megasquirt ignition map?

[BoostedBlood]

so i was doing some tuning last weekend and im not making the power i should. im thinking my problem lays in ignition. i had 2 questions if any one could awnser. first is, if anyone had a stock 4agze base ign. map? (dosent have to be megasuirt, anything woud help) the map im runing at this time doesent look right and making changes to it doesent seem to improve hp, kinda thinking it may be distributor related, which leads to my next question. does anyone know what makes the na and s/c distributors different? i had parts look up the 2 distributors other day and only thing they could tell me what makes them different is "the part #s". im runing a NA distributor and dont have a s/c to to compare >< any input would be great thanks ^.^

[Jackstand Queen]

I can't explain the technical aspects of the Dizzie differences, but I can tell you what to look for.

The earlier dizzies in the 4age had 4 bumps on the shaft (inside the dizzie) beneath the rotor. From 88 onwards, instead of 4 bumps, there was a star looking arrange of of about 15 or so points off the shaft, beneath the rotor. The ignitors for 88 and later were also wired differently.

The fact that your megasquirt runs at all is quite an accomplishment. Congrats on your achievement!

Someone with expertise in megasquirt issues will post some helpful information very soon. I hope.

[BoostedBlood]

thanks ^^ im actually runing a FAST stand alone ecu not megasquirt but noticed a few people were runing megasquirt and was hopeing a screen shot of their ignition map may help me to figure out how far off im on my map. it doesent look right at all and making changes to it dont seem to help, which makes me wana believe my problem may be my distributor. so becides the changes to the pickup, wiring and ignitor between years, there is no difference between a SC distributor and a NA one?

[Jackstand Queen]

If your fast programming interface allows you to meddle with spark advance rate, try advancing it 1/2 a degree, even less if its degree's per second and test drive afterwards. If the Fast has a datalogging function, you might also watch for inputs from the knock sensor in the data.

[toyotaspeed90]

Originally Posted by Jackstand Queen

If your fast programming interface allows you to meddle with spark advance rate, try advancing it 1/2 a degree, even less if its degree's per second and test drive afterwards. If the Fast has a datalogging function, you might also watch for inputs from the knock sensor in the data.

stand alones are interesting.... it's generally not that simple.

if his system is like megasquirt, the map basically looks like a small excel spreadsheet... with a map (kpa) value on one axis and rpm on the other -- so based on engine load and rpm there is a given advance number.


My megasquirted gze runs rich and I have timing backed off quite a bit (I'm using a waste spark/edis system with the stock FWD gze coilpacks)... maybe advanced only 20* max for any given value..... since it's boosted I didn't want to play with it until I had either a WB or put it on the dyno...

that being said, mine is very quick.... faster than a pully'd stock SC and when it had the E series in it, caught up to and passed a stock 2nd gen turbo at high speeds (C series in it now won't allow those high speeds).

Also, my gze is on an older ms1 v2.2 (as in put together like 6 years ago or so) which only has 8x8 maps.... I could post my 7age map, which is probably closer to where it should be, but since it's n/a I'm a little more courageous (and I have a WB on it) to play with the timing.

I'll try to remember, the car computer is in the garage and I rarely power it up.... maybe Sunday (if I have time).... have wedding photos to edit today and an auto-x tomorrow...

[mhamrick]

The problems between the dizzies is that they send a different coded signal to the MS. You have to set the MS to accept and interpretate the signal that is coming from the dizzy.

I do not know if you simply swap another persons tune in if that will fix it but I have a good tune from a friend that I can send you. He had it dyno tuned and started at less the 140 hp and when he finished he was looking at 197 hp. If the your MS and my MS shares the same code then you should be good to go. Good luck!

[te51levin]

Have you verified that your programmed timing matches what you see with a timing light? If they don't agree, it'll never be right.

Can you post a shot of your spark timing table?

[BoostedBlood]

ok checked the timing at idle using a light and it seems ok. the motor has good power from idle to about 4k rpm. im starting to think that the timing advance isent working properly at high rpms but is fine at low rpms perhaps incorrect signal from distributor, which i think was phased at some time but i forget exactly what was done due to the many years and beers that have passed since i last tinkered with it. second i know my spark table is off and thought maybe looking at someones may help me to figure out where mine may need changes, being that i havent really done ignition maping before.

the numbers dont look right to me on my spark tables cause from what i remember the 4ag runs about 10 btdc at idle (with T and E1 connected in the diag plug) and 16 w/o. my dashbord on the fast software (which i belive to be off) tells me im at 28. the spark table im runing now was made by a tuner shop to just get the motor runing so i could begin tuning. when i start making changes to the table to fine tune it doesent seem like it is making any effect on the advance. im kinda unsure how im to check the timing at high rpms and under a load w/o use of a dyno, cause im not gonna be able to get it on one for a few weeks ><. the fast ecu does not have a knock sensor but does offer logging and a wideband. from what i have been told (un able to verify) you can use a wideband to help in assistance to tune your ignition by doing WOT runs useing this method here Ignition Tuning 201, by Jeff Schlemmer of Advanced Distibutors LLC
after a WOT log and compairing my pre changes log to my after changes log there seems to be no change in lamba, also no noticeable difference in power at high rpm.

here is a screen shot of my map, i know its not right but maybe someone can make more sense of it than me, ignition maping being something i havent done much of >< at 158kpa (about 8.5 PSI) you will see that the timing is 34 which seems like too far advanced to me but perhaps im confused of the value in which the numbers represent? i would think it shoud be around 22 at 158kpa but when i retard it down to 22 it seems to be worse so there is definitely something wrong. perhaps someone can point me in the right direction

[BoostedBlood]

oops you gonna want this lol
FAST Spark Table picture by XxOdjoxX - Photobucket

[d962r]

if I can figure out how to get a pic of my spark table I will send it... i am using MS1S&S v2.2 mine seems to run good... 12.2 @ 111mph
If you download megatune I can snd you my compleat tune and you can view it that way so you can see what everything is.

[BoostedBlood]

thanks that would work for me i think i even already have megatune software on my laptop. you could try pressing print screen while looking at your spark table and then paste it in paint or photoshop thats how i been geting screen shots. ^^

[d962r]

I'll try...
Nope.. will not work

[BoostedBlood]

i had some time to work on my car over the weekend and this is where im at... my assumption was correct on falure to advance timing correctly. after degreeing my crank and with help from d962r's megasquirt map (Thanks a ton ) i came to this conclusion. it seems that my fast timing map is off by 20*. so at idle im at 10*BTDC but input in my map is 30. so i wrote a basic map and added the value of 20 to all the cells which seemed to be an easy fix and dramatically increased my power output (unable to tell how much, local dyno still down ><and fuel mileage seemed to go up too . which leads to my next question... does 27* at 8.5PSI seem too much? it seems a little high but im runing 93 octane and have yet to hear any ping. i havent gone any further than 27* and i have reason to believe i may be able to go further because i still think im lacking power compaired to what it should be. maybe its just me expecting more? i dont really like this idea but im thinking about advanceing till i get ping and backing it off 2-3* to get me close to where i need to be. im still not geting any lambda change when i advance timing and i dont know any other way ><; would like to hear what you guys think any input would be great ^^