Best way to get the power to the ground?

[Logan]

Situation:
relatively high powered FWD car (200ish hp)
Has problems putting power down when the grip isn't there, ie cold track and cold tires. (as shown at the shootout)
playing with pressures doesn't do much, depressing the go fast pedal makes the wheels spin.
With winter coming I'm looking for things to do that can help the car put the power where it's needed. I want to be able to play in the snow too without making ice patches where the tires used to be.
The stock springs are relatively soft, as are the motor mounts.
I also want to be able to compete with some of the faster guys in solo 2 next year, so I'm looking at ways to increase the grip.

Should I change the car or learn to be gentler with the loud pedal?

[Cliffy]

Sounds like you may simply be getting on the gas to aggressively and too early while exiting a turn. If that's not the case, then the mechanical cure would be a posi diff. You didn't mention what kind of tires you're running or how old they are.

-c.

[Chris P]

This is a typical problem with the mazduh speed. Too bad the diff didn't make their list of things to do. Whats with car company's not doing it right! Atleast CRYsler will be putting a diff in the SRT4, perhaps enough racers complained and its gonna need it to be competitive in T2(SCCA Showroom stock) and in DS(SCCA SOLO2).

Their is stuff you can do that may remedy the problem but it won't be easy. Be creative with the rules and the car. Will you be running in stock?

Then again it could just be the happy foot, i haven't driven one so i really don't know about that aspect.

[MiG-29 Foxbat]

Even the AWD guys had a hard time launching there. It was just cold.

[Logan]

The car does have a limited slip.

Being creative within the rules becomes interesting when I don't know exactly what the rules will be next year.

I probably wont run stock (DStock), I'm leaning towards DSS.

[ice/solo racer]

Doug I wouldn't use the shootout as a comparision on handling problems,EVERYONE had a huge lack of grip in those conditions.Did you notice the amount of spins/near spins,more at this one event the entire season combined.The front of my car was pattering badly on the khumo's,competly gone on the 32r's.
Your car does seem to put the power down very well indeed-thats what impressed me the most during the ride along I had with you.You were also the only one able to beat me this season-something must be working well.(cause I'm so good!-yeah right I'm kidding)
But to give a comment to your question,upping the rear spring rate/rear bar rate will keep weight from transfering off the front wheels on acceration and steal grip at the front right when you need it the most.Watching the mazdaspeeds run from the outside they never seem to have anything more than a little understeer,stiffer rear parts should help in both transitions/hairpins and corner exit push.
Just a thought from a rwd guy soon to be a fwd guy(not sure if thats a good thing?)

[Logan]

Tom, you've got more experience playing with spring rates than I do:
If I keep more weight on the front wheels how will that steal grip?

[Marsh]

Logan think of it this way. When you step on the gas exiting a turn the front inside wheel lifts and looses grip. Stiffening the rear end will keep that tire planted and give you grip coming off the corner. It will also make the car understeer less.

[ice/solo racer]

Doug what I meant by stealing grip at the front is on the stock rates the front end is lightened when you get on the throttle,so stiffening the rear helps in reducing this.Also a bigger rear bar aids in corner turn in and at corner exit by transfering some weight onto the inside front.Unfortunately it also transfers weight onto the outside front,so a balance of spring and bar rates need to be found.
Just replacing the rear bar alone doesn't effect the ride on the street unless a bump is hit with only 1 rear wheel,while the ride stiffness obviously increases with an increase in spring rate.
For a dual purpose car all this starts to become a matter of how much you can live with on a daily basis versus how competitive you wish to be on sunday.
The easiest way would to be a set of coilovers with adjustable dampening,spring rates can be changed fairly easily to find the balance you like,an adjustable rear bar is also important.Without an adjustable rear bar the car could easily be dangerous at highway speeds if an emergency situation is encountered,so you could set it soft for daily driving and full hard for competition(or whatever worked best).
Sounds like your heading down the same road I did awhile ago,keep using the street car or go a little beyond that-I don't intend to run a dual purpose car ever again simply because of the chassis tuning needed to make the car(really)great on sundays starts to take the joy out of the monday to saturday.

[Logan]

Does anyone know where the "comfortable" spring rates stop and the "performance" spring rates begin? Somewhere around 200lbs?
There are a few different coilover setups available for my car, one comes with 275lb front springs and 325lb rears, which I think will make the car uncomfortable and skittish at highway speeds.
If I have an adjustable rear bar (I do now) would setting it to full soft give me back more "security" at highway speed?

I wish I had all the options you Honda guys have!

[J.C.]

That's a personal feel issue. Also it will vary depending on if they are progressive or linear.

Speed race series type R is 2000lbs spring rate, now I would consider that a little on the harsh side.

[Chris P]

yes, my mistake with the diff, i was thinking of something else :eek:



"skittish at highway speeds" ??
"back more "security" at highway speed"

tell me more :confused:

[ice/solo racer]

Doug those rates wouldn't be bad on the street,I assume those are a linear rate spring as its on a coilover.You don't want a progressive rate spring-simply to soft initially and takes to much compression before they stiffen enough,for steering response linear rates is best.Yes setting the sway bar to its softest setting will reduce oversteer/increase understeer and makes it a little more predictable.My 1st gen crx si that I built up years ago didn't have an adjustable rear bar and was actually very loose at triple digit speeds,even pushing hard on onramps had me on my toes more than once.You should seen the looks I'd get after the ass breaks loose and you drift(bad word)the last half of the ramp with the throttle buried:cool:
I know some of the hada guys run spring rates that I thought would be nuts on the street,they think its fine.Hanif has nearly 800lb springs in the rear of his civic and the last I heard Pat Yorke was up to 1000lbs and a very big rear out back-not sure whats up front however.

[Marsh]

Woh, hold the phone. You can NOT compare spring rates between cars. different mounting positions and strut angels mean that the same spring can result in very different wheel rates from car to car. On a Subaru 200lb/in is moderately stiff. On my car it would be stock. I'm running ~650 (12 kg/mm) up front and I don't mind it on the street any more than my 425's I had. But on your car 650 might be rattling your fillings out. What's important is WHEEL RATE, not spring rate.

If you can't find a website with people that have experience with your car, then just call Ground Control and talk to them. But whatever you do get linear rate springs!

[ice/solo racer]

Sorry Marsh,forgot to mention camparable wheel rates as I'm thinking that the mazda front strut will/should be located very close to that of most any other smaller car with strut front suspensions.Its the rear that tends to be the most different between different vehicle makers.