Autocrossing an s13 for fun on $1200/year

Greetings. I've begun to formulate plans to transform my almost bone-stock 1992 240sx hatchback into an even more fun autocross car. Here's what I've got in mind.

I've owned my white hatchback (base model) since about 2000. It was my daily driver in college and was only relegated to "spare car" status about three years ago. It's just shy of 200,000 miles and has been very reliable over the years.

I've been to a few autocross events now and I know it's something I want to stick with. I don't expect to be competitive as I'll likely only be attending 4 or 5 events every season. I enjoy the driving more than the competition. One of my current upgrades (suspension bushings, see below) places me in the Street Touring class, I think. Reading the rules, that seems like a place I can play for the next few years even if I'll be under-prepared for a while.

My requirements: (1) Enjoy driving the car. I'll be driving up to 2 hours to get to events and don't have a trailer for tires, so a super-stiff racecar with a stripped interior and R-compound slicks isn't what I'm looking for. (2) Upgrades/modifications total less than $1200/year. (3) I want the car to "feel" and handle great even if it's not the fastest. (4) Keep it looking relatively stock. Slightly lowered is fine, but I don't want to compromise the suspension geometry.

What's already done Hawk HPS front brake pads, Brembo front rotors, Whiteline front control arm bushings, Whiteline front tension rod bushings, K&N drop-in air filter, gForce SPORT Comp-2 tires (just purchased and installed), OEM 7-spoke alloy wheels (currently with gunmetal gray Plasti Dip to hide the horrible curb rash),

My plans (2014 season) Front sway bar: Progress 61.1502 3-way adjustable with solid endlinks. $250 shipped. Lots of sources say that better sway bars are a great bang-for-the-buck upgrade. I like the adjustability and plan to keep the stock rear bar. Strut tower bars: Stealth Fabrications bars, if I can place an order. $220 plus shipping. These look very well-made and seem to be the most rigid of all that I can find.

(2015 season) Shocks: Koni yellow all around for $500 + shipping. These seem to be the best bang-for-the-buck shocks. Coilover conversion kit: Ground Control 6065 for $450 + shipping. Not sure on the spring rates yet.

After that, I'll might be up for engine/drivetrain modifications (supercharger, intake/exhaust, etc.)

Apologies for the run-on sentences above. It looks like I need to learn how to manage the formatting syntax here.

clean car!!!! PLZZZZ no bodykit! oem is so pretty :). GL and invest in a sony action cam or video device :)

Actually, most of the classes in SCCA autocross require a full interior so most people don't have to strip out their interiors to be competitive. Do you want the car to feel really responsive on the street and track or just on track? If it's just for the auto-x courses, wait until you've raced enough to know what exactly you need for your car, for your particular driving style. Also, forget the supercharger unless you really need 50-100% more horsepower for the street(track too). A super or turbocharger added to your car automatically places you in the Street Modified class, which is a fairly unlimited rules class, and can sometimes discourage people from participating depending on the local hotshoes. Since you're doing this for fun, I would personally skip the Ground Control coilover conversion kit and just get Eibach or another good brand of 1" lowering springs. They will be much less expensive. You also have a good, fresh set of summer tires, so you should be fairly satisfied with the handling and fun factor of your car for this season. Remember to have fun.

Good 200tw tires will do more for you than anything else. I got 10k miles and 20 or so autocrosses out of my first set of StarSpecs. Most of the current tires should be similar. After that, learn how to align your car with strings and tape measures and patience. THEN think about that other stuff.

i agreee on jackstands, kite string, and a tape measure alignments!!!! lord that stuff works!

Are people still playing with the idea of supercharging KA's? In the early 2000's on zilvia.net I can remember the theories and discussions. My $0.02: I wouldn't mess with the KA if going for power. You have plenty of room to grow with a limited slip, suspension, tires, brakes....etc.

When you are ready for more power SR, CA, RB, LS.....the options are endless but I find most 240 owners don't push the car hard enough with stock motors anyway before they go for more power. I had the most fun with a t28 powered SR S14 and a rb25 turbo on an rb20 in an R32. Hi revving, fast spooling, metal head gaskets with oil squirters motors that are easier to keep together long term than a boosted KA.

On the contrary, i'd stay with the KA if power becomes a consideration.

Less work, makes plenty of power under boost, spools things faster than SR20. And compared to the RBs, retains better balance.

Swank Force One wrote: On the contrary, i'd stay with the KA if power becomes a consideration. Less work, makes plenty of power under boost, spools things faster than SR20. And compared to the RBs, retains better balance.

I'll disagree with that point just rebuilding 3 KA turbo over the years for cracking rings. After the machine work and forged parts, it was more expensive than the SR's I never had to open up.

For autocross you don't want anything bigger than a t25 or t28 and an SR spools those almosts instantly. Not noticeably different than a KA.

RB's rev to the moon which is ideal in 2nd gear on an autocross course and I never felt a difference in balance in an RB swapped car over a KA turbo car.

