor ages. So noisy that there may not be enough room to accurately identify the anomolous knock spikes properly. I've not had any real problems with it, having driven 2 DSMs for almost 8 years now, but I can see how the theory might hold. Do you have evidence of this being a true problem?
OK, here's where my newbie status might be getting in the way. But to me, these commercials inserted into just about every post I see from you guys really bugs me. We're also developing a keen engine management piece for the EVO8, but I don't throw a reference to it in everything I post. Am I out of line here or is this acceptable practice on the evolutionm.net board? If it's acceptable, then I'll stop being so bothered by it.
Thomas Dorris
That's possibly incorrect. Can we get some numbers to back it up? Here's what I'm getting at. The factory ECU uses a table indexed by RPM and airflow *per rev* of the motor to determine ignition timing. The Mitsu guys sit down with an engine dyno and spend LOTS of time tuning this three dimensional map for various conditions.
The reason that "per pev" part is important is that as boost increases, airflow per rev increases as well, indexing into a different part of the table. So the ignition advance you get from the stock boost (which falls off in the upper RPM ranges) is the result of indexing to a particular part of the table. Since boost peaks and tapers by 4000 RPM, we know the table supports more airflow per rev than we're going to see in the upper RPM range. Less airflow due to less boost in higher RPMs results in significantly less airflow per rev. I suspect if you start indexing into higher airflow per rev entries, you'll get less ignition advance. In fact, I'm sure of it. That's exactly what the table typically does. Higher airflow per rev entries result in less ignition advance due to increased cylinder pressures.
All this goes out the window if you're using something like the XEDE piggyback to alter the airflow signal. So if you *just* use a boost controller to bump up the boost, I bet the ignition advance goes down accordingly.
That's an interesting theory. Datalogging the raw knock sensor on a DSM shows the signal can be quite noisy indeed as RPMs increase, particularly as the motor ages. So noisy that there may not be enough room to accurately identify the anomolous knock spikes properly. I've not had any real problems with it, having driven 2 DSMs for almost 8 years now, but I can see how the theory might hold. Do you have evidence of this being a true problem?
OK, here's where my newbie status might be getting in the way. But to me, these commercials inserted into just about every post I see from you guys really bugs me. We're also developing a keen engine management piece for the EVO8, but I don't throw a reference to it in everything I post. Am I out of line here or is this acceptable practice on the evolutionm.net board? If it's acceptable, then I'll stop being so bothered by it.
Thomas Dorris
Tom,
I really don't even retail the vishnu stuff just install it and I have tried all froms of EM on my REX and on other cars and I just feel they are the best in the biz for EM solution. But I don't know your product and if you can provide me a link I would love to read about it.
No I don't have any proof of the knock senser issue. Just knowing weekness in all OEM systems I just apley my .02.
See, all I'm trying to do is explain why just cranking up boost and leaning a car out is not the ideal for long tirm use. For the new folks to Turbo EFI cars. Even you I'm sure will agree.
Eric
Indeed. Tuners are welcome to post their products for sale in the LancerShopper or in their forum if they have one, but inserting these types of commercial messages in the technical forums is out of order, unless a question regarding a specific product is asked by a member. Which isnt the case here. [/B][/QUOTE],
Sorry, I will not do that again. I was just giving folks a idea of what's coming to the market that I feel is a true solution to there needs. I was not trying to sell products just going what I know and sharing my limited knowlage.
Eric Lyublinsky
Sorry, I will not do that again. I was just giving folks a idea of what's coming to the market that I feel is a true solution to there needs. I was not trying to sell products just going what I know and sharing my limited knowlage.
Eric Lyublinsky
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