ITB Dyno Session
04-13-12, 07:10 AM
#1
Rotary Freak
Thread Starter
ITB Dyno Session
We went to the dyno yesterday to run the car and get some numbers. It was extremely interesting. We started with the MAP that we ran in the car last September, but with the corrected timing. Since that time, I cleaned up a few air leaks and corrected the timing issues so that we had proper orientation. The casr would start and drive well so we were looking forward to it.
The first pull was a joke. The car bucked and snorted and wouldn't take full throttle. The Air Fuel, was showing lean spots where it was going to 17:1, YIIIKES!!!!! The WHP was a monster 91 and the torques were just over 80, LOL. We richened the whole Map by 10% and tried the second run. The car pulled a fair bit harder, but I could only use 3/4 throttle and it bucked at anything below 7,000, unless I breathed the throttle a lot. The second run, we didn't even get a decent pull as the bucking caused the tach signal to fall off the plug wire.
We looked at the Map and we decided to start by richening the bins above 5,000 rpm and throttle openings above 50%. We richened them up by another 10% and kept the same gradients. We ran a third pull and had to abort as somebody forgot to initiate the tracking, but the car felt better, but it still wouldn't take full throttle. So we took a stab at adding even more fuel in 4 bins where we extrapolated that we were at with 100% throttle and 4,000 to 7,000 rpm. We then ran our 4th pull.
The car ran a lot better and we still couldn't use 100 % throttle all the way up, but the car pulled strongly to 8,000 rpm in 4th. On this run, we got 191.8 rwhp and 167.2 ft.lbs of torque. There is still tons to do in the tuning, but we are totally pleased as the car is reacting properly to the tuning changes. It will pull hard to 9,000 rpm normally, so we have room. The last time we put the car on the dyno with the Holley, it pulled a 185.1 rwhp at 8,700 rpm, so we are looking okay with a lot more potential.
It really seems to like a lot more fuel than it used to and i think we can add some more timing as it still seems soft, but I am not certain that I want to go over 22 degrees. In a few of the bins we are up almost 20% from where we were and it still needs more as the more we add to it, the better it runs, but we were getting killed by the exhaust fumes. One interesting thing we found out was that the incar A/f wideband was showing wrong. We were showing way richer than the dyno operators sensor. We are now going to look at all the data and clean up the bins and go back. I cut a deal with the dyno shop and we can go back there when we need to at $100 an hour.
The car is running better and better all the time and I don't doubt we will be in the low 2teens rwhp, but it looks like we need a MAP to be like a turbo MAP under boost, LOL.
We will see after next time.
Eric
The first pull was a joke. The car bucked and snorted and wouldn't take full throttle. The Air Fuel, was showing lean spots where it was going to 17:1, YIIIKES!!!!! The WHP was a monster 91 and the torques were just over 80, LOL. We richened the whole Map by 10% and tried the second run. The car pulled a fair bit harder, but I could only use 3/4 throttle and it bucked at anything below 7,000, unless I breathed the throttle a lot. The second run, we didn't even get a decent pull as the bucking caused the tach signal to fall off the plug wire.
We looked at the Map and we decided to start by richening the bins above 5,000 rpm and throttle openings above 50%. We richened them up by another 10% and kept the same gradients. We ran a third pull and had to abort as somebody forgot to initiate the tracking, but the car felt better, but it still wouldn't take full throttle. So we took a stab at adding even more fuel in 4 bins where we extrapolated that we were at with 100% throttle and 4,000 to 7,000 rpm. We then ran our 4th pull.
The car ran a lot better and we still couldn't use 100 % throttle all the way up, but the car pulled strongly to 8,000 rpm in 4th. On this run, we got 191.8 rwhp and 167.2 ft.lbs of torque. There is still tons to do in the tuning, but we are totally pleased as the car is reacting properly to the tuning changes. It will pull hard to 9,000 rpm normally, so we have room. The last time we put the car on the dyno with the Holley, it pulled a 185.1 rwhp at 8,700 rpm, so we are looking okay with a lot more potential.
