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Thread: P11 Auto-X Setup help

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Posts: 161-170 of 220
2016-11-07 15:02:43
Got Third Place in the unlimited class with the r888 and for my first time with um that feels really good. Competition was tight and I was in a field of lightweights! Says a lot.
Need to setup a bit more rotation in the rear not that all corners are the same tire and size. Handling is neutral but towards understeer. Rear inside tire lifts which it normally does even on street tires too.

I was thinking of lowering the front a bit to get more weight towards the front(get more traction accelerating/decelerating, should promoting some lift off oversteer) and then put back the front sway bar and weld some adjustable arms so I can go softer than stock. Any advice?

2016-11-09 19:52:09
sample video of the April event

And another quick sample video for this past event on Nov 6th when I ran with the r888.
Last edited by cayman_primera on 2016-11-09 at 19-57-03.
2016-12-02 14:08:39
The last event for the year came in third place again proving that this setup is working very well. I re-installed my front sway bar, made these brackets to tie in the heim joints to the third link. I will post picture of the setup all bolted up later.
Front sway bar and upgrading the bolts for the panhard bar chassis mount was all I changed for this event as the car was very neutral before. Front sway bar helped with keeping the car from lifting the rear inside wheel on hard turns, still lifted a bit but not as much.
Here are some vids from the event, from inside the car.
The last vid is the fastest run, feels that I could have gone faster on the last lap on my last run was a smashing time, if I could have done two laps like that I could have placed 2nd

Sorry for the rattling in two of the videos, forgot my breaker bar on the floor under the seat.
Looking forward to next year, Things to do for next year are: Bigger r comp tires, going with 255 Nitto NT01 all around, Roll centre and bumpsteer correction. Adjustable LCA( Heim joint to adjust camber etc.) and hopefully some tuning to extract some more low end performance.

Let me know what you guys think.
Last edited by cayman_primera on 2016-12-13 at 18-20-41.
2016-12-16 01:56:54
I'm on the tail end of all this in this post. I've been autocrossing for just over 20 years in nissans now. Ask anyone in the SMF or similar classes in the USA about setting up a fwd solo car and they will tell you the following: 1. Get a good mechanical diff immediately. (mfactory is on sale now)
2. Max negative camber up to 3 degrees or so if possible with 1/8 toe out front, zero toe and a bit of negative camber rear (beam bending, anyone?)
3. Get hoosiers...the tires you're running are nowhere near the performance of them.
4. BIG rear bar, stock or no front bar
5. Repeat...Get Hoosier a6 or a7. With a 9 inch wheel. Most use the 275-15 front and the 225-15 rear...myself included when I ran FSP. (I pinched them on 8"rims) honestly, 17s are HUGE for a modded fwd autox car
6. Make sure you get shocks that are valves to your desired Spring rate or more. They can't keep up with stiffer springs if they aren't valved for them. Koni yellows/gc: revalved by truechoice were AMAMZING I was running 475f 425r on my B14 and the OTS konis needed to be revalved for even that low a rate.

Then you just tinker with tire pressures and shock settings to suit your driving style!
2017-01-24 15:06:52
@ian Those advises are good for most FWD cars, but sadly they are much harder to actually utilize on the P chassis.

2. Max Negative, up to 3*: Our cars come with 0* camber stock and not easily adjustable. Shorting the UCA's 10mm will gain you about -1* at stock hight, gained me -1.3* at 1" lower. Going shorter then 15mm can result in 3rd link contacting the body. Over lowering is the only real way to get that much camber, but then you get bumpsteer and a bigger roll couple (no roll center kits for us).

The camber curves on our stock suspension are also pathetic, coupled with low caster an high KPI we stock suspension can get into positive camber at full lock fairly quickly.

4. Big rear bar: Biggest we have is A32's addco's at least they are solid and adjustable. When I first installed it on my car it didn't help at all, car still was an understeering pig. Only after modifying the front a good bit, doing rear suspension work, and coilovers with rear's being 2k stiffer did my car finally start to get loose when I reinstalled the rear swaybar.

5. Get fatter Tires: I don't believe 275's will even fit, the pesky 3rd link is in the way. I went with 225/45/17's on 7.5" +40mm wheel (stock is +45mm). I was starting to get pretty close to the 3rd link, +40 helped with that, but I had to roll and pull my fenders. Also that tire combo would still rub against the engine bay and my 6 speed trans.
2017-02-26 14:29:34
Ahh well indeed I am not familiar with P-chassis and did realize the clearance issues. Spacers?
2017-03-13 16:44:02
I use 20mm spacers with the 255/40-17 setup on g35 17x8 +32 wheels and still just rub on the inside. Not a huge issue. My setup now makes the car very neutral when I use the same size tire all around, staggered setup makes it a bit snappy. I would love a ned diff but not in the budget right now
2017-03-15 17:40:38
Started on my LCA project with a spare set I had, spherical bearing ball joints for RC Adjustment and Heim Joint for the forward inside mount to have some adjustment there as well to dial in camber etc. the rear mount for now will be a stock oem mount. will keep up the PICs as I go along.

Last edited by cayman_primera on 2017-03-15 at 22-15-16.
2017-03-15 20:16:04
Pictures seem to be down, would love to see what you did.
2017-03-15 22:15:56
Hope it works now, if not there are links to the photos as well
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