MRAMG1

Okay guys:

I have the mod bug BAD

What I am asking here is what mods to suspession do you have and what decrease in track times you saw?

I am not looking for subjective info, like, my car feels tighter, rides smoother/rougher as this is all biased info. Sorry to sound like a TA, but I would like to do some real mods like Eibach springs, Coil overs, sway bars, IF they showed ANY REAL DROPS in track times.

Could some one help like AMDman, PC Valkier, Fifth, etc, etc who does track our toys?

Please let me know which track and the time drop, like Mid ohio, watkins glen, Summit point, Beaverun, Nelson Ledges, Poconos, etc, etc.

I have the coin, if these mods actually helped. I just don't want to change something for the fun of it, or for the feeling.

THANKS IN ADVANCE to all the great people on this site for all of your help

See yeah

Nuvolari

The best mod by far would be to buy proper R-compound tires. Lap times should drop about 3 seconds per lap on an average road course, the feel of the car will increase, and they are much safer to drive at high speeds.

With regards to the suspension I cannot comment specifics on the Mercedes however a set of well matched coil overs along with a performance alignment and corner weighting (very important) should see another 2-3 seconds a lap.

Tires and suspension should be worth a good 5 seconds total. Don't spend a dime on the engine. There is a ton of time in the car as it stands.

FYI: My backgrond is 15 years as a semi professional race driver, performance driving instructor and expert (not self-proclaimed) in the high performance realm of motoring.

MRAMG1

Hey there Nuvolari:

yeah, I know all about R tires, have went through WAY TOO many in my day. I just don't feel like spending $3000 for rims and tires for two or three days a year

I agree they ARE the biggest gain for the buck, and you are right on about power, as this is only a SMALL gain, as testimony by my 91 stang I had in the world challange series a few years back.

I am still hoping that someone has some GOOD info on available suspension mods for our toy with REAL world data. I tried everything under the sun on my stang, 5 link, coil overs, even moved the K-memeber forward for 2 degrees of MUCH nneded caster. Some worked, some didn't.

AS far as the conrner weighting, I am not sure of any BIG gain here with a street car. Yes it does help with a gutted full blown track car, NO DOUBT. However, I plan on keeping my interior just the way it is, and can't see slapping on any more weight to try to balance her out, except for me going on a diet,

I appreciate your input my friend and thanks

See yeah

Fifth Ring

I've never raced nor timed my own laps, so I can't give meaningful data. But I agree that you should start with wheels/tires. Consider un-staggering and use 245 series tires on all four corners.

By far, the best way to reduce lap times is driver education. I know you've got a resume, but there's always something to learn about a track or a car or yourself!

PS: I addressed my mod bug by putting $6,000 into a 1988 Porsche 944. This way, I won't ruin my C32 as a street car by turning it into a great track car!

MRAMG1

Ten four Fifth:

There is ALWAYS something to learn, NO DOUBT ABOUT IT.

I too, do not wish to ruin my little C, just was hoping for a little more gain in the handling aspect, provided that it works

Hey, what did you use for rims? Please don't tell me you bit the bullet and bought another set of AMG's. If I can get some rims, reasonable, I will just slap on a set of R1's.

Thanks fifth!!!

See yeah

PS: I like how you handeled your mod bug

dorikin_86

You can buy a set of street aggressive tires such as the RE01R or Neova to pick up some time.

I think KW makes a decent coilover for the car as well.

Tires + coilovers + alignment should be the fastest way to pick up time and OH...brake pads...the stock pads suck.

AWDman

you have the virus eh...

1. biggest diff comes from you getting to know the car on track...

that said, i think you need the following -a big safety benefit to them as well.

1. r compounds prob net the biggest gain. i've found wear to acceptable for my purposes. my stickest tire hankook z214 c51 compund lasted longer than yoke a048. run 255/40 rear and 245/40 fronts if you can't fit 255 alround.
i'm having my fenders rolled next week will report back on my efforts to fit the R1 in 255 infront. tires like toyo ra1s or MPSC will last longer. R1s seem to be the ticket tho...

2. sway bars front and back. i use h and r.

3. kmac camber bushings- car will steer like a gt3 but be a bit more harsh over potholes.

motul rbf 600 or 660 is a must along with great pads. i brake later than most cars but part of that is due to the ease of the auto tranny.

i tentatively would reccomend brandons larger heat exchanger along with the windshield resevior mod. the c32 suffers from heat soak pretty badly.

my advice is to make whatever changes at once/asap and start running the car in one setup specification....that way you get to learn limits. it sucks making changes. i was on a learning curve and coundnt avoid most of what i had to do.

my c32 has run 18 or 19 track days since 8/05 and none the worse for wear....some bushings got soft right rear shock, picked up replacemnt kit from parts counter for $12:-

rotors should be considered a consumable.....they last 8-12 events.

i'm for tracking the c32.where else can you enjoy the performance? i will cut down on events next year as i will be runnning another vehicle.

last week i was at a porshe club event at lime rock the fast guys were running 1:05+. well i run same times with bald tires and big heat soak! i plan on suprising some folks next year....

dkflipse

Any squeaks or similar noise from the kmac bushing upgrade??

CynCarvin32

Went from a 1:40-1:43 or so to a 1:34 in lap times at willow springs and the car had Carlsson RS kit, H&R bars, RENNtech monolite wheels with r-comp tires 245/275, Stoptech 4 wheel kit with Pagid Black pads front and orange rear, ECU Pulley SL airbox and splitter, massive intercooler upgrade, re-plumed IC core in V of motor, SPG racing shell, polly bushings front and rear, camber set to 2.25 front and 1.9 rear, toe set to 1/16th total toe in in the front and oem in rear (going less makes the car darty under braking), additional camber via washers between spindle and hub.

