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Old 05-09-2005, 02:51 PM
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I was reading one of the tuning docs posted in the sticky section. It mentioned that you can start tuning your VE table by running without the MAF and are able to do this over the course of a week or so. Can I start tuning my car and drive it around with the MAF disconnected to get the LTFT dialed in?
Old 05-09-2005, 03:11 PM
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^^^ yup that's what you want to do... use the LTFT histogram to adjust your VE table with the MAF unplugged... then once you hae the VE dialed in you can either stay Speed Density or you can put the MAF back on and then scale the MAF tables to get the LTFTs back to around 0
Old 05-09-2005, 04:44 PM
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If I'm trying to get the VE Table dialed in and am driving around for a week or so and the weather is changing, colder in the AM and hot in the afternoon, is that going to have a big effect on my tuning? Will my car run ok with the MAF unplugged for a week while tuning? Thanks, really excited to start tuning but want to get a better understanding of it.
Old 05-09-2005, 05:31 PM
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you should have no problems...
did mine through a week...
I just logged on teh way to work...flashed...loged on the way home...flashed...only took me about 3 days to get it all perfect...then I went back and did a saturday drive, and used it as a reference...same day right after that drive plugged back in my MAF...and scaled it accordingly...did a 3rd drive and tewaked it jusat a little...did a 4th drie to check my math
I'm still debating going MAFless altogether....but its scaled for if i decide not to
Old 05-09-2005, 05:32 PM
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Originally Posted by NVE THIS
If I'm trying to get the VE Table dialed in and am driving around for a week or so and the weather is changing, colder in the AM and hot in the afternoon, is that going to have a big effect on my tuning? Will my car run ok with the MAF unplugged for a week while tuning? Thanks, really excited to start tuning but want to get a better understanding of it.
I did mine over the course of a month with constantly changing weather and it wasn't an issue for me. Take your time, start logging and make adjustments. Don't be hasty to make changes once you flash and reset fuel trims. Give the fuel trims time to settle down to a learned state and make adjustments based on good data.

Good luck!
Old 05-09-2005, 05:39 PM
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Now here's another wrench to throw in the equation. I am installing a cam (FMS-F14) in a week or two. It will be in by the end of May. Shoud I wait to change things until after the cam is in? Right now my LTFT's are about 9-15 I konw that's bad. What would be the best way to approach this?
Old 05-09-2005, 05:53 PM
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you can start playing with it now and start from scratch when the cam is in...its better to get into it now so you almost know what your doing once you do the cam.
Old 05-09-2005, 05:56 PM
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Originally Posted by 405HP_Z06
I did mine over the course of a month with constantly changing weather and it wasn't an issue for me. Take your time, start logging and make adjustments. Don't be hasty to make changes once you flash and reset fuel trims. Give the fuel trims time to settle down to a learned state and make adjustments based on good data.

Good luck!

if you do the STFT method you dont have to do it slowly...you can just do one right after teh other..and you dont need to wait a long time to log...you do still want to reset fuel trims inbetween logs.... and you do want to keep an eye on the LTFT for any oddities...
Old 05-09-2005, 07:44 PM
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Originally Posted by soundengineer
if you do the STFT method you dont have to do it slowly...you can just do one right after teh other..and you dont need to wait a long time to log...you do still want to reset fuel trims inbetween logs.... and you do want to keep an eye on the LTFT for any oddities...
Can you explain or point me to the STFT method. I might have read it but I've done so much reading I can't remember where it all is. Thanks.
Old 05-10-2005, 01:13 AM
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Disable LTFT... unplug MAF or set fail to 0...then basically go out and log stft....and hit all the rpm's...you need a nice long abandoned straight stretch of road to make it easier...but you can do it just about anywhere...
basically pulse your gas pedal and watch the histogram...hit every cell 4 or 5 times...go up to the next RPM...lather rinse repeat....
when done do a copy and paste special add.....
and do the whole thing over again... the 2nd time you do a paste special multiply by %
teh 3rd time do multiply by %-half....if you even need to do a 3rd time...
you dont even have to log a long time and you dont need lots of miles between logs...
I did all mine in about 2 hours total.....
my LTFT's and STFT's are all within the recommended 0/-4 range, and I have double checked them several times during normal driving to be safe...
you dont need to worry about smoothing ...adn from what I have seen smoothing tends to mess things up a little and make you further away from the goal....
If you have stock heads..you flow #'s will be a little jagged..ported heads and your tables will naturally be a little smoother...
but teh airflow is dependent on so many parts that anything could make it not so smooth...

hell today I logged my drive home from work...about a half hour drive..some highway...some streets.... all my LTFT's were 0 and -1...all my stft's were 1,0,-1,-2

proof positive that the method works...




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