FWD Autocross setup questions

Ok, so I have a few questions about basic FWD setup. I read the article in last months mag about setting up a FWD, I just wanted to pick the brains of all you experienced autocrossers.

I'm a total newb, went to my first auto-x last fall, and I'm driving a less than perfect car. I've got an automatic '95 Maxima. I love this car, it's been with me for 6 years, and I ain't getting rid of it. I also have nowhere to put a 3rd car that may be a little more fun, so this is what I'm autocrossing. I don't have the time or money to do a whole lot of events, so honestly if I get to 2 or 3 this year I will be doing well.

The car has some lowering springs on it (more aesthetic than anything), and some 17" wheels with 225/50-17's on them. Other than that it's bone stock.

I've been thinking about what the article said about loosening up the rear end, and I was wondering if my idea is stupid or awesome. Would it be ridiculous to run a wider wheel up front with some slicks, and keep some regular-joe tires in the rear? I've seen FWD cars in the mag with wider wheels up front, I just though I could take it a step further with the slicks. I'd like to get a rear sway bar too.

Now, I'm not a total moron-I realize seat time is the easiest way to get better. I don't really care what class I get put in, I'm really only competing against my buddies since I will probably only get out to a few events. I can get used slicks from usdrrt, used wheels from Craigslist, and a sway bar from ebay. These seem like the simplest and cheapest upgrades I can make that will actually do anything.

Ideas? Feedback? Snide remarks?

Work on the "nut behind the wheel". Seriously, just drive the car as-is for a handful of events...work on driving smoothly to where you're not driving too fast on the slow bits...and consequently too slow on the fast bits. Its all about exit speed off the corners...which will never come if you're over-driving the front end of the corner. A fast driver in a slow car will beat a slow driver in a fast car. Every time.

Work on being a "fast driver"...then worry about the car.

^

What FSP_ZX2 said........

Work on your driving with more seat time and get experienced, fast FWD competitors to ride along. Have them drive your car while you sit in the passenger seat. You have much to learn, young jedi.

At this point, you shouldn't do anything to the car other than adjusting the pressure in your tires.

oldsaw wrote: At this point, you shouldn't do anything to the car other than adjusting the pressure in your tires.

Unless it's broke or wore out. No reason trying to get better when you are throttled with junk.

The setup you're talking about would shift the handling balance massively towards oversteer, does the car understeer that severely right now? Staggered wheels should be your last resort, first lighten the rear end and get a rear sway bar, then try stiffer springs on the rear, then try more negative camber up front, then try overinflating the rear tires. Once you get a decent handling balance you'll want as much grip as you can get on both ends.

What he said. The problem with FWD is that it understeers under power and oversteers under deceleraton. The main problem with most is the strut suspension. As the car rolls the camber goes the wrong way. With a little work, a FWD car can be made to handle quite well and steerable with the throttle.

But as everyone said, In an autocross, the driver is more important than the car. Mostly.

While it's hard to argue that seat time and driver development is really the best way to go faster, there are still some things I would and wouldn't consider modifying on the OP's car.

Slicks up front - seems like overkill and a good way to have a really weirdly balanced car. That said, I haven't tried it and it might be fun, if not as fast as you might think. My biggest gripe though, is that this is mod-money spent on something that you'll only use 2-3 times a year.

If-it-were-me, I'd focus on mods that will also benefit the other 49-50 weeks a year since this is you daily. A rear sway is relatively inexpensive and won't affect ride comfort that much, if at all. I say go for it if it makes those autox weekends more fun.

The other mod I'd consider is dampers. If you're running stock dampers on lowering springs then they're probably not that well matched. A good set of Bilsteins or Konis will make the car more enjoyable anywhere you go, imho.

sethmeister4 wrote: Ok, so I have a few questions about basic FWD setup. I read the article in last months mag about setting up a FWD, I just wanted to pick the brains of all you experienced autocrossers. I'm a total newb, went to my first auto-x last fall, and I'm driving a less than perfect car. I've got an automatic '95 Maxima. I love this car, it's been with me for 6 years, and I ain't getting rid of it. I also have nowhere to put a 3rd car that may be a little more fun, so this is what I'm autocrossing. I don't have the time or money to do a whole lot of events, so honestly if I get to 2 or 3 this year I will be doing well. The car has some lowering springs on it (more aesthetic than anything), and some 17" wheels with 225/50-17's on them. Other than that it's bone stock. I've been thinking about what the article said about loosening up the rear end, and I was wondering if my idea is stupid or awesome. Would it be ridiculous to run a wider wheel up front with some slicks, and keep some regular-joe tires in the rear? I've seen FWD cars in the mag with wider wheels up front, I just though I could take it a step further with the slicks. I'd like to get a rear sway bar too. Now, I'm not a total moron-I realize seat time is the easiest way to get better. I don't really care what class I get put in, I'm really only competing against my buddies since I will probably only get out to a few events. I can get used slicks from usdrrt, used wheels from Craigslist, and a sway bar from ebay. These seem like the simplest and cheapest upgrades I can make that will actually do anything. Ideas? Feedback? Snide remarks?

