Koni str-t Struts yes /no?

[dbeng]

I may need new struts soon on my 07 Mazda3S (not Mazdaspeed)
Currently it is completely stock and is my wife's daily driver so no plans to modify it for autocross.
But, if struts need to be replaced there is not much difference in price between OEM and Koni str-t (also known as Koni orange).
I would keep the original springs no plan to lower or stiffen the springs.

Would it be worth the little extra for the Koni str-t in terms of handling?

Would fitting Koni str-t change the classing out of the stock class?
Thanks,
Dan

[Jamie]

Not knowing anything about the stock shocks (in original form), it's difficult to say if there's a performance improvement -- probably a slight one. More importantly, Koni makes a good shock, so they'll do the job for a long time...for a DD, that's as important!

Bolt-in replacement shocks are "free" in everyone's rulesets. Some clubs will bump you into a different category if you swap to more complex non-OEM shocks; FAST doesn't care one way or the other.

[Loren]

Everything I've read about those particular shocks says that they're anything from "just okay" to "complete crap". For a pure DD, maybe... but, if you expect them to perform, I'd avoid them. Which is exactly what I did on my wife's car. I made her spring for Koni Sports instead. (and they're awesome)

If you just want cheap replacement shocks, I think KYB GR-2's are the way to go.

You might also consider sniffing around for a "take-off" Mazdaspeed 3 suspension. Somewhere, someone who doesn't know any better has bought one, pulled off the "decent" Mazdaspeed suspension and put a coilover kit on their brand new 3S so that they could slam it and stance it, yo. Pick up a full set of proper low-mileage MS springs and shocks (don't forget the swaybars) for cheap and you're good to go.

[Jamie]

Everything I've read about those particular shocks says that they're anything from "just okay" to "complete crap".

From what I've seen, many of the reviews are written by people expecting Koni Sport performance at a discount. TANSTAAFL. Can't argue with GR-2's...had those on the minivan and later on Jill's Element, and they worked well.

[dbeng]

Thanks for the feedback guys,

So now I'm torn between replacing all four shocks with KYB for under $300 or go for around $350 best price I can find for Koni sport front struts only. I could replace the rears at some time in the future. I'm planning on keeping the car for a few years as a daily driver and part time autocrosser in stock class.
Actually, thinking about it, the adjustable shocks may be ideal as I can soften them up between events and dial the stiffness up for autocross.

Do you think there would there be any problem running koni sport up front & original stock rear shocks in the meantime?

Trying to weigh up the options soon so I can order and get whatever I end up with in time to fit over Thanksgiving weekend.

Thanks again,
Dan

[Loren]

If you're going to keep it, and especially if you're going to autocross it at all, the Sports are a worthy investment.

Jamie is right, though. The STR-T shocks are probably "acceptable" as a stock replacement. It's all about expectations. (the negative reviews were on a Miata forum where expectations are high)

[Jamie]

Do you think there would there be any problem running koni sport up front & original stock rear shocks in the meantime?

It depends on how worn the stock shocks are. As a DD, you can probably live with it for a bit. As an autocross car, the handling could be interesting. Depends.

[dbeng]

Guy's you're killing me

I'm already getting sucked in to the famous upgraditis. What started as an innocently rotating my tires yesterday after hammering the fronts pretty hard at the novice school, led to noticing an oil leak in a strut to researching replacement struts to finding performance options to seriously considering Koni sports all round

If I go with the str.t option I will always wonder what if? Not to mention being out of pocket the cost of them if I decide to upgrade to sports in future. Of course using the old "while the hood's up" philosophy I can't see putting top of the line struts on with the old mounts and bearings so those will need to be replaced at the same time. Aaaaggggh!

I've got a few e-mails & PMs out to some of the sponsors on the Mazda3 forums to see if there are any deals available. Let's see what happens.

Seriously though, thanks for your comments it helps a lot.
Dan

[twistedwankel]

Are your current shocks leaking oil (there is supposed to be some oil on the polished shaft to keep it healthy)? Bottoming out? Bump stops gone? Tires and alignment are king.

Your wife driving this car may not like a harsher ride on a daily basis. (Ask me how I know that.)

I can tell you this: When I put koni yellows on my 90 Talon and put the rear shocks full hard (undrivable due to kidney damage on street/hwy) the car was instantly 2-3 seconds faster on R tires (than my competitors) and rotated perfectly with fronts set about 3/4 hard and stock bars. I invented a slotted rod for the rears so I could collapse the shock rod and adjust it back to softer for normal use while still on the car. My daughter drove that car for +140k before finally breaking a front one and denting the hood (shaft launch).

Koni's only work in rebound meaning you might have to change your bar(s) to limit initial roll with stock springs. They sometimes push your car up 1/2" which you may not want?

GR-2's are pretty good for low buck as mentioned. Used them on my last two xcross Mustangs. Tokico used to be good? AGX are adjustable 0-10 with a dial on the side and I mixed them with Red Koni's (discontinued now) on my Mustang successfully.

If you can afford them Bilsteins are pretty awesome and you don't have to worry about adjusting them ever. Believe they have a lifetime guarantee to the original owner like Koni. I put them on the rear of my Crown Vic and it really handles/rides well now for several years.

ALL that said I have Koni yellows on my RX8 which are excellent with rears set permanently at 55% hard and stock bars.
Eventually I'll be buying Bilstein "performance" for my C5 with Z51 pkg from Tirerack with free delivery and no tax as they come most recommended and only cost $400/set which is awesome in today's pricing.

