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Discussion Starter #1
Folks that autocross P11's that have coilovers or much stiffer spring rates then stock, how do P11's compare to other cars? I used to autocross my p11 but with B&G's it was a dog in turns, too soft for car weight.

I would love to try the car with heavier spring rates, (6k-8kg) and see how it does, but don't want to spend $1k on car that I might end up selling anyway.

Here is some pics of P11 pigging around with B&G's or Tein's and Bilsteins... car needs stiffer springs, this is why I bought a B15 and put BC's on it, but now am tempted to make P11 be the racecar.


 

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I autocrossed a p11 for a whole scca summer season i was considered a novice because it was my first season and was the first place novice at the end of the season which i was very proud of. I was in stf class i had a hard time winning against my competition mainly a prelude and a focus svt which had significant more power and way better tires they had r compound i was on all seasons so big differance their but i was still 2-4 seconds behind them. I had 225 all seasons bolt ons i/h/e took off front sway bar put in rear sway bar front and rear strut bar bc coils with 8r/6f spring rate which wasn't stiff enough. At the end of the season i gave up on the p11 i wanted too move too smf and figured p11 would not be competitive, so i sold it and got a p10 by the summer it will be turbo and have slicks i feel like it will be competive and it handels way better then my p11 did. If your serious about it go withh the spec v or get a p10. My friend autocross his spec v and it does very well
 

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Discussion Starter #7
P11 is a heavy pig compared to the p10 and unless you want to start a major weight loss diet, you won't escape the 'heavy sedan' issues.
I know we all joke around P11 being pigs, but they are still lighter then WRX's, modern Civic Si's, yet those two handle extremely well. A friend of mine had a stock 2009 SI that he would race with excellent times (slicks or not), so that's not even counting PAX scales.

A lot of people will get butthurt over this, but our suspension designs are ancient overall, my 05 Legacy GT has 400lbs on P11, Mac strut front, stock everything, and it still handles miles better then even a bolt on P11.

I autocrossed a p11 for a whole scca summer season i was considered a novice because it was my first season and was the first place novice at the end of the season which i was very proud of. I was in stf class i had a hard time winning against my competition mainly a prelude and a focus svt which had significant more power and way better tires they had r compound i was on all seasons so big differance their but i was still 2-4 seconds behind them. I had 225 all seasons bolt ons i/h/e took off front sway bar put in rear sway bar front and rear strut bar bc coils with 8r/6f spring rate which wasn't stiff enough. At the end of the season i gave up on the p11 i wanted too move too smf and figured p11 would not be competitive, so i sold it and got a p10 by the summer it will be turbo and have slicks i feel like it will be competive and it handels way better then my p11 did. If your serious about it go withh the spec v or get a p10. My friend autocross his spec v and it does very well
Wow so with 6f/8R and it still dogged? That kind of sucks. I always race SM/SMF, no kiddo stuff :naughty:. Thus my P11 was SMF, because of turbo and suspension changes, but all bolt on springs are sucky imo.

I currently have an 2001 B15 SE w/PP, DET, T25, BC coilovers 6F/7R. It handles really good, but still has beam issues at limits (front outer tire gets overloaded). It did improve when I made front spring rates be softer then rear.

B15 is a cheap car overall though, cheaper interior, less comfortable. Thus it sucks to take it on long trips to the SR20 conventions, but at least it has somewhat usable cupholders! Another thing against B15 is ability to put down power, P11 is able to put down power much better in straight line, while B15 spins tires. This is because of static negative camber and car weight mainly.


B15 racing pictures:




 

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Discussion Starter #8
@bballmanath What was your biggest issue with the P11 handling wise, was it refusing to turn, rolling over the front outer wheel, body roll?
 

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Biggest issue was simply understeer. Seems like no matter what i did that was always the issue i got it too oversteer like twice. It wad still a fun car to drive and at the end of the day comparing times i would always beat sti/evo/s2000 but they were stock
 

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Discussion Starter #10
Biggest issue was simply understeer. Seems like no matter what i did that was always the issue i got it too oversteer like twice. It wad still a fun car to drive and at the end of the day comparing times i would always beat sti/evo/s2000 but they were stock
What tire pressures where you running? Stock rear beam too? Bending the rear beam helped me oversteer a ton more on my B15 (B15 and P11's have 1/8" toe in). Running 7k rear springs, 6k front springs helped with oversteer more, but what finally made it really oversteer is 40psi rear tires, 30psi front.

I was always told to run higher front then rear, and that's good and all but the car would just understeer, running higher rear PSI helped the tires loose traction first.
 

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Hmm never heard of higher psi in rear but makes sense ill have too try that with my p10 im still new too racing. And yea stock rear beam i dont remember what psi i ran but i know i ran the same front to back so that could of solved my problem
 

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Understeer is/was also the biggest issue for me. It made the car seem unbearable.
But i run 8k/6k for the AutoX, and my car is felt super nippy, i would suggest a setup like that.

The last 2 runs are the ones i would pay attention to, that was my first time ever doing Autox and im on all season firestones that were absolutely garbage. But if you pay attention you can see how little roll my car has. The only problem was i was overdampened for a bit, and thats why you can see the rear wheel bouncing a bit.

As a comparison, this is my buddy who i go with. He also has a linear spring setup (not coils) with dampers that are actually a bit too stiff for the spring. I believe hes around 350lbs/in
http://www.youtube.com/watch?v=sdpANwREqNc

This was before he added negative camber playes up front.
But i actually REALLY liked the way his car drove on the autoX, it felt like it had give, but still would hold tight (this was WITH -2* camber up front). As oppose to my car which would feel good, but the understeer happens more harshly and isnt as easy to identify.
 

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Discussion Starter #13
Where you running 8k front 6k rear? With motion ratios, I would say run 8k/8k, you want your front have lower wheel rates so that more weight stays in the back. I gotta sit down and measure P11 actual motion ratio, Sarah Frost has said it was .7, then some forum members have said it was .87, need to know for sure before I buy new coilovers.

BTW your second vid is the same as the first one.
 

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Sorry, theres the Golf,

Yes 8k front 6k rear, which i blieve is how Ksports come from the factory, i plan on changing my spring setup to something more equal.
Right now i Have Stechs in front and 8k in the rear, i quite love the feel actually. Once i do my tranny swap ill AutoX it with 205's and see how it feels.
 

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This is a video from Temuco, Chile in interlomas circuit.
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My car Nissan Primera P11 SR20DE RR with eibach spring, fron and rear strut bar, 4-2-1 header

Here in this flickr you can see some pictures of the track
 

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Hi,

Mi engine is 100% stock, with header 4-2-1 and line in 2.5" without catalytic system in the future i will install turbo kit for my p11 or SR20VE engine with N1 cams i don't know really
 

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I did scca solo(NYR) last season and ended in 1st Novice class :)ditsy:) . Im in STF with the p10 on d2 coilovers,addco rear sway, and falken azenis tires([email protected]&43psi). engine all stock, extremely hard to keep up with the rsx and civics, but im a rather skillful novice . There was another p10 at a couple events with a det but crap tires .... TIRES ARE KEY !
 

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Discussion Starter #20
Picking this back up. Already have Cusco UCA's on order, next is coilovers. I'm thinking about going with 600lbs front/rear spring rates. This should give me around 454lbs front and 600lbs rear wheel rates, with rear being 24% stiffer than front. Mike Kojima used around 20% stiffer rear for his Sentra race car.
 
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