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post #31 of 40 (permalink) Old 04-24-2015, 03:51 PM Thread Starter
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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

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post #32 of 40 (permalink) Old 04-24-2015, 04:44 PM
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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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post #33 of 40 (permalink) Old 04-24-2015, 04:47 PM Thread Starter
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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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post #34 of 40 (permalink) Old 04-28-2015, 02:36 PM
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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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post #35 of 40 (permalink) Old 04-29-2015, 04:04 PM Thread Starter
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Who are you calling fat?
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post #36 of 40 (permalink) Old 05-01-2015, 07:34 AM
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Who are you calling fat?
LOL !!

Andres
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post #37 of 40 (permalink) Old 05-02-2015, 10:37 PM
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Quote:
Originally Posted by stigsdad View Post
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 fasterÖfrom 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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post #38 of 40 (permalink) Old 05-05-2015, 09:44 AM Thread Starter
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It's more that the front outside tire is given a more stable contact patch that doesn't get funked up by body roll---you use less of the outside of the tire and more of the inside (of the outside tire)

New update--so far so good--but needs shocks.

http://www.motoiq.com/MagazineArticl...act-Patch.aspx
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post #39 of 40 (permalink) Old 05-05-2015, 11:52 AM
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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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post #40 of 40 (permalink) Old 05-05-2015, 10:02 PM
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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.......

Scott Meyers
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