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Discussion Starter #21 (Edited)
Now that a few companies have developed some parts for the 2014+ cars, I'm thinking about doing some mild STF stuff to make the car a little more interesting--not necessarily more competitive. Looks like Racing Beat and Corksport have bars…now we just need shocks and springs and...
 

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Good blog Per, thanks for sharing. I'll check in from time to time to see how things progress. Be sure to update after you put the new front bar in or any other changes.

I hope to eventually see you in STF (and I think we will ;) ). Even many of the Mini guys are moving on from HS because the Fiesta ST is just too much of a powerhouse. I'd be surprised if Tim C stays in HS with the Mini. Also on local events where we tend to race against others on pax, you got an uphill battle in HS because your index in the future will be based on a smaller car with 50 more hp and 50 more ft/lbs of torque. Either way, best of luck this season and hope to see your Mazda3 out there. :)
 

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Discussion Starter #24
Yep, you'll see me in STF.

16x7.5 wheels on the way….
225/45R16 R1Rs in my garage
Racing Beat bars on the way…
Trying to work out spring/shock package now.

Bear in mind that this car sees 100 miles a day of Cleveland, Ohio roads, year round…so it's going to be mild-ish.
 

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Yep, you'll see me in STF.

16x7.5 wheels on the way….
225/45R16 R1Rs in my garage
Racing Beat bars on the way…
Trying to work out spring/shock package now.

Bear in mind that this car sees 100 miles a day of Cleveland, Ohio roads, year round…so it's going to be mild-ish.
Sweet!

Hey I can respect that. Glad you joined the STF club and looking forward to seeing the build unfold. Kind of interested to see what is out there for a 3rd Gen Mazda3.
 

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If using a spring/shock package, how much gain do you anticipate with the camber plates?

I'm desperately after some camber myself, so thinking of adding a bigger front bar to keep what camber I have and then either going plates or slotting the tops...just not sure how much I can gain with a full-size spring. I know you also get to work with the more raked strut with bottom bolts. grr!
 

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Discussion Starter #29
I doubt that I'll see more than 1.75…with the 6 degrees of caster, that's good, but not great. I'd rather not use 'crash' bolts on the bottom, unless they're factory--which hasn't happened yet.
 

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I'm desperately after some camber myself, so thinking of adding a bigger front bar to keep what camber I have and then either going plates or slotting the tops...
Increasing the front bar will increase understeer, so you might want to adjust the rest of the car to keep the balance as you like. I think the saying is something like one happy tire is better than two unhappy tires, so people with miatas and BMWs (really any RWD car) run a stiffer front bar and may even lift a front wheel through a turn. Sadly with our cars, if we lift a wheel we aren't putting any power down so be mindful of this. I'd be interested to see how the car performs with a stiffer front bar as compared to increased spring rate. I don't know if any STFers on here have tried that route; Adam actually went smaller IIRC.
 

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Discussion Starter #31 (Edited)
As I said, I don't agree with the generalization that big front bars necessarily cause understeer, but lack of wheel rate and resulting camber change certainly do. I linked to the GRM article I wrote which explains some of this. The fast FWD strut-based autocross cars, going way back into the 1980s have mostly used big front bars to go faster…from the Tunnells in their Jettas to Daddio and his Neons (including when he went to DSP and SMF)

It may *feel* slower because you don't have that ZOMG! OVERSTEER! feeling, but it does work.

Per
 

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DSP and SMF probably had LDSs though? (though with certain versions of this...yes once one is in the air, it's essentially open)

The big front bar was just a musing for me (and I already have the part- so it's just experimentation labor and battling New England winter bolts). I'm also on soft OEM springs (and maybe Racing Beat).

I have no idea how Adam does it with the big rear bar and an undersized front bar. I've always been a fan of a bigger rear bar on street 3s, and I liked what my JBR bar did during auto-x runs...but it's plenty tail happy for me just on soft. I can't begin to imagine the hotchkis on max stiff + undersized front. I guess the individual spring rates really work with the bars to keep all 4 corners drivable. With other things like camber plates I guess you can get away with a thinner bar and still keep the outside tire with a happy patch.

Anyway I don't want to threadjack, but I'm eager to see how the camber plates work out with a spring/shock combo. If it works well, I'll be adopting it myself. :)
 

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Discussion Starter #33
This was also on a lot of stock class cars with open diffs.

The stock front bar on the 2.0i is 19mm---that's pretty dinky. The 2.5s is 22mm. The stock MINI front bar is 21.5, 24 or 24.5 depending on what options you have (IIRC)
 

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225/45R16 R1Rs in my garage
Can't wait to see pictures, love that car.

Said that, historically the only R1R proven to work really well has been the 195-50-15 for lightweight cars, According to latest reports from last week's Pro Solo, the new generation of this size seems to have the same characteristics as the old ones.

Said that I would keep your new Toyo's for rain days , and get the BDG Re71-R for dry Autocross. The have proven so far the tire to have among new brands like Rivals S and StarSpecs, specially for a car your size.

The only down side of the 71-R's is the fact they don't offer contingency for Pro Solo's '

Andres
 

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As I said, I don't agree with the generalization that big front bars necessarily cause understeer, but lack of wheel rate and resulting camber change certainly do. I linked to the GRM article I wrote which explains some of this. The fast FWD strut-based autocross cars, going way back into the 1980s have mostly used big front bars to go faster…from the Tunnells in their Jettas to Daddio and his Neons (including when he went to DSP and SMF)

It may *feel* slower because you don't have that ZOMG! OVERSTEER! feeling, but it does work.

Per
Hmm. So I guess the front wheel outer wheel digs in enough to rotate the car? I'd actually be very interested to see how that would drive.
 

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Really nice update.

I used the big front bar approach for a while (Hotchkis 32mm hollow 560#/", stock is 21mm solid 415#/"). Seemed to work pretty well on the soft stock springs and even on my 400# springs with no camber help. However after swapping in the stock bar, camber plates, and stiffer 550# springs; it became abundantly clear I was doing something wrong when I got smoked (by more than a second) at an event by a heavier 3 with less power on the identical suspension (same brand OTS coilovers, camber plates, giant RSB, similar 140TW tires) except he was on 400# front springs. After a few discussions and calculators, the conclusion was my front needed to be softer. Went back to 400#...better. Then to 350#...even better. I immediately went from pax-ing 15th to fighting for top pax at every event. To me it doesn't feel comfy or fast most of the time, but the clock and results ain't lyin'!

I think the car can benefit with a bigger FSB when on soft springs (something less than 300ish pounds) even with the camber, but these cars seem to thrive on an autocross course with soft front ends.
 

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Big Front SB Faster?

Back in the time that only front sway bar changes were all that was allowed, that was essentially all that we could do. So we did it.

As I recall, adding a larger front bar to a number of cars that I ran *always* required an "attitude adjustment" in my driving style; usually significant. Had to be much more careful about charging into corners (kind of my natural style), and become a lot smoother with my steering inputs. Nothing abrupt.

We always thought they helped a car go faster, but not sure if that was really true. Perception is Reality you know.......:chuckles:
 
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