It really seems to like a lot more fuel than it used to and i think we can add some more timing as it still seems soft, but I am not certain that I want to go over 22 degrees. In a few of the bins we are up almost 20% from where we were and it still needs more as the more we add to it, the better it runs, but we were getting killed by the exhaust fumes. One interesting thing we found out was that the incar A/f wideband was showing wrong. We were showing way richer than the dyno operators sensor. We are now going to look at all the data and clean up the bins and go back. I cut a deal with the dyno shop and we can go back there when we need to at $100 an hour.
The car is running better and better all the time and I don't doubt we will be in the low 2teens rwhp, but it looks like we need a MAP to be like a turbo MAP under boost, LOL.
We will see after next time.
Eric
04-13-12, 10:52 AM
#2
I've found that an in-car wideband sensor is often more accurate than a backprobe often used at a dyno. If the backprobe is mounted correctly and is attached to a vaccuum source and if you've got no exhaust leaks measurements are very close, but if anything is the slightest bit off a backprobe will read lean.
Sounds like your car needs a good tune, when starting from scratch like you I don't tune by making dyno runs and making modifications to the map, I Just get the car running in a certain point on the map, keep it steady at that point using the dynos brake and modify injection time untill a/f is close and move on. When I find that lots of tweaking is needed I modify a big part of the map at once. Mapping a car from scratch properly takes some dyno time, definetly more than a few runs. But it sounds like your on the right track, looking forward to the ending result!
Sounds like your car needs a good tune, when starting from scratch like you I don't tune by making dyno runs and making modifications to the map, I Just get the car running in a certain point on the map, keep it steady at that point using the dynos brake and modify injection time untill a/f is close and move on. When I find that lots of tweaking is needed I modify a big part of the map at once. Mapping a car from scratch properly takes some dyno time, definetly more than a few runs. But it sounds like your on the right track, looking forward to the ending result!
Last edited by John Huijben; 04-13-12 at 10:57 AM.
04-13-12, 12:57 PM
#3
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tuning the PP has taught me that if you just give the engine what it wants, you and it will both be happy. my full throttle mixture is in the mid 11's, the plugs come out a little dark, so its rich, but not hugely so.
my advise would be to tune the mixture for power, and the AFR number is there to make sure its consistent and stuff
but 190+ rwhp is good! keep going. actually you should leave it a little rich, to be safe and try 20 degrees of timing, and then maybe 24, and see what it wants. at the very least you can get a feel for the way the engine responds to timing changes.
my advise would be to tune the mixture for power, and the AFR number is there to make sure its consistent and stuff
but 190+ rwhp is good! keep going. actually you should leave it a little rich, to be safe and try 20 degrees of timing, and then maybe 24, and see what it wants. at the very least you can get a feel for the way the engine responds to timing changes.
04-13-12, 02:10 PM
#4
Rotary Freak
Thread Starter
Great advice and thanks. We just ran a simulated MAP on the Megatune and it is showing that we need to boost A/F's even more. It seems that last year we were only getting about 65% VE and this year, somewhere close to 90%.
Air Fuels in the 11:1 range!!!! That will make my Race Engineer happy to hear that as he believed we needed to be in the low 12's all along to make this motor happy. We are just brewing up the new MAPS and I can hardly wait to get back to the dyno and try them. I amy delay my business trip next week to squeeze in some more time to try these ideas.
Eric
Air Fuels in the 11:1 range!!!! That will make my Race Engineer happy to hear that as he believed we needed to be in the low 12's all along to make this motor happy. We are just brewing up the new MAPS and I can hardly wait to get back to the dyno and try them. I amy delay my business trip next week to squeeze in some more time to try these ideas.
Eric
04-13-12, 07:10 PM
#5
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that's when you know you're doing it right! when you quit work 
i played with a range of jets with mine, and i know i loose power going richer, and it makes more going leaner, but the next jet leaner from mid 11's gave me a 12.8:1, which is leaner than i'd like, so i left it in the 11's.
however two track days in, it runs great, doesn't smoke, the plugs look good, the tailpipe looks good, its giving me every sign that its happy.
so the takeaway is not to hang your hat on just the AFR number, you wanna look at other things too
i played with a range of jets with mine, and i know i loose power going richer, and it makes more going leaner, but the next jet leaner from mid 11's gave me a 12.8:1, which is leaner than i'd like, so i left it in the 11's.
