Does anyone Rallyx their ST?

[M-Sport fan]

I just ordered a bunch of those low pro nuts. Thanks for the link. Gonna do some measuring today thanks to all this info. Really appreciate this and everything else @Dialcaliper !!

The offset of the wheels and tire width (yes, along with whether or not the car is lowered at all) have the most to do with that rubbing on the front RallyArmor flap mounting studs/fasteners.

My car is still on the full factory suspension, albeit almost 7 years old with 43K miles on it.

My street daily driver setup 16x8, ET40 Dekagrams with 205/50-16 Neo Gens rubbed to the point that I had to remove the flaps and mounts completely until I can do the above Dialcaliper mod to them.

On the other hand, my just as tall, but much more narrow and 'inboard' winter/rally working setup 15x7 ET48 Method MR501VTs with 195/60-15 Arctic Altimaxes on them do not rub at all, under any circumstances at all.

 

[M-Sport fan]

I was torn between the Winrace Lars and the Winrace A16. Ended up going with the Lars because rallycar heheh 😏

I’m a bit illiterate with offset. Paul their President and CEO (who is rad btw) is gonna work his magic. I told him OEM offset is 47.5 but I think he said something about 37.5 if I recall correctly?

I did not even know they made a OZ Leggenda style 'vented disc' rally wheel until you posted this above.

SWEET!

The A16s are also nice, and the Acropolis would have been my choice for gravel/dirt yes IF they were even made in the 16" sizes you need.

 

[stash3630]

The offset of the wheels and tire width (yes, along with whether or not the car is lowered at all) have the most to do with that rubbing on the front RallyArmor flap mounting studs/fasteners.

My car is still on the full factory suspension, albeit almost 7 years old with 43K miles on it.

My street daily driver setup 16x8, ET40 Dekagrams with 205/50-16 Neo Gens rubbed to the point that I had to remove the flaps and mounts completely until I can do the above Dialcaliper mod to them.

On the other hand, my just as tall, but much more narrow and 'inboard' winter/rally working setup 15x7 ET48 Method MR501VTs with 195/60-15 Arctic Altimaxes on them do not rub at all, under any circumstances at all.

So my extremely limited knowledge on offset says that my new wheels at 37.5 are going to be MORE outboard, correct? In which case, make it more likely to rub with a taller tire, correct?

Here's some tire size comparisons I did. OEM 205/40/17 vs 195/50/16 vs 195/55/16. Maybe the 37.5 offset will change my/our thinking, but I feel like the 195/55 is going to rub based on how little room there is in there on the stock 17's. Anyway, please take a look at these pics friends and tell me your thoughts

Stock rims vs: 205/40/17 vs 195/50/16



195/50 vs 195/55


Stock rims vs: 205/40/17 vs 195/55/16


Look at this last image. 195/55 is a full extra inch of height from oem full wheel diameter, but by dropping rim size by an inch I do get a FULL inch of extra sidewall. But still, 23.5 to 24.4 total diameter seems like a big jump to me. Maybe your offset @Dialcaliper allowed you to pull this off?

(@Dialcaliper @M-Sport fan @asidrive @tri-pedaler )

 

[Dialcaliper]

So my extremely limited knowledge on offset says that my new wheels at 37.5 are going to be MORE outboard, correct? In which case, make it more likely to rub with a taller tire, correct?

Here's some tire size comparisons I did. OEM 205/40/17 vs 195/50/16 vs 195/55/16. Maybe the 37.5 offset will change my/our thinking, but I feel like the 195/55 is going to rub based on how little room there is in there on the stock 17's. Anyway, please take a look at these pics friends and tell me your thoughts

Stock rims vs: 205/40/17 vs 195/50/16
View attachment 57449


195/50 vs 195/55
View attachment 57450

Stock rims vs: 205/40/17 vs 195/55/16
View attachment 57451

Look at this last image. 195/55 is a full extra inch of height from oem full wheel diameter, but by dropping rim size by an inch I do get a FULL inch of extra sidewall. But still, 23.5 to 24.4 total diameter seems like a big jump to me. Maybe your offset @Dialcaliper allowed you to pull this off?

