off-season plans/ideas

[dawgscj7]

So after one full local season in SMF with current setup, I finished 2nd overall missing a season championship by 12 points. But after a terrible last event, Im planning changes and improvements for next season.

Current setup:
tein s-techs
jcw struts
h-sport comp rear sway bar
front and rear strut tower bars
215/45r17 direzza star specs
RPF1's 17x7
alta 15%
dt bpv
rear interior removal
1 ball exhaust
intake
hawk HPC

plans:
225/45r17 z214 c71(cost effective)
I.E. race camber plates
w.m.w. 17%
stud conversion(anyone know any for M14?)

ideas(if extra funding is available):
koni yellows
or
megan racing track coil overs(would eliminate the need for above camber plates)

I know a couple of you guys compete regionally and nationally and this where I intend to take this car. Only one or two events for 2012, but hopefully 2013 competing in all regional events.

So I was looking for some feedback on what are necessities for next season, what I should or shouldn't do to make the car more competitive.

main issues:
lack of grip and very large mixes of over and understeer at anytime, I fight to make the car track straight.
more low end acceleration when winding out of longer/slower corners.

Any help would be appreciated and hopefully Ill see some of you guys regionally in 2012!

[Rally]

I know you already know, but camber plates will definitely help you on your first goal and will even help you a bit on your second if grip is hurting your out-of-corner acceleration. Keep those high on the priority list. When i was competing in autocross, camber plates were the best thing I ever did (next to the rear sway bar).

I'm not familiar with the SMF class. Are you allowed to run non-stock tire diameters? Dropping the diameter of the tire will improve your gearing to give you a bit more pep while also cutting down on ride height, sidewall flex, and rotational weight.

[minimusprime]

I'd focus on alignment tbh. some where around 2.5 degrees negative in front and 1.5ish negative in back with toe tailored to your liking (for the track I found that 1/16 in in back and neutral in front was my jam).

IMO I'd forget about the 17% pully. Spinning the SC faster really isn't goign to make your lap times go down imho. For the track I liked to keep it at 15% to keep the waterpump nice and happy and the IAT's down. I don't know what year your car is but if it's an early model with the taller gear box do as rally suggested and get some smaller diameter tires. It will make up for your gearing and tq issues.

Again I'm not sure if your car has an LSD but if it doesn't you should be focusing on that. Without an LSD you won't be able to put much if any corner exit power down on this car.

YMMV but some food for thought along the way.

[iDiaz]

I agree with the camber plate and alignment suggestions. As minimusprime said, you didn't mention whether you have a limited slip or not, though. If you don't have one, get one. If you do have one, I would recommend a little bit of toe-in up front (not much at all), and zero or a little bit of toe-in rear. Toe-in on a car with an LSD does the opposite of what it does on a car without one. It will help pull the car tighter under corner exit acceleration, reducing understeer.

Be careful with too much negative camber up front, as it can hurt corner exit acceleration due to the MINIs unfavorable front MacPherson strut geometry. It'll help the outside tire grip harder, but it'll exaggerate the negative camber effect on the inside tire, shrinking the contact patch. You'll have to experiment to find the right combination of camber, tire pressure, and rear swaybar stiffness. Use a tire pyrometer to measure temperatures across the tread immediately after pulling off, and mark your sidewalls to gauge how far you're rolling onto them.

[glnr13]

Smaller tires will help acceleration immensely. Be sure to play with tire pressures too.

[dawgscj7]

I do have an LSD, and the shorter gear ratio. I already mark and monitor tires temps and pressures. Alignment and grip I think are the answer though I never thought of front toe in, how bad does it scrub the tires? I thought with the 17% pulley I'd get more low-mid range power due to short -medium sizes courses and I could switch back to my 15 for longer "known" venues.

[dawgscj7]

I can find shorter diameter tire for 17's If I sell my rpf1's I wanna drop to 15's

[iDiaz]

Originally Posted by dawgscj7

I can find shorter diameter tire for 17's If I sell my rpf1's I wanna drop to 15's

I wouldn't go shorter than the sidewall you're planning on getting (225/45). Shorter sidewalls are stiffer and will flex less, requiring tighter control over camber than the MINI's front suspension is capable of providing. A bigger sidewall is better on a MINI, since the sidewall flex will help it retain contact across the whole tread face during dynamic camber changes. You'd be better off going to a smaller wheel, for sure.

Front toe-in is how it's set from the factory. You might wanna try neutral front toe, too. Front toe-out probably wouldn't be a good idea on a car with an LSD, but it's useful without an LSD, as it causes the inside tire to scrub harder, improving turn-in.

[Rally]

Originally Posted by iDiaz

I wouldn't go shorter than the sidewall you're planning on getting (225/45). Shorter sidewalls are stiffer and will flex less, requiring tighter control over camber than the MINI's front suspension is capable of providing. A bigger sidewall is better on a MINI, since the sidewall flex will help it retain contact across the whole tread face during dynamic camber changes. You'd be better off going to a smaller wheel, for sure.

