2G How to improve handling characteristics of my AWD 2g?

[Black95TSIawd]

Chassis stitch welding also bumps you up into certain "all out" classes. I wouldn't bother to do that for just a street car nor would I bother unless I was building a balls to the wall race car. Paging @greengoblin

 

[Black95TSIawd]

I love it when 2G hard top guys saying that their cars are "wet noodle"... You guys haven't seen a noodle until you tried a Spyder!

OP, I would love to see your current wheel fitment.

I guess its more of a comparison to other cars. Try getting into a newer boost buggie, S2000, BRZ/FRS, or even an old honda. Makes our cars feel like a wet noodle.

Although, good strut bars, fender braces, and the RRE lower brace really, really helped out with my Talon.

 

[Black95TSIawd]

We can assemble a proper coilover kit based off whatever the customer is looking for. Most of the 2G guys tracking the car are looking for as much stroke as possible, which goes hand in hand with a slightly taller shock. Those looking for those aesthetics of a more flush car simply need to let us know, and we will go ahead and supply shorter cartridges to achieve a lower ride height.

Yes, we want travel, especially droop in the rear, but that doesn't necessarily mean we want a taller shock. A good mod for koni yellow's is to take an inch off... half inch on the body and half inch on the shaft. Although, I've never held any of your stuff in my hands for comparison.

 

[orangedsm]

Great thread! Hits home for me as I'm doing many of the same things with my GST.

One thing I noticed that no one has mentioned, wheel weight and the Continental DW tires. Your wheels are heavy, get lighter wheels and you'll improve your handling and steering response. The Continental DW's are known to have a VERY soft sidewall, which is hurting your turn-in/responsiveness. I had Continental DW's on my MINI Cooper (R53) and switched to Advan AD08 with no other changes and the turn-in was significantly improved.

Just a thought for when you replace your tires next time.

 

[herostar]

Great thread, lots of good info here!

My quick/easy suggestions for a starting point:
-Front strut tower bar
-Rear strut tower bar
-Rear swaybar
-Front end bushings (which ones is up to you, the more the merrier)
-Get an alignment done if you haven't recently

 

[bjones18]

And... just when you "bolt-in" / "weld-on" the "shiney red part..." ask yourself... Why does the EVO or M3 handle/feel so well... without this? Remove the EVO brace... not much change? Or night vs day?

I have witnessed multi-million-dollar instrumentation on vehicles and trained drivers see/feel ZERO difference when a part (strut brace) is added/subtracted (on a chassis mule car). UCA loads are ~1/3 that of LCA loads. Need depends on your structure and loads.

Vehicle dynamics is tuning. And every "instrument" (car) has different "tuning knobs." Further... all knobs set to "10" does not result in success. Knowing what each knob does... searching the "hidden" knobs to fine-tune... and being able to hear (feel) the changes as you turn the knob; is key.

And just when you are winning the "arm-chair-racing" game ask yourself again... does the EVO or M3 do this? why or why not?

Most aftermarket shocks are stiffer than OEM. Why? So when avg-Joe replaces his "just-fine" shocks, he feels a difference (and didn't waste money). Red paint is a key ingredient to many aftermarket parts. Raise your hand if a black-bushing or black-control-arm 'pumps your testosterone/adrenaline' as much as a red one. Why is this? If you can "lower your vehicle weight" by removing that "holy grail" part you purchased/installed and cannot tell any difference in a blind-part-swap...should you lighten it up? Is the part "snake oil" or could Your seat time use some improvement? Do you care? Seriously, car guys/girls love to talk about their baby... and make it the "best" they can for conversation, which is perfectly fine. Show cars are cool. Performance is different than show. Generally speaking... in performance there is a winner and a loser. Losers who can't figure stuff out... don't become winners.

If you want an ace in your back pocket, research and buy good tires. The only thing holding you on the road... dry, wet, snow, ice, are four contact patches with the combined area less than a sheet of paper. Rubber is not all created equal.