(@Dialcaliper @M-Sport fan @asidrive @tri-pedaler )

That same website has a much better "Tire Offset Calculator" that lets you put in both the tire size and the wheel diameter/offset and does an overlay

Link
https://tiresize.com/wheel-offset-calculator/

For example, part of why I picked the 16"x6.5" et38 wheels (instead of a et47.5 wheel I also found for my 195/55R16 snow tires is that the 38 offset puts the outside face of the narrower tire very near (~1/8" out) where the outside wall of the OEM tire sits (instead of having the same centerline with a narrower tire). They poke less than the 215/45R16's on et42 wheels and those of course fit fine even on most FiSTs lowered at least an inch.

I will say that I did a lot of research on this same topic, and while you can get away with 1" additional tire diameter without rub, that's really at the limit, and anything too much wider than 195 tire may run into issues at that sidewall height. I would also not try to run the 1" taller tire on a car that's lowered much below stock height or you will likely rub. But presumably that's not what you're after in a RallyX setup

Below are the numbers the snow setup I'm using along with the shortened mudflap nuts. As is, there's a minumum of 3/8" clearance to the nuts with the car still and so far I haven't had any rub issues on snow or dirt. I had them on the stock springs for a bit and they seemed okay - the new spring setup also means slightly less bump compression than stock so it also helps a bit there.

https://tiresize.com/wheel-offset-calculator/

 

[M-Sport fan]

Yes, at that offset (ET 37.5) the tire (tread and section) width will have more relevance in whether or not it rubs against those flap mounts as the height will.

Although Dialcaliper is absolutely correct in telling you that 1" taller than the factory setup's height (i.e.; 24.3" tall or so) is the max you should attempt, whether on factory suspension, or even a raised aftermarket suspension, due to the wheel travel, and severe compression bumps you could face in your RallyCross use.

Once I removed my Rallyarmor flaps, my street setup 16x8s even with their ET40 and wider than most others out there, 24.2" tall 205/50-16s never ever (even on tarmac big dip compression bumps, or severe braking), rubbed at all.

It might not rub once I do the 'Dialcaliper mod' to those flap mount hardware pieces, but I won't know until I get the chance to try that, with the re-install of said flaps on my ride.

 

[stash3630]

That same website has a much better "Tire Offset Calculator" that lets you put in both the tire size and the wheel diameter/offset and does an overlay

Link
https://tiresize.com/wheel-offset-calculator/

For example, part of why I picked the 16"x6.5" et38 wheels (instead of a et47.5 wheel I also found for my 195/55R16 snow tires is that the 38 offset puts the outside face of the narrower tire very near (~1/8" out) where the outside wall of the OEM tire sits (instead of having the same centerline with a narrower tire). They poke less than the 215/45R16's on et42 wheels and those of course fit fine even on most FiSTs lowered at least an inch.

I will say that I did a lot of research on this same topic, and while you can get away with 1" additional tire diameter without rub, that's really at the limit, and anything too much wider than 195 tire may run into issues at that sidewall height. I would also not try to run the 1" taller tire on a car that's lowered much below stock height or you will likely rub. But presumably that's not what you're after in a RallyX setup

Below are the numbers the snow setup I'm using along with the shortened mudflap nuts. As is, there's a minumum of 3/8" clearance to the nuts with the car still and so far I haven't had any rub issues on snow or dirt. I had them on the stock springs for a bit and they seemed okay - the new spring setup also means slightly less bump compression than stock so it also helps a bit there.

https://tiresize.com/wheel-offset-calculator/
View attachment 57452

Wow. The offset calculator on that site is amazing. What was already a pretty darn cool website is even radder knowing the offset calculator is in there. Thanks so much @Dialcaliper for the heads up on that! Serious game changer and peace of mind using that feature.

