Thanks for the info on what mods had been done. The other info is what Race series.
In beginner there is a 4wd challenge that has SS11 in it, as well as the turbo cup, GT world championship. I can rule out the 4WD challenge, and of the other two, I might think it's the World championship.
However, I'll give you the break down on both races.
Here's what I did.
GT world Champ.
This won't help much, but I'll offer the info.
I used an NSX, with nothing more than an oil change, and a racing muffler. Ran it on Medium hard-slicks, with ASM + 4; and TCS= 0.
Special Stage Route 11
Focus Rally Car: + 1.115
Impreza Prototype: + 1.164
Celica Rally Car: + 2.216
Impreza Rally Car: + 2.530
Corolla Rally car: + 3.734
Best Lap: 210.697
Keep in mind that it's likely the AI cars will get a boost and you'll only be ahead by 1-2 seconds. So, it is imperitive that you avoid hitting halls, and race very clean.
Turbo Cup
Special Stage Route 11
I jumped in to my Silvia K car grabbed an oil change and added a Semi Racing Suspension, sports brakes, chip, racing Muffler, stage 1 turbo, Racing Intercooler, super slicks (didnt really need), and stage 2 weight reduction. This wasn't enough.
I then Picked out a Stage 2 turbo, port polish, Racing Flywheel and full LSD. And I needed all of it. If I hadnt cut off the 3000 in the last hairpin, he might have won. Autosetting = 27 (should have been 24), HP 294. I basically bottom out the suspension, and adjust the ASM=2, and TCS=1. Set the gear ratio accordingly.
3000gt VR-4: +0.854
Skyline GTS-t Type M: +3.094
Silvia K: +4.294
240SX Fastback: +6.164
TT 1.8T: +8.007
Best Lap: 219.230
This win netted me the ever so important Daihatsu TR-XX.
You have to run this race very smooth. You lose massive amounts of time in the corners if you hit a wall. This may be where you are having problems.
Hope this helps.
AO