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-   -   Simplest Bestest Mods to tighten up steering, turn in and body flex (https://www.ft86club.com/forums/showthread.php?t=144981)

Transport3r 04-24-2021 08:23 PM

Simplest Bestest Mods to tighten up steering, turn in and body flex
 
Quote:

Originally Posted by 7 skulls (Post 3426800)
Way back when I was researching these, I came across a video of an frs doing auto cross. The POV, from a gopro suction cupped to the car, focused on the door/body seam and the amount of gap variation was a little scary. After these were installed, the door gap was stable. Sold me.


I remember that video, it was kinda crazy.

The new cars are 50% stiffer so they might not work as well on them.

grumpysnapper 04-24-2021 09:59 PM

Quote:

Originally Posted by 7 skulls (Post 3426800)
Way back when I was researching these, I came across a video of an frs doing auto cross. The POV, from a gopro suction cupped to the car, focused on the door/body seam and the amount of gap variation was a little scary. After these were installed, the door gap was stable. Sold me.

Surely thats the door "moving" inside the aperture, not the critical aperture structure deforming? Two very different things?

Doors/windows close against flexible rubber seals in order to seal properly (in many different conditions) and repeatedly over the life of a car. They are not designed to be totally solidly mounted.

I would have no issues with TRD claiming it holds the door in place to a greater degree. Whether the door "needs" to be further held in place is another question, that they might need to put a case for (in order to charge the price they ask for the product).

I know that ultimately it doesn't really matter, it always a personal choice, but it genuinely irks me when cynical salesmanship over reaches, on purpose, to mislead genuine enthusiasts, many of whom don't have a lot of spare cash to waste.

x808drifter 04-25-2021 07:10 AM

Quote:

Originally Posted by WC-BRZ (Post 3426692)
Hey gang, why do most wheel/tire setups go with an equal tire size on all four corners? Is it just for lateral stability?

Wouldn't a thinner front/wider rear tire be better as you'd still have some of the responsiveness and quick turn in from the front?

The McLaren Senna still runs a 245 front tire and if I'm not mistaken the 600LT and 720S also run fairly thinner fronts. In fact, I believe most supercars do this.

I'd imagine that a good quality tire compound would take care of added grip and you could stay with a 225-section front and feel free to go to 245 rear if needed.

Any handling/steering feel downsides by going with a non-staggered setup on our platform?

God I hope this is a troll post.
but I'll bite.

Cars that have staggered offsets usually have them for rear grip reasons.
McLaren has a mid engine layout. More weight being tossed around in the back and WAY more power. Need fatter tires.

The twins are well balanced from to back and has a rather stable wheelbase.
So there is no reason to go staggered. It'll just add understeer.

Obviously simplifying the crap outta this, but those ate the basics.

nikitopo 04-25-2021 07:48 AM

Quote:

Originally Posted by WC-BRZ (Post 3426692)
Hey gang, why do most wheel/tire setups go with an equal tire size on all four corners? Is it just for lateral stability?

Wouldn't a thinner front/wider rear tire be better as you'd still have some of the responsiveness and quick turn in from the front?

There is a factory staggered setup here (GR wheels), but it should be combined with a suspension change, a bigger rear sway bar, rear chassis stiffening and a differential improvement. So, it is not an easy change and for sure not cost effective.

Personally, I prefer to stay with an equal size wheel/tire setup on a 200tw 205 tire. In this way, I keep the responsiveness and quick turn in without the need to add an additional weight on bigger wheels/tires and other reinforcements. The disadvantage is that I have to spend more money on tires, but as usual it is all about compromises.

WC-BRZ 04-26-2021 12:01 AM

Quote:

Originally Posted by x808drifter (Post 3426870)
God I hope this is a troll post.
but I'll bite.

Cars that have staggered offsets usually have them for rear grip reasons.
McLaren has a mid engine layout. More weight being tossed around in the back and WAY more power. Need fatter tires.

