Autocrossing and a modified MS3...help!!

[AutoXRacer]

I just attended my 3rd autocross with my MS3 this weekend. Though it was fun, I was very frustrated because stock MS3s were leaving me in the dust by 2 or more seconds... (sad) (bang)

My issue was traction!!!! (burnout)

The guys were telling me I was smoking my tires from corner to corner...the whole course (it wasn't clouds of smoke, more like hazing). That was fun!!!

But there was nothing I could do. I'd roll on the throttle and tires would break loose at any speed and any throttle position. When I tried to control wheel spin, my times suffered. The only way I got my best times was at WOT letting the tires spin.

Those of you that have autocrossed/raced your MS3 longer than I have, do you have any suggestions/recommendations?

I know the tires I'm running don't help. I am running RX-8 (18x8) wheels with the stock bridgestone 225/45/18 with little life left.

I am planning on purchasing 225/40/18 Kumho MXs and if these are no longer available on sale; I'll go with Falken Azenis; both these tires are very comparable.

I am also thinking about stiffer springs to reduce weight transfer to the rear...but there are only a couple of vendors for springs (Mazdaspeed and Cobb) and I don't know which is a better match for the stock shocks/struts, spring rate, harshness, etc... But that will be for later mid-year or so...

Thanks for the help guys!! (2thumbs)

My intent for this post is primarily more along the lines of driving technique/inputs. Secondly, modifying the car to reduce undesirable handling characteristics.

 

[jbiird317]

first thing I would do is get some new tires, sounds like youve got that one covered tho. Secondly i would look to stiffen the suspension as a whole, not just the springs. A beefier ARB in front and rear, stiffer springs, and if that still doesnt do it, a chassis brace in the front and rear should help. Im not really that into autoX, but I know that a stiffer suspension will help with your distribution of power through the turns.

do you have the stock springs on now? There are much better options out there. If you are not looking for a significant drop, the mazdaspeed, cobb, or H&R springs would be good. The roadmagnet springs I have lower the car more but are a bit stiffer. Ive also heard very good things about the H&R coilovers.

 

[SwampAss]

sometimes a psi or 2 can mean all the difference.



tire psi

 

[jbiird317]

sometimes a psi or 2 can mean all the difference.



tire psi

good advice, and free! (well maybe $0.75 at the gas station)

 

[AutoXRacer]

Yeah, my tire pressures were 36F and 34R (2 PSI higher than stock)... I don't really bump them up like other people in the 40 PSI range. I think thats too much.

I adjust my PSI so that I have even wear across the thread.

Last months autocross I was only 0.7 seconds away from the fastest stock MS3 (it was my first time racing the MS3); I was unfamiliar with the car and its capabilities still; thats my excuse (lol2). Though I don't remember having excessive traction issues. The only change I've done since then, is a BOV/BPV which increased my boost by 1 PSI and peaks 2-3 PSI more.

I'll try the tires first and see what kind of improvement that is... Then springs, sways, and whatever else might follow...

Are Mazdaspeed springs a vast improvement over stock? I assume we have Mazdaspeed springs (stage 1 - stock) and upgraded ones are a step higher? How do the Cobb compare?

I don't know about coilovers... I've read a few negative threads on them. I've always wanted a sweet coilover system though...

 

[Sacrilicious]

i'm a big fan of the cobb springs... they definitely gave an all-around performance boost for me (steering response, cornering, wheel hop, etc). since i haven't tried the mazdaspeed springs, i cannot give a direct comparison, but i DO like the fact that the cobb springs shift more stiffness to the rear than the front (+15%/+25% vs +30%/+30% on the ms springs). this should theoretically help induce a bit more oversteer and shift launch weight a bit more to the front. the other added bonus is that it should also give a bit more civilized ride than the ms springs over normal roads.

be careful about coilovers, though. i know for a fact that they will have a HUGE effect on ride comfort. at that point, you're gonna have to decide on how much you are willing to sacrifice on your DD for the autox improvement. i, personally, have no desire to do it...