however two track days in, it runs great, doesn't smoke, the plugs look good, the tailpipe looks good, its giving me every sign that its happy.
so the takeaway is not to hang your hat on just the AFR number, you wanna look at other things too
04-13-12, 11:55 PM
#6
that's when you know you're doing it right! when you quit work
i played with a range of jets with mine, and i know i loose power going richer, and it makes more going leaner, but the next jet leaner from mid 11's gave me a 12.8:1, which is leaner than i'd like, so i left it in the 11's.
however two track days in, it runs great, doesn't smoke, the plugs look good, the tailpipe looks good, its giving me every sign that its happy.
so the takeaway is not to hang your hat on just the AFR number, you wanna look at other things too
i played with a range of jets with mine, and i know i loose power going richer, and it makes more going leaner, but the next jet leaner from mid 11's gave me a 12.8:1, which is leaner than i'd like, so i left it in the 11's.
however two track days in, it runs great, doesn't smoke, the plugs look good, the tailpipe looks good, its giving me every sign that its happy.
so the takeaway is not to hang your hat on just the AFR number, you wanna look at other things too
You do know that Logan is running high 12's to lower 13 afr in his semi pp right? NA rotary's are a little more forgiving than we give them credit for.
04-14-12, 12:40 PM
#7
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my only hesitation to run that lean on the track is that A) i have a weber, so i have to have some margin for things like bumps in a turn, and other lean spots and B) i wonder what his EGT's look like? or more to the point i wonder what MY EGT's would look like @13:1.
the next step for my car is actually to go and build a new exhaust on the dyno, and then build/buy a better air cleaner
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04-14-12, 04:59 PM
#8
Old [Sch|F]ool
Air/fuel ratio really doesn't seem to make much of a difference power-wise. Either I'm far off the mark enough that I'm not in the sweet spot, but I've seen basically no change between ~11.8:1 and 13:1, power-wise. I've also, pre-wideband, run so lean at the track that the spark plugs were bone while and the ground electrodes partially melted, added fuel, and saw very little change in power output. Spark plug life, however, was much better
Noodle-baker: I run to the rich side to keep things cooler. Cooler engine and cooler combustion means cooler EGTs, which also means different exhaust tuning effects. How much of noted power changes with different air/fuel ratios are the result of better combustion, and how much are the result of changing the exhaust tuning via the temperature change?
Fascinating topic.
Anyway, with widebands, it's easy to get a wrong reading. I've seen two widebands in the same car mounted 20 inches from each other read a full ratio difference - the car said 12:1 and the dyno wideband said 13:1. Which do you trust?
Also - ignore any readings if it is misfiring at all. My half-bridge will show 15-16:1 sometimes while in the brap zone, spikes dead lean when shifting (ignition cut - engine is still getting 12:1) They don't truly read air/fuel ratio, they read the oxygen content of the exhaust.
Also - When you say you are changing your MAP - are you changing the Manifold Absolute Pressure sensor or are you changing the fuel map?
04-14-12, 06:05 PM
#9
Rotary Freak
Thread Starter
We are only working with the ignition and fuel maps. We are finding that after cleaning up some nagging issues after last year and finally figuring out the detonation problem, that the car needs entirely new fuel levels. Lasdt year it would pull hard at wide open throttle with the fuels in the 58 range. We are now almost up to 70 and it still wants more to run clean. For now, I am ignoring the O2 sensor as I am not sure it is accurate. I am going by old school techniques like reading the plugs and how hard it pulls. The big issue is that I can't drive this car on the street, so we are limited to running it on track or on a dyno. On track the driver seems to drive around fueling issues and makes the car work. On the dyno there is no faking it and the problems are there and very evident. If I could drive this thing around on the street for a while, I would be able to quickly dial it in.
Interestingly, when we went back to the Megatune and had the software create a fuel MAP for us, if we put in 65% Volumetric Efficiency, we get fuel bin numbers like we were running. Now that we seem to need to be in the low 80's or high 70's, it is indicating that we are approaching 90% VE. This is why we are pushing to get this right. I think that we should be able to get a reliable 210 rwhp out of this 1/2 bridge.