You are trying to beat a dead horse... Slicks do 1 thing very well, and thats cover up your driving mistakes...Slicks on the front and streets on the rear can have some really odd affects on how the car handles... It could be good, or it could become a nightmare with really bad snap over steer problems...

I would work towards improving the nut behind the wheel the most... Make friends out there and connections... Hopefully find someone you can set up a co-driving agreement with... You'll get more out of the sport this way...

It is a heavy, relatively powerful car. That's giving you some advantages and disadvantages, of course.

As others have said, only adjust air pressures right now. For a car like that, I would suggest starting around 40-42 psi in all the tires. In front, that will help them not roll over under cornering. In the rear, which is less heavily loaded, it will reduce grip a little. If you notice rub marks way up the sidewall in front, try stepping up to 44 or 46 psi.

In stock form, your biggest challenge will be learning to drive to the ability of the car. Braking too late and making harsh steering inputs will definitely bring out the worst in the car. Brake early, brake hard in a straight line, and ease up on the brakes as you turn in for each corner. This will slow the car and transfer weight forward, without overwhelming the front tires. Keeping some weight up front (by the reduced braking, also called "trail braking") will help the turn-in, and at the same time, the reduced rear load will help the car rotate.

The key is to not overdrive. Flogging the car will not make it faster, it will just make it plow more and scrub off speed in the corners. Make prompt but smooth turn ins, then transition from brakes to gas as the chassis gets settled. For the entire second half of the turn, adjust your path with the throttle, not the steering wheel. If the car understeers and goes wide, lift your foot off the gas until it tucks back in line. Steering harder will just make the front tires crab more, costing you speed. This is a hard lesson to remember in the heat of the moment, and I for one am still working on it.

After several events in completely stock form - and take instructors on as many runs as you can - you might want to consider getting an alignment. In order to help the front tires stay square on the ground during turns, you want negative camber up front. I don't know the details of the Max's front end configuration, but on my daily, there where some locating pins at the top of the strut that could be removed to allow a little extra negative camber adjustment. Up to about -2 degrees camber will not really affect tire wear (and will probably actually improve it, IMHO) as long as the toe is approximately zero. This will help the car rotate in corners as well. If you can't do this, then keep making moderate adjustments to tire pressures to get the balance as close as you can. You may need to run substantially higher or lower pressures in the rear to get the effect you want.

Another option is to add a heavier swaybar at one end or the other, but I would not make this change until you have at least a half dozen events and lots of instructor runs under your belt. Do some research and find out which is more effective for the Maxima: typically in FWD cars, you want to stiffen the rear swaybar (or anti-roll bar, technically), which reduces traction relative to the front. However, in some cars, it is more effective to stiffen the FRONT bar, because a flatter cornering stance yields better traction due to the front tires meeting the pavement more effectively. This is especially true on cars that are very limited in how much negative camber can be achieved.

Hope this helps, and welcome to the adventure! Always remember two things: 1) you can never have too much instruction, and 2) this is supposed to be fun.

With that car, and its current modification level, you might as well just run ST classes and get better at driving it. Just air pressures can make a difference between under and oversteer

Then save your money in the event you want to continue doing it in a more competitive car.

One thing I will suggest is some method of adding camber in front, be it crash bolts or whatever. In theory it should help grip but that's not really what's important. What 1.5 degrees of camber will do is dramatically increase the life of your tires outside edge while auto crossing while not decreasing their life on the street. Learning to set your own camber and toe is a very worthwhile project. It's cheap and useful and and a great skill to have.

Thanks for all the great advice guys! A few things have stuck out to me so far in what has been said:

Yes, I know that improving my driving is the first key. I knew that was going to be half of the answers I got, and I totally agree. I just know that with my other responsibilities and commitments, I will only make it to a couple events this year, so I want to make the most of them. And most of all I want to beat my coworker. :-)

The Maxima is a MacPherson strut front suspension, and is in the 2900-3k weight range. I have stock replacement KYB struts with TEIN springs. I know I should get better struts, but I am kinda cheap (or thrifty, depending on how you look at it) and these were still good, so I just left them. When they die I will put something better on. The rear suspension is struts too, and uses Nissan's twist beam axle thing-no independent here, unfortunately. Oh, and no Maximas of this generation came with a rear sway bar, so I only have a front one (18mm, I think).

I figured my slicks-in-the-front-only idea was a bad one, I just had to ask. It probably would be fun, though.

