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240Fubs
04-26-2014, 09:00 PM
Hey guys, pretty new to the forum and the 240 world. I just bought a 91 hatch with a blacktop sr20 and am very interested in autocrossing it. I bought a set of Fortune Auto 500 series coilovers and I was wondering what you more experienced people think is the best way to set up the suspension for this specific car (like ride height, camber, etc). I plan on installing them myself sometime soon and want to adjust them in a way that is best for autocross. Forgive my overall lack of knowledge!
Thanks

UniqueAutoCreations
04-26-2014, 09:54 PM
I don't know what the best autocross setup is but if you keep your drop around 2" it shouldn't mess up the factory suspension geometry up too much. Any lower than that and things can get expensive in a hurry to straighten things out again. S13's seem to really love front camber so 2-3 degrees to start out with would probably be good and crank in 6-7 deg. caster. Caster is free camber without the tire wear and loss of straight line braking. Rear tow could be set 1/16 in for some added grip and front should be 0 to 1/16 out for good turn in response.

Also you may want to check into some Isis control arms to go with your coilovers. They are, in my opinion a really good bang for the buck. I've run a set on my daily now for a year and they have preformed really well. Also I think the Fortunes are pretty good too. We're running a set on one of our project cars right now and they show promise, although it's hard to get a car to set high enough especially in the rear with the stock lower hats. And replace the rear cradle bushings with Energy Suspension S14 ones. You have to remove just the rubber middle section and maintain the outer steel sleeve to use them but once you get them in there it's really worth all the effort. Replacing the remaining bushings and ball joints, wheel bearings, and steering rack bushings would be good too. And don't forget about overhauling the brakes too. Braided lines really help out there along with a master cylinder stopper. Those two really crisp up the pedal. I'm a big fan of maintance if you can't tell. These cars are 20+ years old now so they need some love if you plan on driving it like you stole it.

These guys however are experts. All they do is set up cars for road course use and they have experience with the S13 chassis. Give them a call. I'm sure they can steer you in the right direction http://texastrackworks.com/

Hope this helps

heychris
04-27-2014, 12:08 AM
If you are into autox I would HIGHLY suggest you check out the NRR forums (nissanroadracing.com). Lotsa guys there auto crossing and tracking their own 240's...

The best suspension by far for our cars is a KONI or Bilstein insert with custom adjustable spring perches. Lotsa info @ NRR on this setup. JDM fabulous coilovers pretty much suck for everything except drifting....

As far as replacing all the bushings with Energy pieces, that is a no no....

Again this is covered in depth on NRR, but the short version is they don't have enough deflection in multiple planes to do our suspension right...

Do yourself a favor and get over to NRR and start reading..

Cheers

Ch

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bejota180sx
04-27-2014, 12:48 AM
Like heychris said, NRR is more grip/track oriented than zilvia and other Schassis forums. Seeing you already have a bought setup, my recommendation is forget fitment and forget slamming the car, everyone has a different setup for the driving style they have, but start by setting it up a normal stiffness and obviously lower than stock height. At a track day start seeing how the car responds and go from there, lowering it more, stiffening it more and so on.

Start saving up for quality components, but in the mean time i have very very good experience with isis. Not because they are good, but because enjuku always checks them as best they can before selling anything. It eliminates much of the hit or miss from buying entry level stuff. But don't expect them to hold up long or perform as good as quality stuff like SPL and so on.

for setting when you get an alignment, depends a lot on your wheel/tire choice most of the times, but don't go insane with camber 2-3 degrees like said above is what most people tend to prefer, play around with caster to you liking as I've seen everyone prefers something different with this, and keep toe to a minimum and 0 up front.

and as a side recommendation, besides suspension i ALWAYS emphasize on how important cooling mods and proper setup/ducting is important for these cars on both KA/SR engines. This avoids a lot of headaches and downtime during extremely hot track days.

240Fubs
04-27-2014, 12:53 AM
Just want to thank all of you for your input. I'll definitely give them a call uniqueautocreations, and thanks for pointing me in the direction of NRR forums heychris. to bejota180sx and heychris, i have the coilovers but have not installed them yet, do you think its worth selling them and exploring other options? what would you have gone with?