I just need more tuning time and less real life.........
Eric
Interestingly, when we went back to the Megatune and had the software create a fuel MAP for us, if we put in 65% Volumetric Efficiency, we get fuel bin numbers like we were running. Now that we seem to need to be in the low 80's or high 70's, it is indicating that we are approaching 90% VE. This is why we are pushing to get this right. I think that we should be able to get a reliable 210 rwhp out of this 1/2 bridge.
I just need more tuning time and less real life.........
Eric
04-14-12, 08:34 PM
#10
Old [Sch|F]ool
I wonder if your injector constant or dead time are right. The map bins reflect the VE of the engine and a stoichiometric mixture. Enrichment will therefore have map bins much higher than the engine's true VE. 10% more fuel over stoich will be reflected as 10% higher number than the actual VE.
For instance, my map has 58 as the bin for WOT at 1000rpm. It's 85 at 2900, 97/95 at the plateau of the torque curve, and my engine doesn't make anywhere near the torque (aka, have the volumetric efficiency) that your engine will. IIRC peak torque was 124ft-lb at the wheels on a DynoJet.
For instance, my map has 58 as the bin for WOT at 1000rpm. It's 85 at 2900, 97/95 at the plateau of the torque curve, and my engine doesn't make anywhere near the torque (aka, have the volumetric efficiency) that your engine will. IIRC peak torque was 124ft-lb at the wheels on a DynoJet.
05-22-12, 08:35 AM
#11
Rotary Freak
Thread Starter
Very, very interesting results from my last test day on track. We started the day with the fuel Map set where we thought it should be based on the test results from the dyno run and with what ran okay on the dyno. The car started and pulled out on to the track then would pull anything beyond 1/8th throttle. It would pull up to 8,500 rpm easily with that throttle opening, but it just died away. We were still below what the Megatune predicted map was, so we added a bit more fuel in the upper bins and things got worse.
We sat back and scratched our heads and decided to go back to the MAP that worked well at Mosport last fall, but induced detonation. It was substantially leaner than having bins at full throttle in the high 80's, we were closer to the high 60's low 70's. Went out with that and huge improvement. Some stagger when I transitioned the throttle, so I came in and we trimmed the Accel shot back leaner as well. Again a strong improvement and the car was pulling hard and flexible. Still a bit soft, but we wanted to get some time in on the setup and see if that made any difference. I ran about 20 minutes on the setup and the car changed some. The engine note got crisper (sort of a hard rythmic pop)and we picked up a bridge port lope again at idle. The exhaust pulses grew harder and you could feel the exhaust pulse about 6 feet from the end of the exhaust.
I decided that it was running well enough to try some gonzo laps and the car ran great. Consistent in every way, stable oil temps and water temps, would pull easily to over 9,000 rpm again and full throttle runs were great. It was running well enough that I started to get some fuel pickup issues in right hand corners again. After I ran it very hard for about 20 minutes, I came in left the car idling and we put in another guy to drive the car for another 30 minutes. He was only running the car to 8,000 and it did that with no issues.
Soooooo, at the end of the day, we are about 10 to 15% leaner than Megatune predicted and what the dyno runs were indicating. We have to lean out a few of the mid range bins to improve mid range response and torque. I have to improve my fuel pick up system and we are going to start messing about with the timing some. We are running 22 degrees everywhere, but we think that the motor wants a some more at lower rpm and maybe a degree or two at higher rpms.
Very pleased and happy in that the car is working great, is repeatable/consistent, it starts, idles and shuts off like a street car. And can catch and pull past aa early 2000 - 2004 911 on the straights at this track in second and third. We were almost as quick as some tuned TII FC's in a straight line, but they could torque me coming out of the very tight corners and I could catch them at top end due to my RPM range and gearing.
Just thought you guys would like to know that the 4 ITB setup is working very well now. We now have to try it on the longer straights at Mosport.
