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chevpower
August 23rd, 2006, 04:32 AM
I am still new at the tunning thing so please help me if you can, I am tring to tune my car for a bigger cam, I have logged alot in with auto VE and while in SD mode i have the AFR VERY close almost dead on, I copied the VEtables over to the original tune the afr goes very rich with the maf hooked up idles under 12.1 and stays very rich through out the rpm range, Car idles for a sec then dies it will not idle in gear, But in OPSD the car runs great I know i'm missing somthing here but i am lost any help would be greatly appreciated.

SSpdDmon
August 23rd, 2006, 06:26 AM
When you reconnect the MAF, it needs to be recalibrated just like the VE when using this tuning method. You need to create a table in the scanner that looks like the MAF table in the tuning software. ONE column (vertical) along with 85 rows (horizontal) for each MAF Hz. To set it up, use RPM's for the 1 column with Col labels being ",8000" (yes - type the comma). The rows are MAF Hz starting at 1500 and going to 12000 in steps of 125.

You need two tables like this. One with the data parameter being commanded AFR and the other with the data parameter being WBO2 AFR. Then just like the VE, you use the % error to adjust your MAF. Logged AFR divided by Commaned AFR equals % error. Granted you won't hit all 85 cells...but you can make changes above and beyond the cells you do hit based on their change from the stock table. You can see this change by using the compare feature (current tune vs. stock tune).

chevpower
August 23rd, 2006, 06:34 AM
Thanks alot I understand i will get on it now

dfe1
August 23rd, 2006, 06:40 AM
If it were me, I'd run it in closed loop speed density and call it a day. Why struggle with the MAF when you have a good tune in SD?

chevpower
August 23rd, 2006, 07:10 AM
If it were me, I'd run it in closed loop speed density and call it a day. Why struggle with the MAF when you have a good tune in SD?
I want to learn about tunning but for what it is worth my fast car is OLSD with wet n20 I wouldnt have it anyother way but this car is has a dry kit on it and we want to keep it that way for now so we need the maf

dfe1
August 23rd, 2006, 07:18 AM
The VE maps with and without the MAF active will be very different. Your best bet is to either start with a stock VE map and work from there, or start with a VE map from a car with a similar cam that is running with the MAF. I switched from MAF to SD just to experiment, and with no other changes, I had to really work over the VE table. By the way, it is possible to run a custom OS with the MAF which makes llife easier if you're switching back and forth between MAF and SD.

chevpower
August 23rd, 2006, 01:06 PM
When you reconnect the MAF, it needs to be recalibrated just like the VE when using this tuning method. You need to create a table in the scanner that looks like the MAF table in the tuning software. ONE column (vertical) along with 85 rows (horizontal) for each MAF Hz. To set it up, use RPM's for the 1 column with Col labels being ",8000" (yes - type the comma). The rows are MAF Hz starting at 1500 and going to 12000 in steps of 125.

You need two tables like this. One with the data parameter being commanded AFR and the other with the data parameter being WBO2 AFR. Then just like the VE, you use the % error to adjust your MAF. Logged AFR divided by Commaned AFR equals % error. Granted you won't hit all 85 cells...but you can make changes above and beyond the cells you do hit based on their change from the stock table. You can see this change by using the compare feature (current tune vs. stock tune).
I did as you said and all is great but i have one question when i was setting up the map in the scanner it only lets me set up 64 rows thats to i think 9375hz it doesnt show me anything past that is there a reason for this?

Also i am having a little idle problem, Half the time it will die right after start up only on the first attept to start and when backing up sometimes it dies when you stop but only in reverse

SSpdDmon
August 23rd, 2006, 01:57 PM
Make sure you're using the latest version of the software. I'm using v7.3.2 Build 416 and it lets me use all 85 rows. The other option is to do it half and half with the same log (ie 1500~6000 and 6125~12000).

The idle issues might be solved with a slight increase in desired idle rpms.