Doug

[Loren]

Your wife driving this car may not like a harsher ride on a daily basis. (Ask me how I know that.)

I cheated my way around this one. When I put the Koni's on my wife's car, I set them at 1 turn from soft (out of 2 turns, so about half-way) and the car felt AWESOME! Of course, my wife hated it. It wasn't even ride quality, she didn't like the added steering heft. So, I made her live with it for a week, then I turned them down to 1/2 turn... no complaints.

Konis near the low end of their adjustment really don't ride harsh at all.

[twistedwankel]

Konis near the low end of their adjustment really don't ride harsh at all.

Totally agree with him!!

[Loren]

I guess I should be clear. The point of that exercise was that if I'd just put the shocks on full soft and she hated it (which she would, because she is largely resistant to any "change" in the way her car feels), I couldn't have "improved" it for her and she'd have been grumpy about it. Giving her a taste of "stiffer" that I knew she wouldn't like then gave me room to adjust them "softer" and improve things in her perception. After the first 1/2 turn adjustment, I still had MORE that I could give her if she still hated it.

(yeah, I've been married for 20 years, I know how to play this game)

[dbeng]

So I bit the bullet and ordered Koni yellows all round. I couldn't stretch to Bilsteins - especially since this whole idea was unplanned and developed due to a leaky strut
I've seen nothing but good reviews on the yellows so at least I won't have to second guess myself as I'm sure I would if I went for anything less. Go big or go home....

Plus I do like the idea of softening them up for day to day use. I'm sure my wife will appreciate it! I will have to find a happy medium for the rears though as I don't feel like taking the wheels and shocks off every five minutes.

Does anyone know if the stock bump stops carry over to the Koni struts? I assume they do. This will be a fun project for me over the Thanksgiving weekend.
Dan.

[Loren]

Your bump stops should work as long as they are intact. Mazda used some weird rubber compounds for some of their bump stops. If you have a 99-05 Miata that's more than about 8 years old, for instance, the rear bump stops will have turned to a crumbly red powder by now!

I think for a DD that your wife will drive, Konis are better than Bilsteins. I love, love, love a good set of Bilstein shocks, but the very thing that makes them great is the same thing that makes them suck. They are valved to give fantastic steering response... and the side effect is that they transmit small bumps directly through the car. Larger bumps they'll suck up just fine, but stuff like washboard roads, brick streets and such they will rattle your teeth!

For FWD on stock springs, set the rear shocks as stiff as you can stand and leave them there. That will help eliminate some understeer. The fronts you'll run at or near full soft.

[Jeremy]

For FWD on stock springs, set the rear shocks as stiff as you can stand and leave them there. That will help eliminate some understeer. The fronts you'll run at or near full soft.

So he could have just bought str.t's and a rear sway bar?

[Loren]

If the STR-T's weren't crap, sure.

And if he's going to seriously autocross the car, he should add a rear swaybar, anyway. But, that's a question he didn't ask.

[twistedwankel]

Koni dyno's the rear shocks at the factory. Which means they are perfectly matched as pairs. Check with them to see where they set them if you can? Probably about 125% stiffer than stock. Or just mark and count turns back to zero. I painted a mark on zero soft so it would be accurate from zero to my 1.5 turns for RWD car. Many people driving the same car swear full hard is fine....right!!

The ONLY way to know the full sweep of your rear shocks is to do them full soft collapsed (holding down with pythons) and count the turns to full stiff (mine are 2 5/8 turns lock to lock = varies for each matched set up to 3.5). NOTE that the directional turn of my rears stiff/soft is reversed from the fronts!!! They include a diagram for both which might confuse you at first? You can easily live with 3/4 (75%) stiff in the rears. NO MORE for normal use when new at least.

Be prepared to be amazed.

My 2 cents.

Doug

[twistedwankel]

Does anyone know if the stock bump stops carry over to the Koni struts? I assume they do. This will be a fun project for me over the Thanksgiving weekend.
Dan.

Order yourself a new set of factory bump stops. Especially for the rears. Check the wear (holes in bellows) on the front dust covers too. Replace if worn. There is a rubber damper on the top of most springs that normally is okay. I replaced mine in the rear after 75k when I replaced the springs but the originals were still serviceable.

[Jamie]

I've seen nothing but good reviews on the yellows so at least I won't have to second guess myself....

You'll be happy with them, and the good news is they last for a long time. Know that since the shaft is thicker than the stock shock, you'll have to drill out the bump stops...a good enough reason to get another set.

[dbeng]

Order yourself a new set of factory bump stops. Especially for the rears.

Doug, thanks for the feedback, I was already planning on ordering new bump stops - I just didn't want to spend the money on a pair & find out they aren't used with the Konis which is why I thought I'd better ask. I will replace the top bushings (bearings) too as I would hate to have to tear everything off again & re-do the whole project if one craps out after installing the new struts.
I noticed the rear bump stops were completely perished when I rotated the tires last weekend so those went on the shopping list too. Turns out these were not sold separately by Mazda, only as part of the shock absorber but I found a KYB strut boot that comes with the bump stop.

All that's left is to try to find a relatively un-mangled pair of loaner spring compressors from the autoparts store over the next week and I will have everything I need for installation.

Why do I get excited about this stuff? I don't know it's always good to find an excuse to spend a day fettling on the old jalopy! Followed by a celebratory or two!
Dan