Eric
We sat back and scratched our heads and decided to go back to the MAP that worked well at Mosport last fall, but induced detonation. It was substantially leaner than having bins at full throttle in the high 80's, we were closer to the high 60's low 70's. Went out with that and huge improvement. Some stagger when I transitioned the throttle, so I came in and we trimmed the Accel shot back leaner as well. Again a strong improvement and the car was pulling hard and flexible. Still a bit soft, but we wanted to get some time in on the setup and see if that made any difference. I ran about 20 minutes on the setup and the car changed some. The engine note got crisper (sort of a hard rythmic pop)and we picked up a bridge port lope again at idle. The exhaust pulses grew harder and you could feel the exhaust pulse about 6 feet from the end of the exhaust.
I decided that it was running well enough to try some gonzo laps and the car ran great. Consistent in every way, stable oil temps and water temps, would pull easily to over 9,000 rpm again and full throttle runs were great. It was running well enough that I started to get some fuel pickup issues in right hand corners again. After I ran it very hard for about 20 minutes, I came in left the car idling and we put in another guy to drive the car for another 30 minutes. He was only running the car to 8,000 and it did that with no issues.
Soooooo, at the end of the day, we are about 10 to 15% leaner than Megatune predicted and what the dyno runs were indicating. We have to lean out a few of the mid range bins to improve mid range response and torque. I have to improve my fuel pick up system and we are going to start messing about with the timing some. We are running 22 degrees everywhere, but we think that the motor wants a some more at lower rpm and maybe a degree or two at higher rpms.
Very pleased and happy in that the car is working great, is repeatable/consistent, it starts, idles and shuts off like a street car. And can catch and pull past aa early 2000 - 2004 911 on the straights at this track in second and third. We were almost as quick as some tuned TII FC's in a straight line, but they could torque me coming out of the very tight corners and I could catch them at top end due to my RPM range and gearing.
Just thought you guys would like to know that the 4 ITB setup is working very well now. We now have to try it on the longer straights at Mosport.
Eric
06-11-12, 05:19 AM
#14
dont be scared to lean it up,we run 290whp/10200rpm pp's as high as 14.3 afr's and still safe on the plug,tune it with the plugs and as someone mentioned use the afrs to keep the tune consistant
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Westcoast FC (05-12-21)
06-11-12, 10:53 AM
#15
Rotary Freak
Thread Starter
Thanks, that is what I am starting to believe as well. Leaner makes more power as long as you don't go into detonation. I just need to move the WB O2 bung down further on the pipe after the merge to get an accurate reading.
It is shocking how many tuning tricks from my 2 stroke kart days are being repeated with this motor.
Eric
It is shocking how many tuning tricks from my 2 stroke kart days are being repeated with this motor.
Eric
07-03-12, 09:15 AM
#17
Rotary Freak
Thread Starter
When I get a chance. Just got back from a long business trip. Need to finish off the cold air box and move the Wide band bung down the pipe to after where the 2 pipes merge so that it is finally useful and accurate again. Next week I am away again, but I should have time after the 13th of July to get working on it again.
Gawd, my life is soooooo busy.
Eric
Gawd, my life is soooooo busy.
Eric
11-26-12, 01:31 AM
#20
Vintage sportcars
Hello,
that sounds good, what engine configuration are you running besides the ITBs ?
I have a raceported (big streetport) 6 port motor with ceramics and lightened/balanced rotating assembly, that will be run with ITBs and defined autoworks header.
Interesting thing, I run the high comp 9.7:1 rotors with FD housings, I have to play with the timing later when the fuel is sortet out but I would be interested what timing you would run on that motor. I was guessing around 25 degrees should be close. For startup and breakin which will be done when everything is installed I lock the timing to 5 deg leading & trailing and see what happens.
Many thanks
Steven
that sounds good, what engine configuration are you running besides the ITBs ?
I have a raceported (big streetport) 6 port motor with ceramics and lightened/balanced rotating assembly, that will be run with ITBs and defined autoworks header.
Interesting thing, I run the high comp 9.7:1 rotors with FD housings, I have to play with the timing later when the fuel is sortet out but I would be interested what timing you would run on that motor. I was guessing around 25 degrees should be close. For startup and breakin which will be done when everything is installed I lock the timing to 5 deg leading & trailing and see what happens.
Many thanks
Steven
11-26-12, 07:36 AM
#21
Rotary Freak
Thread Starter
Hello,
that sounds good, what engine configuration are you running besides the ITBs ?
