I am not especially familiar with the SCCA rules, but assuming I am in BSP and assuming I love to modify my car just for the hell of it, what other tweaks or parts do you guys recommend for the class given my current list of modifications? I noticed that water injection (meth too?) kits seemed legal as well as different intake manifolds. AFAIK Rcomps are no penalty in the class as well. Any other tidbits im missing? Thanks!

 

You can run water injection but not meth. Make sure you have a stock BOV or that puts you in SM.

 

The splitter is likely a problem too...

 

From the 2009 Solo Rules for SP:

I. Spoilers/splitters and cosmetic trim pieces are permitted. Side
skirts may not be used. Spoilers/splitters must comply with the
following subsections. The intent of this allowance is to accommodate
commonly available appearance kits, and replicas
85
thereof, which have no significant aerodynamic function at Solo
speeds.
1. A spoiler/splitter may be added to the front of the car below
the bumper. It may not extend rearward beyond the front
most part of the front wheel well openings, and may not
block normal grille or other openings, or obstruct lights.
Splitters may not protrude beyond the bumper. Openings
may not be used for the purpose of ducting air to the radiator
or oil cooler, but they may allow air to flow through a permitted
oil cooler provided no ducting is used. The spoiler may
not function as a wing.

Besides the fact that the splitter likely has zero effect at AutoX speeds meaning it is legal, I do not believe it protrudes past the bumper, and if it does, you'd have to whip out the tape measure. I am thinking I am still legal in BSP. Let me know what you think goofy.

I do have the stock BOV. The thing is quite loud already, I have little clue why the ricers need anything more than that as is. Now if I was running 30psi on race gas...

Are water injection gains worth the price of admission and the deionized water fillups or whatever they require? I know nothing about water injection... though Chi winters mean I would have to retune in winter without it Im guessing.

Are there restrictions to fuel type in Solo? I didnt see references to fuel in the Street Prepped catagory, maybe I missed it though. e85 seems like a big advantage on power.

Let me know what else you guys think!

 

No fuel restrictions in SP. I'd skip the water injection... just another thing to break, freeze up, etc. I'm against meth for the same reason though too.

Re: the splitter -- IMO, the rule basically takes away all front splitters because the Evo's "bumper" doesn't protrude enough to actually let the splitter stick out very much at all (like you said, you'd have to take a straightedge out). Personally I'd like to have one for looks, but everyone I know with one that autocrosses has broken it from hitting cones/scuffing on the track surface. And I do personally think that they will help you out, even at "autocross" speeds (I've hit 80+mph at an autocross, I'd think a splitter would help in chicanes at those speeds).

 

So your thoughts are that the splitter alone will bump me out of BSP? I did it soley to get rid of that terrible undertray... Do you know the APR piece I have? I can't imagine that even at 80mph it would make a huge difference.

BTW I have absolutely abused this APR piece and it has held up wonderfully. I have secured it with larger washers and more bolts than from factory, it isnt going anywhere from cones, wind, ground or otherwise.

 

Let's back up a little. You just had your first autocross and are looking to find ways to make your car go faster. If I were you, I would keep the car as it is for a while and learn to drive it consistently fast. Seat time. Seat time. Seat time. You'll get a lot faster a lot sooner by focusing on your driving than you will be adding 50 hp. If you need to spend money on something I have two suggestions:

1) EvoSchool. Dollar for dollar, probably the single best investment I've made in my car.
2) Good restraints. A good 4 point harness can do wonders for your stability and feel of the car.

 

I have had three seasons of track days (probably 15 in total). I am new to Autocross, not new to driving, please dont give me the condescending "seat time talk". Track days are considerably more expensive and cause more wear to the car than an AutoX. I had a lot of fun Autocrossing and with some more experience, will likely find a higher fun to dollar ratio than track days. I am asking what is allowed in the class and what will make my car faster. The AutoX season has probably a month and a half maybe two months left in it, then I start to throw new goodies on my car because I can and I enjoy working on it. I want to modify and stay legal in a class in which the Evo is consistently competitive.

