DefSport

I recently purchased an AP1 (2003) to make into my street/track car. The 100% OEM suspension at 144k mi is pretty toast, with the driver's front shock looking like it leaked its oil out quite some time ago and clunking badly. A little background about me, I currently have an S13 240SX track car that's HIGHLY modified and really a 100% track car. It's very fast (EFR 7163 twin scroll on a built SR20 block with SR20VE head, 500+ rwhp is possible on E85, Koni 8611 dual adjustables, Cusco RS diff, full aero, all rod ends/sphericals on suspension, custom brakes I made, Tilton twin disk clutch etc.). It's very fast on track, but not enjoyable to drive on the street. I've been driving on the track for 15 yrs, but I'm over the phase of making a car suck on the street to go half a second faster on the track. I just want something that will go out there and feel "good" on probably sticky street tires, maybe NT01s in the future in the usual 255/40R17 sizing.

The goal for replacing the suspension is to get something that's reasonable/comfortable for the street, but won't be completely out of place on track. Think more like an OEM Type R suspension turned up a little bit, but no 16kg/mm spring rates etc. The other goal is to keep it in the budget friendly range of sub $1k street pricing, as I don't really want lots of knobs to twiddle, or Ohlins (I know they're good, just not interested). Adjustable damping is a minor plus, but honestly, it's not big to me as long as the base damping is good for the spring rates. I do not want any sort of "cheap Taiwanese coilover" damping curve like a Megan Racing, BC etc. A stock suspension is probably faster than those....

So any real world experience with these two options? The Teins have top hats, and are even cheaper than the ST's, but the spring rates a bit higher and I'm not sure how they would ride on the street.

I'm more leaning towards the ST X's, as I've thought KW gets the damping pretty good out of the box (not perfect, but pretty good), and I've ridden in some Tein cars that have been good, and some that have felt horrible. Maybe going too far with adjusters, maybe the damper quality/valving? I can't find many Tein Flex Z reviews, so it's hard to really gauge the quality.

B serious

My experience with the ST (on another car) is that they're fairly agressive for what they are. The Flex Z will require some setup to get it to ride correctly...which is the case with any full body coilover since they have such limited travel inherantly.

I think you can probably make the Flexes ride better. I *think* the Z line is now moved from Japan to China, but I could be wrong...and it may not really matter.

Have you looked at Bilstein PSS or PSS9?

DefSport

Thanks for the reply. Honestly, the PSS/B14s look a little too soft for what I want. While I want to make it street comfortable, I'll still be running at HPDE instructor pace. The near stock spring rates just seem low since it seems like even my stock 03 stuff meets the bumpstops on occasion.

pretty sure the Tein Flex Zs are still made in Japan.

Stupid question, how do you adjust the rear shocks with the interior still in? Possible?

Bruunz

If the knob is on top of the strut then you can't. You will need to remove some interior panels from the boot.
I can't remember if you only need to take out the one larger on (that covers the spare tyre) or if the sides have to come off as well.

B serious

Its not uncommon to hit the bumpstops. The Flex Z will be on the stops more than the stock suspension...unless you address it by measuring travel first and then setting preload to keep it away from the stops.

The stock rear shock has like...7/8" of free travel, for reference.

Ther are also lots of fast cars using Bilsteins.

I like Tein. But...I'm not sure how well the Flex works for your uses. They might, though.

How come you don't want the Öhlins? Just cost?

DefSport

Just got back from the first track outing with the AP1. The car definitely feels very different out on track vs. on the street. On street it feels firmly sprung with pretty good control over the car (as good as 145k mi dead stock dampers can at least), but on track the car was definitely flopping over onto the bumpstops in every corner even with some horrid 500 treadwear all seasons.

Regarding the Ohlins - I know they're the "easy button" for something that works well given how many guys like them here, but it's just more than I want to spend. This car is a step back from the arms-race of spending more money to go faster. Yea, you can do that until the cows come home, and at the end of the day, blasting around TWS in the low 1:50s and chewing up pricey consumables really isn't that much more fun than the mid-low 2:00s. Been there, done that, I just want something that will feel reasonable on the street but not feel totally out of place on track with a set of sticky street tires. If something was substantially better at say, $1200 vs. $900, sure, I'll pony up the $300, but above $2k and it's just not worth it to me. I'll toss some CR springs on Konis before I do that.