240Fubs
04-27-2014, 02:31 AM
Oh I should mention, the price range would be around $1000, or around whatever I could get selling the fortune autos, which also have swift springs (another thing I forgot to mention)

heychris
04-27-2014, 09:17 AM
Depends on the coils. Some of the KONI/Bilstiens fit the JDM Tyte coil bodies so those FA coils might work for you. Also some guys have run off the shelf coils with good results. My car is currently on Stance coils which I bought before I knew about NRR. If I were to do it over again I would go the KONI route and buy ISIS arms. The ISIS arms are easy and relatively cheap to upgrade with race quality ends.

There's several guys on NRR with BUILT 13's. They know their stuff over there..
Good luck!

Ch

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240Fubs
04-27-2014, 01:50 PM
Ive been doing some reading about the koni route, and theres something I dont understand. Some posts have lead me to believe that the only things needed would be these ground control coilover conversion kits and the struts themselves:

http://www.ground-control-store.com/products/description.php/II=73/CA=93

http://www.ebay.com/itm/KONI-YELLOW-SPORT-SHOCKS-STRUTS-SET-89-94-240SX-S13-/320717969597?pt=Motors_Car_Truck_Parts_Accessories&hash=item4aac47d8bd

But then I see other posts that talk about there being fabrication involved in getting everything to fit. Is this fabrication only for people who choose to put the struts into the stock housing/other stock components?

Excuse my limited knowledge - would also appreciate any good sources to educate myself on suspensions in general if possible

240Fubs
04-27-2014, 01:51 PM
This is one of the write ups on the install that required fabrication:

http://www.nicoclub.com/archives/koni-yellows-install.html

Did he need to do all this because he chose not to buy the ground control conversion kit?

bejota180sx
04-27-2014, 01:57 PM
since you don't have any experience with this chassis and different setups, FA is a decent entry level coilover for your needs. When it's time to upgrade you can save up for something like off the shelf KWs or a custom Koni setup.

For the Koni setup you COULD order the groundcontrol setup and ask for a upgrade from the yellows to whatever you choose, OR you could get veilside180sx brackets and build your own setup.

240Fubs
04-27-2014, 02:02 PM
You say I could get the ground control setup and ask for an upgrade from yellows-- why would I do this? I know yellows are definitely not the best from koni but I was under the impression they are still damn good, no?

Silverbullet
04-28-2014, 06:52 AM
if your spring rates will be 8kg/mm (450lb/in) or under, it is probable that you won't need to "upgrade", unless you really want to be able to adjust both rebound and compression independantly.

It's likely Koni sport Yellows are all you need and will outperform all of the $1400 and under off-self coilovers.

e1_griego
04-28-2014, 06:51 PM
Don't worry about the parts, just start getting seat time.

Most important part of autocross is the driver. Best prepped car with the worst driver is going to get worked over by a great driver in an underprepped car.

Most of us didn't start down this path, but it's really the 'right' way to get into the sport.

If you're going to get more serious about autocross, recognize that a lot of parts will start dumping you into higher classes (= more competitive/expensive to compete). Metal bushings take you right to Street Modified, for example. If you're just running for fun, then no worries.

As for as alignment, put in 2.5* (or more, if you want) of camber in the front, 7* caster, 0 toe. (assuming this is not a dedicated car). In the back 1-1.5* camber and some slight toe-in -- 1/16" or so.

Tires are the next most important part of autox after the driver, but you will learn a lot even on mediocre tires. I spent my first two years on 595s and they're fine to learn on.

bejota180sx
05-03-2014, 05:09 PM
Don't worry about the parts, just start getting seat time.

best advice here.

As for the question on why to upgrade from yellows, since you got already some decent entry coils i was thinking about a future upgrade, if your upgrading why not spend a bit more for some more performing inserts. They can be more precisely adjusted, you might not need this really it all depends on what YOU want and how much you know about setting up the car for you driving skills.

