Mazda3 Forums banner

81 - 100 of 130 Posts

·
Registered
Joined
·
464 Posts
I have a little mental checklist I run through before each run. I've definitely forgotten to check everything a few times, but this is my list:


radio off
air off/recir on
esc off
gopro start recording
tighten seatbelt


Did you also increase your rear spring rate when you put the fronts up to 550 lbs?
 

·
Registered
Joined
·
406 Posts
Discussion Starter #82
No, I was delusional and didn't think I needed to go up in rear spring rate. I had always had a stiff front since I started. Stock springs with huge Hotchkis front bar. Then, MS coilovers with Hotchkis bar. Then, stock front bar, 550lb springs, and camber plates. I was trying to keep the relative front stiffness the same. To me, softer wasn't faster. Well, I'm a believer now. I put the MS coilover springs back in (400lb) with the stock FSB and camber plates. This is the softest front end I've ever driven and it is amazing the transformation. Spoiler alert: I finished 1st in PAX this past weekend!

The only time the rear has changed is when I went from stock springs to the MS coilover kit. It has always been a bit loose...in different ways as I've chronicled in this thread. For the next event I am putting the 550lb springs on the back. I also ordered a set of 350lb springs to try out on the front (I hope they get to me before the next event).
 

·
Registered
Joined
·
486 Posts
MS Coilover Kit?

......... Then, MS coilovers with Hotchkis bar. Then.......... Well, I'm a believer now. I put the MS coilover springs back in (400lb) with the stock FSB and camber plates........

The only time the rear has changed is when I went from stock springs to the MS coilover kit......... For the next event I am putting the 550lb springs on the back. I also ordered a set of 350lb springs to try out on the front (I hope they get to me before the next event).
"MS Coil-over Kit". Is that a Mazdaspeed Coil Over kit? I can't find one in the Mazdaspeed catalog online.

If so, where can someone find them? Do they relocate the rear springs from stock location to a true coil-over design?

What camber plates are you using?

Thx.......
 

·
Registered
Joined
·
407 Posts
What is your setup now? Stiff front bar has always been a bad idea on this chassis. The fastest 3's I know are all on the 2.0 sway bar or even no front sway.

I'm also curious as to your reasoning behind the rear spring being so stiff; it may work mid-corner, but stiff springs will also plant the rear down immediately when you hit the gas, taking more load off the front wheels.
 

·
Registered
Joined
·
14,002 Posts
I guess a better question would be to look again at what RSB you have? Those are indeed pretty stiff rear springs though.

Stiff FSB in a FWD is good ... with one circumstance. To make it actually worth it you have to have a not open differential. With that said you should really look at spending less money and go ahead and get a secondary trans and put in a differential as it will make a massive difference.
 

·
Registered
Joined
·
406 Posts
Discussion Starter #86
"MS Coil-over Kit". Is that a Mazdaspeed Coil Over kit? I can't find one in the Mazdaspeed catalog online.
If so, where can someone find them? Do they relocate the rear springs from stock location to a true coil-over design?
Yes, the kit is from the MS Accessories catalog, part number RAMS-8M-L10...click here. You can order them at any Mazda dealership or sign up for sponsorship from MazdaMotorsports and order them online with a hefty discount.

No, they do not relocate the springs. I would imagine that would not be legal for most classes of racing...autocross, road racing, rally, etc.

What camber plates are you using?
Corksports...i did a whole detailed post on them in post #57.

What is your setup now? Stiff front bar has always been a bad idea on this chassis. The fastest 3's I know are all on the 2.0 sway bar or even no front sway.
Front: MS shocks (as from the box...non rebuilds), MS 400lb springs, OEM 2.3 Mazda3 sway bar, Corksport camber plates ~2.5*. I am switching to the 350lb springs as soon as they come in.
Rear: MS shocks (non rebuilds), MS progressive springs, Hotchkis sway bar, SPC camber arms ~1.5*. I am switching to 550lb linear springs, TriPoint custom perches, and Megan Racing toe links before this weekend.