The 1:40 lap time was done feeling pretty sloppy and out of control but the 1:34 was a safe smooth fast lap you could replicate all day long.

So with serious work you can take a good chunk of time off the given lap time.

CynCarvin32

terribe levels of squeaking and and a terrible ride. This was way the car ended up being sold. With the bushings it was fast and fun (ok tire wear) but without them the car eats tires every 4-6 hrs.

Only do the bushings if you really don't mind the ride being like a lumber wagon.

Plus the bushings fail very frequently. That is a serious pain in the rear.

speedybenz

Now if you had a C43 then We could talk about Penske Shocks and adjustable everything. 1:34min lap time is pretty good. I am going to have to bring my C43/55 down to Willow to see if I could somehow crack that 1:30min barrier for a car.

It was pretty easy to do 1:22mins there on my Superbike.

Jeff

dkflipse

Damn. Glad I asked! Great feedback Cyn

MRAMG1

[QUOTE=CynCarvin32;2442623]terribe levels of squeaking and and a terrible ride. This was way the car ended up being sold. With the bushings it was fast and fun (ok tire wear) but without them the car eats tires every 4-6 hrs.

Only do the bushings if you really don't mind the ride being like a lumber wagon.

Plus the bushings fail very frequently. That is a serious pain in the rear.[/QUOTE

Hey there CynCarvin32:

THANK YOU

I was just at Kmacs website, part #502216K for the front, But I CAN NOT LIVE WITH SQUEAKS ON A DAILY DRIVER.
I know I need more negative camber, atleast on the drivers side at beaverun, but I will find it another way now.

Thanks again for the heads up!!!

See yeah

MRAMG1

Hey thanks again for this TERRIFIC info.

I will do the washer trick, and already have some of those other goodies coming

This was JUST WHAT THE DOCTOR ORDERED FOR MY PERSCRITION my friend

God I love these sites

See yeah

PS: I have been road racing for about 17 years now with many differnt cars, but I am always out for some good info on a new toy. THANKS GUYS

CynCarvin32

If you have questions let me know. SMGC32 and my self can answer all the track questions out there. Always glad to help.

The faces you see when a C32 with no badges and no star on the trunk is glued to the bumper of a lightly moddified 996 TT or a totally upgraded M3 is hilarious. Once set up well the C32 was a real blast. SMG has since gone to a 335i and he put a TCKlyne coil over kit with 500 lb springs and he is about to run the car into a tree in frustration. He really thinks the C32 rode just as terribly as the 335 with 500 lb springs but it never bottomed out and it was more stable and fun at the track.

CynCarvin32

[QUOTE=MRAMG1;2442676]PM me you can get 2 to 2.5 degrees of negative camber out of the car by inserting a washer or two between the spindle and the hub. Shimming it out is a pretty "ghetto" mod but it works. Sticking around 2 degrees should be enough for most driving.

The W203 has a really odd suspension geometry where the caster changes as you turn the wheel left to right. You can see the sturt tower shift fore aft as you turn left right (while still). This is likely done for making the turning circle smaller and to make it have smoother steering at low speed but its a disaster at the track.

It prevents you from being able to use camber plate and it also makes setting the alignment very difficult. At 3 degrees the inside was over heated and the wear was not great and at 1.75 the the outside of the tire was gone in half a day. Around 2.3 you get to the sweet spot but that is for serious all out driving.

zcct04

CynCarvin32,
When you stick the washers in between the strut and the hub, does that change anything else on the suspension that needs to be adjusted? I was thinking tonite about doing that to my M Roadster for autocross weekends, and I'm guessing that it would require a big toe adjustment after shimming. Your experience?

Zeppelin

Yes, your Toe alignment will be way off and needs to be aligned. Other than that the only issue could be tire to strut interference at the top of the tire since it will lean in more with the washers.

rbaker

I agree with most your rec's, except the OE toe in at the rear. IIRC, I reduced my rear toe in to ~1/16" in and the car is still completely stable under braking. However, I don't have your H&R bars or Carlsson RS kit, the springs, dampers & bars are stock C55. The washers up front work great & you can't beat the price. Increasing the front track width does wonders too.

AWDman

with front fender well space being at a premium i see this as a huge negative.

i really like the enhanced feel of the stiffer kmac bushings and my ride quality has not suffered too much. credit to the rennech springs?

my bushings come out today for grease to be applied to the inner face- this is where the squeaking is being created, soft urethane rubbing against the hard urethane as suspension moves. hope it works, if not, i can live with the squeaks.

c32AMG-DTM

But doesn't increasing negative camber increase the clearance between the tire's shoulder and the fender lip? If so, isn't that the area where most people tend to have problems (i.e. rubbing)? Or did I misunderstand what you're getting at...?

AWDman

the crash/camber bolt /washers will tilt the wheel in realtion to the strut tube. there is very little clearance with 245 track tires as it is.... there is a real possiblity that the tire would contact the strut tube. i guess you would have to play around with tire size and wheel offsets. maybe the guys that have done this could comment in more detail.

c32AMG-DTM

Ahhh... thanks - didn't realize this "washer" approach was in addition to 245s up front; I can see how there'd be very little room to work with in that case.