How much off-roady / rally stuff have you and @M-Sport fan done with this setup? My concern is that even using your high speed tarmac compression on a dip as an example where the car didn't rub, I feel I may still have deeper suspensions compression on a RallyX course. I will say though that I had a wheel rub issue in my 84 911 Carrera (low-key flex) and that issue only liked to appear on super high speed deep compressions like what you described; so I agree that in itself is a solid anecdotal metric.

I stuck a tape measure between the top of the OEM wheel setup and the top of the front fender well and it seems like there's roughly about 3" inches. So losing a half an inch there doesn't seem like it'll be too bad? And the outer sidewall being .15" inches further out seems nominal enough not to worry either. The plastic in the front fender wells seems pretty easy to work with too, were I to have to make some modifications. (Fender well clearance in the rear was closer to 5" inches btw so no real worry there I suppose)

So all this and what has been said above, I'm gonna try the 195/55 (the low pro nuts for the flaps arrived yesterday). I was talking to a Porsche friend who is a helluva wrench about all this yesterday and he said, "How much are these tires?"

Me: "Like $120 per"

Him: "Um ok, so just give the taller tires a shot and if they don't work, take em off and sell em...."

Me: ".........That's a real good point. I probably coulda saved the forum friends a lot of back and forth by just using this logic"

So my friends, thanks so much for all your help! I'm gonna do the 195/55/16 and we will see how it goes!
Thanks so much again to everyone here that has offered their help and extreme patience. I went from never being able to remember that the second number in a tire size was the aspect ratio, to fully nerding out on offsets, ride heights, full diameters and sidewall size numbers etc etc. I love learning stuff like this so thanks all again!

 

[asidrive]

Fiesta ST Takes the win at this past SCCA Rallycross Nationals. Brad is a great driver I raced with in Utah but was in a Mod Front car that kept having issues. One local event he jumped in my Fiesta after a breakdown and ended up buying his own the next season. He took the win by 27 seconds but it would have been a battle with the mini driven by Josh if it didn't have mechanical issues. Very excited to see a fiesta at the top and maybe we get more Fiestas out after seeing this result.

 

[M-Sport fan]

Do you know what (allowed by the rules) mods are done to his ride?

 

[asidrive]

I think it's stock aside from maybe Bilstein shocks. Oem sways, some wheel and winter tires.

I have a couple of 2nd place finishes at nats with a larger front sway bar but I think it might be too much for rallycross and hurting grip although I like having less body roll.

 

[stash3630]

Always good to see a Sentra SE R get beat too! Those cars are head scratchingly good for RallyX.

I ran my ST in the stock class for awhile, but ultimately couldn’t get the idea of a real mechanical diff out of my head. While the diff and other mods punted me out of the stock class, it did allow me to go down to 15” wheels and gravel tires 😊

 

[M-Sport fan]

Always good to see a Sentra SE R get beat too! Those cars are head scratchingly good for RallyX.

One rarely sees them used in any class of real, full speed, full safety equipment required ARA stage rallying, and even when they are the car choice, they are almost never winning their class.

Didn't they come right from the factory with a clutch pack style limited slip diff, or was it an option?
Maybe that's why they are so good in stock class SCCA Rallycross?

 

[asidrive]

Always good to see a Sentra SE R get beat too! Those cars are head scratchingly good for RallyX.

I ran my ST in the stock class for awhile, but ultimately couldn’t get the idea of a real mechanical diff out of my head. While the diff and other mods punted me out of the stock class, it did allow me to go down to 15” wheels and gravel tires 😊

I've been very close to pulling the trigger on a diff because I think the fiesta would be an amazing prepare front car. Only thing holding me back is racing in HS for autocross as well. Once you go beyond stock/street class, it's hard to have a decent car at both.

