Sniper EFI/4R70W/Atlas

[gregturpen]

In the process of the swap, new engine with Sniper EFI, mated to4R70W and Atlas. What have others done for VSS when performing this or similar swaps? EFI doesn't require speed input, trans controller does, thru the transmission. No problem there. But how does the engine/trans perform when shifted down to 4L with the Atlas. Is there an issue? I've called Holley and MSD, both point me to the other. Thanks in advance.

 

[snipes243]

The atlas uses a Hall effect speed sensor that can input into the Holley software. There is A sensor that can be added to the atlas to tell when it’s in four wheel drive.

 

[Broncobowsher]

You didn't state what the trans controller is. Presuming it is a quick shift?
It pulls output shaft speed and does not need not care about vehicle speed.
The only thing you would need a vehicle speed sensor for is the speedometer.

How will the trans work with the Atlas? Pretty normal. It will go through the gears quick. In low range it won't take much and you will be up in overdrive. This is where a second shift table comes in handy. You can drag the shifts out to a much higher RPM and low throttle for a little better drivability. Might drop a little line pressure at the light throttle as well to try and soften the shift.

Another trick is to set the 1-2 shift point to 0 MPH at light throttle. This will start you in 2nd gear from a stop. Takes out that super annoying 1-2 shift at 3 MPH. But you can manually downshift into 1st when you do need all the gear. Or leave in drive when you want low range, but not the lowest of low range. Was one of the best things I did when programming shifts for the 4R70W.

 

[gregturpen]

@snipes243 ... I'm not really concerned with knowing whether or not I'm in 4L or even speed, rather was just wondering if engine performance will be effected by being in 4L, but the VSS from the trans saying something else, then getting this data back to the engine. I haven't ordered the Atlas yes and I need to decide on mechanical or electronic speedo. I'd really like to use the stock dash speedo
@broncobowsher ... I'm using the MSD Atomic trans controller and harness for the 4R70W. Seemed to be the most straight forward approach.

 

[Broncobowsher]

The Sniper has zero vehicle speed reference. Just the Ford stuff runs a speed sensor back into the engine computer. Don't think any of the aftermarket stuff does. I think you can configure a pin to read it, but it would only be used for data logging. Not controlling the engine.

Never played with the MSD transmission controller. Only the US Shift. And only the older version of that. Never even looked at the manual for the Atomic.

 

[MonsterBIlly]

I am running this exact set up.
I used the us shift controller
There are setting on their software that addresses this. It is very easy to set up. Shifting is fine in 4l.

You will need a longer speedo cable to reach the atlas, but the mechanical speedo off the atlas is fine. That is what I am using.

 

[gregturpen]

@monsterbilly, thanks.
Can you share how you addressed the crossmember?

 

[bigmuddy]

EFI 4r70w

Subscribing and bringing this back to the top.

I am giving serious consideration to swapping in the 4R70w as the 6R80 is just to cost prohibitive also wondering if the 6R80 would really be a benefit with a 400 hp 5.8?

So, bringing this back to the top to see what has transpired with your build, and what you did for the crossmember.