Subaru Impreza RS RallyX advice

Maybe some have noticed, maybe some have not, but I bought a 2002 Subaru Impreza RS for the intended purpose of putzing around on the Rallycross course recently added by North TX Rallycross.  It's an odd name for it, since the course is physically located in OK, but that's they way things go.

Anyway, I have some autoX experience, some drag racing experience and some lapping experience.  I'm not hotshoe, but I'm not John Q Public either (or maybe I am). 

I have zero knowledge of Subies (maybe it's not that bad, I did get it home), and zero knowledge of RallyX.  I noticed the stock rules for it and autocross do not correlate well on shocks, etc.  I'm not sure that matters.

Anyway, I found a stock, clean, 150k mile Subaru RS bugeye and bought it.  I found a lot of modded WRXes, but most had mods that would have to be reversed at great expensee for RallyX.  I do know another RS rolled onto it's side in NTX RallyX and it was lifted.  I do not want to lift or lower the car.  I really want good suspension at factory ride height.  At 150k miles the stock struts have no life left to give (or very little).

Honestly I think I need:  1)  A skid plate and maybe a skid plate for the rear diff.  2)  Mudflaps to keep from making the paint look horrible, and 3) new struts and maybe top mounts etc.  4)  Snow tires for my stock 16s or maybe even a set of Rally oriented 15s. 

What say you that knows Subies and know RallyX? 

The want list would be more power after learning the car and dedicated rally tires and wheels along with a nice rally suspension.....  I'd also like more brap noises, but don't want a huge import style muffler that will get pancaked on a rallyX course either. 

The roof rack is already removed and for sale locally. 

The engine is burning oil.  As I understand it in Subie's that is oil control rings shot.  Do I want to pull it and do the rings, or just get a new shortblock eventually, or should I just go all in on a turbo swap with a FMIC to keep my low RS hood?   The plan is just to watch it and add oil for the first season (2021). 

Wow, awesome car.  I have some comments, but they are not going to be as helpful.  My son just ditched mustangs and miatas for a 2002 wrx sedan.  Being in maine, we are just having trouble with some non typical, but still rust issues. I am following my son as he decides what to do with the car.  He is now planning to get back into auto cross, but he def isn't going to rally cross the car.    He wants to mod the muffler, but  is running out of money, so it will be some cheapie that he gets from amazon.  He is hunting down a missfire, and that is taking his budget down.

As far as more power: This thing has plenty,  it is just getting the car to run well.  I don't know about adding more power to these things, I am really impressed with these cars.  For me, I'd put some coil overs and sticky tires on it and see how it goes.  My son is  not wanting to over mod the car, but we will see.  

I am trying to have my son pick up an engine, build it stoutly and then play with the boost.  I would rather have a car that I can beat on and not worry about ruining the engine.  These cars are really great.  I now understand why people love these cars.

No Subaru experience, but a decent amount of rallycross experience. What size tires do the 16s take? You basically want as much sidewall as possible, if 15s fit and are cheap it's probably worth it. There's other variables but in general my experience has been that the taller and softer the sidewall is, the harder it is to debead, which is the biggest issue with awd cars. As for the tires themselves, that's going to depend on surface and conditions. There have been some mixed reviews here lately, but my last rallycross car had a set of cheap bilsteins on it, and they were phenomenal for rallycross, and street driving for that matter. I've never run a skid plate beyond an oil filter guard, but then again I've also had to re-weld a radiator support. I think Subarus do tend to have more stuff hanging down low, especially with the engine so far forward, so the plate is probably worth it. Not sure I would bother with the diff plate though.

you will always be slower than the turbo cars. all the subaru people at my local region are on their 4th-5th engines both NA and turbo. so go ahead and stock up on engines.

I would bet http://www.dirally.com/forums/ has whatever you need to know covered, but I'll take a guess anyway.

Some sort of stock replacement strut, Bilstein HDs are probably best if they make them for that model.  Make sure they've got fresh bumpstops, whatever you install.  Some sort of knobbly snow tire should work on the stock wheels, I usually like original Winterforces although they're getting hard to find or the Altimax Arctic.  Depending on the course layout, you might not need skidplates, although they're certainly nice to have.  If you want 15s, this style of stock wheel from earlier Imprezas has pretty good caliper clearance and should fit:

Stock are 16 x 6.5 with 205/55/16s.  Yes I think 15s fit and there are less expensive rally style 15s available.

Sadly there are no Bilsteins for these cars. It's KYB Excel, KYB AGX, Sachs, FCS, Gabriel, or Koni yellow inserts.  There are Tein adjustables too.  

And yes the NA is slower, but an NA Subie has won nats at rallyX, so I'm not sure it matters much in this case.  

