Advanced Suspension Mods

[Advancedynamix]

this is corner 4 where the car felt very balanced. More rear bar would have reduced the amount of speed I could have carried through this corner and corner 3 just before it. I was really gaining ground here on the cars that would out power me up the straight. On the limit the car was a bit tail happy especially in turn 3, which is last place I want to spin (close to 100mph).

[Advancedynamix]

I'm not sure you can get enough to be meaningful here, (except to require a power rack ). Any way to transfer more onto the inside front by firming the opposite rear? Stiffer bar?

I want to be able to adjust my caster so that I can run more rake without the car feeling nervious. The rake will put more weight on the front wheels. It will also allow me to run less camber, which would make a difference in this corner, especially with the wider rims, that with the little bit of positive camber on the inside, gained from the caster, would put a little more tire on the wilcox pavement. The steering is very light right now, so I can add a few degrees of caster without my arms getting tired.

HAHAHAHACarolyn just walked buy, " Nice picture, but look at the tires!
he's not transferring enough weight to the front" HAHAHAHAHA......

Carolyn has yet to show me the technique required to weight the front end while powering uphill. lol. That's a trick I gotta see for myself!
The car was hooking up well in this spot with the current engine, but I'm looking to add 50 ft.lbs of torque to the mix, so I'm going to need to get more sticky rubber on the ground. I'm not sure if more rear bar is going to help because the car already rotates a little too easy. Adding torque while making the chassis more apt to rotate sounds like a recipe for more off track exploits. lol.

Ryal, it's good to see you back on the forum! Carolyn should get on here too, after all she does own a Festiva

[Dragonhealer]

HAHAHAHACarolyn just walked buy, " Nice picture, but look at the tires!
he's not transferring enough weight to the front" HAHAHAHAHA......

[Dragonhealer]

I think more caster would help my inside wheel to stay more level and have more traction, as well as giving more support to the outside wheel. In this picture you can see my inside wheel has very little contact patch.

I'm not sure you can get enough to be meaningful here, (except to require a power rack ). Any way to transfer more onto the inside front by firming the opposite rear? Stiffer bar?

[zoom zoom]

io^ psh, that's nothing, my fiance would totally smoke you in her minivan. We were out yesterday and I swear we were on 2 wheels on half of the backroad we were on. She told me "if this was a car you wouldn't be crying about my driving" LOL.... she definately knows how to use the brakes/gas through curves, now if only I could get her to use the brake sooner..

[Advancedynamix]

I think more caster would help my inside wheel to stay more level and have more traction, as well as giving more support to the outside wheel. In this picture you can see my inside wheel has very little contact patch.

[Advancedynamix]

Right now my 13's are 38mm offset at 5.5" width. There is plenty of room now, but I know with the 7" rims I'll be cutting it real close, and may need to use spacers or at least get creative with a flapper disk on my strut. I should be able to get away with less camber though, so things should clear. Fingers are crossed. lol.

I don't think Team dynamics drills dual patterns into their rims, but I don't know for sure. They will build the wheel in any bolt pattern you choose though, and most smaller front drive cars here in the states are 4x100 or can be converted relatively easily. The rear drive cars that use 13's are spoiled with wide options in ET0-15 offsets. heck, I even have several sets of 13x6" BBS wheels. Wish they were a higher offset.

That's a nice Pug you have there, I'm a little jealous. If i went to Germany I could probably just look at the cars you guys have for days! a friend of mine had one of the few R5 turbo's that made it over here and it was so much fun. I think the U.S. market is starting to accept and welcome sub compacts again. The smart car doesn't sell like it does in Europe, but they have lasted longer than a few years and now the 500 is selling pretty well. I see Hyundai accents everywhere and the new Chevy sonic seems to be selling well. VW has been teasing us with the Polo for years and ford gives us the boring version of the Fiesta (they wont even send the 2 door over for the rally drivers!) but both those cars are almost midsized now. It'd be nice to have a bare bones 2000lb sub compact with a nice turbo engine to play with. One can dream. Until then, it's Festivas for me.

[Arnie]

I love all the hatch options here. Clio Cups are wonderful, even the Twingo RS is really nice. Pugs aren't as good as they used to be (not like the 205 GTi/106 XSi or Rallye). Small VW's like the Lupo GTi and Polo GTi are fun luxury versions of hot hatches. Heck, even the new Scirocco is not bad. I'm so happy to be back and to have all these small car options. What's nice is a lot of these cars are either rallied or have a single make series so there are performance options out there. Its like wagons. No one likes wagons in the US, but in Europe, they're basically like the Pick-up. The performance wagon options here are just awesome.