 

[Bochet]

Tires, both quality and PSI. Sounds like you've got the quality under control.

For PSI (you may be well aware of this trick) fill em up to recommended PSI. Use sidewalk chalk or soap to rub on the wall of your tire. When you're running the course, if your tires are underinflated, the car will ride on it's sidewall too much and rub off the chalk/soap. This will allow you to dial in the pressure of the tires to your liking.

 

[AutoXRacer]

(+15%/+25% vs +30%/+30% on the ms springs)

So you think the MS springs are rough for DD with their 30% increased firmness?

Did your Cobbs come with the camber links; did you install them?

I like the price of the MS Spring Kit that includes 4 springs and 2 camber links. (scratch)

 

[subiechic]

i'm surprised that no one has said that with driver ability can be a big factor in the time difference.

Albiet, tires and springs will help, but if you are racing against a stock MS3, and this is your 3rd time - i would invest in more run time to get the feel of your car down first.

once comfortable and knowledgable with stock handling, then I'd proceed with tires/springs/other mods... If the stock people are truely beating you still, i'd ask them how long they have been racing the MS3 and overall.

just my two cents -take it for what it's worth.

Steph

 

[Craighjr]

I agree driver mod is needed. I'm not a great driver, and I don't believe my mods SHOULD make me faster then a better driver in a comprable stock car.

 

[Mocoso]

Yeah, my tire pressures were 36F and 34R (2 PSI higher than stock)... I don't really bump them up like other people in the 40 PSI range. I think thats too much.

...

I think your combination of worn out tires and low tire pressure are much more to blame than springs.... 36/34 is close to normal driving pressure .... try 40 specially in autocross where you spend most of the time with the wheel turned... your most likely riding on the sidewalls and hence your traction issue....

 

[AutoXRacer]

i'm surprised that no one has said that with driver ability can be a big factor in the time difference.

Albiet, tires and springs will help, but if you are racing against a stock MS3, and this is your 3rd time - i would invest in more run time to get the feel of your car down first.

once comfortable and knowledgable with stock handling, then I'd proceed with tires/springs/other mods... If the stock people are truely beating you still, i'd ask them how long they have been racing the MS3 and overall.

just my two cents -take it for what it's worth.

Steph

I've been racing for over 5 years now...its was just my 3rd time with the MS3. Like I said, previous races were close: 0.7 seconds and that was my first time autocrossing the MS3. Since then, I've only installed a BOV/BPV and I no longer have traction what so ever... I don't credit the BOV/BPV for it souly...but I don't recall having that hard of a time hooking up. I know the weather was warmer previously too. This weekend, the temperatures were 15* degrees cooler, but I don't think it matters much with street tires.

Definitely driver mod helps...and I need more seat time with the throttle.
But as far as driving abilities, the stock MS3s drivers don't have much on me.

 

[AutoXRacer]

I think your combination of worn out tires and low tire pressure are much more to blame than springs.... 36/34 is close to normal driving pressure .... try 40 specially in autocross where you spend most of the time with the wheel turned... your most likely riding on the sidewalls and hence your traction issue....

I didn't have issues with traction when turning...well slightly...tires screamed.
Main issue was going in a straight line coming out of a corner...

No, I had a nice square wear pattern on the tread...a couple of fellow autocrossers had thought the same thing. I just think going 40 PSI will hinder traction in straight and turning conditions. Wouldn't it round out the contact patch?

I usually set my tires to 36/34 and adjust as needed to use the full tread. If I see any slight wear/scrub on the edge of the tread/sidewall, I bump up my pressures. I also feel the car to see if it feels loose and/or understeers excessively due to too much pressure...

 

[Jeff@Tri-Point]

It sounds like your main problem is the tires. Even on a good street tire that is dedicated to autocross like the Yokohama Advan AD07 or the Bridgestone RE-01R, I've noticed a huge decrease in grip after 100 autocross runs. Also the strut suspension has the poorest camber curve, so it would be good to test higher tire pressures (40+) so that it might reduce the amount of roll over.

