MPI tuning

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Bigg Tim said:
Yeah, you probably don't need the xtra injectors at that level. Beau said you were going to run at least 12, so you would need them for that. The throttle switch point is okay to use, but I tried all the settings and found the amp to be the best. There were times that I did not want to go full rich at WOT because there was not enough boost to worry about it. Go ahead and trim as much fuel as you need to get er running right man!!!

I know that 1-2 pounds before the TM comes on isn't bad, but sometimes it seems to build more than that when i just had the amp switch. The turbo spools sooo quickly that when the boost builds like that and i still see A/f in the 13's i freak out. I know what you mean about having it come on when i don't want it though. I was going up a hill to my house in 5th and i didn't even realize i was at full throttle and it came on and bogged down because i wasn't under very much boost.
 
Jeph said:
/members/Jeph/MPI_TUNER006.raw

Theres my datalog from last night. The car wasn't warmed up, but i left off the gas in second and third a bit because my wideband was climbing towards 13's (boom06)

You have your switch pretty low, what made you do it like that? I'm not saying it's wrong, just curious. The reason is, you have a lot of neg numbers and you are triming fuel via the 1x16 pretty early. That looks like it's on too early, but if it is working good for you, then leave it alone.

You need more fuel via the xtra injectors up there. So how does it feel? What AFR are you running most of the time while in boost? Tune it rich up top and work on pulling it out, versus tuning lean and working on adding fuel. It's better to take out fuel instead of adding, that way you don't risk running lean.
 
I made some amazing discoveries last night. 1st I replaced my exhaust mani o2 sensor and then Took one of my MAF's and cleaned the sensor in it with some rubbing alcohol and put that in the car and started it up and BAM the car runs like a champ and idles a million times better. So what does all this mean well it means that my car basicly was untuneable before because what ever we would tell the ecu to do the MAF and the o2 were fighting us and not letting us tune the car. I cant tell you how happy I was when I did all this and it worked. I still want to replace the 2nd o2 after the cat just to be safe even though I know its just there to tell the ECU weather or not there is a cat there. Basicly my car has been running so pigg rich for the longest time that I think I fouled out anything the exhaust gas came into contact with. I look forward to finally getting my MPI tuned and getting the car running good.

(dance) (headbang) (eekdance) (mj) (wow) (rockon) (breakn) (yippy) (cabpatch) (msptitani
 
Bigg Tim said:
You have your switch pretty low, what made you do it like that? I'm not saying it's wrong, just curious. The reason is, you have a lot of neg numbers and you are triming fuel via the 1x16 pretty early. That looks like it's on too early, but if it is working good for you, then leave it alone.

You need more fuel via the xtra injectors up there. So how does it feel? What AFR are you running most of the time while in boost? Tune it rich up top and work on pulling it out, versus tuning lean and working on adding fuel. It's better to take out fuel instead of adding, that way you don't risk running lean.

I have the switch that early cause i build boost so quickly, that when its higher, it ends up building almost 3-5 psi before it dumps fuel.
Up top i start to lean out a bit between 12.2-12.8 so I do need to add fuel up there. I am still really rich everywhere else under boost though. And I get some bucking when i shift, so i think i need to trim more fuel, or maybe turning the switch higher would help that.
On a side note, i raced a pretty worked 3rd gen V6 eclipse yesterday, and all i did through first was spin my tires so he pulled on me til i shifted into second and then from there to 80 mph on the onramp i just pulled and pulled and pulled :D
 
Jeph said:
I have the switch that early cause i build boost so quickly, that when its higher, it ends up building almost 3-5 psi before it dumps fuel.
Up top i start to lean out a bit between 12.2-12.8 so I do need to add fuel up there. I am still really rich everywhere else under boost though. And I get some bucking when i shift, so i think i need to trim more fuel, or maybe turning the switch higher would help that.
On a side note, i raced a pretty worked 3rd gen V6 eclipse yesterday, and all i did through first was spin my tires so he pulled on me til i shifted into second and then from there to 80 mph on the onramp i just pulled and pulled and pulled :D

right on, I'm glad you're getting the hang of it. THe bucking between gears can be tuned out, you just need to keep trimming.(thumb) So what are the plans with it, how much boost? There are other things you can do to make it easier, but it depends on how much boost you plan on running. You have an xtra injector, so you can disconnect the coolant clamp and use more xtra injector to compendate. Then you will not have the bucking when the switch comes on, but you may be limited to how high you want to take the boost since you only have 1 injector.

