Speed density tune...can someone explain
What I think happens is when you start to tune a car with a certain amount of power, the MAF cant read it past 1 bar accurate, so fuel/air combo will be a little fucked up and not as accurate making it harder to tune.
With an SD tune I think you have certain "tables" that you rely on to use instead of a device that measures air.
Im not too familiar with it, just some random things Ive heard from.
With an SD tune I think you have certain "tables" that you rely on to use instead of a device that measures air.
Im not too familiar with it, just some random things Ive heard from.
Speed Density, is where you remove the MAF, and just go by the MAP sensor, to guess, or predict the airflow coming into the motor, instead of using a sensor designed to measure airflow.
LS1 edit, HPtuners, EFI Live, Tuner Cat, and others are just different software packages that allow you to tune the vehicle. You can do speed density tuning with any of them that allow access to the VE tables.
The maf doesn't have a problem reading more than 1 bar, it is just measuring airflow. There is a pcm limit of 512 g/sec though.
Ryan
LS1 edit, HPtuners, EFI Live, Tuner Cat, and others are just different software packages that allow you to tune the vehicle. You can do speed density tuning with any of them that allow access to the VE tables.
The maf doesn't have a problem reading more than 1 bar, it is just measuring airflow. There is a pcm limit of 512 g/sec though.
Ryan
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From: Ft. Lauderdale, FL, USA
Originally Posted by slow
Speed Density, is where you remove the MAF, and just go by the MAP sensor, to guess, or predict the airflow coming into the motor, instead of using a sensor designed to measure airflow.
LS1 edit, HPtuners, EFI Live, Tuner Cat, and others are just different software packages that allow you to tune the vehicle. You can do speed density tuning with any of them that allow access to the VE tables.
The maf doesn't have a problem reading more than 1 bar, it is just measuring airflow. There is a pcm limit of 512 g/sec though.
Ryan
LS1 edit, HPtuners, EFI Live, Tuner Cat, and others are just different software packages that allow you to tune the vehicle. You can do speed density tuning with any of them that allow access to the VE tables.
The maf doesn't have a problem reading more than 1 bar, it is just measuring airflow. There is a pcm limit of 512 g/sec though.
Ryan
Originally Posted by VooDooo
I dont know why SD tuning is so rare in the US. The majority of cars tuned in Australia use this method. Some get a Maf tune first but soon upgrade to Mafless.
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Originally Posted by Quickin
What it is?
How is it different than an LS1Edit type tune?
Is it better to do it this way?
.
How is it different than an LS1Edit type tune?
Is it better to do it this way?
.
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Joined: Dec 2001
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From: Ft. Lauderdale, FL, USA
Originally Posted by LASTLS1
If your running a big cam I would do it. I tried to keep my MAF last year and my car didn't do well at idle or slow speeds. I needed a SD tune!!!!
Maybe I need a much bigger cam
Im running SD on my car. right now its just to get used to tuning in SD, but when i put in my cam, it will allow me to tune a bit more accurately, as long as i keep up with it.
FYI, Cyrsler doesn't have a maf on a decent number of their cars(i know the hemis). they run SD, but they also have widebands. that is what makes it work for various climates
FYI, Cyrsler doesn't have a maf on a decent number of their cars(i know the hemis). they run SD, but they also have widebands. that is what makes it work for various climates
Originally Posted by Quickin
I have a 242/242 .610/.610 114 lsa It idles like a stock LS1, zero lope, no shaking at all.
Maybe I need a much bigger cam
Maybe I need a much bigger cam
. Try to tune that one with a MAF! I just pulled that one out to put a real cam in it! 
SD Tune I'm currently tuning using the SD meathod. I had the car running, shut her down and went SD. I started to tune my VE tables.... done a few normal driving runs. I shut her down and she cooled off.... I took off my wideband, and thought I would continue the tuning in the morning. Next day, she started rough, really rough. I shut her down.. figured I'd tune another day.... now she won't start, seems I've fouled all my plugs... she is running so rich. As it stands, I gotta replace my plugs and mybe my 02's...... I wish I knew what I was doing!
Originally Posted by koji777
I'm currently tuning using the SD meathod. I had the car running, shut her down and went SD. I started to tune my VE tables.... done a few normal driving runs. I shut her down and she cooled off.... I took off my wideband, and thought I would continue the tuning in the morning. Next day, she started rough, really rough. I shut her down.. figured I'd tune another day.... now she won't start, seems I've fouled all my plugs... she is running so rich. As it stands, I gotta replace my plugs and mybe my 02's...... I wish I knew what I was doing!
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From: Ft. Lauderdale, FL, USA
Originally Posted by LASTLS1
You do! My cam was a 275-286 .735-.715 @ 112+3 . Try to tune that one with a MAF! I just pulled that one out to put a real cam in it!
. Try to tune that one with a MAF! I just pulled that one out to put a real cam in it! Is that cam in a street car? How does it run on the street?
Originally Posted by Quickin
Damn, I don't want to shake anyones fillings out. My weal link in my 436 are the heads...they're still just LS1 ported heads and a stock ported TB. If i go with a bigger cam I'd be wasting my time I think?
Is that cam in a street car? How does it run on the street?
Is that cam in a street car? How does it run on the street?