Harness's are a dangerous idea in a car without a roll bar or cage. If you roll the car with a restraint, there is a high likelihood of a broken neck or death because the restraint does not allow for your body to be pushed out of the way. This false safety has been discussed both on here and a number of other forums. I have a harness in my Cobra with a roll bar and it certainly provides for a more secure drive, but until I cage my car (which may happen sooner rather than later) a harness setup is more dangerous than a standard 3 point belt.

 

No worries. I was just trying to help out someone who seemed new to AutoX. I didn't mean to come across as condescending.

Regarding harnesses: I had in mind the DOT approved Rallye-4 Harness by Schroth. Link. It is made to prevent the very sort of injuries you speak of.

Technical suggestions:
1) Tires (Hoosier A6)
2) Higher spring rates (and dampers that can handle them). 7K/9K is relatively low for serious AutoX cars.
3) The rear diff can be changed. Thread

 

Despite me snapping back, I do appreciate the assistance. I am just well aware of how the "experienced" members of this board will treat the uninformed and I didnt want to get into the seat time debate.

That harness is interesting, however, it addresses issues of submarining in a four point but not the rollover issues. Just to clarify what point I was making, the restriction from submarining is what can cause neck breakage or death in the event of a rollover without a hoop as well as the lack of lateral allowances found in a 3 point to move you out of the way of the imploding roof. I am 6'4" and roof space is at a premium . I really would like a harness, but I think the only truly safe way is to get a hoop or cage installed (I would love to know a good shop that would do one for an Evo in the Chicago area if anyone knows).

I am looking for A6's but they are expensive (~$1200 a set). I would like a 265 in 17 or 18 as I would buy another set of rims regardless to mount them. The price difference seems small between 17s and 18s unlike most tires, around 20 a tire. What kind of life can you expect from them? i.e. how many events at 5-6 runs each day? I have a buddy that can get 60% life RComps for 75-90$ a piece... might go that route.

I knew my rates were not all that high but in my first event, I felt the back end "skittering" for lack of a better word around some lumpy medium speed corners. My first thought was too stiff, what do you think the stepping is from?

I would think diff work is pricey, is it really worth it?

 

I think the undertray might be required technically for SP. I get mixed up on the ST and SP rules though...

You can argue the rules all you want, but really unless the people in your local region are douches (or you start winning a LOT), no one's likely to say anything to you.

A6's new are a terrible value IMO. Buy used ones for $40-100 each and move on. The size to have is 285/30/18 on BSP Evos, but fitting those under the stock fenders on a VIII/IX is a tough proposition.

Your best upgrade right now bank for the buck? Sway bars. Front and rear. I'd run street tire too. Changing tires is becoming a big enough PITA I'm thinking of running in the local PAX tire class next year. It's to the point where I dread waking up the extra 30 minutes early...

ETA: RE the harnesses.

You're not likely to roll in autocross and you won't be using them on the street, so your arguments are not very good. For track days your arguments hold a bit more water. One of the local guys here uses a piece of innertube jammed into the clasp to add friction on the belt in order to act as a cheap CG lock.

 

I'm a street tire guy, but I've heard somewhere in the ballpark of 80 runs for new A6's on an Evo. Rotate and flip regularly. YMMV
Play with your shocks (they adjust right?) and tire pressures next time out. I doubt it's from running too high a spring rate though. Even for STU, I'd probably go ~50% higher front and rear and for BSP you have a lot more grip to manage. Or, as was suggested, throw some sway bars on there. Have fun changing the front though.
Sure, if you're building an all out car TODAY and want to go to Nationals next year. But at this point? No. Get more seat time. There... I said it again.