Honestly 205/55 is probably plenty of sidewall if you don't feel like buying wheels. 15" tires are cheaper though. Again, not a Subaru expert, but I think the performance difference between turbo and na cars is less the power difference and more that the turbo cars get the better diffs. Based on your first post I think you know this, but konis aren't legal for stock class.

Nice looking Subaru. 

I have basically no experience with rallycross, other that I just ran with the North Texas rallycross group two weekends ago, on their last event of the season. Yes, in Oklahoma...

Maybe I'll see you next event. 

Took my stock 99 jeep cherokee, fits barely under their 65" height maximum. They said I could run since i didn't look to be eighteen wanting to flip it. Haven't been eighteen in close to 30 years, but I did put it in two wheels when I hit a rut in a turn.

The fastest honda crx also got on two wheels as did a fully prep desert racing vw bug.

Great group,  all friendly, was able to make about a dozen runs and could have done plenty more but needed to let the body relax after a few runs.

There were a couple Subaru running, including a white one like yours. It debeaded twice as they had 25lbs/in in the tires, then the ran other tires. 

The recommendation was to put a much pressure as the tires are rated for.

Some were running all terrains,  snow or rally tires.

A skid plate is probably not needed unless you run off course, which could happen.

Best of luck, I'll try and post some pictures. 

I only ran couple rally x when I had my WRX. It's wasn't scca sanctioned so rules were lil blurry. I ran stock class with stage one tune, sti struts painted black with some dirt thrown on to look like oem(I know cheater). 
As far as tires; I ran faster on Bridgestone potenzas then snow tires. After couple runs the track was packed and glazed over the amount of grip was insane. Was harder to slide the car but being able put power down was big advantage.

NA will be fine for rallyX, just focus on carrying as much speed as possible through every corner and not on how big of a slide you can do. It's all about momentum and keeping it, you will look slow, your times will be fast. That was always me in my heavy DD Legacy Wagon pushing the gutted Impreza's like yours. 

On our course up here stock ride height is fine, I'd go with a new set of struts all around to start like you said and depending on your rules maybe try to put a larger swaybar in the back (maybe OEM WRX works?) to help the car rotate. These cars are a lot like fwd cars in that trail braking will bring the car around nicely on the way into the corner and then picking up the gas transitions back to understeer on the way out, very easy and predictable. 

Loud exhausts are fun when you are motorsporting but keeping it quiet lets you have more fun outside of events without drawing extra attention to your shenanigans. I've got a nice gravel road route here that I hit on a normal basis sliding the car around all the corners working on technique, if I had a loud exhaust I would attract all sorts of bad attention from the people that live along it.

Maybe do your first event on whatever tires it is on (provided they aren't completely worn out) and see what others are running and go from there. 15" wheels and the proper rally tires for your course will be ideal but if things are dry you might be able to be competitive on something a lot more affordable. We run on clay here, in the dry I was always at or near the top on whatever Chinese snow tires I happened to have, when it was wet though we all got destroyed by whatever car had the proper rally mud tires. Maybe at the end of the day you will have a set of tires on the current 16's for driving there and back and in dry conditions and a set of 15's setup for when it is crappier or the course is looser/wet.

Thanks for the input.  Yes I was considering an adjustable rear sway bar too.  So maybe just mudflaps, shocks, a rear sway bar and go see how things work out.  

Anyone have a strong preference for KYB Excel GR2s or Sachs struts?  I've never been super impressed by KYB myself.  I wish Koni made an SRT for these cars or Bilstein had something.

No idea on the struts. Sachs oe stuff is pretty decent, but I have no idea what their aftermarket parts are like. Fwiw since someone mentioned it, running max tire pressure is great if you want to never ever ever ever worry about debeads and don't care about being 5+ seconds per run off pace. It's a balancing act, low pressures make a huge difference in grip especially on loose surfaces, but are more prone to debeading.

Adjustable rear sway, left foot brake, stiffer sidewall on the tires (if you need soft sidewalls to ease the compression then your suspension is too stiff), stock up on wheel bearings and wheel studs or get some arp wheel studs. The 2.5RS final drive is rallyx friendly, you can dance with turbo cars. 

Part of de-beads is driving style as well. The only time I ever pulled a tire off the rim I was coming too hot into a haripin and the car was understeering, in the moment I added more lock which is not the right thing to do here. With the front tires plowing I of course hit a rut or something and pulled the tire off the rim. It was all poor technique that caused the problem. That's not to say you won't run into problems while doing everything right and just getting unlucky. Making sure your tires are aired up (that means checking in between runs as well) and keeping them pointed mostly in the direction you are actually going will go a long way to keeping them on the rims.

Speaking of rims, alloys seem to hold up better than cheap steelies. I did get away with running steel rims on my first car but I've seen others lose them during runs. Typically the centers fail in some way like them pulling over the lugs. Once again, making sure things are tight (that means checking in between runs as well) and you are using the proper hardware will keep things working properly.