In my opinnion I think you would be hurting yourself if you went with a standard lowering spring like H&R, Eibach and etc. Having a 30% stiffer spring doesn't justify the amount of wheel travel that is lost. You are going to bottom out sooner and reduce the weight transfer to be able to rotate the car... Thus ending up with a car that pushes even more.

 

[AutoXRacer]

I'm pretty happy with the stock suspesion with the exception of the following:-during hard accelerations, the front end lifts like crazy!!-while traveling at high speed, the car feels very spongey/bouncey.Other than that, I can live with everything else.

 

[Sacrilicious]

So you think the MS springs are rough for DD with their 30% increased firmness?

Did your Cobbs come with the camber links; did you install them?

I like the price of the MS Spring Kit that includes 4 springs and 2 camber links. (scratch)

ya, i've read that MS springs are rougher for DD than the cobbs, but i have no personal experience.

my cobbs did not come with camber links, but i do know for a fact that they are not needed. i just got an alignment at my dealership, and everything is definitely very close to stock. imo, mazda recommends the links just to make more moola offa you...=/

 

[enganear]

I autoxed for 30+ years before giving it up for combat robots. I sincerely doubt that you need any mods to your suspension to be faster. The low speeds of most autox events demand suspension compliance more than stiffness and the stock suspension is very good in this respect. I have seen many track cars that were very poor performers on an autox course because of their high spring and roll stiffness and high damping that worked so well at the track. You may need to drive slower to go faster. Brake before turns, never use the steering wheel to scrub off speed. Are you using the traction control or turning it off? I sounds like you need some restraint, either passive or active.

Don't try to "bolt-on" or "buy" more speed until you have progressed as a driver. It is an extremely technical sport. Tires make 4 times the difference of any other mod and this is the only thing you should be spending more money for, IMHO.
-enganear

 

[Sacrilicious]

wooo...i didn't realize that springs could be a potentially detrimental mode for autox! (eek2) i always figured what was good for the track with be good for autox, but looks like i missed on that one!

 

[Craighjr]

I would bet that those camber links help keep more than you think. Mazdaspeed parts are well thought out and I am sure they do more than drain your wallet. As for the cars your racing against, are you sure they didn't switch to race rubber to create the time defficit your seeing. It really sounds like your on a poor tire choice.

 

[AutoXRacer]

I autoxed for 30+ years before giving it up for combat robots. I sincerely doubt that you need any mods to your suspension to be faster. The low speeds of most autox events demand suspension compliance more than stiffness and the stock suspension is very good in this respect. I have seen many track cars that were very poor performers on an autox course because of their high spring and roll stiffness and high damping that worked so well at the track. You may need to drive slower to go faster. Brake before turns, never use the steering wheel to scrub off speed. Are you using the traction control or turning it off? I sounds like you need some restraint, either passive or active.

Don't try to "bolt-on" or "buy" more speed until you have progressed as a driver. It is an extremely technical sport. Tires make 4 times the difference of any other mod and this is the only thing you should be spending more money for, IMHO.
-enganear

I disable the traction control and leave the dynamic stability control on. The reason I leave DSC on is becuase the car feels a lot more stable and in control in the turns. I tried running with the traction control on and it messed me up in the corners...

The mods I made to the car were not intended for autocrossing. I just have an uncontrolable addiciton with modifying cars... (lol2)

And I think this is where my problem is stemming from. The stock MS3s are running quicker due to not having traction issues. I see the guys launching nice and smooth with a slight chirp of 2nd shift, but then during WOT, no wheel spin. They just have what I describle as slight wheel spin...during corners, coming out of a corner, and slalomn. And on the straights its nice and clean...you can hear the engine roar without tire spinage. Oh btw, they were all running stock rubber...

I on the other hand slightly tap the throttle in any portion of the course...even straight aways and its just spinning like if I was on ice; even part throttle. (bang)

I guess I'll find out when I get new tires...

I was hoping there was a secret for driving MS3s that I didn't know of... (lol2)