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Back when I was JB4, I was able to cut 3.9s RWD.

An AWD car should be able to cut better, probably like a 3.7 on the street. It'll take some practice with footbraking off the line, but it's doable.

Here's the JB4 custom map 6 I had back then - this is full send and only recommended if you know you've got good 93, are watching temps and timing etc, and make if you've got a full turbo back exhasut setup.

RPM 1500-7000, interval 500 +3 +3.5 +4 +5 +8 +8 +7 +7 +7 +5 +3 +0

This is on a RS400, for a SS/Luxe add 5psi to all of those.
 

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I think there's a lot of misconceptions about the boost profile on a RS400.

It's 14psi peak, not flat, and even then the car doesn't always request 14psi. For example, my RS400 I noticed that according to the JB4 logs, it never requested more than 13ish psi.

The highest overall boost request was +8psi resulting in a max boost of 21psi. This is still less than a lot of other tuners run on stock turbos early on in the rev range. I usually tune cars to 18-19 nowadays, but there's some guys who want that extra torque and we'll still push them to 21 on request.

Here's 3 data logs with 3 similar JB4 profiles I tested on a dyno that day, one was from Jay who ran an 11.9 on JB4

 
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