And for the guru's... our double ball joint front suspension has rear-steer (gear aft of wheel CL). Through turn how does the virtual center move? does ackerman change... inside to outside wheel? Why did BMW (inventor of DBJ) switch to front steer when replacing ball-nut gear with rack & pinion? (early 90s) Why does high-angle inside wheel tie-rod-load "spike" with rear steer DBJ? is the inner-wheel tie rod close to Toggle? Are the knuckle-steering-arm lengths changing with instant center movement? Inside-turn knuckle-steering-arm getting shorter or longer? How does front steer improve this? does front steer run through EastWest oil-pans?

 

[mitsumikey]

I was inspired by green goblin and this thing has been stiffened starting from the chassis. Not done yet. Weight reduction and balance with stiffening are priority. Also been collecting Bobby's suspension bits and the DG/koni setup with coaxial top hats. Alot can be done with time and money...

 

[GRNDSM]

You missed that hole in your roof!

 

[mitsumikey]

You missed that hole in your roof!

A price to pay for luxury I am honestly hardly worried about it the frame is/will be stiffened so much

strut towers are welded on solid. ect. CF sunroof with a hand crank will be going up there.

 

[EC17PSE]

i agree that the moon roof is not really strength and structure at all, thats the pillars job! the roof is just a skin and it does nothing really, seam welding does alot more good then a cage ever will and we never do the cage 100% how it should be anyway, I know I cannot because of time and without having to redo my oem dash and im not allowed to ditch it for rules and making my oem dash work with these bars is going to be a pita,

so having a moon roof is fine as long as its lightweight. less weight above the C of G so less wobbling and will make for a better handling car

 

[Th3ory]

Heres a quick thought outside the box, seats.

The seats in my srt4 hugged better then my dsm seats. Seats wont help with actual ground control, but will help hold you in place while pulling corners.

I have seen a few dsms with evo Recaro seats, someone used to make the adaptor brackets. If people are going to the extream of handling in a dsm, might consider upgrading the seats from the smooth, slippery leather in a dsm

 

[2gmitsueclipse]

Heres a quick thought outside the box, seats.

The seats in my srt4 hugged better then my dsm seats. Seats wont help with actual ground control, but will help hold you in place while pulling corners.

I have seen a few dsms with evo Recaro seats, someone used to make the adaptor brackets. If people are going to the extream of handling in a dsm, might consider upgrading the seats from the smooth, slippery leather in a dsm

For those who aren't ready to make the investment into seats and/or a proper cage/harness setup, I have had very good results using the CG-Lock to keep my body from moving around on OE seats for Autocross, RallyCross, and track days.

You must be logged in to view this image or video.

You must be logged in to view this image or video.

 

[95REGF150]

i agree that the moon roof is not really strength and structure at all, thats the pillars job! the roof is just a skin and it does nothing really

I gotta disagree Bobby. Skin adds shear strength to a structure just like walls in a building. Nail some 2x4's into a rectangle and then try and pull 2 diagonal corners of that rectangle towards each other. That structure will give way no problem. place a sheet of plywood over the structure and nail it off and all that give is gone.

Now apply that principal to the roof structure of the car when it is being torsionally twisted. The structure running along the outer edges of the roof is going to give some but with a full roof sheet attached it is going to have much more resistance to this force than without.

 

[EC17PSE]

I gotta disagree Bobby. Skin adds shear strength to a structure just like walls in a building. Nail some 2x4's into a rectangle and then try and pull 2 diagonal corners of that rectangle towards each other. That structure will give way no problem. place a sheet of plywood over the structure and nail it off and all that give is gone.

Now apply that principal to the roof structure of the car when it is being torsionally twisted. The structure running along the outer edges of the roof is going to give some but with a full roof sheet attached it is going to have much more resistance to this force than without.

But the main structure is essentually a square so the roof skin is useless, just press on it and you will see how flimsy it is giving zero added strength, its why its so thin and ot braced in the middle with either a X or even a straight line like some cars are,

If it was critical then all these glued on roof skins would not excist as they dont offer strength like that but a small weight reduction, put 1 swaged sheet of metal along the skin and you have a much stiffer roof and structure but leaving it alone its not doing alot,

Also skins are soo thin and strsight with zero creasing that its not offering any strength to it either, moving it sideways its doing more then up and down and thats why i said go push in the roof and watch it flex and bend in, if that was some kind of added strength then it would not be that flimsy, if it was doube skinned however then thats a different angle and it will add strength like doors and trunks, hoods etc etc,

 

[ChiefMunga]

I think I just got educated by an experienced OG dsm racer. Thank you for this.

