installed mtune
#1
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installed mtune
I received my mtune on Sat. Spend Sunday installing. Fairly straight forward install. I had one issue where my car would not start after the install. After talking with Joshua and pending some time here, I realized that the little box I disconnected under the passenger kickboard was the alarm brain, and that the car will not fire without that plugged in (or jumpered).
Once I plugged that in, the car fired right up. Once warm my wb02 reads ~15 afr. at idle (18hg of vac) (running premium 93octaine)
Only issue I have currently is that when I blip the throttle up to ~3k, the rpm's come down to about 2k and hover, then slowly come back down to 900 idle. I have not reset my idle yet (tonights task).
This is a pure track car, so I cannot really drive it around yet. Hopefully will get it to the track this weekend to test and tune.
Once I plugged that in, the car fired right up. Once warm my wb02 reads ~15 afr. at idle (18hg of vac) (running premium 93octaine)
Only issue I have currently is that when I blip the throttle up to ~3k, the rpm's come down to about 2k and hover, then slowly come back down to 900 idle. I have not reset my idle yet (tonights task).
This is a pure track car, so I cannot really drive it around yet. Hopefully will get it to the track this weekend to test and tune.
#3
I installed mine 2 weekends ago and am pretty impressed with the improvement, even over the A-Tune. Part throttle and low boost stuff, the car *really* shines, but even at WOT the car seems to run a LOT better. Holds boost a little longer and just seems more willing to rev. Overall a much flatter power curve. And it takes a lot less throttle to rev-match - it's just a lot more responsive. (Heel/toe previously took a pretty healthy stab of the throttle pedal... now just a quick tap is enough.)
#4
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Resetting the idle to ~850 will fix that.
I installed mine 2 weekends ago and am pretty impressed with the improvement, even over the A-Tune. Part throttle and low boost stuff, the car *really* shines, but even at WOT the car seems to run a LOT better. Holds boost a little longer and just seems more willing to rev. Overall a much flatter power curve. And it takes a lot less throttle to rev-match - it's just a lot more responsive. (Heel/toe previously took a pretty healthy stab of the throttle pedal... now just a quick tap is enough.)
I installed mine 2 weekends ago and am pretty impressed with the improvement, even over the A-Tune. Part throttle and low boost stuff, the car *really* shines, but even at WOT the car seems to run a LOT better. Holds boost a little longer and just seems more willing to rev. Overall a much flatter power curve. And it takes a lot less throttle to rev-match - it's just a lot more responsive. (Heel/toe previously took a pretty healthy stab of the throttle pedal... now just a quick tap is enough.)
I barley got to drive this car without mtune. I've spent the last 6 months rebuilding it and making it track worthy again. It was a lot bigger task that I had intended when I bought the car. Mtune was just the best way for me to get the car tuned correctly by someone who knew what they were doing. Otherwise I had an old maf setup and it was up to me to figure out what af ratios I wanted and how to set them
#5
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The 2,000 rpm hold is by design per Joshua. I don't recall the technical reason for it, but you aren't going to make it go away by resetting the idle.
#6
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I played with the idle screw a bit tonight, and it did not change the idle much (did not bypass the icv yet). I could not actually get the car to idle down to 850. it would only go down to ~1000, and bounce between 1000 and 1100 or so. My af's seem a little on the lean side mid-high 15 at idle. I have an adjustable fpr, and have it set to 3 bar (using a fuel pressure gauge).
I'm assuming each one of these cars might be slightly different and might need some of their own tweeks?
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#8
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I can't really, all I can tell you is that it's there by design for some reason. It may not be present in all revisions (there have been a few since release), but it's in the latest. Maybe Joshua will jump in and explain its exact purpose.
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really? ok. I guess it should not matter to me, being a track car and all, but it seems like it would be a bit annoying on a street car.
I played with the idle screw a bit tonight, and it did not change the idle much (did not bypass the icv yet). I could not actually get the car to idle down to 850. it would only go down to ~1000, and bounce between 1000 and 1100 or so. My af's seem a little on the lean side mid-high 15 at idle. I have an adjustable fpr, and have it set to 3 bar (using a fuel pressure gauge).