I have a raceported (big streetport) 6 port motor with ceramics and lightened/balanced rotating assembly, that will be run with ITBs and defined autoworks header.
Interesting thing, I run the high comp 9.7:1 rotors with FD housings, I have to play with the timing later when the fuel is sortet out but I would be interested what timing you would run on that motor. I was guessing around 25 degrees should be close. For startup and breakin which will be done when everything is installed I lock the timing to 5 deg leading & trailing and see what happens.
Many thanks
Steven
that sounds good, what engine configuration are you running besides the ITBs ?
I have a raceported (big streetport) 6 port motor with ceramics and lightened/balanced rotating assembly, that will be run with ITBs and defined autoworks header.
Interesting thing, I run the high comp 9.7:1 rotors with FD housings, I have to play with the timing later when the fuel is sortet out but I would be interested what timing you would run on that motor. I was guessing around 25 degrees should be close. For startup and breakin which will be done when everything is installed I lock the timing to 5 deg leading & trailing and see what happens.
Many thanks
Steven
Timing wise, we have settled on 25 degrees as well and oddly enough it works best on that, though it did pull really hard at lower rpm's when we had it up to 29 degrees, but suffered detonation up top.
The car works great right now, I just haven't had the time to get to a dyno and I have to do this before next season as the series I am going to be racing in is a Power to Weight series and I need to set a baseline. I am going to have a decent local tuner go through the car next spring, but he wants to do this on-track so I may have decent numbers by then.
The ITB system has great response and makes good power. We did have to go to an ALpha N style metering as there isn't a consistent enough vacuum sugnal to run any other way.
Regards,
Eric
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Westcoast FC (05-12-21)
11-26-12, 11:32 AM
#22
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if you want a "safe" timing map, idle can be -5 to 5 BTDC L, then just have it slowly advance to 15-18 BTDC L by about 2000-2500rpm, use a 15 degree timing split and call it good.
or you can lock the timing from 10-20 BTDC L, like the competition book. the idle is rough, but over that it works fine
11-27-12, 02:24 AM
#23
Vintage sportcars
Oh, that was fast. Thanks for the answers, Eric and j9fd3s.
Your setup really is interesting. I like the ITBs, I never drove such a motor but that sounds like fun. Response should be instantly. And of course the sound
Thats interesting, so 29 degrees at low rpms, which is quite a lot as far as I am informed. I guess you are running LBT around 12.5 to 13.5 AFR in this area to make this possible ? If I recall correctly, the fastest flame speed will occur at around 11.0 AFR. (But don't quote me on that, I am typing from memory here) So going leaner than 11 will allow for more timing and should make more power
My tuner recommended 13.5 AFR for WOT conditions for my particular setup. I think thats a good value and I will stick to that and set the timing according. I will maybe try to get the same AFR for mid to low rpms and see what happens. Interesting stuff
By the way what ecu are you using ?
@j9fd3s
Yes, I did choose the 5 degs to get it started and sort out the basic fuel setup and verify everything works fine before progressing anything further. For the first roll out I will most likely set it to something simple like you mentioned. Keeping it simple, no IAT, CTS correction and acceleration enrichment so I can work on the raw base fuel. I tried to arrange a dyno session on a local subaru tuners shop, they are well known in our region and are like 5 mins away, but they are too ***** to let an RX7 use it ... Forces me to find someone in germany who is more willing to accept my cash ...
Actually what makes me sad is that tuning is not well known in luxembourg, when you speak tuning everyone referrs it to big wheels and stereos lol. No use trying to talk about AFR or timing, or even a standalone ecu (omg whats that
how many ponnys does it add ?) only thing I am getting is funny looks and stupid comments. Thats how retarded tuning is in luxemburg with exception of a few pros who keep it to themselfes.
