Tweecer tuning

[sinistercoupe]

i got my 75mm bullet blowthrough back from Pmas. I put in the transfer using the 9 to 30 point conversion and it seems to look good. It maxes out at 3250 kg/hr at 5 volts. I also did 50# for High inj slope and 60# for low inj slope and the other usual stuff like putting the wot fuel multiplier at 1,cranking fuel pw vs time at .6

I started the car and to my suprise it didn't stall immediately like it did before with just the stock computer. I just idled it in the garage and it seemed to idle good with the afrs where they should be at 14-15:1

I changed a few of the AFRs in the base OL fuel table to be richer since i'm running 10 psi of boost with a T-76 q-trim turbo and a built 351w. Now my question is if the maf transfer is correct out of the box the AFRs that i have entered in the base OL table should be the same as what my wideband would say doing a full throttle pass down the road?

If it isn't the maf transfer needs to be edited and that is where i need to be able to datalog correct? I need to be able to datalog the maf voltage correct? I was looking into that dataQ that dale was talking about since it will be cheaper and i won't have to have downtime with my car though.

[Italian LX]

Be caustion using the 9 to 30 point converter. When you save it, it usually gives some wierd readings. Open your current tune in CalEdit and look at the MAF transfer and see if it still looks right.

The glitch in the conversion will usually result in the voltages only going up to 1.xxx up until the last point... and it will be at like 5 volts. It will be pretty obvious if this is your problem.

[sinistercoupe]

Be caustion using the 9 to 30 point converter. When you save it, it usually gives some wierd readings. Open your current tune in CalEdit and look at the MAF transfer and see if it still looks right.

The glitch in the conversion will usually result in the voltages only going up to 1.xxx up until the last point... and it will be at like 5 volts. It will be pretty obvious if this is your problem.

I never actually saved the maf transfer. I just put the 9 point curve in,it spit out the 30 point curve and i just wrote the tune to the Tweecer. I remember trying to save a transfer i typed in manually and yeah like you said it gave weird numbers when you tried to retrieve it from the maf transfer folder.

[Disney Lincoln]

Now my question is if the maf transfer is correct out of the box the AFRs that i have entered in the base OL table should be the same as what my wideband would say doing a full throttle pass down the road?



Not exactly. You will have to watch your AFR when making a WOT pull very carefully until you can get it dialed in right. It is near impossible for the out of the box MAF Xfer to match what you load into your OL table on a boosted application. Be very careful the first few times you hit it. I would start out with the WOT high load at 10.5 or so and see what it does from there.

Also, i'd lower the cranking PW to .4 or so.

[Italian LX]

I never actually saved the maf transfer. I just put the 9 point curve in,it spit out the 30 point curve and i just wrote the tune to the Tweecer. I remember trying to save a transfer i typed in manually and yeah like you said it gave weird numbers when you tried to retrieve it from the maf transfer folder.
You might want to make sure the MAF transfer is still correct in your tune. I don't think you have to save the MAF to get the funky readings -- just using the converter can cause it. Just go ahead and read the current program in CalEdit and verify to make sure.

[sinistercoupe]

You might want to make sure the MAF transfer is still correct in your tune. I don't think you have to save the MAF to get the funky readings -- just using the converter can cause it. Just go ahead and read the current program in CalEdit and verify to make sure.

aight cool i'll check it out. I don't remember seeing any weird numbers when i did a tweecer read to recheck everything...so as long as the volts go up from 0-5 volts in small increments it should be good to go right.

[sinistercoupe]

Not exactly. You will have to watch your AFR when making a WOT pull very carefully until you can get it dialed in right. It is near impossible for the out of the box MAF Xfer to match what you load into your OL table on a boosted application. Be very careful the first few times you hit it. I would start out with the WOT high load at 10.5 or so and see what it does from there.

Also, i'd lower the cranking PW to .4 or so.

Ok i have it at 11.0:1 right now. I'm just going to start out with 6 psi at first to see what the AFR is at when the weather gets better. did you ever upgrade yours to an RT?

[Disney Lincoln]

No, still on the base. I had an RT in it for a while to help get the tune a little better, but it didn't help all that much. Just hacking away at it with teh Base model has done the most for it.

I am changing things on the car right now, so I will be back into it soon.

FWIW, I use another program to convert my 9 point to a 30 and enter it in that way.But it sounds like you are on track if it idles well and you have a peak for around 3200 at 5V. (at least if it's a 60# meter)

[sinistercoupe]

No, still on the base. I had an RT in it for a while to help get the tune a little better, but it didn't help all that much. Just hacking away at it with teh Base model has done the most for it.

I am changing things on the car right now, so I will be back into it soon.

FWIW, I use another program to convert my 9 point to a 30 and enter it in that way.But it sounds like you are on track if it idles well and you have a peak for around 3200 at 5V. (at least if it's a 60# meter)

hey its just a 50lb cal but its blowthrough. Does that sound right to you? Should i use another program and see if its different then the caledit 9-30 point setup? Maybe PMAS has changed the way they calibrate the meters? It looks like after 4 volts the airflow goes up a good bit...i assume due to the fact its blowthrough?

[Disney Lincoln]

oh yeah.. Blowthru, that should be right.

Yes, all of them shoot up after 4V. That is normal. If it's working for you now, I wouldnt worry about loading it into a different program.

[sinistercoupe]

oh yeah.. Blowthru, that should be right.

Yes, all of them shoot up after 4V. That is normal. If it's working for you now, I wouldnt worry about loading it into a different program.

Cool,i figured that. Do you use any other logging device like DataQ to datalog or just adjust the maf transfer by feel since you don't have an Rt. I may need your help getting this dialed in since i just have a base tweeer like you.

[Disney Lincoln]

No datalogger, just adjust by what the WB tells me. I'm glad to help where I can. There are much more knowledgable people on this site than I though! This is where I come when I have questions about it.

[sinistercoupe]

No datalogger, just adjust by what the WB tells me. I'm glad to help where I can. There are much more knowledgable people on this site than I though! This is where I come when I have questions about it.

thanks,i took it for a drive today and drivability/idle/part throttle is good. I made a few wot passes just letting it make 6 psi (.4 bar) for a bit but didn't stay in it very long since it was dark and i was scared of cops..lol...the AFR went to about 13:1 or so which is a lot better then before.

That was with the top row of the base OL table at 11.0:1 and the unmodifed maf transfer that i put in for the blowthrough bullet. I changed the top row to 10:1 and loaded into position 2 on the Tweecer and i'll probably tune it some more this weekend in the daytime.

Disney,do you have a logger for your WB? I think i need to get one..i have a plxm300 now and kind of wish i would have got the zeitronix instead since it has datalogging for the same price.