The twins are well balanced from to back and has a rather stable wheelbase.
So there is no reason to go staggered. It'll just add understeer.

Obviously simplifying the crap outta this, but those ate the basics.

I don't think the rudeness was necessary 😕

If you are as smart as you think yourself to be, then how come you need to "simplify the crap outta this" and not just give the proper, in depth answer?

With respect to your comment about the cars being mid-engined and a rear, wider tire supporting the extra weight - I get that!

I should've mentioned that - and I'm pretty sure I'm not mistaken here - cars like the S2000 and M2 also have factory staggered setups without there being any need to support extra weight in the rear. So they run staggered setups to support more power and what I was trying to get at is that how come modified 86s (usually with more power than stock) still run non-staggered.

Wouldn't a staggered setup on, let's say, a 300hp 86 be better as you'd retain the turn in response and get the wider rear to handle the added power? The resulting understeer could be dialed out and since I hardly ever see this being done I figured I must be missing some other benefit(s) of a square setup.

So that's pretty much what I was trying to figure out and your smug response seems pretty unnecessary.

Note to self: better to just search up these things next time rather than getting into pissing contests on these forums...what an incredible waste of energy and also quite the letdown

WC-BRZ 04-26-2021 12:05 AM

Quote:

Originally Posted by nikitopo (Post 3426873)
There is a factory staggered setup here (GR wheels), but it should be combined with a suspension change, a bigger rear sway bar, rear chassis stiffening and a differential improvement. So, it is not an easy change and for sure not cost effective.

Personally, I prefer to stay with an equal size wheel/tire setup on a 200tw 205 tire. In this way, I keep the responsiveness and quick turn in without the need to add an additional weight on bigger wheels/tires and other reinforcements. The disadvantage is that I have to spend more money on tires, but as usual it is all about compromises.

Ok, so bottom line, it seems that to dial out the understeer resulting from a staggered setup you're adding more parts, which in turn, means more cost, complexity and tuning to get everything running right.

In conclusion I guess it would be up to the owner to decide how badly they'd like to keep that turn in response.

nathand 04-26-2021 12:46 AM

Quote:

Originally Posted by WC-BRZ (Post 3427031)
cars like the S2000 and M2 also have factory staggered setups without there being any need to support extra weight in the rear. So they run staggered setups to support more power and what I was trying to get at is that how come modified 86s (usually with more power than stock) still run non-staggered.

Lots of S2000 run 255 all around for autocross in spite of being staggered from the factory.

Often times there is more room in the rear for wider tires. Give that, some people opt to run the widest tire that fits to get power down and that ends up staggered.

You can take that to the other extreme like drag racers and run skinnies up front. :-) It's all about what you want out of your car.

But, if you run 225 front and 245 rear on a mildly modified 86, you're probably gonna get a lot of understeer unless you've done some extreme things.

And what good is nice turn in if it quickly turns into understeer?

x808drifter 04-26-2021 08:29 AM

Quote:

Originally Posted by WC-BRZ (Post 3427031)
I don't think the rudeness was necessary 😕

If you are as smart as you think yourself to be, then how come you need to "simplify the crap outta this" and not just give the proper, in depth answer?

With respect to your comment about the cars being mid-engined and a rear, wider tire supporting the extra weight - I get that!

I should've mentioned that - and I'm pretty sure I'm not mistaken here - cars like the S2000 and M2 also have factory staggered setups without there being any need to support extra weight in the rear. So they run staggered setups to support more power and what I was trying to get at is that how come modified 86s (usually with more power than stock) still run non-staggered.

Wouldn't a staggered setup on, let's say, a 300hp 86 be better as you'd retain the turn in response and get the wider rear to handle the added power? The resulting understeer could be dialed out and since I hardly ever see this being done I figured I must be missing some other benefit(s) of a square setup.

So that's pretty much what I was trying to figure out and your smug response seems pretty unnecessary.