I'm also curious as to your reasoning behind the rear spring being so stiff; it may work mid-corner, but stiff springs will also plant the rear down immediately when you hit the gas, taking more load off the front wheels.
Most of my experience has been doing things by my own reasoning and so far I've been wrong most of the time. So I'm going to answer by saying, because much smarter racer said I should and because the calculations say so. The way I understand it is you want to able to rotate before the apex and then "catch" or plant the rear with the throttle at the apex.

Also, the rear spring has to be "so" stiff because of the motion ratio. With the spring mounted inboard on our cars the MR is 0.71. MR is squared in the spring rate equation, so 0.71 squared is 0.5. Meaning a 550lb spring's effective rate is only 275lb at the wheel.
 

·
Registered
Joined
·
486 Posts
Thanks for the spring info. I am a Mazdaspeed member, still could not find the coilovers within their site. Will just call them today.

Where do you find, and who makes different rate REAR (linear) springs for our cars? Would love to find those.

Thanks again.
 

·
Registered
Joined
·
406 Posts
Discussion Starter #88
No problem. Search by the part number above and that should get you what you need.

The springs are the easy part, Hypercoil, Eibach, and Swift. The perches to hold those springs is the hard part. I just happen to get lucky on a custom set of perches. I've heard BC makes a 2.5" ID perch, but you may only be able to get them by purchasing an entire coilover kit. I've also heard Ground Control has a perch now. I've seen where a guy with a MS3 used a block of delrin and AST perches from another chassis (see pic below). Unfortunately, I'm not sure of an off-the-shelf kit available for our cars.

 

·
Registered
Joined
·
486 Posts
Guess what I found.... and ordered.



Just out (this week!!) from Ground Control, a MS3/MZ3 coil-over kit that fits Konis. They should arrive Tuesday. Around $440 shipped with your choice of spring rates. You should already have your Konis. OTS Konis are good for around 600# springs or so I'm told.

When you call, ask for Donovan, tell 'em Scott sent you. ;-)

These should answer all of my suspension concerns, especially the rears.

Thanks for the idea, you sent me in the right direction.
 

·
Registered
Joined
·
407 Posts
Son
Of
A
Gun

Why weren't these released ten years ago! I'd much rather rock this setup with dyno-matched Konis than my BC kit. How do they interface to a camber plate? Is GC also making a Mazda3 camber plate? :shocked:
 

·
Registered
Joined
·
406 Posts
Discussion Starter #92
Guess what I found.... and ordered.



Just out (this week!!) from Ground Control, a MS3/MZ3 coil-over kit that fits Konis. They should arrive Tuesday. Around $440 shipped with your choice of spring rates. You should already have your Konis. OTS Konis are good for around 600# springs or so I'm told.

When you call, ask for Donovan, tell 'em Scott sent you. ;-)

These should answer all of my suspension concerns, especially the rears.

Thanks for the idea, you sent me in the right direction.
No problem Scott. Always glad to help. Can you post up the part number?

BTW while we're on the subject, I got my custom TriPoint perches installed last night. I will be doing a post on them soon.
 

·
Registered
Joined
·
486 Posts
Here is their part # off my invoice....... 4039.02

Not sure if it matches their future posted part number or not. I've emailed and spoken to Donovan there as my contact, he seems to have all the details on this brand new item. He also made recommendations for starting spring rates for my car and setup (525f/650r). He called it an "aggressive autox" setup.

These are so far listed under "2010+ Speed3" BTW. That may change if enough of us buy them for our first gen cars. :lol:

Camber plates are *almost* ready, still in final testing stages I'm told. Soon. I'm on their list.

No problem Scott. Always glad to help. Can you post up the part number?
 

·
Registered
Joined
·
406 Posts
Discussion Starter #94
Go back and read my post (#80 in this thread) on selecting spring rates. 525f might work better for a Speed3 with the extra nose weight, but I think that's going to be a lot more than you want. I used to run 550f on my car and it wasn't ideal. The 650r spring is a super aggressive setup, but does fall in the range for a regular 3.

