Actually the RX and servo are probably digitally connected but the D/A to the servo motor is where the latency can differ..
I would need to hook up the servo's next to each other and compare response times.

I got confused reading the setup as you listed the rear first lol. I need more info, what diff, how is it setup? What droop do you currently have? I would guess that a lot of roll could be why your loosing the back end. On carpet, you shouldn't have a problem with S grips on the back, unless the car is lifting off the tires. This below helps cement the back end, while making the car turn hard in the corners.

Give this a try -

Diff - 3 racing gear diff, 500k oil

Front -
S grips - Full sauce
Red spring
35wt oil 3 hole piston
-1° camber
.5° toe out
.5mm droop

Rear -
S grip tires - Full Sauce
Yellow or white springs
35wt oil 3 hole piston
Hard roll bar
-2 to -2.5° camber You can go to -3 but start lower and find the sweet spot for the track
1.5° toe in
1mm droop

I run very similar setup to this, until the car starts to lift when I really throw it into a corner. I then ad a very small bead of CA, right at the outside edge of the tread on the front tires only. You may find the car will push now, but it should come back (try more camber if its still pushing) HTH

Cseils
What exactly do you mean by your rear is breaking loose?
Is the car spinning out, is it turning over etc...???

I think in real-car lingo, he means the rear is stepping out when he lets off the throttle before the turn.

I am at full throttle on the straight which leads to a medium right hand high speed turn which leads into the sweeper. The rear end loses traction half way through the turn. I am usually able to correct it before going all of the way around.

Usually steps out on throttle through the turn..

True, but you get the point... since especially difficult to do on a FWD car.

Tamiya still hasn't released a Fall promo-code. Last year I probably bought 3-4 kits from them by now.

Sounds like you need to take away some front traction. I recommend super glue on the outside edge of the front tires.

Try one step harder front springs.

Did it

I'm thinking the droop in the rear might be the issue. I checked the rear and I had a lot more there then I thought. I have 3mm droop in the rear, what do you run?

My droop was: 1 o-ring in the front shocks, no o-rings in the back shocks.

I just got back from a 3 day race, and my setup was similar to axle's. Soft in the front, hard in the back.

I ran 2 different sets of front tires. One set has CA just on the edge of the outter tread. The other had CA on the entire outter tread. By the time the mains were up, there was so much traction that it was necessary for me to run the tires with CA on the entire outter tread.

I'm guessing this is a carpet surface?
Do you sauce your tires, since you already did the ca on your front treads...
If you do, to what extent?

Yes, carpet as stated.

In this case, I sauced the rears about 3/4 - full width. The fronts, the first two inner treads.