RallyX Course / Ride Height Question

https://grassrootsmotorsports.com/forum/grm/dirt-dust-fun-an-introduct/191238/page1/#post3748435

The pics in this post reminded me of question(s) I have regarding rallyX courses / venues and tire choices. They show wet, rutted and uneven surface areas. The same as I have seen on other posts.

However, where my local group runs it is completely the opposite. Here (northern AZ) the venue is a parking lot for other events – it is small “pea” gravel / dirt and pretty much flat. Plus it gets smoothed out at the mid-day break. It really looks like autocross on dirt.

This is the only rallyX venue I have seen in person so my thought is to lower the car, via tire size, a bit.

That said, I’ve seen responses here to rallyX questions that mention raising ride height. Is there any other reason to raise the ride height other than the terrain?

Only that.

Technically all courses must be safely navigable by 100% stock vehicles with no additional protective equipment.  Ruts and stuff happen, of course, but as a general rule lower is better.  You're trying to navigate a course with essentially no straights, raising a car does not make for good cornering.  DRSCCA runs on venues like that, hard and smooth and fairly low degradation, and the fast way around turns out to be a more supple autocross setup, including tires.

Even so, I would not ever deliberately make a car higher, for any course.  If it's rough enough that you are worried about underbody damage, it's rough enough that rolling is a bigger concern IMO.

I have seen people show up to events in Miatas on those ridiculous Paco lift setups and it is painful to see how slow they are, and their width takes away the Miata's natural advantage of being able to take certain features straight.

Stock, stock or stock; your choice.

Pete. (l33t FS) said:

I have seen people show up to events in Miatas on those ridiculous Paco lift setups and it is painful to see how slow they are, and their width takes away the Miata's natural advantage of being able to take certain features straight.

Yeah that one. I think there's a lot of mod class cars with real rally suspension that are slightly higher than stock ride height that work well but I don't really count that. I can only think one one case of a "lifted" car working well, and even that I think is as much or more tall tires as actual suspension lift. Every other one has just been a mess of excessive body roll and no lateral grip. You want exactly as much ground clearance as you need to not bottom out frequently to the extent of causing damage (note that's not the same as not bottoming out at all).

The only reason my MF Neon is slightly higher than stock is to keep it from snagging on the trailer because the ramps I have are really just too short.

There are some sites that have some pretty rough surfaces and I will consciously go a little slower over the worst of those spots to try to keep from damaging the car.  Without some really serious modifications, though, I don't think that I'd be able to raise the car enough that it would matter, as far as changing the risk that something on course could hole my pan.  And, like Pete said, raising that much would kill your stability in the corners.

Some cars, though, do have some awfully low-hanging accouterment in the front-end, be it an air dam or an oil cooler or the radiator.  I think those tend to get damaged or ripped off when the car porpoises a bit.

My air dam is long gone - I guess I took it off at some point?  I don't think it fell off and I don't think I removed it with the intent to leave it off, but at some point between when it left the factory and now it was removed and never put back on.  The intercooler is up there, but it's never collected anything other than bugs and dust.  I also don't run a skid plate because I've never gotten around to building one.

If you're going to run on a surface that is that flat, I wouldn't go any higher than stock ride height.  If you wanted to bring it down a little bit, that probably wouldn't hurt - just make sure your exhaust is hung properly and watch your front fascia.

AnthonyGS (Forum Supporter) said:

Stock, stock or stock; your choice.

At this point I intend to keep the car within the SCCA Stock Rallycross rules. Among other things allowed are:

• Alternate tire sizes are allowed but tires may not interfere with any parts of the car (fenders, fender liners, suspension, etc.).
• Wheel diameter may be increased or decreased one inch (1”) from the OEM wheel

In reply to Pete, dps214, wae

Ok, I my case, venue with a flat surface, I have no reason to treat this as anything other than an autocross on dirt. If I can find the right tire / wheel combination I will start there.

Thank you