I'm assuming each one of these cars might be slightly different and might need some of their own tweeks?
I played with the idle screw a bit tonight, and it did not change the idle much (did not bypass the icv yet). I could not actually get the car to idle down to 850. it would only go down to ~1000, and bounce between 1000 and 1100 or so. My af's seem a little on the lean side mid-high 15 at idle. I have an adjustable fpr, and have it set to 3 bar (using a fuel pressure gauge).
I'm assuming each one of these cars might be slightly different and might need some of their own tweeks?
#10
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when I rev the engine to say 3k. instead of having the rpm's fall off naturally till they get to idle, the revs stick at ~2k for a second or two, then slowly come back down to idle.
I have a brand new icv in my car, and it did not do this before mtune.
I have a brand new icv in my car, and it did not do this before mtune.
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Mine has a couple other odd issues related to a somewhat flaky TPS. it's adjusted and tests properly, but I think it's got some dead spots and/or doesn't always close the idle circuit when hot. I'm going to pull it this weekend and see about cleaning it out, or I've got a spare I may test and swap in.
#12
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I get pretty damn good vac readings. 18in mg once warm. ill do the proper reset tomorrow and see how it goes.
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Yep, the slowing engine decel at ~2000rpm is right when the DME turns back on the injectors. The new software it should have a slight hold there and then decel slowly back to idle (850rpm in the latest software).
Some engines (such as mine), have a lightened flywheel/clutch/PP and have more of an issue with drop-throttle stalling. So I added in some 'help', to prevent that.
Earlier software, we bumped the idle speed up, so that it had more hp/tq to catch and prevent drop-throttle stalling. But many users wanted a more normal idle speed. Fine, so in this case we need to be a bit more aggressive in slowing the engine decel rate before it gets to idle.
It really shouldn't be very noticeable when driving. And, in-fact, nearly every new car does something similar. If it is a big deal, I can reduce the affect, and perhaps I will regardless for the update.
Some engines (such as mine), have a lightened flywheel/clutch/PP and have more of an issue with drop-throttle stalling. So I added in some 'help', to prevent that.
Earlier software, we bumped the idle speed up, so that it had more hp/tq to catch and prevent drop-throttle stalling. But many users wanted a more normal idle speed. Fine, so in this case we need to be a bit more aggressive in slowing the engine decel rate before it gets to idle.
It really shouldn't be very noticeable when driving. And, in-fact, nearly every new car does something similar. If it is a big deal, I can reduce the affect, and perhaps I will regardless for the update.
#14
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Yep, the slowing engine decel at ~2000rpm is right when the DME turns back on the injectors. The new software it should have a slight hold there and then decel slowly back to idle (850rpm in the latest software).
Some engines (such as mine), have a lightened flywheel/clutch/PP and have more of an issue with drop-throttle stalling. So I added in some 'help', to prevent that.
Earlier software, we bumped the idle speed up, so that it had more hp/tq to catch and prevent drop-throttle stalling. But many users wanted a more normal idle speed. Fine, so in this case we need to be a bit more aggressive in slowing the engine decel rate before it gets to idle.
It really shouldn't be very noticeable when driving. And, in-fact, nearly every new car does something similar. If it is a big deal, I can reduce the affect, and perhaps I will regardless for the update.
Some engines (such as mine), have a lightened flywheel/clutch/PP and have more of an issue with drop-throttle stalling. So I added in some 'help', to prevent that.
Earlier software, we bumped the idle speed up, so that it had more hp/tq to catch and prevent drop-throttle stalling. But many users wanted a more normal idle speed. Fine, so in this case we need to be a bit more aggressive in slowing the engine decel rate before it gets to idle.
It really shouldn't be very noticeable when driving. And, in-fact, nearly every new car does something similar. If it is a big deal, I can reduce the affect, and perhaps I will regardless for the update.