Titanium---that's excellent news man, I'm glad you fingered it out. Did you do an ECU reset when you fixed everything? If not, you may want to befor eyou start tuning again, so you can start from scratch. Now you get to feel what your car should feel like!(thumb)
 
Bigg Tim said:
right on, I'm glad you're getting the hang of it. THe bucking between gears can be tuned out, you just need to keep trimming.(thumb) So what are the plans with it, how much boost? There are other things you can do to make it easier, but it depends on how much boost you plan on running. You have an xtra injector, so you can disconnect the coolant clamp and use more xtra injector to compendate. Then you will not have the bucking when the switch comes on, but you may be limited to how high you want to take the boost since you only have 1 injector.

Titanium---that's excellent news man, I'm glad you fingered it out. Did you do an ECU reset when you fixed everything? If not, you may want to befor eyou start tuning again, so you can start from scratch. Now you get to feel what your car should feel like!(thumb)

RIght now i'm content with the boost i'm running actually. Just because winter is coming, and i don't want too many traction issues in the winter ;)
In the spring I plan to run 12-15 daily.
To stop the bucking i trim at the rpm i am in right after i shift correct? because thats where the switch is coming on and dumping fuel?
How do i disconnect the coolant line switch? The bucking isn't bad at all normally, only when i really push it does it buck, but daily if i'm just driving normal and not going past 5500 then i don't experience it at all.
 
Jeph said:
RIght now i'm content with the boost i'm running actually. Just because winter is coming, and i don't want too many traction issues in the winter ;)
In the spring I plan to run 12-15 daily.
To stop the bucking i trim at the rpm i am in right after i shift correct? because thats where the switch is coming on and dumping fuel?
How do i disconnect the coolant line switch? The bucking isn't bad at all normally, only when i really push it does it buck, but daily if i'm just driving normal and not going past 5500 then i don't experience it at all.

I would trim the 1x16 more and add in the 8x16 if the trimming affected it. To disconnect the coolant, you would need to disconnect the purple wires and put them back to stock.
 
The 1x16 is the column to the right of the 8x16 map correct? I am really unfamiliar with that. I have been doing all my tuning on the 8x16
 
Jeph said:
The 1x16 is the column to the right of the 8x16 map correct? I am really unfamiliar with that. I have been doing all my tuning on the 8x16

Yes, use that 1x16 column on the Analog tab to trim fuel. It is like percentages, so where you have a .80 towards the top, well if you're red cursor box is on that .80 then everything where ever the red cursor on the 8x16 is will only be an 80% value. So if in the 8x16 area you have a 5 and on te 1x16 area you have a .80 (or .70, .60.......) then that 5 will not be the full value, it will be a little less then the five, 80% of it. That allows you to have the full 5 when you are not at the .80 and get less then five when you hit the .80. Make sense? I know it's hard to understand and even harder to explain in text. Hopefully the tuning instructions will help when they are done. If you need more info on that, give me a call.
 
Ahh that makes perfect sense. So instead of taking so much time going through every box in a given rpm range i can lower the percent in the 1x16 map and it lowers the entire range...
 
Jeph said:
Ahh that makes perfect sense. So instead of taking so much time going through every box in a given rpm range i can lower the percent in the 1x16 map and it lowers the entire range...

Lowers the range while in THAT box, or for that load. It's used to trim fuel that the TM adds in the beginning. That's where you get the buck, even when you are shifting, the initial onset of the TM.
 
So does that go for the negative numbers too? If i have a -5, and a .30 in the 1x16, is it only actually pulling 30 percent of the -5?
 
you need nothing other than the MPI , it comes with everything you need to properly tune your car...
 
Jeph---yes that's correct

Wicked--Basically off the MAF. It uses it to sense the air coming in the motor. The more load on the motor, the more air being sucked in. It also uses the TPS to know how much throttle there is and combines everything to get the load. The SW interperates it somehow, that's why the 1x16 column is there, that's the load on all tabs.

The TM has a built in O2 clamp and a coolant clamp to help dump fuel. If you have xtra injectors, you can do O2 tuning, but the standard method is much better IMO.
 
OK did a lot of tuning this weekend and here's my latest datalog.
Its really pretty good at WOT, never goes above a 12.1:1 on my wideband, but there area couple spots where its still richer than 11:1 so i'l tune those out later this week.
not WOT its just a matter of changing a few numbers here and there to get it where it needs to be. Overall it pulls a lot harder at WOT than before.
The road i do my datalogs on is just outside my gf's house, and theres an overpass a ways down, and before i was only getting to about 75 ish by the time the overpass came, but now i'm hitting almost 90 in the same zone... its crazy how much power you can gain by tuning :)
/members/Jeph/Oct23.raw
 
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