240Fubs
05-03-2014, 09:57 PM
thanks a lot for the awesome feedback guys

heychris
05-04-2014, 10:54 AM
e1.......speaketh the truth....

Ch

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KA24DESOneThree
05-04-2014, 02:13 PM
Keep in mind that seat time is only helpful if it's quality seat time. If you don't know what you're doing and keep going to track days, you'll get better, but you'll still have bad habits. Try to get seat time with an instructor for a couple days and you'll likely see vastly improved lap times and you'll have a baseline from which to improve.

Good input= good output. Flawed input= flawed output.

e1_griego
05-04-2014, 03:30 PM
Track days, yes. Autocross is pretty clear when you're fucking up or not lol.

The clock doesn't lie :)

!Zar!
05-04-2014, 05:40 PM
In addition to seat time, the seat you spend time in is important as well.

Trying to drive aggressively in a stock s13 seat is a pain. Hard to focus on being smooth when you're fighting to keep your body still.

240Fubs
05-06-2014, 01:45 AM
^i assume this is the reason a lot of people opt to switch to s14 seats

Frank_Jaeger
05-06-2014, 10:44 AM
I've sat in S14 seats and sat in leather and cloth S13 seats and the S13 cloth bucket seats are much more secure. Someone offered to trade his S14 seats for my S13 seats with $20 on top and I told him no. The S14 seats push you off of them where the S13 seats you sink into.

I don't understand why people hate the bucket seats so much. They're snug.

Now obviously any quality aftermarket seat is going to provide better support, but I don't see how S14 seats are an improvement. I think people like to swap them in simply because they're newer and thus an "upgrade."

e1_griego
05-06-2014, 10:52 AM
^Agreed. s14 seats are just flat and I suppose more comfortable for trips.

s15 seat or r32 gtr are my favorite nissan oem seats for s-chassis.

Future240
05-09-2014, 02:43 PM
^Agreed. s14 seats are just flat and I suppose more comfortable for trips.

s15 seat or r32 gtr are my favorite nissan oem seats for s-chassis.

I've been thinking about getting S15 seats as the S14 does go on long drives and I would like to be more steady in cornering. How do they compare to s 14 seats?

e1_griego
05-09-2014, 02:44 PM
Much more bolstering.

240Fubs
05-10-2014, 05:26 PM
yeah i'm thinking of sticking with the stock seats for a while at least. although i might want to get rid of the auto seatbelts, save some weight

bejota180sx
05-10-2014, 06:34 PM
you could use manual seat belts, get some from a s13 in canada, it's what i've used for years and they are way better than the auto seatbelts to my liking. As for seats, r32s have been the most comfortable that still offer more "holding" compared to other stock seats, you could get some Sparco Sprints they are FIA approved, decent priced and really they are quite comfy keeping in mind it's an entry level bucket seat.

racepar1
05-12-2014, 12:45 AM
In addition to seat time, the seat you spend time in is important as well.

Trying to drive aggressively in a stock s13 seat is a pain. Hard to focus on being smooth when you're fighting to keep your body still.

AGREED. The MOST eye-opening upgrade I have ever made on my S13's was the first time I installed a race bucket seat. You don't really realize how much you're hanging on for dear life untill you don't have to do it anymore. A bucket seat is ABSOLUTELY NECESSARY if you're going to regularly attend track, drift, or autocross events.

As for the urethane bushings, the NRR guys are more critical than what is necessary. If you're not going to upgrade to full spherical bearings urethane is the only route. The main issue is keeping them lubricated. There are write-ups both here and on NRR for installing zerk fittings with your urethane bushings. Well-lubricated urethane bushings present NO binding issues WHATSOEVER. I've got full urethane (with zerk fittings) in the rear of my S13 with adjustable RUCA's and toe arms. With the shocks removed I can easily compress the suspension through it's full range of motion by hand.