Note to self: better to just search up these things next time rather than getting into pissing contests on these forums...what an incredible waste of energy and also quite the letdown

Garbage in, Garbage out.
If I was trying to be rude I wouldn't have even bothered trying to explain the basics, I would have just told you to search.

You started by comparing a high power mid engine car to a low power FR.
The gives 2 first impressions.

1: You don't understand even the basics of front vs mid engine cars and why mid engine cars have wider rears.
so I feel I need to simplify the crap outta it to get the bare basics across.

2: Using your two wildly different cars in the original comparison.
The post must be a troll/joke post.


If you had led off with the comparisons with the M2/S2K like you did later I would have taken it much more seriously.

It's almost always better to run a square setup if possible and use the rest of the suspension to fine tune the rest.
Fatter rear or front tires are used to make large changes to over/understeer and general vehicle stability.
IE: when you cant get any more grip out of the suspension.

Wheelbase also comes into play.
Short cars will rotate easier and be harder to catch if they start to slide, so some intentional understeer may be desired. (Lots of OEMs also make cars understeer intentionally) M2/S2K for example.

In autocross however oversteer is usually desired quite a bit more so like in nathand's description the S2k's run a square setup.

It is also very easy to go too wide with the tires.

A 235F/245R wont destroy the cars handling but that is assuming the you need that extra bit of tire to put the power down. And at that point you should have enough power in the rear that the rear width is no longer causing excessive understeer so much as its keeping the rear from stepping out under throttle.

strat61caster 04-27-2021 03:11 PM

Quote:

Originally Posted by WC-BRZ (Post 3427031)
I should've mentioned that - and I'm pretty sure I'm not mistaken here - cars like the S2000 and M2 also have factory staggered setups without there being any need to support extra weight in the rear. So they run staggered setups to support more power and what I was trying to get at is that how come modified 86s (usually with more power than stock) still run non-staggered.

Show up to a track day or autocross and most of those S2k and Bimmer's (not just the M2's but the all the M cars from E36 on up) switch to square wheel/tire setups if the ruleset allows, most cars leave the factory with terminal understeer and aren't set up for maximum performance despite what the advertisements say.

Less bimmer crossover on this forum but with the front struts similar to an 86's and lack of camber gain they need the front tire as much as we do.

Broz 05-12-2021 06:27 AM

Thanks everyone for your comments, experiences and opinions. Much appreciated!
Sorry for the delayed response ... been a few 85+hour weeks finishing up a movie:(

Car is currently on stock wheels/tires.
Have a set of pretty but dusty OZ Superleggeras in storage needing new tires.
Previously mounted w/S03 Pole Positions carried over from my 2003 WRX....which I loved (stiff sidewall and dry/wet traction). Based on the previous comments, will likely upgrade to S04s this time around, not all seasons after all.

Then incrementally upgrading bushings seems like a no brainer ... and steering rack lockdown (?). I'll update this thread as I go and will definitely be back with more questions:)

Cheers,

Broz

scion fr-s 05-13-2021 03:06 PM

Quote:

Originally Posted by Broz (Post 3424494)
Hi guys,

After 4 long years in storage, super stoked to have my 2013 FRS back on the road. The steering input/response and oversteer/tail happiness are what I love most about the car.

I’d like to make it even better.
Any suggestions for the first mods to tighten up the steering feel and turn in alittle more.
With moderate expectations:)
Avoiding any additional jarring or bouncing around. A little more NVH is understandable.
Keeping in mind I'm now switching from stock 215/17s to 245/18s (either Yokohama Advan Sport A/S+or Michelin Pilot Sport A/S 3+ Tire).

I’m cautious to overdo things. Based on previous experience (overly) modifying a 2003 WRX with every item in the Whiteline catalog… which in the end would tramline, bump steer/wheel hop and chip teeth crossing any highway/bridge seams.

Thanks for any advice/input/experiences!

BBroz

I would recommend Whiteline Steering Rack Bushings and Perrin Steering Rack Lock Down combo. Also, a good set of 200 treadwear tires will help. Many above-mentioned camber bolts and alignment.


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