 

The argument "you probably wont have that happen" in regards to rollovers at an auotx is a terrible one when it comes to safety. Safety devices are made explicitly to plan for the unexpected or else you wouldn't need them. Rollovers on track are a very real issue so why they only hold a "bit more water" in your mind is beyond me. Please just dont sue Schroth if you end up in a wheel chair I may consider the autox only harness idea as there is a very low chance of a roll in that situation and I could use the stability, but what I said above still is relevant.

I currently have 265/35-18 NT05 rubber on 18x9.5+15/+35 (F R effective due to spacers). I have no fender rubbing, though a lot of plastic wheel well rubbing, up front and only under very heavy track pressure do the rears hit the unrolled fenders. You think I could get away with a 285 on a 9.5" if I roll the fenders? I think its a good possibility. I also think I will pick up the tires used and a cheap set of rims (NT03s?).

I was looking at sways earlier but got turned off at the proposition of the front exchange... What bars do you guys like? The Whiteline seem like quality pieces but are relatively inexpensive. 24mm rear? 26?mm front? And I have heard endlinks are a must. Thoughts?

 

Re: rolling over --- why get out of bed at night? There's inherent risk in that too. Make an informed decision, and run with it. Life's too short. I'm MUCH more concerned with a crash into a wall that a HANS device would help with than I am with a rollover (as there have been more deaths in the former than the latter).

The only experience on an 8/9 with 285s has been on 18x10.5 RPF1's +15. Those required new fenders. 285/30/18 A6's are going to be easily 2" wider than those NT05s you have now (they run wide whereas the NT-05s run narrow). They are also shorter, so you'll have more clearance. On the X, with those tires/wheels you just need to roll and pull the rear fenders and a slight pull up front to clear (assuming you're lowered). You'll rub the crap out of the plastic too. Without the aggressive offset you might be hitting your suspension components. You might check that out.

If you do go with the A6's you're going to need more springrate and sway bars. They have MONSTER grip when new and will really show the weakness of your springs.

Definitely get the front sway. It's a pain to install (a lift helps), but it likely has made the biggest difference for me (I'm in an X though).


I bought a set of used A6's from a guy with a BMW (alex at bmwe30.net). He's got some for sale now for about $300 a set shipped. They were in pretty good condition. I corded a couple of them because I wasn't running enough air pressure (A6's love pressure), but the other two easily have 40 runs on them (from me, something like 50-60 from him).

Re: NT-03's I think you're going to need spacers to make those fit the calipers. I'd rather get something that didn't require spacers (since you're going to need all the room under your fenders than you can get).

 

I dont know why youd want to get out of bed at night, I usually do that in the morning I understand your point, but adding a harness inherently adds some risk even if it is small. At this point, I would rather sacrifice the marginal performance gain from being planted in the seat than add the, albeit small, risk of a harness. I do enough circuit track day stuff with speeds well over 120mph that I may look into a roll hoop or something like that and then the harnesses would be a no brainer. I think we have beat this issue to death

I will likely get the F/R sways and endlinks (great package deal from MAPerformance BTW) and bite the bullet on the install, I do have a lift . Again, any recommendation on size and brand? If I bought right now I would go all Whiteline and get the larger 24mm rear sway and the 26 or 27mm front.

What rates do you run? I believe my shocks are good to something like 12-14k according to an AMS test but I dont remember the specifics. I do daily drive this car and the 7/9k already rattle my brains. Though that may be attributed to the 8/10 and 6/10 (F/R) damper stiffness settings.

Sounds like the A6 is a solid used investment, 40 runs on a $300 set of race tires is substantial AutoXing. I do not want to heavily modify my fenders or replace them to fit another 2 inches of rubber so I would likely go with a 265 width. I do have EvoDave's front fender kit which afforded me 3/4"- 1" of extra clearance.

The NT03's in +38 would require a spacer to clear the caliper, exactly as the RPF1s do. I have a 23mm adapter up front and a small 3mm spacer in the rear (mainly for the hubcentric ring and to pull the tire a small bit from the trailing arm). What rims do you like if not the RPF1s (which I love mine) or the NT03's?