NRR is a GREAT resource for 240sx enthusiasts who are more concerned with actual performance than style. I've been a member there for quite some time and there is TONS of technical information accessible there. Zilvia kids are not interested in anything that's not slammed and sliding into a wall at a high rate of speed. You do have to realize that a LOT of the NRR guys are at the polar opposite end of the spectrum though and reality is somewhere in the middle. Your car does not have to be a masterpiece of engineering perfection to perform well.

As for the FA coils, those are fine to start with. I don't think it's necessary to sell them and start all over. Concentrate on putting together a well rounded setup for the ENTIRE car and pursue your ideal setup from there. A Koni/GC setup using veilside180sx's housings would likely be a good upgrade in the future. There is a lengthy and detailed write-up here on that setup as well.

As stated, seat time is everything. Seat time with an instructor is what you REALLY need though. It is much wiser to spend your money on seat time than trinkets and knick-knacks to make the car "better". Start with the basic upgrades necessary for heavy track use. ALL maintenance items, GOOD brake pads/lines/fluid, TIRES, and cooling upgrades.

240Fubs
05-12-2014, 01:35 AM
Thanks for the input racepar. I am much closer to the NRR end of the spectrum, and I definitely see that most of zilvia is all about stance and being slammed and whatnot. I think I am sticking with the FA coils for now but keeping my eyes open for a set of used KONI+GC setup. Will also keep my eye out for a bucket seat within my budget. If any of you guys see either of those things for sale i'd appreciate a heads up!

240Fubs
05-12-2014, 01:36 AM
Its sad that I never really see S13s at autocross events I go to. I guess because most s13 owners are drifters/stance kids?

slider2828
05-13-2014, 01:25 PM
Autocross competitive suspension and drift/track setups are night and day....

Autocross if you want to be competitive, you need stiff as hell suspension because you want very minimal body roll. Body Roll in such a short distance as autox makes your car transition very slowly causing you time. I think Grassroots motorsports did an article on this.

On the track or drift, some body roll increases corner grip and you need proper suspension geometry for that to translate into control of entry, apex, and exit....

But truthfully as everyone else says, seat time, proper safety gear, a well maintained car and bucket seats well get you very far along being competitive in anything you do.

bejota180sx
05-16-2014, 03:14 PM
i just wanted to point out one last thing, braking. You don't have to get bigger brakes, just better components. Get pads that can stand the heat at track days, same thing with fluid. Besides increasing performance, it's also safer to push the car to your limit and still be able to brake safely if you mess up while pushing. I've seen a lot of people starting to get the hang of things and starting to push, and then having the brakes fade at the wrong part of the track. Im not trying to make anyone feel like they don't know stuff by stating obvious things, its just in case someone is reading this thread and has no idea what to do since this has turned into a nice little introduction of sorts on what stuff to look out for.

slider2828
05-16-2014, 04:19 PM
I 100% agree with you too Bejota!

240Fubs
05-16-2014, 04:27 PM
Thanks for all the input. I've been focusing on brakes (I got some R32 brakes, no pads yet), and suspension which some of you have already given your opinions on. I also got five lug hubs and am going to run some evo wheels with RS3 tires on them. I did not realize how expensive a racing seat was though. Bride seats show up often on the for sale section but the non replicas are a little out of my price range for now, so I think i'm sticking with the stock s13 seat for now. Outside of these things and obviously seat time, what other weak points are there in the car for this purpose? I have read that people do not like the VLSD very much...

slider2828
05-16-2014, 06:52 PM
Seats are not expensive.... you can go with a sparco speed seat which is about 250 bux and then a frame slider or just base and that is about 100 bux... 100 more with a slider... Not bad at all...

Change all your suspension bushings, like energy black with have poly stuff built in so no binding....

You should be good after that.... Not much weak points....

LSD just get a Kaaz if you want to drift 2way or 1.5 for street/track... up to you

racepar1
05-16-2014, 08:34 PM
Seats are not expensive.... you can go with a sparco speed seat which is about 250 bux and then a frame slider or just base and that is about 100 bux... 100 more with a slider... Not bad at all...

EXACTLY! Forget the jDm yO overpriced Bride's and stick with Sparco. Just as good quality without the "JDM tax".