So, I think what I will consider in mods is possibly a rear sway bar, and possibly some camber bolts for the front. I think I can get some that are adjustable up to -2 degrees. I got great advice from some experienced guys at the auto-x I went to last fall, so I am looking forward to driving with them again (Old Dominion Region of SCCA). Oh, and I ran in STC last time, although I think I just got put into the Novice class.

I am a relatively experienced technician, so I know and understand camber, caster, alignment settings, etc., and I have access to an alignment rack whenever. The only thing adjustable on this car is front toe, unless I get camber bolts for the front. The rear is solid axle, so no adjustments there.

Here's a link to a video that my buddy took at the autocross I went to last year.
Maxima autocross

In reply to Duke:

I want to say a specific thanks to Duke-I think I'll print out your advice and memorize it! Thanks for taking the time to help!

With SCCA, you'll still run against the STC class, Being branded a "Novice" just allows you to compete across pax with other "Novices" for a end of day trophy.

I airquote novice due to a guy local to me who would attend every novice meeting, ask the dumbest questions, then go out and run faster than 95% of people.

sethmeister4 wrote: In reply to Duke: I want to say a specific thanks to Duke-I think I'll print out your advice and memorize it! Thanks for taking the time to help!

My pleasure. I'm not that fast in the grand scheme of things, but I'm happy to share what I've learned.

Found some front camber bolts that adjust from -2.5 to +2.5. Raybestos from Rock Auto-might pick those up at some point, I'm overdue for an alignment anyway. Working on installing my poly bushings (I've had these laying around for a couple years) in the front LCA's. Kind of a pain, but way cheaper than buying new control arms-got the whole Energy Susp. kit for like $30, just need to buy some new ball joints to press in.

Sounds good! I would have as much static negative camber as you can get to be equal on both sides, preferably with you in the driver's seat, if they will let you sit there during the alignment.

The shop will tell you your front tires will wear out faster and maybe make you waive a warranty on the alignment. In my experience, running -2.0 to -2.5 static negative camber actually improved the wear pattern on the front tires, and I got better life out of them.

My personal opinion is that starting out with a car like yours will make you a better driver in the end. I feel my first autoX car (1993 dodge dynasty) was a big part of why i had fun and got semi-fast. It had low-ish limits but was fast enough in a straight line to make you feel like you were getting somewhere if you floored it, and it definitely taught you ALL ABOUT weight transfer and its effects because it was so exaggerated. The fact that it was a VERY lowly family sedan made my times in it seem even better than they were, which added to the fun immensely vs me going slow-ish in a more capable car. My honest opinion is that for new racers, it's better to be in a car that gives you time to think. Ive seen people show up to their first autocross in an evo or a high-power rwd and have a lot more frustration than fun because the car gets away from you so fast, and makes you look bad for performing so far below the expectations it sets for both the driver and the spectators.

Let me tell you, it wasn't that slow, even stock, even looking like that. Even today a good driver can show up to an event in a car just like that one, or yours, and pax in the top 3rd easily (excepting any mechanical issues or really poor tires). That's one thing you have to drill yourself on: dont blame the car. You can always drive better, and a fast driver in a slow car will do really well at almost any local event.

A lot of it is universal, or just intuitive based on the various basic types of cars, so that once you know it, you can go pretty fast in anything wihout a whole lot of learning curve. Of all the people ive co-driven with, there was only one guy i didnt beat in his own car, and that was by hundredths. The last thing i co-drove was an XP turbo crx that was a handful to the extreme, but i was still within a few seconds of the fastest cars on course, even with no experience in a car like that (something like 5 seconds faster than the owner on a high-30s sec course). It all comes down to things you can learn in any car, so focus on learning more than on the car!

Duke wrote: Sounds good! I would have as much static negative camber as you can get to be equal on both sides, preferably with you in the driver's seat, if they will let you sit there during the alignment. The shop will tell you your front tires will wear out faster and maybe make you waive a warranty on the alignment. In my experience, running -2.0 to -2.5 static negative camber actually *improved* the wear pattern on the front tires, and I got better life out of them.

I'm a mechanic, so I'll be doing the alignment myself-maybe I can have a buddy sit in the car for me. And I'm not too worried about tire wear; I can usually get some decent used ones that some customer thinks need replacing, and there are plenty of used tire places around me. (I spent exactly nothing on the tires that are on the car now)

In case you're curious, here are the results from the autocross I went to last fall. Look at the results from Event 6, 9/2/12. I think I could have done worse than 38th in PAX on my first time out.

Thanks for all the continued advice fellas!

Besure to reset the toe after the camber change.

There are ways to stiffen the twist beam. Get creative.

In reply to iceracer:

Such as? I'd like to get a sway bar to throw on back there, but if there are other cheap ways I'm all ears!