I was honestly hoping the stock suspension would feel a bit better than it did, but the lack of bump travel and soft-ish rates seemed like they were all over the place. It really seemed like the rear had limited travel, as a few corners had the car change from immediate neutral/light understeer to a big shove of oversteer as the suspension flopped over. At least it felt to me like bumpstops, not so much bumpsteer (which was there, but didn't feel that obtrusive honestly, at least compared to the bumpstop WHACK of oversteer).



So maybe I should be concentrating on rear damper travel between these two offerings more than spring rates and whatnot? Just letting the suspension do its thing vs. slamming the bumpstops in normal cornering will always be faster on track.

I probably won't lower the car much, maybe 1/2-3/4", just to keep as much suspension travel as possible.


I could maybe run some extenders for the rear shock adjustment, but I want to keep all the interior in the car, as that's the whole dual purpose nature.

Also on the Ohlins thing, all the brands being discussed besides them I get wholesale pricing on... so it's really tough to pay street pricing on something unless it's THAT much better.

B serious

For all your purposes, I'd really still heavily consider a B16/B14 Bilstein kit. B14's if you plan on a re-valve/respring later. I know they're soft...but they're good.

Or Konis with GC's.

Or maybe Tein Monosports rather than the Flex Z.

The Flex Z just seems like a very soft, street setup. I realise the Bilsteins are sprung more softly...but they feel so solid compared to Tein setups I've experienced.

The advantage of the Öhlins is a blend of comfort and trackability...but, IMO, the most important part of the Öhlins setup is the feel. If you're only lowering 1/2", you can definitely set the Öhlins (or any full body coilover) with enough rear preload to help the travel situation...or use springs stiff enough to resolve it, while still maintaining ride quality.

I came from an over the top (not as over the top as yours) SR20 swapped S13 that I started putting together in 2002 lol. I have used my S2000 as a track/street blend car since 2006. So I am in the same mindset as you for my S2000. In the sub $2000 price range, I really think the Öhlins are just about the most advantageous overall system for a "trackable street car" setup. The next best thing I've tried is the out-the-box Bilstein PSS9.

Bruunz

I can vouch for the PSS9 - I have had them for 2 years and they are great. I run them on the softest while DDing and then stiffest whilst on the track.
Only after 2 years of the track i am starting to think that they may be limiting me (i run squared 255s AD08Rs on a pretty much stock AP1).

DD aspect, they are great. I bought my car on koni yellows with lowered springs and honestly was let down by how the car handled verses my expectation. I wanted new stock suspension but they were going to cost more than the PSS9s. I've been extremely happy with my purchase.

You would only need to access the rear adjusters if you were at the track. Just remove the panels the night before (because racecar) and put them back when you return. I don't see a need to not be on full soft while DDing.

DefSport

I've ridden in one E36 M3 long ago with PSS9's. They felt ok, but it did seem pretty softly sprung at the time, but it's been many years.

Have you ridden in a car with KW V1s? That's basically what the ST X coilovers are, and usually KW gets it pretty good as long as you're up in the high end of the height range, which I most likely would be.


Honestly, while my car has blown factory dampers, it did feel like it needed more spring rate all over the place over stock. That's why the PSS's worry me. I've seen some dynos with the PSS9 rebound adjuster in action - doesn't look like it's worth the ~$350ish more they command.

I don't mind piecing together a Koni/GC setup, but I've been a little miffed with the lack of travel a stock length shock usually yields in the past. I have Koni 8611's in custom housings on my S13 right now and built the setup one piece at a time (and actually had a few pieces made for that purpose over the years). I could probably put together some used GC bits with new Konis for about the same price as the ST X coilovers, but I've got to question if the ST X dampers are really that bad? I know Koni Yellows are pretty decent, but you're usually using the middle 1 turn of adjustment range to set the shock up, then never touch it again. Seems hard to believe the ST X dampers would be that far off a Yellow...


I'll read up some more on regular PSS's, but I wonder if they can take another 100 lb/in of spring rate out of the box and still feel alright. I just worry the car will be flopping over on the bumpstops with them.

B serious

ST-X's aren't inherently bad. They're actually quite good. I had some on a TSX. Yes...I agree they do well at fairly tall heights.

I'd rather have something with a damping adjuster that works well. KW sets stuff pretty good...but they set it to a compromise, depending on their understanding of use... as with any non adjustable shock. Not a bad thing. I'd just rather have some adjustability.

And I also agree that Konis will not have an advantage in travel as compared to stock. Maybe even a small disadvantage because they don't have an external reservoir.

Have you looked at Monosports? I think they're priced at like $1500 retail.