I am trying out my 550 springs on the rear tomorrow and I'm going down to 350 (from 400 now) on the front soon.

Glad to hear about the camber plates. I hope one can use them without cutting the shock tower considering that isn't legal in STF.
 

·
Registered
Joined
·
486 Posts
Yep, I actually did a "copy/print" of the data in your posting on spring rates. It's in my notebook. I shared with Donovan my car info (3i, 2650#, big rear bar) and asked him based upon their testing data what he thought would work. That was what he came back with after checking with his "people".

What's really cool about their MZ3 setup is that both front and rear springs are the same 2.5x6.0 springs!!! Yep, interchangeable. Cool, huh? So if this is too much for me, I could move the fronts to the rear, and buy some softer fronts.

Yes, the camber plates (I'm told) will allow for the smaller shock tower holes without cutting. He said something about the design being a little different somehow, not like typical camber plates. At this time they are projected to sell for around $150.......

I'll share pics when mine arrive.

I want to thank EVERYONE in this Forum for being so willing to share data, info, experiences and more in helping us all make progress with our cars. Without this great databank of info, the journey would be much slower and definitely more expensive. You are a great group of guys.
 

·
Registered
Joined
·
32 Posts
Oh man that's awesome! I've been looking for something for my future 3 road race car that was not a full coilover as they are illegal.
 

·
Registered
Joined
·
406 Posts
Discussion Starter #97 (Edited)
SCR SCCA - Black Lake - Oct. 27, 2013

Wow what a day! The front spring change made a HUGE difference. I think the results will speak for how well the softer springs worked.

Weather-
Cold morning, but warmed up to 70 for my runs. Not a cloud in the sky. Perfect day for autocrossing.

Setup-
Ran on all the Mazdaspeed supplied springs, 400 front and 290 progressive rear (will put my 550 springs in rear). As I’ve noted before with these springs, it causes the nose to rise about ½ an inch. Shocks still at full soft up front and nearly full stiff in rear. Pressures at 38-39 front and 40 rear. Still on stock ecu tune for now and 87 fuel (got my first “base” file from Dynotronics). Camber and toe were the same (just purchased rear toe links).

This is the softest setup I’ve ever run on the front end. It is amazing the difference. The front just digs in and almost takes itself to the apex. Add in a touch of rear slide and it is a glorious feeling. This is by far the best the car has ever been. Honestly, I don’t particularly like the way it feels with the body roll. It just doesn’t feel fast to me, but by the stopwatch it is undeniably faster…by a lot. I can already tell that it’s going to take some time for me to get used to this setup as it feels a little uncomfortable for me. We’ll see if adding the rear springs change my mind.

Another thing I was going to try out at this event was going back to 1 foot driving instead of 2 footing like I’ve done for 2 years now. I think this was a huge improvement in my performance at this event. Only once can I remember hitting the ABS limit, and I didn’t even come close to the brake assist limit. I felt a lot more precise and accurate when using the brakes with my right foot. I don’t think I’ll ever go back to 2 foot again.

Course-
It had one of the slowest starts I’ve ever seen as I was in first gear for quite a while. It also had 4 other tight elements that would present a good test for the new car setup. The course was challenging as it was difficult to get the right line while also keeping the right speed. See video below.

Video-
Fastest run – 59.362, 1st in Pro class, 1st overall

Results-
1/29 in PRO....Class Results
1/112 in PAX (1000!!) ....Pax Results
I know it’s just a regional event, but it is a huge confidence booster. And it is great to get my first career overall win in my home state and at my favorite venue.

Looking forward to another race at ZMax. See if I can improve upon the NCAC event there last month.
 