Steven
Your setup really is interesting. I like the ITBs, I never drove such a motor but that sounds like fun. Response should be instantly. And of course the sound
My tuner recommended 13.5 AFR for WOT conditions for my particular setup. I think thats a good value and I will stick to that and set the timing according. I will maybe try to get the same AFR for mid to low rpms and see what happens. Interesting stuff
By the way what ecu are you using ?@j9fd3s
Yes, I did choose the 5 degs to get it started and sort out the basic fuel setup and verify everything works fine before progressing anything further. For the first roll out I will most likely set it to something simple like you mentioned. Keeping it simple, no IAT, CTS correction and acceleration enrichment so I can work on the raw base fuel. I tried to arrange a dyno session on a local subaru tuners shop, they are well known in our region and are like 5 mins away, but they are too ***** to let an RX7 use it ... Forces me to find someone in germany who is more willing to accept my cash ...
Actually what makes me sad is that tuning is not well known in luxembourg, when you speak tuning everyone referrs it to big wheels and stereos lol. No use trying to talk about AFR or timing, or even a standalone ecu (omg whats that
how many ponnys does it add ?) only thing I am getting is funny looks and stupid comments. Thats how retarded tuning is in luxemburg with exception of a few pros who keep it to themselfes. Steven
11-27-12, 12:16 PM
#24
Rotary Freak
Thread Starter
Oh, that was fast. Thanks for the answers, Eric and j9fd3s.
Your setup really is interesting. I like the ITBs, I never drove such a motor but that sounds like fun. Response should be instantly. And of course the sound
Thats interesting, so 29 degrees at low rpms, which is quite a lot as far as I am informed. I guess you are running LBT around 12.5 to 13.5 AFR in this area to make this possible ? If I recall correctly, the fastest flame speed will occur at around 11.0 AFR. (But don't quote me on that, I am typing from memory here) So going leaner than 11 will allow for more timing and should make more power
My tuner recommended 13.5 AFR for WOT conditions for my particular setup. I think thats a good value and I will stick to that and set the timing according. I will maybe try to get the same AFR for mid to low rpms and see what happens. Interesting stuff By the way what ecu are you using ?
@j9fd3s
Yes, I did choose the 5 degs to get it started and sort out the basic fuel setup and verify everything works fine before progressing anything further. For the first roll out I will most likely set it to something simple like you mentioned. Keeping it simple, no IAT, CTS correction and acceleration enrichment so I can work on the raw base fuel. I tried to arrange a dyno session on a local subaru tuners shop, they are well known in our region and are like 5 mins away, but they are too ***** to let an RX7 use it ... Forces me to find someone in germany who is more willing to accept my cash ...
Actually what makes me sad is that tuning is not well known in luxembourg, when you speak tuning everyone referrs it to big wheels and stereos lol. No use trying to talk about AFR or timing, or even a standalone ecu (omg whats that how many ponnys does it add ?) only thing I am getting is funny looks and stupid comments. Thats how retarded tuning is in luxemburg with exception of a few pros who keep it to themselfes.
Steven
Your setup really is interesting. I like the ITBs, I never drove such a motor but that sounds like fun. Response should be instantly. And of course the sound
Thats interesting, so 29 degrees at low rpms, which is quite a lot as far as I am informed. I guess you are running LBT around 12.5 to 13.5 AFR in this area to make this possible ? If I recall correctly, the fastest flame speed will occur at around 11.0 AFR. (But don't quote me on that, I am typing from memory here) So going leaner than 11 will allow for more timing and should make more power
My tuner recommended 13.5 AFR for WOT conditions for my particular setup. I think thats a good value and I will stick to that and set the timing according. I will maybe try to get the same AFR for mid to low rpms and see what happens. Interesting stuff
By the way what ecu are you using ?@j9fd3s
Yes, I did choose the 5 degs to get it started and sort out the basic fuel setup and verify everything works fine before progressing anything further. For the first roll out I will most likely set it to something simple like you mentioned. Keeping it simple, no IAT, CTS correction and acceleration enrichment so I can work on the raw base fuel. I tried to arrange a dyno session on a local subaru tuners shop, they are well known in our region and are like 5 mins away, but they are too ***** to let an RX7 use it ... Forces me to find someone in germany who is more willing to accept my cash ...