My main focus really is fun and an excuse to do some wrenching on the S13. I don't have the time or inclination to devote to autocrossing seriously. Any modifications I make will have to be livable getting to and from the site. I don't want to deal with the hassle of switching out wheels/tires when I arrive. I recognize that someone else will always be on better tires and will probably beat my times. I'm okay with that. Thus, I went with the gForce Sport Comp-2 tires because they were summer tires with reasonable performance in the rain and could be found in nearly my size for about $75 each. The 240sx is a third car in my house, so it needs to be somewhat available in case a daily driver needs to visit the mechanic.

Forced induction is definitely far down the road from here, if ever. It would be for the fun of installation/tinkering instead of for the strictly by the numbers power/$ benefit.

As for string + tape measure alignments, can you point me in the right direction? I recently replaced the tie rod ends and a few other suspension joints. Things seem to be aligned well, but it couldn't hurt to check (particularly with new tires and wheels).

Aren't you supposed to drift those things?

FWIW, swapping wheels on site isn't that bad a hassle, I'd do it for my meotter if I had a way of actually transporting a spare wheelset with it.

Ooooooo I like this topic! I have about 7 years autocross experience with an S13, so I can help you out with some of this stuff.

First off, the Koni/Ground control setup is awesome. I used off the shelf spring rates and was happy with the car. With my driving style it pushed a but at the limit, but it was easily controled by a slight throttle lift.

Second, you'll need some adjustable spenshun pieces to get the alignment in check after the koni/GCs. At the very least, rear upper control arms and rear toe arms. Front tension rods (controls caster) and camber plates will make for a well adjustable car.

Third, a good LSD rear. Stock VLSDs are OK, but will still get inside wheel spin on occasion. An s15 helical diff is the way to go for an autocross car.

Fourth, buy an S15 steering wheel. Now. It was easily the favorite thing I did to that car

I'm looking forward to watching this car evolve!

Interested to get impressions on the BFGs since I just bought a set for my wrx today. I kinda wonder whats wrong with them since they are suppose to be better than the dunlop dz101 and other comparable tires and they were cheaper than all the rest at 96 a tire for me. The wrx will mostly see spirited daily driving but we all know that it will probably wind up at an autocross sooner or later

When I was auto crossing the wrx before my miata what I did was first, tires. Second, big front sway bar. Third, max camber up front ( i had access to a machine ). In the miata I ran my dz101s that it came with for awhile with maxed out negative camber all around. I upgraded to a corbeau racing seat which I believe is legal in street touring as well ( I'm in CSP due to a aftermarket steering wheel that came with the car ). The seat was about $300 and I find it more comfortable than the stock seat was. As for suspension I was looking at konis and ground control coil over kit as well but that will be later.

It sounds like you got it all under control. Go have fun, drive the car and slowly add parts as you see fit. I'll be watching this build!

This is gonna be a good build I cant tell you how relieved I am to see a 240 do something other than drift. I will thoroughly enjoy watching this come together.

Not only is my s13 active in auto-x, I still run a (built) KA24E SOHC in it. Was able to easily claim the San Diego Region Street Modified championship in 2013. First picture is me at the SCCA National Tour last weekend. It was like taking a knife to a gunfight, but somehow held it's own. The only two cars that were able to best me were a National Champion in an S54 swapped e36 M3 and a Nissan GT-R. This was with (maybe) 150whp and 1.5 year old (50+ runs on them) Hankook Z214 225-45-15s. The Bimmer was on 275 Hoosiers and the GT-R was on 345 Hoosiers. If I had the money for more power and more tire, who knows what could happen.

It's a good chassis. We need to steal them up from the drift dorks and run them properly!

^very cool

I love the pictures, Cone_Junkie. Spoolpigeon, you wouldn't want to sell that Ground Control setup would you =) ?

I posted here because I figured there were like-minded folks with experience I could learn from. Now I've met a few! Unfortunately the association between drifting and the 240sx is so strong that most Google searches I make looking for advice rarely end up with well-reasoned opinions on what works for grip driving. The signal-to-noise ratio on this site is much higher than most other forums I've found.

I'm headed to an autocross tomorrow and the weather looks perfect. I'll report back on the g-Force Sport COMP-2 tires. Although the tires I just took off are old, worn-out all-seasons, so I'm sure the COMP-2s will feel like R compounds to me.

In reply to vsquaredbyrho:

Sold the car 2 years ago. Sorry.

And I completely agree about the noise on the 240sx forums. There is so much BS to dig through to find any decent info. I ended up just saying the hell with it and getting the koni/gc's without finding any real info on it before hand.

One thing that does suck about the rear Konis is that you have to take the strut off the car to adjust it. It took me about 4 autocrosses to get them where I wanted, which was about 1 full turn from the softest setting (of course that will change for driver preference). I had a HICAS model rear sway bar on the car, so it didn't need a lot of rear shock.