Change all your suspension bushings, like energy black with have poly stuff built in so no binding....

This is a myth. The black bushings bind when they lose lubrication just like the red's. The KEY to urethane bushings is installing zerk fittings and greasing them regularly.

LSD just get a Kaaz if you want to drift 2way or 1.5 for street/track... up to you

This is ABSOLUTELY un-necessary for autocross or trackdays. A cheap stock VLSD will work just fine, I wouldn't advise him to even think about that untill later on when the rest of the car is set up and he's got some seat time under his belt. Don't worry about getting anything more than a VLSD unless you're drifting. In that case you could get the VLSD for autocross/track and a cheap welded diff in the pumpkin to throw in for drift days. Personally I would stay away from Kaaz anyways, the initial torque is super aggressive on them and they annoy the shit out of me...

Apex Eight
08-17-2014, 12:42 PM
Bump from the dead. The black ES bushings are graphite impregnated and the red ones are not.

Great thread BTW. Wish there were more like this on here.

voiddweller
08-22-2014, 03:01 AM
Agreed. Good thread.

NRR is an awesome site. Those guys know their stuff!

A few quick points:

When going with aftermarket seats, consider a roll bar. In crash tests with OEM vs Aftermarket Buckets, OEM does better when you don't have the bar. If you have the bar, buckets hold you perfectly and you're safe.

VLSD is perfect for autocross and DD, but consider helical if you start doing a lot of HPDE's.

I'm not a huge fan of poly bushings on dual duty cars but they are great for track cars with the grease fittings. I wish Hardrace made bushings for the S - chassis. Sphericals are ideal for track but good ones are expensive.

Moore
08-22-2014, 12:51 PM
Good hear. I went to my first auto x event last weekend. I did okay, about halfway through the pack for time.

My biggest surprise was how much understeer I suffered from. My tires are not top of the line so obviously that would help but what other tricks are there to improve front end grip. I can add more chamber, would dropping front tire pressure be a good idea?

e1_griego
08-22-2014, 12:59 PM
Always more camber. Not drift-tard levels like 6*, but 3* will make it better.

More camber will allow you to drop pressure, too. You can read the edge of the tire and adjust pressures accordingly.

Also, square tire setup helps, and a bigger front bar.

Obviously tire compound is paramount for autox, so better tires will help immensely.

240Fubs
08-22-2014, 01:07 PM
^ thats awesome about your first autox. I only ran twice this season and never in my 240...preparing it has been veryy slow. Good question, would love to hear responses from these guys.

slider2828
08-23-2014, 07:22 PM
It can be helped with spring rates as well... What coilovers are you running?

Apex Eight
08-23-2014, 07:55 PM
I've read that the standard Koni Yellow x GC setup has limited travel and hits the bumpstops. Anyone have any input on this?

zooopreme
08-23-2014, 08:50 PM
I've read that the standard Koni Yellow x GC setup has limited travel and hits the bumpstops. Anyone have any input on this?

That has a lot to do with spring perch placement, spring rate, and spring length.

Assuming we're using stock strut housings, people tend to weld the perch closer to the ears to achieve the lowest ride height possible.

Sure, maybe it'll be okay to mount the top mounting components (spring hat, camber plates, etc.) but people forget that the have to consider that there is a external bumpstop, the springs compress a bit when the car is on the ground, and the strut has a job when driving. Before you know it, you've already have eaten up a good amount of travel.

That being said there are ways to combat this: custom housings or cutting and extending the portion below the ears.

With custom housings, however, you may as well just get 86XX's.

Apex Eight
08-23-2014, 08:58 PM
That has a lot to do with spring perch placement, spring rate, and spring length.

Assuming we're using stock strut housings, people tend to weld the perch closer to the ears to achieve the lowest ride height possible.

Sure, maybe it'll be okay to mount the top mounting components (spring hat, camber plates, etc.) but people forget that the have to consider that there is a external bumpstop, the springs compress a bit when the car is on the ground, and the strut has a job when driving. Before you know it, you've already have eaten up a good amount of travel.