·
Registered
Joined
·
406 Posts
Discussion Starter #98 (Edited)
Long nights in the garage…

Finally got around to installing my Tri-Point custom rear spring perches and height adjusters. These parts are holding 60mm x 6" long 550 lb/in Hypercoil linear rate springs. The height adjusters were mounted by running the subframe bolt through the threaded tube's base. The collar is held in place by a hex set screw. The bottom perch simply sits inside the center hole of the lower control arm with no hardware attachment. The perches were slightly smaller than the center hole. So to prevent any chatter noise and to fill the gaps, I put Gorilla tape on the mating surfaces. Once I put the spring in, I used a zip tie to keep everything from falling/jumping out of place...not necessary but just made me feel better. Isolators were supplied to prevent chatter between the spring and perch.

Check out the new hardware next to MS Acc. hardware...wow!
For legality purposes, these adjusters and perches are legal under rule 14.8.A.

UPDATE: DO NOT INSTALL NON-OEM TOE LINKS OF ANY KIND FOR SCCA "STREET TOURING" CLASS COMPETITION AS THEY ARE ILLEGAL!!!! Ignore pretty much everything I said below, unless you want to install aftermarket adjustable toe links for another purpose.

Next, I installed the Megan Racing adjustable rear toe links. It has been determined that when the rear suspension travels, the toe inward increases drastically. I want to eliminate or at least minimize that effect as much as possible. That's where these links come in. From a fellow racer, it was suggested to first pull the LCAs inward as much as possible by turning the eccentric bolts where the LCA connects to the subframe (see 2nd pic below). This does 2 things, it narrows the rear track width by 1/2 - 1 inch (really convenient for us cone dodgers!) and it changes the dynamic geometry of the trailing arm as the suspension travels. The rear of the trailing arm will now be traveling more upward instead of upward and outward. Of course, this only works when installing adjustable length links because, as you can see from the pic below, the OEM link is fixed. This also only works with adjustable camber arms, as the OEM arms are fixed as well. Adjusting my SPC camber arms to add back the negative tilt I lost moving the other links/arms was all that was left. I later determined that when the lower control arms are pulled all the way in and the toe links are set to 0 toe, that the length of the camber arm returns nearly identical to the length of the OEM arm at 1-1.5* rear camber. Interesting observation I thought. My spoiled plan was to exploit rule 14.8.H by reinstalling the OEM camber arms and use the toe links as my one adjustable link to "correct" the camber...would've been a brilliant secret for a while!

Here’s the Megan Racing links next to the stock stamped steel link.
For legality purposes, these toe links are legal under rules 14.8.H.3 and 14.8.H.4. My SPC camber arms are also legal under these same rules. Lastly, turning the eccentric bolts to pull the LCA inward is legal by rule 13.8.B. All bushings are legal under rule 15.8.C. Nope not true, the toe links are illegal for SCCA Solo "Street Touring" category and I have since replaced the Megans with OEM parts!

After clarification from the SEB (see below April 2014 Fastrack) 14.8.H does not allow for multiple adjustable links and does not allow for non-OEM toe links at all.
Member Advisories
Street Touring
#13236 Toe Link Clarification
There is no allowance in Street Touring for aftermarket toe links. In regards to aftermarket control arms, you can replace your upper or lower arm. However the mounting points must be in precisely the stock locations, excluding the sway bar endlink mount, and excluding incidental changes in length due to camber adjustment. Additionally the bushings must meet all the requirements of 15.8.C.
Here's the eccentric bolts in their full "pulled in" position. This makes the LCA as short as possible. (short being distance from the centerline, the arms can't actually get physically shorter..duh)
Installation comments:
1) The first thing I did was I measured for ride height before disassembling anything, so I knew exactly where to put the collars.
2) I disconnected the rear sway bar. I did not reconnect the sway bar until the car was resting on it's own tires and under it's own weight. Connecting it at full suspension droop can introduce binding and preloading.
3) I made sure a jack was used under the control arm when disconnecting LCA from the trailing arm. I also used the jack when reinstalling LCA bolt. And, I used a screwdriver to help line up bushings to reinstall bolts...this will save a lot of heartache!
4) Before installing the toe links, I made sure they were the same length relative to each other. That way both sides would be equal length from vehicle centerline when installed.
5) I left the jam nuts on the toe links loose until the car was under its own weight. Again, to prevent binding and have the two ends line up naturally.
6) The bolt attaching the toe link to the subframe on the passenger's side is long and the gas tank makes it very hard to remove. I suggest cutting the excess bolt off (~1") to make it easier to remove and reinstall.
7) Before trying to adjust my camber arms, I unbolted the shock to give myself some more room.
8) I think every bolt in the rear suspension (including the subframe bolt) had a 17mm head. I torqued them all to 75 ft-lbs with my torque wrench.
9) Lastly with the car on ramps, I measured the toe with a tape to get it as close to 0 as I could...erring on the side of toe in. Then I tightened the jam nuts down and reattached the sway bar. I'm going to let the suspension settle for a week or so and then get a computer alignment.