In reply to Cone_Junkie:

LOVE IT

Check out nissanroadracing.com, small forum of guys mostly doing autocross and track events with 240SXs. Lots of good info, little nonsense.

turtl631, I've used nissanroadracing as a great forum for reference, but the folks there seem to be much more hardcore than I am. I do occasionally peruse their for-sale section hoping to catch a great deal on some used parts.

BFG g-Force Sport COMP-2 tire review

Autocross conditions: Temps were in the mid-70s, partially cloudy, and very windy. It was a great day to be outside. We had 6 runs with my times in the 50sec range. The drive to the course was about 2 hours long on state highways and an interstate. I had about 200 miles on the tires when I got to the course. The tires were 195/55R15 size instead of the correct 195/60R15 size, so my gearing was different than stock. On the interstate, my GPS indicated 70mph while my speedometer read 80mph. At other speeds, the speedometer seemed to be reading about 10% higher than actual. [stealth edit for poor wording]

On the course, the g-Force Sports were fantastic. They were audible when approaching grip limits and still very controllable past that limit. I consistently overcooked a few fast corners and was able to use the throttle to swing the back end around a bit without spinning. On the slaloms, the response was quick and I felt able to place the car where I wanted it to go. I'll have to check the results when they're posted, but I don't think I hit any cones the entire day. In places, I understeered because I was asking the front tires to turn too quickly-- driver error instead of tire weakness.

I started tire pressures at about 39 psi front and 38psi rear. An experienced autocrosser looked at the sidewalls after my first two runs and recommended I drop the pressures a bit. I ended up running the fronts at about 36psi with nice wear marks down to the edge of the tread. I dropped the rears down to 34psi and the wear marks were still up fairly high. I didn't think dropping the pressure below normal inflation pressure would be a good idea for autocross, so I left them at 34psi. My conclusion is that the advertised "g-control sidewall inserts" work pretty well since I did not have excessive sidewall rollover even at fairly low pressures.

Conclusion: For autocross tires that you can easily drive to and from the track, have fun on course, and get in near-stock size for a good price, I'm really satisfied with the g-Force Sport COMP-2. I usually place very last in the G stock class, but I believe I made 4/6 yesterday. I believe that the tires were mostly responsible for an improvement in my usual times.

Caveat: My previous tires were Bridgestone Potenza g009 all-seasons that were about 7 years old and nearing the wear bars during my last few autocrosses. Most of the above-mentioned improvements might be true for any summer tire, as this was not a scientific test.

In reply to vsquaredbyrho:

Thanks for doing the review on the tires. I've had mine on my wrx ( 225/45/17 ) for almost a week now and first impressions are the sidewall is softer than my old dunlops. I'm going to run them tomorrow doing a time attack at a local go kart track so I figure ill probably try 40-45 psi at first and bleed down from there just to be safe. Subaru is front heavy and likes to eat weak tires.

I lost my cooling fan, radiator fan, and radiator today from hitting a bump. The distributor wire came loose from the connector and got tangled with the cooling fan causing all manner of havoc.

I was two blocks from home on my way to a Sunday autocross with a perfect weather. As I pulled out onto the main road at 6:45am, I hit the transition between the side street and the main road at less than 5 mph. Before I even shifted into second gear the horrible noises came from under the hood. My engine was dead and I had no power steering. Fortunately, I had enough momentum to coast to a side street where I pushed the car into a parking lot-- glad that my town is very flat.

With the hood open, I immediately saw something had gone horribly wrong:

Three of the four bolts holding the cooling fan to the water pump pulley had sheared off. With a flashlight in one hand and a 10mm wrench in the other, I managed to remove the nut on the fourth bolt and get the fan out along with the power steering belt. That's when I saw the damage a projectile fan can do [taken back in my garage]:

There should be a bracket here holding the radiator fan and motor in place. The radiator fan was still stuck in the shroud, so I recovered it also. I plugged the distributor wire back in and drove back to my garage with a leak in the radiator and no power steering. The wire and failed electrical connector that caused it all:

At the very least, I need a cooling fan coupling, the bracket that holds the radiator fan in place, and a radiator repair. I'm trying to decide between three different repair options:

1) Cheap and possibly slow-- scrounge used parts from a junkyard. There's not many 240s around here, so I would probably have to find a compatible design from another 90's Nissan.

2) Expensive and quick-- call the Nissan dealer for OEM parts so I can retain the stockness of my S13.

3) Expensive and possibly better-- since I'll be replacing the parts anyway, upgrade to a performance radiator and maybe electric fan. Finding one that's not flashy, fits well, and works well might take some time.

No matter what I do, I'll probably remove the air conditioning system while I'm at it. It hasn't held pressure in years and is just dead weight. While I've got the radiator out, are there any other things I should inspect/replace?

Rock Auto has replacement radiators for $70-150. They probably have lifetime warranties on most of them, might be easier to just get one of those or one from the local AdvancePepZone. I definitely wouldn't pay the coin for a Nissan one from the dealer. Either that or upgrade to an all aluminum one.

My long-term plans include the possibility of some kind of forced induction. Is there any downside to getting a slightly better radiator right now in case that future comes to pass?