I owned an Evo IX MR for ten years, sold it last November only because I wasn't driving it. Your criticisms are valid. The Evo is a wonderful car and it's a bit perplexing that it drives so damned well when its design to my uneducated eye appears to be worse, yet it isn't worse at all but drives so much better.

There's a ton you CAN do to the Eclipse to make it better, and I can tell you that you CAN definitely make it overall faster than the Evo. The driving experience though I don't think will ever quite match the Evo as there are some things that are just different and are very very costly to try to make the same. As a 17 year Eclipse owner, 5 year Eclipse racecar driver... I think it's unrealistic to get them to match.

Let's address your specific concerns:
Quick turn-in/sensitive input
I'm brain storming quickly here, but here are my thoughts:
- Roll center improvement. The Eclipse rolls over easily in stock form, whereas the Evo due to its suspension design stays relatively flat, like very nicely flat. You can fix this however. I did it with a front subframe modification but the guy who does them doesn't anymore. There is hope though. An alternative modification to the mounting of the front LCA can accomplish roll center resistance increase, and Paul Volk, aka 99gst_racer, sells such an arm. Now I haven't yet tested his piece to see how it performs (it's being installed on my racecar now actually) the theory is sound. So that's where I would go.
- The Evo's bushings are simply much newer and likely have less miles than your Eclipse's. Since doing a full rubber bushing refresh is near impossible for various reasons, I would suggest a polyurethane kit for a street car. This is a lot of work to do, or money if you pay someone, but it should refresh your suspension's response to better match or beat the Evo's.
- The Evo has a much tighter ratio steering rack. There is no rack modification to change this. The only option I know of that might help is what's called a Steering Quickener, which is a device that you must install in-line in your steering column that multiplies your steering ratio and raises it, give you quicker turning. This is a custom job and could be pricey. I have totally debated doing this one day but keep putting it off for other things.
- Better shocks. Not sure what shocks you have but chances yours aren't as good as an Evos. So move up. The first shock to me that felt like a match for the performance was a KW V3. Other DSMers swear by the Koni Yellows but they are a class below the KW V3 in price and in my opinion performance. You're looking at paying upwards of $2500 for a KW V3 setup due to having to source new springs and top hats.
- Setting 1/8" toe out up front, 1/8" toe in in the rear.
- Better tires have stiffer sidewalls and this translates just a tiny bit to responsiveness and turn-in. So what tires do you have?

Ability to apply more steering mid-corner without understeering/upsetting the chassis
- This too is pretty much everything I said before. Really, all the things mentioned in the last section do apply here.
- In addition there's your alignment. You want roughly a 50% ratio for front to rear camber for balance.
- Proper suspension tuning is critical here. Getting your spring rates right, plus getting the damper settings right, makes all the difference, in addition to the quality of the damper. I recommend to everyone a 10% higher rear spring rate from my personal experience, but that does affect driving comfort unless you have a good shock.

Overall feedback through the steering wheel
- Overall I don't find a huge disparity on the race track, or street driving, between the two cars when it comes to feedback. It's just the Evo is so much tighter that it feels it gives more, but it really isn't giving more information. It's just your feedback may be hampered by worse tires, softer bushings, a worn steering rack... hard to say. If you work on the other stuff, this might improve surprisingly to your liking. So don't worry about this right now.

Oh wait, I forgot one thing for all of these. Don't lower your car. Really, don't. It screws up the suspension geometry. People go ga-ga over my car with how it looks, and how fast it is, and how when it's by itself it seems so low to the ground because of the aero body. However set my car next to other DSMs and people are very confused. Mine is way higher than most because I sit near stock ride height. Why? It restores everything the designers built into the suspension that you take away when you lower it: roll resistance, anti-dive, bump steer, anti-squat. All these things are key for a proper handling car and lowering ruins every single one. I lowered my car back in the day until I was educated by a very experienced DSM racer and then I saw the light.

Ok I gotta get back to work.