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So for the past year I've been trying to learn how to self tune, I haven't really messed with my spark map, it is a map that was scaled for boost off of a 94-95 mspnp base map. I've been running a pretty similar version of the map for around a year now. My first motor had low compression, I pulled that and removed the head to find no signs of det, this new motor that is in seems to be alright as well. I've been running an extremely slow spooling 8 psi setup, I reach full boost in second gear. I made a pair of electronic det cans over the last week and installed them yesterday, the car seems pretty content with the map running on 93 but there are a few areas that have me worried. My base timing is set to 10 degrees, I have been doing this with the trigger angle offset, I believe this is the wrong way, yes? I idle on the spark map at around 19-20 which from what I've read is extremely high. Also I run as much as 37-38 degrees between 3000-4000 rpm under 100 kpa, is this right as well? I came across one thread which said this is unbelievably high, also the 10 degree retard when going into boost sometimes makes the car feel sluggish, it also feels like after 5k rpm the car looses breath. My thoughts are to retard my angle offset by around 10 degrees and shift the entire map down around 10 degrees as well. Does this make sense? I believe this will give me a similar range of values that have high 20's and mid teens on and off boost in the mid range, also this will shift my idle timing down to a true 10 degrees. Is my thought process correct? I hear no knock so I believe this map is "safe" but it could be heavily refined.
Way too much timing between 75 and 100 kpa. 100 kpa should be around 28-30. Use interpolate. Big jumps are bad. Also, look around for other maps, not really sure how you came up with that.
What are you talking about shifting the map?? You want to adjust the trigger offset and then change the whole map by 10 degrees? Set the trigger offset with a timing light such that your timing is accurate, then make a decent timing map. If you start changing the trigger offset, then these numbers mean nothing.
Way too much timing between 75 and 100 kpa. 100 kpa should be around 28-30. Use interpolate. Big jumps are bad. Also, look around for other maps, not really sure how you came up with that.
What are you talking about shifting the map?? You want to adjust the trigger offset and then change the whole map by 10 degrees? Set the trigger offset with a timing light such that your timing is accurate, then make a decent timing map. If you start changing the trigger offset, then these numbers mean nothing.
I've set the base timing using trigger offset, but my question is would the shift between 75-100, would knocking that down to 28-30 make the car feel gutless? I looked around at a few maps and understood that the midrange should be around 30 degress, I just didn't know if the difference in values between that and idle made a difference. My thought process behind shifting the map, which is probably wrong, was that retarding the trigger offset and retarding the map would bring my values down to roughly what all the other maps I have seen look like.
I also read that idling in the 20's was not good, that was another reason I though to change trigger offset
Knocking that region down to 28-30 won't make the car feel gutless, it'll keep you from knocking and blowing your engine. You're probably way past MBT.
If idling in the 20's is bad, why is your timing in the 20's at idle???
Everyone else who has a standalone ECU has set their trigger offset to where 10 degrees on the standalone equals 10 degrees at the crank. If you've done that correctly, that means when your timing map says 20, the coil is firing 20 degrees before top dead center. Everyone else's timing map says ~10 in the idle region, this means that their coil fires 10 degrees before top dead center. If you offset your trigger offset by 10, and then change your idle region by 10, you are still going to fire your coil 20 degrees BTDC (or 0 since you mentioned retarding the trigger offset by 10). If you change your trigger offset, then your spark map no longer correlates to anyone else's and your numbers mean nothing.
I don't understand why if you have figured out that your idle and mid range spark map is bad, why haven't you changed it to match others, and why are you wanting to try something completely different?
Are you 100% that if you change you timing from "used table" to "fixed" and you set it to 10 degrees, that your timing light shows 10 degrees?
I just looked at the map today for the first time because I figured it was the next logical step in the tuning process. So I changed the 75-100 to around 28-30 and then the idle area to 10. Now obviously when I start the car it will not be at 10 degrees base timing, which setting do I change to get to 10 degrees?
so if I took my idle corner down by 10 and then raised my trigger offset by 10, so that 10 degrees on the spark map equals 10 degrees on the crank, would this make sense?
Your timing map as you posted it indicates that you need to have someone scare you very badly about the dangers of screwing with the timing map without a dyno or prior experience. Does someone need to do that, or will you take my word for it and take the car to a dyno/professional to have the spark map fully tuned?
Your timing map as you posted it indicates that you need to have someone scare you very badly about the dangers of screwing with the timing map without a dyno or prior experience. Does someone need to do that, or will you take my word for it and take the car to a dyno/professional to have the spark map fully tuned?
I get it now that it was extremely advanced, that's why I came here to have you lot critique it. I want to learn to tune this car by myself because it genuinely interests me, many others have learned to self tune on here so why can I. Like I said before I didn't even really begin to look at the spark map until today which was probably a big mistake on my part due to the advanced on it.
This is the new map trimmed down around 10 degrees in the mid range. I could probably bring the mid range up around a few more degrees, the motor sounded good on the det cans so I assume nothing is harmed, the proof will probably be in a compression test though. The reason for the big retard is the mid range was that I heard knock is harder to get rid of than to find it, so hopefully I can creep it back up a few more degrees. I looked at a few of my friends timing maps and they seemed to have a lot smoother of a timing map that looks more like my second one rather than my first. I now realize how dangerous the first map was and I would like to thank you guys for letting me know that, I had my suspicions about it being too advanced and you guys helped me change that. The idle timing seems to be in the teens like a lot of other maps, any thing that I should change in that area? I'll see what I can dig up as far as utilizing virtual dyno, VEAL, and my det cans to find the next step in the spark mapping process. Thanks!
Last edited by Forrest95M; 12-15-2016 at 07:38 AM.
when I start the car and hookup a timing light to get 10 BTDC at idle
Originally Posted by Forrest95M
so if I took my idle corner down by 10 and then raised my trigger offset by 10, so that 10 degrees on the spark map equals 10 degrees on the crank, would this make sense?
you're making it way too complicated.
set fixed timing to 10* btdc, start car and use a timing light to verify you are getting 10* btdc. if not, adjust trigger offset until you do. then turn off fixed timing and run off the spark table.
if you're spark table is calling for 16, and you're only getting 10 at idle you're doing it wrong.
set fixed timing to 10* btdc, start car and use a timing light to verify you are getting 10* btdc. if not, adjust trigger offset until you do. then turn off fixed timing and run off the spark table.
if you're spark table is calling for 16, and you're only getting 10 at idle you're doing it wrong.
thanks, that's what I was looking for. I was confused because on some maps the idle is around 15-16, why would they be like that though if it was so easy to change?
some folks like to run 10 at idle, some higher. you can tune idle, afr, and timing to get the most vacuum at idle...or just set it and forget it.
i had mine at 10, took it in for a tune and he put it at 13. if you're not using idle advance then you could bump the 500 rpm cells up a few degress higher than idle to help catch it if it stumbles
I have my idle spark cells set at 17 on all my cars. Scott Clark from DIY told me it does not really matter as long as the car idles fine. Having it a bit higher also makes the range available for timing adjustment at idle a bit more. I don't think that will matter on the MS1 you run though.
You are doing it wrong. He meant set timing to 10 fixed in the drop down menu and verify with the light. Then you can switch it off and return to running off the table. Return the table values to around 17 for the timing table.
12-14-2016, 10:07 PM
Timing map help
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