Can team dynamics make the wheels with double BCD's? As much as I don't like those types of wheels, it would definitely help with getting people to buy. And of course choosing an offset that can cover a couple of options with perhaps an addition of a thin spacer (hate spacers too! lol). Or would you go with 4x100/Aspire BCD?

I also have tire limitations too on my Pug if I stay with 14" wheels. Semis are Kumho V70, Toyo R888 and yoko A048 in 185/55-15 or 185/60-14.

yes, the smaller diameter may be an issue. it will depend entirely on what the lower clevis looks like on the strut used. I had contact issues with the TEIN setup on the front knuckles using 13". Had to go with 14" Miata Daisies.

Here are pics of some Honda 13"ers on the TEINs I had, 13x5, 40ET:

so how close are your 13"s to contacting things? This close?












Here's my Pug:

[Advancedynamix]

Yeah, the only other choice I have in this size (185/60-13) is the Yoko AO48. We don't get a lot of small track tires in this country unfortunately. The only reason we get those two selections is because they are common on Formula Fords over here.
The AO48 has a softer sidewall than the r888, so I know better than to go that route.
Wide 13" rims in the proper offset are another hard thing to come by over here. I'm currently having Team Dynamics (U.K.) make me a set of 13x7 wheels in a 35mm offset to see how that works out. If I like them I may order a dozen or so sets to sell here in the states because I know of a bunch of small car enthusiasts who could use them here.
With the 7" wide rims I'll have more tire options. Several compounds/manufacture of slicks are available in a 7" width and around 20-21" diameter, as well as the legendary Nitto NT01. I'm not sure how the car will like the 7" wide 13's but we'll see. I have 15x7's on it for the street, but the smaller diameter may hit the knuckles.
You get a lot of cool sub compact and compact cars in Germany that we never saw here. I'd love to have a 205 or 206, Cleo, Lupo or Polo, MG Metro, or any of the other neat econo boxes that are not much for concern in Europe, but would get stares here. lol.

[Arnie]

Yeah, that's nasty. I agree, the 5.5" wheel is probably too narrow if you're using that much sidewall. Toyo sidewalls are a bit softer, too compared to others, so that doesn't help your situation. 6.5 to 7" would be a nice setup if you can find a wheel with a decent offset.

I agree that the Festiva suspension is actually a pretty nice and flexible design. Obviously, i wish there were more off the shelf options in coilovers, for example. But I do like the coilspring rear/trailing arm. Its still fairly compact but the coilspring setup makes suspension tweaks a lot easier. My Peugeot uses a torsion bar rear suspension. Its even more compact but tweaking torsion bars is a pain and expensive compared to coilsprings.

Great discussion!

[Advancedynamix]

It's possible to do this to a set of R888's in less than 1000 miles (with absolutely no burnouts). lol.

You can see that my tire pressure is too high, but I'm still folding the tire over, hence the remaining tread on the outside of the contact patch, but the wear all the way down on the sidewall. My cure for this is going to be some 13x7" wheels to support the sidewalls better. These 5.5" rims are too narrow. But, this goes to show that the stock Festiva chassis (no cage, no strut bars, no sway bars and stock rubber bushings) is rigid enough to destroy more rubber than will fit under the car! Phenomenal!

[nitrofarm]

^ Thanks for the much needed lecture my friend. You are wealth of knowledge and a HUGE asset to this community. Have a great weekend!

[Advancedynamix]

Advance I'm glad your talking sway bar mount points again..Its still a gray area for me.My pea brain cant get past the fact. That the sway bar is the control arm.And the control arm is the sway bar.So when we start talking about adjusting the sway bar. I automatically think we are actually changing the LCA attach point.Which way are you going to move it.Fore/Aft or UP/Down? Thinking out-loud,I cant really envision much Fore/Aft adjustment.Because going to far would start to put the inner LCA bushing into a bind right? But you said you want some more Caster during hard corners.So I could see how a little would help this.
And if you move the LCA Up/Down (which I have picked many peoples brains about). Isn't that actually like changing the Anti-Squat,on a true Independent front suspension. ie "H" arms......See why I confuse my self into a corner. :nono: The reason I assume this is because of the "Torque" Being applied to the very front of the car via the control/sway bar. See where I'm going.Or am I a blind man walking into traffic drool