That being said there are ways to combat this: custom housings or cutting and extending the portion below the ears.

With custom housings, however, you may as well just get 86XX's.

I see. The idea of doing all of the work to get the Konis into the housings is a bit worrisome to begin with, so the cutting and extending portion adds to the intimidation factor. Upgrading to custom housings would push the setup above $1K, as would going with 86XXs, so my question is, would it be alright to go with, say, a set of the Fortune Auto 500 series and call it a day? They are a little over $1K, but are simply a bolt-on affair. I've heard that radial bearings are a really good upgrade though. Those only go on the front coilovers, right?

zooopreme
08-23-2014, 09:18 PM
I see. The idea of doing all of the work to get the Konis into the housings is a bit worrisome to begin with, so the cutting and extending portion adds to the intimidation factor. Upgrading to custom housings would push the setup above $1K, as would going with 86XXs, so my question is, would it be alright to go with, say, a set of the Fortune Auto 500 series and call it a day? They are a little over $1K, but are simply a bolt-on affair. I've heard that radial bearings are a really good upgrade though. Those only go on the front coilovers, right?

As much as I love Fortune Auto (I've owned three of their coilovers, I now only own one), they aren't close to my Yellow Sports and S-Techs. AND I don't even have a ton of travel.

I use my Fortunes for drifting and like other coilovers I've tried/owned, they get the job done but leave a lot to be desired once you've tried Koni and Bilstein.

If you just want something to put your car low and have adjustable rebound, go with Fortunes. But if you want to make the most of your suspension, Koni or Bilstein or Ohlin or Penske. Are Koni's/Bilstein's worth the effort in labor and research, absolutely.

If you or your machinist/welder are competent, cutting and extending is a breeze. Once you gut the housings, use a pipe cutter to get a straight line and cut a section off the top, cut near the bottom of the housings and use previous cut portion to extend the bottoms. If space permits it, you could even get a spacer that goes below the strut that allows you to mount the bolt/nut on the housings even further down.

Here's a fun fact: if you can get custom housings for 8610's, you can go with Yellow Sport Eclipse rears, they're adjustable and fit S13 rears.

Apex Eight
08-23-2014, 10:19 PM
As much as I love Fortune Auto (I've owned three of their coilovers, I now only own one), they aren't close to my Yellow Sports and S-Techs. AND I don't even have a ton of travel.

I use my Fortunes for drifting and like other coilovers I've tried/owned, they get the job done but leave a lot to be desired once you've tried Koni and Bilstein.

If you just want something to put your car low and have adjustable rebound, go with Fortunes. But if you want to make the most of your suspension, Koni or Bilstein or Ohlin or Penske. Are Koni's/Bilstein's worth the effort in labor and research, absolutely.

If you or your machinist/welder are competent, cutting and extending is a breeze. Once you gut the housings, use a pipe cutter to get a straight line and cut a section off the top, cut near the bottom of the housings and use previous cut portion to extend the bottoms. If space permits it, you could even get a spacer that goes below the strut that allows you to mount the bolt/nut on the housings even further down.

Here's a fun fact: if you can get custom housings for 8610's, you can go with Yellow Sport Eclipse rears, they're adjustable and fit S13 rears.

Gotcha. Thanks for sharing your experience man, I really appreciate it.

I don't plan on drifiting, just autocross, and maybe some occasional track days but that is far far into the future. To save money, I might just do what you did and forgo the GC setup and just get some springs. Height-adjustability is not that big of a thing for me. I definitely do not plan on slamming my S13, I just want to reduce the gaping space between the fenders and tires.

What are some good spring choices to match with the yellows? I've read that progressive springs are to be avoided and that linear is the way to go.

Aside from the four Koni sports, a set of springs, and my stock housings, is there anything else I should look into to complete the setup and installation?

Moore
08-24-2014, 01:51 PM
Always more camber. Not drift-tard levels like 6*, but 3* will make it better.

More camber will allow you to drop pressure, too. You can read the edge of the tire and adjust pressures accordingly.