Actually what makes me sad is that tuning is not well known in luxembourg, when you speak tuning everyone referrs it to big wheels and stereos lol. No use trying to talk about AFR or timing, or even a standalone ecu (omg whats that
how many ponnys does it add ?) only thing I am getting is funny looks and stupid comments. Thats how retarded tuning is in luxemburg with exception of a few pros who keep it to themselfes. Steven
It is interesting that after you play with stuff for a while, you end up drifting back to the Racing Beat suggestions for timing and air fuels. Maybe they did know something.
Next spring I am going to try to advance the timing at lower rpms again as it really did help with bottom end power in lower gears (like 1st and 2nd).
Eric
11-27-12, 01:39 PM
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Your setup really is interesting. I like the ITBs, I never drove such a motor but that sounds like fun. Response should be instantly. And of course the sound
Thats interesting, so 29 degrees at low rpms, which is quite a lot as far as I am informed. I guess you are running LBT around 12.5 to 13.5 AFR in this area to make this possible ? If I recall correctly, the fastest flame speed will occur at around 11.0 AFR. (But don't quote me on that, I am typing from memory here) So going leaner than 11 will allow for more timing and should make more power
My tuner recommended 13.5 AFR for WOT conditions for my particular setup. I think thats a good value and I will stick to that and set the timing according. I will maybe try to get the same AFR for mid to low rpms and see what happens. Interesting stuff By the way what ecu are you using ?
@j9fd3s
Yes, I did choose the 5 degs to get it started and sort out the basic fuel setup and verify everything works fine before progressing anything further. For the first roll out I will most likely set it to something simple like you mentioned. Keeping it simple, no IAT, CTS correction and acceleration enrichment so I can work on the raw base fuel. I tried to arrange a dyno session on a local subaru tuners shop, they are well known in our region and are like 5 mins away, but they are too ***** to let an RX7 use it ... Forces me to find someone in germany who is more willing to accept my cash ...
Actually what makes me sad is that tuning is not well known in luxembourg, when you speak tuning everyone referrs it to big wheels and stereos lol. No use trying to talk about AFR or timing, or even a standalone ecu (omg whats that how many ponnys does it add ?) only thing I am getting is funny looks and stupid comments. Thats how retarded tuning is in luxemburg with exception of a few pros who keep it to themselfes.
Steven
Thats interesting, so 29 degrees at low rpms, which is quite a lot as far as I am informed. I guess you are running LBT around 12.5 to 13.5 AFR in this area to make this possible ? If I recall correctly, the fastest flame speed will occur at around 11.0 AFR. (But don't quote me on that, I am typing from memory here) So going leaner than 11 will allow for more timing and should make more power
My tuner recommended 13.5 AFR for WOT conditions for my particular setup. I think thats a good value and I will stick to that and set the timing according. I will maybe try to get the same AFR for mid to low rpms and see what happens. Interesting stuff
By the way what ecu are you using ?@j9fd3s
Yes, I did choose the 5 degs to get it started and sort out the basic fuel setup and verify everything works fine before progressing anything further. For the first roll out I will most likely set it to something simple like you mentioned. Keeping it simple, no IAT, CTS correction and acceleration enrichment so I can work on the raw base fuel. I tried to arrange a dyno session on a local subaru tuners shop, they are well known in our region and are like 5 mins away, but they are too ***** to let an RX7 use it ... Forces me to find someone in germany who is more willing to accept my cash ...
Actually what makes me sad is that tuning is not well known in luxembourg, when you speak tuning everyone referrs it to big wheels and stereos lol. No use trying to talk about AFR or timing, or even a standalone ecu (omg whats that
how many ponnys does it add ?) only thing I am getting is funny looks and stupid comments. Thats how retarded tuning is in luxemburg with exception of a few pros who keep it to themselfes. Steven
if you're not trying to get 101% of the power out of the engine, tuning an NA is really simple, you find out what the engine wants and then go a little richer.
nobody knows about tuning here either, we've actually got a car commercial where some camry "owners" are telling how sporty the car is because its grounded to the ground. the P port is almost everything a car SHOULD be, its just FUN to drive. new cars have this trend toward having literally a flat torque curve, and this makes for a really BORING driving experience. the P port (or rotaries in general) are fun because the torque curve goes UP with revs. this is a little detail we miss in most conversation, its very easy to quote big hp numbers, but the way the hp is delivered is where the fun is.