If you had a choice to launch in one of these three modes, which would you choose and why? (and I do understand that AWD isn't a selectable mode)

Auto 4wd

4HI

AWD (i.e. SS)

 

You mean AWD like a good setup? My Subaru's, or the SS, or like a Porsche 911 Turbo?

If so, then hell ya...I'd prefer a badass AWD system that splits torque not only between axles but between wheels. That's the best way. Also per ger the torque splits from a 50/50 to a more rear-ward bias like a 70/30 as you get going faster.

Auto 4WD does weird stuff on my truck. I had that switched on in the rain once and got on it on some asphault and the assed started hopping around like a buckin' bronco! It was weird. So if you just cruise about with that on, that's all it's good for.

4WD is gonna be the best way to launch the truck with that Radix on top. I can't imagine how it'd hop around in Auto 4WD with a Radix...

 

Since They have not come with a adjustable transfer (like subrau) yet I would go with 4hi. I use it all the time. Just stage, brake pedal to the floor, gas pedal to the floor, let motor sit against tc, release brake on last yellow. Was cutting a 2.1 60' times on mosty stock 8.1,ally combo. I will never go back to 2wd unless I get rcsb 2-wheeler for dragging.

 

got it, 4HI to launch.

8100hammer, so if I put the gas pedal to the floor it will sit right at the stall speed?

 

Stall speed is dependant on MANY things...input torque, weight of vehicle, compression, etc.

But for your truck I'd expect it to flash to 1800-2200rpm with stock stall.

 

thanks hitman, thats why I said stall speed instead of a number.

now I'm curious to see where mine sits at. I've had it at 1800 before but that was only part throttle and in 2wd. Might be different when the pedal is all the way down and in 4wd?

 

Nah, stock converters are TIGHT...About as bad as tight as that Nun that took a vow of celibacy.

Stock motor and converter, I'd assume about 1800-1900rpms is the best you're gonna get.

That Radix is going to add a shitload of power right off idle, that's going to make the converter flash stall...how much...I dunno. Prolly a bit as your truck is so heavy and the massive input torque gains.

 

whats the diff. between stall and flash stall?

 

Here's my type up about stall....



Converters are the "black holes" and "voodoo" of cars and trucks. They are strange, complicated, and misunderstood.

First, stall is based on input torque mainly and also based off vehicle weight. I.e. an anemic, low compression 350 may be able to stall a converter to about 2000 rpm. A hot, higher compression with good heads 350 may be able to get that stall up to 2600 rpm due to making more torque. That is with the same converter. It really depends on your application.

Stall also is in different forms. There is flash stall, brake stall, and actual stall.

Flash stall is, with no traction problems, the peak RPM or the quick jump of the engine RPM's on with the converter. This isn't the best way to measure stall. Insane amounts of torque can make a 3000rpm stall to 4500rpm+
Brake stall is, holding down your brake and gassing the ride with the other foot. That doesn't work too well either b/c you will generally begin to light up the rear tires.
Actual stall is if you had a transbrake on your trans (holds R+D together) so you don't move and your RPM's rise to your stall speed. If you have a 3000rpm stall, that is what your engine should rev to with the transbrake on. You would launch off of that.

Softness depends on the stall and size you go with. High stall, small converters are "loose" converters if you will. Larger diameter usually help keep the looseness away and keep the factory towing up. These act more stock with higher stall. The softness is more likely to be with the part-throttle shift than the WOT ones.

Looseness is hard to explain. Like you'd have to give the vehicle a bit more gas to get moving and depending on diameter. Generally your part throttle putting around rpms are about 2000-2400rpm again depending on converter and vehicle.

Also stall converters help with shift extension on the upshifts...meaning you will have a higher RPM in the next gear you shift into. This is very nice for wide ratio boxes like the 4L60E. In addition to that, low throttle/cruising is also improved in that weird area where you are going too fast for a 2-1 downshift and too slow for 3rd...your RPMs will be a bit higher so it will not feel as much like a dead spot. That happens due to the big jump in ratios between 1st and 2nd gears.

Finally, with a high stall converter, install a large transmission cooler. Even if the instructions say it is okay to use the factory cooler/heat exchanger get one. They are cheap insurance. $50 cooler or $2000+ transmission?

 

4hi launch here, auto is no good once you start making some power.

can't really coment on AWD but i think that would be the best other than you wouldn't get to show off doing big smoky burnouts by selecting 2wd.