So I’m looking to add on to my suspension modifications a little bit before I start auto-x. I’ve already done Yonaka coilovers (not bad, but will look to upgrading in the future), Hyperflex kit from Energy with trailing arm bushings (this helped a ton!), and front and rear camber kits. About to redo my lower ball joints again (with OEM this time) along with another OEM tie rod (already replaced one). Definitely have taken care of the worn stuff before I bothered considering aftermarket. I’m stuck between two kits. One being the ST front and rear swaybar set, which I’ve seen a lot of positive feedback on. And the other being the ASR rear subframe and swaybar kit. I’m wondering which would be the best bang for my money? From what I understand, stiffening the rear without touching the front should result in more oversteer, which some people prefer. Personally I prefer it to be equal or a touch more biased to understeer (about how it feels now). After talking with a friend who used the ST kit on his Sentra SE-R he said it’s designed to give a touch more understeer than oversteer.
I’d love to hear from some people who have experience using either kit, or your suggestions for alternatives. I’m not looking to skimp out (done this before, moving away from it) but I’d like to keep it under or close to $400.
Also, my Yonaka’s are 12k front and 6k rear. I’m wondering if a 24mm rear sway bar would be too stiff for my rear spring rate. If anyone could explain how those two work together I would be forever in your debt!
I have the ST rear sway only (front is stock with upgraded bushings) and it feels very good. It creates a predictable amount of over steer. I did similar research before I bought mine and I opted out of the whole ST kit. My understanding is that the whole ST kit (F+R) would stiffen the feel of the car but not change the under/over steer balance too much compared to stock. The stock ratio was designed for the general public for safety reasons, hence the tiny rear sway bar. Being a front wheel drive car, IMO adding some over steer is a must for auto-x etc. You mentioned that you would prefer it to be equal…I would encourage you not be afraid to add some over steer.
The other option being the ASR bar, I don’t really like how it removed the stock design of the sway bar movement. I feel like OEM is always better. Also, a 24mm rear only is going to create a LOT of over steer for this car.
Strickly answering your sway bar question - I say go with the rear ST only or get the ST Front + ASR rear…your choice depending on your funds. For reference I am running 10k 8k GC + Koni. I think you should consider bumping up the rear to a 10k setup. If I was in your place I would buy the ST rear bar and put the rest of the money towards rear coils/springs with higher spring rates.
Honestly, I can’t tell much of a difference between all of these setups. Although there were always more changes done so it’s hard to make a good comparison. I feel the car is very neutral where it is now (combined with 700f/600r GC’s on Koni RACE shocks, toe at zero, -4.0/-2.5 camber, 205-50-15 ultra high performance summer tires) however the rear end will break loose. It’s hard to judge under/neutral/over because everyone’s personal preference is different.
I always feel the best option is to “step up” to a more aggressive setup - don’t build a beast and expect to be able to drive it as a novice. ASR is not a “bang for your buck” modification. I’d try to find an ST set or ST rear used and start with that - or a used Progress bar. If you’re doing autocross instead of track days then it might be wise to just start with the Progress. Oversteer can be more important for autox and less dangerous to deal with for a beginner than trying to have a twitchy car on a road course where speeds are much higher than autox.
With all of that said I already purchased an ASR brace kit + Eibach 25mm adjustable ITR rear sway bar and plan on running that in combination with my ST front bar. I likely wouldn’t have decided on this mod anytime soon other than the fact that the sway bar was free and I used some JHP gift cards to buy the ASR brace (big THANKS to JHP & Eibach for supporting the HFF Challenge!),
By “bang for my buck” I really meant it as which one is more worth the money. But I have a friend who can get me the ST front sway bar new for a good price, so I might do the ASR rear kit and the ST front
That should be a good combo. The reason I said the ASR isn’t a good bang for the buck is that if you’re building a car you have to prioritize what you buy and when. The ASR is a high end piece and worth what it costs. But IMO the benefits do not outweigh difference between the ST or Progress bars unless you’ve already been through those and have decided you need more rear bar. Most people (aka, anyone that does race, do track days, or autocross on a regular basis) that buy the ASR are buying it for it’s bling and will never utilize any benefits it may provide above and beyond the ST or Progress.
If you start with a fairly aggressive rear sway bar setup (ST front + ASR rear) then I would suggest more mild springs and alignment until you get used to it. If you’re legitimately interested in improving YOUR ability as a driver then you should be doing as little as possible to the car and instead focus on seat time.
Well my rear is 6k which is fairly mild, but my fronts are 12k. As of right now I’m running -2 deg front camber and -2.5 deg rear. I may switch that though. I figure with less neg camber in the rear it should be less likely to oversteer, and with more in the front it should let it understeer some, but give enough angle for when the front dives, the tires should be flat as well.
From a lot of spirited street driving, I’ve noticed I like a fairly neutral oversteer/understeer combination which is what I’ve accomplished right now as is.
The car isn’t bad right now, but one thing I am looking for is more steering response. I need to find my power steering bushings that came in the hyperflex kit and get that done too, which should help as well. Just ordered the new tie rod and ball joints last night so that as well should fix some of the slop I’m experiencing right now
That’s a really interesting setup, have you done any tuning to come to those specs? If not I’d definitely think about at least changing your camber - generally you want more negative camber in the front than in the rear as there’s a lot more weight up there and more of a need to combat rolling over onto your sidewalls. With a heavily front bias spring rate setup then I think you’ll be fine with an aggressive rear bar. If you were running 12k/10k then I think it might be a bit much to start with, but as you are now it’s probably OK.
Neutral to understeer is generally the smart way to go with a street car but when you start tuning for track use you may very well want a more aggressive setup. And at that point you just increase your ability to be able to drive a car that is more “on the edge”.
My friend who works at Nissan as a tech has autocrossed and tracked his Sentra SE-R a lot, and he said he generally ran more camber in the rear. Our two cars were generally the same idea (FWD light weight econo car) so I let him decide on what would be best. It works pretty well as is. I’ve never done any of the tests to see how far the tires are rolling over though. But I’m on some weird stuff right now. Trazano is the brand. Never heard of them in my life but they came with the wheels and they were almost new so I wasn’t going to bother buying anything else.
Oh yeah, I ordered the ASR rear kit and the ST front! Super excited to get them. I’m really hoping the 24mm rear sway clears my exhaust
LSD makes a HUGE difference. I’m using an OEM LSD and it’s been great so far but I keep hearing how much better the aftermarket ones are, specifically something like the OS Giken.