Also, square tire setup helps, and a bigger front bar.

Obviously tire compound is paramount for autox, so better tires will help immensely.

Thanks for the pointers. I'll add a couple degrees in before the next event. My tire's only have a max pressure, so I'm not sure how low I should take them. I had them at 30 all around.

A front sway bar is a good idea. The nose is really diving in the pictures that were taken. What would be a good size to go with. I found this thread which outlines sway bar options. I would guess you have to match it to your spring rate, so lower spring rates larger bar dia?

http://zilvia.net/f/showthread.php?t=108009

I have tein super streets - 6kg front & rear. stock front bar, hicas rear.

racepar1
08-24-2014, 02:35 PM
Thanks for the pointers. I'll add a couple degrees in before the next event. My tire's only have a max pressure, so I'm not sure how low I should take them. I had them at 30 all around.

A front sway bar is a good idea. The nose is really diving in the pictures that were taken. What would be a good size to go with. I found this thread which outlines sway bar options. I would guess you have to match it to your spring rate, so lower spring rates larger bar dia?

http://zilvia.net/f/showthread.php?t=108009

I have tein super streets - 6kg front & rear. stock front bar, hicas rear.

Stiffer front springs are in order, I would say start with 8k. You can drill another set of adjustment holes in the front sway bar to make it stiffer. I used to run the SE 25mm front sway bar with stiffer adjustment holes drilled about 3/4" in front of the stock endlink mounting points. As for your rear bar, GET RID OF IT. The HICAS 21mm rear bar is way too stiff. With that bar combined with your soft front springs I bet the car is VERY loose on the throttle. I used to run without a rear swaybar at all and the rear grip on the throttle was MUCH improved.

e1_griego
08-25-2014, 02:53 PM
With lowering springs I recommend upgraded front and rear bars (extra spring rate that you need).

With coilovers, it's driver preference. I run stock 15mm rear bar in my autocross car and the car works much better in steady state/constant radius cornering than it does without.

Moore
08-28-2014, 01:30 PM
I got 8kg springs on order, I am hoping they arrive before the 5th of September to try them out that sunday.

I'll stick with the bar's I have for now and see how the stiffer front springs work. I'm joining the league next year so I will have lot's of opportunity to disconnect the rear and also pick up a stock 15mm and try both out. Interesting idea removing it, I guess it makes sense for slow speed sharp corners. I'm use to that kind of thing for wheeling, never would have thought of that for performance after driving my truck down the highway with no bars.

racepar1
08-29-2014, 12:28 AM
I got 8kg springs on order, I am hoping they arrive before the 5th of September to try them out that sunday.

I'll stick with the bar's I have for now and see how the stiffer front springs work. I'm joining the league next year so I will have lot's of opportunity to disconnect the rear and also pick up a stock 15mm and try both out. Interesting idea removing it, I guess it makes sense for slow speed sharp corners. I'm use to that kind of thing for wheeling, never would have thought of that for performance after driving my truck down the highway with no bars.

It's common on indy car road course setups to run without rear sway bars. Most people don't really understand how a swaybar works. As the outside suspension is compressed the swaybar is lifting up on the inside suspension and removing weight from the inside tire. This causes uneven loading across the rear of the car and promotes oversteer. The bigger the bar, the more uneven the load is. On a tail happy car like the S13 "upgrading" the rear swaybar is just not necessary.

Dcocci
09-01-2014, 05:27 PM
First off, I hope the OP is doing well with his setup! As he probably has figured out, having a SR20 240 is a ton of fun to race, however it DOES put you in the street mod class with SCCA. Saying that, Unless you plan on running a gutted caged car with a good wheel/slick combo and built suspension, don't worry about what your working with setup wise because you more than likely wont comptete right away. Don't worry about koni's vs fortunes. Dont worry about what swaybars to use. As you gain experience, you will figure out what parts and setup you want and what your class will allow. Focus on improving times, and staying consistent. Replace parts as you go. Best of luck!

koukis13
08-11-2021, 11:36 PM
Thank you for this post