Here's the results after install…

 

·
Registered
Joined
·
406 Posts
Discussion Starter #100 (Edited)
CCR SCCA Autox #10 - ZMax Dragway - Nov. 2, 2013

Back to the great sealant expanses of ZMax Dragway for the final round of the 2013 Central Carolinas Region solo season.

Weather-
Cold morning, but warmed up to 65ish for my runs. Another perfect day for autocrossing.

Setup-
Ran the new rear Hypercoil 550lb springs on TriPoint adjusters. I started the shocks at full soft up front and nearly full stiff in rear. After the first crazy loose run, I turned the rebound down to halfway and bump down to about ¾ stiff. That seemed to calm it down a little. Maintained the tire pressures at the usual 38-39 front and 40 rear. Again on stock ecu tune but 93 fuel (have yet to load my file from Dynotronics). Front camber was the same, but the rear camber was around -2.2* after toe link install which was way too much. Ran my normal toe out up front and tried my best to adjust the rear links to give me 0 toe out back.

Course-
Another great course by our designer. Offset heavy as usual. I loved the bus stop right after the turn around at the top of the lot. Most of the course really made you concentrate on what was next and not so much trying to get through every element as fast as possible. There were several places where you had to give up a little to set yourself up for the next element...good characteristic of a great course if you ask me. If you didn’t chain your run together and just attacked every element, you were not going to have a pleasant ride or a decent time.

Like I said above the rear was crazy loose on the first run. Combination of cold RS3s and the new rear setup. I lost the rear and spun on the first transition at speed. I found the limit pretty quick! Most of that run felt really uncomfortable. Backed the rebound down for run 2, and didn’t push quite as hard. A little better, but still not instilling confidence. I decided what the heck, and started pushing it again. The car responded much better, but it still needed some work on the setup. I gained almost a whole second on run 3 though, my fastest. Run 4 was within a tenth of run 3.

Overall the car didn’t feel “comfy” to me. I again wasn’t able to drive 10 tenths, and just generally couldn’t anticipate the car. The rear was sticking when I thought it would slide and the front was getting too much understeer. It was probably my crappy driving and the rear camber and a bad shock setup and the crappy pavement sealer. But even with all that, the car was a cone and a tenth from top pax. I know progress will be made with the new springs and links once I can get it honed in.

I promise I tried to get my GoPro mounted to show the rear suspension, but I couldn't get the suction to stick where I needed it for some reason...probably because my car was filthy dirty. It would've been a great comparison to my video from last year.

Video-
Fastest run – 69.642 +1, 14th in Pro class, 17th overall

Results-
14/21 in PRO ....Class Results
17/104 in PAX (966) ....Pax Results
These results are from a coned run. If I had run my 69.642 clean I would’ve been 2nd in Pro and 3rd overall with a 55.365 pax time and 994 pax score.

This was my last “big” race of the 2013 season. I may do a small charity event with ClemsonSCC in December, but that will be it.
 
81 - 100 of 130 Posts
Top