Megasquirt Hey Ken (muythaibxr), I need to ask for a big favor
Thread Starter
Joined: Jun 2003
Posts: 1,324
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From: Western Colorado
Hey Ken (muythaibxr), I need to ask a big favor of you. I've been doing ALOT of searching on negative timing split and I def. want to be able to use it, but unfortunately, the megasquirt current code cannot support this, which makes me sad
Like, really sad.
So my question is this:
Is there anything you can do? At this point, I'll practically PAY someone, in order to be able to run negative split.
The best mpg I've been able to get so far has been 15-16 with my afr's anywhere between 14.2 - 16+
My timing may be a bit too advanced however, because I steadily run 87 octane and I'm using the timing map made by Brian (BDC). I assume his map is for 93 octane because I had to bring my 90 - 100 kpa values down to 20-22, or else I get detonation above 5500 - 6000. I am fairly certain that I need to retard my entire map.
FYI: If anyone wants to know why, well then feel free to check these search results:
https://www.rx7club.com/search.php?searchid=4652796
Like, really sad.
So my question is this:
Is there anything you can do? At this point, I'll practically PAY someone, in order to be able to run negative split.
The best mpg I've been able to get so far has been 15-16 with my afr's anywhere between 14.2 - 16+
My timing may be a bit too advanced however, because I steadily run 87 octane and I'm using the timing map made by Brian (BDC). I assume his map is for 93 octane because I had to bring my 90 - 100 kpa values down to 20-22, or else I get detonation above 5500 - 6000. I am fairly certain that I need to retard my entire map.
FYI: If anyone wants to know why, well then feel free to check these search results:
https://www.rx7club.com/search.php?searchid=4652796
Thread Starter
Joined: Jun 2003
Posts: 1,324
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From: Western Colorado
^ and those mpg #'s are during cruising and light loads, and never exceeding 4k rpms. When I want to drive it more aggressively, I get around 11 - 12 mpg again. It's pretty pathetic.
Thread Starter
Joined: Jun 2003
Posts: 1,324
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From: Western Colorado
what?? That makes noo sense
Why should I run 87 octane in my NON-TURBO block??
Read my sig a little more carefully.
Why should I run 87 octane in my NON-TURBO block??
Read my sig a little more carefully.
Last edited by 2Lucky2tha7; Jan 27, 2008 at 11:11 PM.
Thread Starter
Joined: Jun 2003
Posts: 1,324
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From: Western Colorado
I've been doing alot of searching for an N/A timing map similar to the stock ecu map on all the other ECU sections and so far I've found nothing. I'll keep searching though. Although I have series 4 housings, I'll settle for either s4 or s5 timing numbers, if anyone happens to know of any, or anywhere I can find them., it would really help out. This is my daily driver, so any increase in mpg will help, thus, the reason for this post. I used to get 19 mpg on my last block which was a ported s5 6-port with factory ecu, so I kind of miss those #'s.
MS2/extra supports negative split.
There is no way in the MS1 to support negative split, as there aren't enough timers built into the chip to do that.
The current ms1 code uses the same timer for leading and trailing, and basically gets clever about how to schedule dwell to avoid ignition misses.
Ken
There is no way in the MS1 to support negative split, as there aren't enough timers built into the chip to do that.
The current ms1 code uses the same timer for leading and trailing, and basically gets clever about how to schedule dwell to avoid ignition misses.
Ken
Thread Starter
Joined: Jun 2003
Posts: 1,324
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From: Western Colorado
Awesome! In that case, I'm going to buy the MS2 daughtercard for my MS. So, a quick question. My understanding is that I put the MS2 daughtercard in and load the MS2 firmware, correct? In the meantime, I will be searching.
Thank you
Thank you
Last edited by 2Lucky2tha7; Jan 28, 2008 at 11:22 AM.
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put the ms2 daughtercard in, load the ms2/extra firmware, and do a bit of internal rewiring (if you were using the
second trigger).
The internal rewiring should be done first... You should also wire S12C to JS9 (I believe, you should check the megamanual to confirm) internally. That keeps the stepper motor controller from getting too hot.
Ken
second trigger).
The internal rewiring should be done first... You should also wire S12C to JS9 (I believe, you should check the megamanual to confirm) internally. That keeps the stepper motor controller from getting too hot.
Ken
Thread Starter
Joined: Jun 2003
Posts: 1,324
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From: Western Colorado
I'm using the modified CAS setup, so I fortunately won't have to mess with anything else which is pretty awesome! Thanks for the info Ken! I'm really looking forward to this
damn those are pretty bad #'s. I wonder if it had to do with the 4 port dsign vs. the 6 port one.. is it making good power?
I'm running a 6port 1/3 bridge with s5 n/a rotors and NO trailing spark at all and I get better mpg than that. Maybe your compression is low? I really don't think you should have to run negative split to get above 18mpg. That really sucks man.
I'm running a 6port 1/3 bridge with s5 n/a rotors and NO trailing spark at all and I get better mpg than that. Maybe your compression is low? I really don't think you should have to run negative split to get above 18mpg. That really sucks man.
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