These are pictures of some of the ones that participated in the last rallyX. Not my pictures. 

You should try to make it to the rally cross in Maxwell, TX next Saturday. It's about 3.5hrs from DFW, between Austin And San Antonio. 

It's put on by Lonestar Rallycross.

Rally cross Nov. 21st

NoBrakesRacing said:

You should try to make it to the rally cross in Maxwell, TX next Saturday. It's about 3.5hrs from DFW, between Austin And San Antonio. 

It's put on by Lonestar Rallycross.

Rally cross Nov. 21st

 

I already made plans for that weekend for family birthdays.  I didn't know about their events!  Thanks for the info amd keep me posted.  I have a friend that shoots video at the NTX ones.  I can link if there is any interest.

MrChaos said:

you will always be slower than the turbo cars

Not necessarily.  The gearing is better and there's no lag.

On fairly high speed courses, a local and I have embarassed WRXen and STIs with a 2.5i wagon with blown shocks.

Well talked to the wife unit.  I may be headed to central TX with the car as is for the 21st.

I can stay in San Antonio at my parents Friday evening.

I ordered mud flaps, KYB struts, and new rubber top hats.  None of it will be here in time for the 21st I think.  If they struts are, I can get them done at least the fronts.

If this is as much fun as I think it will be, I could see building the car to prepared rules next year.

Now I just need to figure out how to change the title on my 3 Porsche build thread to:  The world is flat, 2 Porsches ( 911 and Boxster), and Subie RS.  

AnthonyGS (Forum Supporter) said:

I have zero knowledge of Subies (maybe it's not that bad, I did get it home), and zero knowledge of RallyX.  I noticed the stock rules for it and autocross do not correlate well on shocks, etc.  I'm not sure that matters.

Anyway, I found a stock, clean, 150k mile Subaru RS bugeye and bought it.  I found a lot of modded WRXes, but most had mods that would have to be reversed at great expensee for RallyX.  I do know another RS rolled onto it's side in NTX RallyX and it was lifted.  I do not want to lift or lower the car.  I really want good suspension at factory ride height.  At 150k miles the stock struts have no life left to give (or very little).

Honestly I think I need:  1)  A skid plate and maybe a skid plate for the rear diff.  2)  Mudflaps to keep from making the paint look horrible, and 3) new struts and maybe top mounts etc.  4)  Snow tires for my stock 16s or maybe even a set of Rally oriented 15s. 

What say you that knows Subies and know RallyX? 

The want list would be more power after learning the car and dedicated rally tires and wheels along with a nice rally suspension.....  I'd also like more brap noises, but don't want a huge import style muffler that will get pancaked on a rallyX course either. 

The roof rack is already removed and for sale locally. 

The engine is burning oil.  As I understand it in Subie's that is oil control rings shot.  Do I want to pull it and do the rings, or just get a new shortblock eventually, or should I just go all in on a turbo swap with a FMIC to keep my low RS hood?   The plan is just to watch it and add oil for the first season (2021). 

hey friend - you have basically the same impreza as the 2005 that i had.  like you, i had come from a (probably more casual then you) autox background but was spurred on by some friends to try rallyx.  you'll find that the RS is a great rig for that kind of racing - don't let anyone tell you that you can't trade punches with the turbo cars.  i did OK, won my class (2.5L or less, street tire) the first season out and was typically behind guys with more experience, not more power. 

i always raced it in "daily driver" form - regular all seasons, no specific rally prep outside of what was already on the car to make it fun to drive.  

some things i learned:

• you are correct, you DON'T want to lift it.  aside from screwing up the suspension geometry, it'll offer no real functional benefit other than making the car dangerous.  you want to keep your ride height stock, and if you intend to stay in stock class, get something like a KYB AGX to give you more control.   i ran in Prep AWD and used 2004 STi struts revalved by FEAL, and STi springs of the same year.  that combo was ideal, but is hard to find nowadays.  the stiffer struts gave the car control and flickability, and the springs were compliant enough, added rear bias, but kept the car off the bumpstops.
• grab a 20mm OEM rear sway from a WRX sedan (not wagon) along with the appropriate sway bar bushings.  the added oversteer is noticeable.  i think this is allowed in stock class?
• i also ran whiteline COM-C tophats which added about a degree of camber and caster.  i liked how it made the car drive on the street and it was fine for rally stuff.  not 100% necessary but if rules allow and you're replacing anyway, they do add some more control.  unlike on pavement, you don't want too much negative camber though, the tire shoulder has to be able to dig in.  i was sitting at about -1.5 degrees all around and that was plenty.
• you MUST yank the ABS fuse when you race.  it offers so much more braking control its amazing.  i could not get the car to slow down on gravel my first time out and a friendly racer gave me that tip.  next time around it literally cut my braking distance in half.  the archaic ABS logic in these cars cannot deal with the low traction you see on a rally course.
• i never got good at left foot braking but i'm sure it would help.  you need to pitch these cars deep on corner entry to get them to rotate, weight transfer is key.  once you start getting the car to rotate and slide on corner entry, throttle to keep it sideways and adjust steering accordingly.  i was never quick trying to be delicate with it.
• you want to run street pressure + about another 4 PSI so you don't de-bead.  the more aggressive your slide angle and the weaker/shorter your sidewall the more your chances of de-beading goes up.  if the car's plowing, don't add more steering!  stay way from ruts/berms if you can help it...you might not de-bead but you can get gravel/dirt stuck in the bead and it'll air the tire down over time.
• i ran RallyArmor basic flaps and they earned their keep for sure.  even with them i still shotgunned the valence under the doors and all the spokes on the rear wheels.  the shot below is a great example of the coverage you can expect.  they'll protect your immediate fender area but you'll still throw debris up the side of the car, and also pepper the chassis and rear arms.  personally i think you're better off making your own flaps out of flexible cutting boards and hardware for the price RA charges now.  no matter what you do, make peace with the fact that subaru paint is garbage and there's just no way to do rallyx and still keep it nice.  i tried.

• run 5W-40, not a 30 weight.  that will help your oil burning and its better for severe use according to subaru's manual anyway.  
• you're SOL on power for any reasonable cost.  i ran an ECU tune (2005+ can take advantage of that), header, catback, and a WRX intake duct.  felt pretty much as slow as stock.  if you're feeling ballsy, forget turbos, the EZ30R is the real answer to rallyx speed and you'll get to sound like a porsche.
• lastly, and this is the big one - get all the ride alongs you can, and rope all the experienced racers you can into riding shotgun and coaching you.  i didn't get the driving style at all when i started, i was behind the car's actions, scared of being aggressive, and way too weirded out by the sounds and sensations.  a kind gentlemen jumped in on my second run without any hesitation and by the third run i was starting to hang the tail out.  you'll find some of the best people in motorsport at rallyx events.  its a big family.  here's a shot of me getting schooled.

i never ran a skidplate of any kind.  never de-beaded a tire or had any reliability issues related to rallyx.  i would just show up, add some air, and drive.  i did replace a few bushings along the way, but those were to improve the car as a daily and not necessarily to fix broken things.  

i would have LOVED to get some real tires on it, it would have been a beast.  you have the good luck of now having the most popular make of car in rally.  find some cheap 15" subaru wheels of whatever flavor you can source and try to get used rally tires from a team (15's are the popular size, in 195 or 205 width).  you can of course also pony up for new rally tires from a couple of the small US distributors (Maxsport, black rocket, etc) if that doesn't work, throw some snows on your 16's, preferrably a studable pattern since they have some more meat around the lugs.  avoid ice tires or heavily siped treads, they'll shred to pieces.

any questions, just ask.  here's my old build thread if you want more in depth reading on my car specifcally.

you're lucky to be driving in an awesome region, have fun and get as much seat time as you can!

In reply to ScottyB :

Thank you so much for the detailed info and awesome photos!

In reply to AnthonyGS (Forum Supporter) :

you got it!  i'm excited to share since most people bypass the RS and go right for the WRX even though there's a lot to love about the barndoor simplicity of the N/A cars for rally fun.  

keep us updated!  first time you link a couple turns together in giant, 4 wheel drifts with a huge rooster tail out the back and the engine on the limiter, i'm 99% sure you'll be hooked.

I'd be looking at softer rear bars honestly.  2.5RS doesn't have a rear diff and its easy to spin the inside rear wheel.  Easy to test & swap though.  Other than that, just make sure its in good working condition and run it.  Address other issues as they come up.

If you get serious, you can always switch to a WRX.  Literally the only downside is premium fuel.  It makes bucketloads more power, has a rear diff, gets the same/better mileage, doesnt eat headgaskets, etc.  FWIW, I autoxed a 2.5RS for a while and then a WRX.  There is a difference in gearing, but it doesn't come close to touching the difference in power between the two engines.

My 04 always ran better on mid-grade (89 octane up here) and gave me better fuel economy with it. If you can feel a slight hesitation it's worth a try to see if it helps. I've never had a problem with rear wheel spin in my open diff Subaru's, it was usually my inside front out of tight corners but the center diff was on its way out at that point and I haven't driven it like that since replacing it.

Cleaned off all the ugly spots from the roof and bike racks.  Struts and mudflaps should arrive Thursday and the front strut rubbers....  wonder if I could get them installed by Friday afternoon and head down to Austin.