You can have the best of both worlds if you drop to 15s. Shorter diameter with plenty of sidewall. Tire selection is probably much better too depending on the width you choose

[dawgscj7]

What kind of camber and toe settings are you guys running?

[iDiaz]

Originally Posted by dawgscj7

What kind of camber and toe settings are you guys running?

I don't have a MINI any more, and when I did, it was an R53 S with no LSD, so my alignment would be a bit different. I've gotten positive feedback from people with LSDs though. For what tire/wheel size do you want suggestions? Taller, softer sidewalls call for more static negative camber, since they're more prone to rolling over onto sidewalls.

[dawgscj7]

I ran 215/45r17 dunlop direzza star specs and they rolled like crazy even with high pressures, i was running 46(hot) in the front and 37(hot) in the rear

Im going to be running hankook ventus z214 c71 in 225/45r17 and i have an lsd

[iDiaz]

Originally Posted by dawgscj7

I ran 215/45r17 dunlop direzza star specs and they rolled like crazy even with high pressures, i was running 46(hot) in the front and 37(hot) in the rear

Im going to be running hankook ventus z214 c71 in 225/45r17 and i have an lsd

Holy crap, dude. 46 front? You need camber plates STAT! It's gonna take some adjusting but I would start with something like this:

Front:
Camber: -2 to -2.5 degrees
Toe: 1/16" toe-in

Rear:
Camber: -1 to -1.5 degrees
Toe: 0 toe to 1/16" toe-in

For the rear, going with less camber and closer to zero toe will make it easier to rotate the car, so you'll have to balance that against the sway bar. For the front, you'll have to experiment with tire temperatures and see what works best. Keep in mind, adding that much negative camber to the front will shift cornering balance away from understeer (possibly towards oversteer), so you'll have to watch your swaybar settings to balance it out. Be extremely careful when you make alignment changes, as they will drastically affect handling, including making your car unstable if you take it too far. Always find a safe place to test.

Also, when you're making alignment changes, it's crucial to only make them incrementally until you understand what those changes do. For example, I would start by getting an alignment and just altering toe. Once you get a feel for what the toe change did, introduce changes to camber and see what those do. Camber mostly helps around tight corners. Toe can affect cornering all around, but it will change performance in different ways depending on what you're doing (speed, braking vs accelerating, etc) due to bushings flexing and changing toe dynamically. For example, toe-out in the front can make the car really sensitive to steering inputs, and can make the car darty under braking, to the point that you're white-knuckling the car a lot in order to keep it in line.

Another consideration is caster, but there really isn't much room to play with that on the MINI without altering the strut towers. Some camber plates will allow caster adjustment, so it's something to consider. The way caster works is it multiplies negative camber as you increase steering input. With lots of positive caster (strut tilted aft at the top), you can gain lots of negative camber with larger steering inputs (like in a tight corner) and better on-center feel, at the expense of higher steering effort. Unfortunately, due to limited space inside the strut tower, and limited camber plate designs, you're usually trading off caster for camber, since leaning the top hat aft (more positive caster) means there's no room to lean the top hat inward (more negative camber). Using lots of positive caster (possibly more than the MINI can achieve) instead of negative camber can help improve straight-line grip, since the contact patch is flatter when there is no steering input.

[dark_S]

+1 to pretty much everything said above.

i'm running zero static camber in the rear (-2.6ish up front) and it's very good. i'd also wager that tire compound is more important than tire size. don't go up in width to go with a less competitive compound. ultimately though, in SMF you should be on Hoosiers not street tires.

camber plates (or coilovers with plates), tires, and practice driving high hp fwd will do you the most good.

[dawgscj7]

so here is where we stand,
new mods:
Bc racing coilovers(r56 springs)
megan header with factory cat welded in
alta exhaust
wmw 17% pulley
cabrio bars
short shifter
15x8 konig wideopens(11.8lbs) et25
225/45r15 hankook z214 c71
and random weight loss

So far im very pleased with how the car handles especially with the heavier rated springs on the coilovers. the only issue im currently having is a little midrange hesitation cominig out of WOT and immediately returning to WOT. needs a better alignment still but very pleased with results.

other mods(still on car):
hawk HPc
rear seat delete
front and rear strut tower bars
26mm hsport rear sway bar on middle setting
CAI
tensioner saver
bushing inserts for engine mounts

old mods(not on car)
alta 15% pulley
one ball exhaust
jcw struts with tein springs
17x7 enkei rpf1 +42
215/45r17 dunlop direzza star spec

New plans(who knows when):
hawk HP+
slotted rotors
sneed speed shop splitter or wyvern splitter
wyvern wing
cage
corbeau fx1 wide
harness
gp intercooler
cams
injectors
rmw tune
strip rest of rear interior
tsw xbrace