 

[tri-pedaler]

Fiesta ST Takes the win at this past SCCA Rallycross Nationals. Brad is a great driver I raced with in Utah but was in a Mod Front car that kept having issues. One local event he jumped in my Fiesta after a breakdown and ended up buying his own the next season. He took the win by 27 seconds but it would have been a battle with the mini driven by Josh if it didn't have mechanical issues. Very excited to see a fiesta at the top and maybe we get more Fiestas out after seeing this result.

Saw this on FB - great to see this platform winning

 

[tri-pedaler]

Just started looking for rallyX events near me - nothing with my region anymore unfortunately (Indy). Looks really fun though

 

[stash3630]

One rarely sees them used in any class of real, full speed, full safety equipment required ARA stage rallying, and even when they are the car choice, they are almost never winning their class.

Didn't they come right from the factory with a clutch pack style limited slip diff, or was it an option?
Maybe that's why they are so good in stock class SCCA Rallycross?

I (unfortunately) haven’t been around much stage rally, but I’m not surprised to hear the spec v is notably absent. They weren’t even on my radar until I saw them flying around our local courses.

What I think the SE R Spec V does have, which is clearly good for RallyX, is a stock diff and a 200hp 2.5L 4 banger that makes nearly 200 lb of torque at 5000rpm. So for tight slow second gear RallyX laps it seems to do really well. I think they’re really boring looking, but alas I came in second to one yesterday so I can’t talk too much 😂

 

[stash3630]

Just started looking for rallyX events near me - nothing with my region anymore unfortunately (Indy). Looks really fun though

I know Indy is a big state, but the St. Louis RallyX scene looks pretty active?

 

[faust]

I'm thinking about trying out a rallycross event this summer. How hard do you guys find rallycross to be on the car, are you seeing much additional wear / breakage over and above driving on the track? Is The Skid Plate Guy still the easy button (just emailed him to see if that's still an option)?

 

[M-Sport fan]

I'm thinking about trying out a rallycross event this summer. How hard do you guys find rallycross to be on the car, are you seeing much additional wear / breakage over and above driving on the track? Is The Skid Plate Guy still the easy button (just emailed him to see if that's still an option)?

Yes, as most other options include either much welding, and or fabrication, or if 'bolt-on' do not offer as much protection/strength as the SPG option (IF still available).

If the ARA does not add a National level stage rally to the east coast/northeast soon (there used to be THREE of them, now NONE! ), I may have my Skid Plate Guy bash protector up for sale.

 

[asidrive]

I'm thinking about trying out a rallycross event this summer. How hard do you guys find rallycross to be on the car, are you seeing much additional wear / breakage over and above driving on the track? Is The Skid Plate Guy still the easy button (just emailed him to see if that's still an option)?

I have been rallycrossing and autocrossing my car for the last 3-4 years. While I personally don't think rallycross is much harder on the car than other motorsports, it's definitely not easy on it. In that time other than general maintenance, I've had to replace a couple of sensors, transmission mount, shocks, and one axle. The axle was due to my passenger side motor mount bolt snapping and shifting my engine but this can happen even on a street-driven car apparently and I missed the memo to replace that bolt before it broke.

With that said, I did do a lot of work this off season just refreshing all my motor mounts, sway bar bushings etc. Even after a few washes, street miles and autocross events, there is still dirt everywhere so I firmly believe I would never get all the dirt off the underbody but I also have never tired knowing there could be a muddy event at any moment bring it back to where it was anyway. Now my goal after a rallycross event is to get the car to the point I don't piss off the autocrossers by dropping too much dirt on their course. I have been told that my car was burning oil but it truly was just dirt. This was with minimal cleaning effort from a Saturday Rallycross followed by a Sunday autocross.

I use the ADF customs skid plate. I think its fine for street use and rallycross, its nowhere near as robust as the skid plate guy version.

 

[faust]

Cool, good to hear some practical experience. I'll take a look at the ADF skidplate option.

I missed the memo to replace that bolt before it broke

Do the passenger side motor mount bolts need regular replacement, or was there some kind of warning sign that yours was on its way?