You bring up some good questions. For this car I would only move the sway bar (or front control arm mounting point with the way you are viewing it) for and aft to adjust the caster angle. Since it doesn't need to move much (1/4" max) the LCA mounting bushing should be able to compensate. It will only change the attitude of the LCA by a few degrees. They may show fatigue prematurely, but anyone who is going to make use of the extra caster angle will be wearing them prematurely anyway. Lol.
I won't be moving the control arm mounting point on this car. I want to keep Tweak simple, and to make that modification justifiable would require a complete re-engineering of the front of the car (find pictures of that silver pride 4 door that was converted to a 2 door and has a B6d on carbs to see what I mean by that). The stock festiva doesn't have enough fender well to accommodate much higher roll center, and the strut mount is also too low for that mod. However, as Arnie pointed out, modifying the control arm itself to essentially raise the ball joint while lowering the control arm is a way to make the suspension more usable. This would have several benefits. I'm not comfortable with bending the control arms though. I think he was talking in terms of meeting the requirements of a spec class, so it would have to be a stock part. In that case bending the stock part would be an option, and has been done successfully on other cars. I may build adjustable LCAs in the future, with removable ball joints (323/Capri parts). But for now, I'm going to show what can be done with stuff anyone can buy.
You can't think of the Festiva front suspension like an H arm or A arm system. That's why your getting confused. It's essentially a trailing arm system. The sway bar acts like a drag link or trailing arm while the control arm supports lateral forces and acts to add camber as the suspension is compressed. It's a multi-link suspension that is not only very effective, but also extremely light weight. This front suspension system is one of the Festivas "secret weapons".
A trailing arm setup is the best setup for traction, that's why everything from the VW bug to complex 4-6 link trucks hook up so well. To have a front drive car with a trailing link is like magic! I've never driven another 1700ish lb car with 160ft.lbs of tq and an open diff that could hook up, and this car begs for more! Unbelievable!
A trailing arm/link suspension will use the engines TQ to apply downward pressure to the driving wheels. Easiest way to grasp this concept is to watch a motocross race, the torque of the engine is driving the wheel down as the bikes are accelerating. The "swing arm" on a dirtbike is an example of the purest form of a trailing arm. Traction bars and drag links are also examples of trailing arm type suspension. Trailing arms also do a great job at bump absorption since the arc of the suspension travel is naturally absorbing the energy that's coming at it from the front. And last but not least, a trailing arm suspension is better at controlling body roll than an A arm or H arm suspension. Because that energy is opposite it's natural path of travel, it is less apt to roll than other types of suspension designs.
So here's the kicker, the festiva has this great suspension design on all 4 corners! The rear is also a trailing arm! Excellent!
So you may be wondering, if the trailing arm is so great why do manufacturers use anything else? That's because the trailing arm is difficult to package. As a vehicle gets heavier the strength requirements for the trailing arm suspension become such that it's not cost effective to design this into a vehicle. Also, as a vehicle gets heavier it is usually less dependent on all available driving traction. Trailing arm suspensions are also difficult to design when wide tires are necessary (the festiva is perfect example of that, lol). That doesn't mean that trailing arms aren't used widely, because they most definitely are, but some great cars like the corvette lots of Ferraris formula cars (except formula V) and many many other great handling cars use other means to control the rough stuff. Most of those cars couldn't package a trailing arm suspension.
Sorry for the long winded rant.

[nitrofarm]

Advance I'm glad your talking sway bar mount points again..Its still a gray area for me.My pea brain cant get past the fact. That the sway bar is the control arm.And the control arm is the sway bar.So when we start talking about adjusting the sway bar. I automatically think we are actually changing the LCA attach point.Which way are you going to move it.Fore/Aft or UP/Down? Thinking out-loud,I cant really envision much Fore/Aft adjustment.Because going to far would start to put the inner LCA bushing into a bind right? But you said you want some more Caster during hard corners.So I could see how a little would help this.
And if you move the LCA Up/Down (which I have picked many peoples brains about). Isn't that actually like changing the Anti-Squat,on a true Independent front suspension. ie "H" arms......See why I confuse my self into a corner. :nono: The reason I assume this is because of the "Torque" Being applied to the very front of the car via the control/sway bar. See where I'm going.Or am I a blind man walking into traffic drool

[zoom zoom]

Absolutely speechless.

I'm not familiar enough with basic dynamics to understand advanceddynamics.