Rallycross Question - Can I used a Miata build for autocross and time trials for rallycross too?

Snowdoggie (Forum Supporter) said:

Somebody told me that the bolt pattern of at Jeep YJ and the NA Miata were the same. I could put my Jeep tires on the Miata. 

NC, not NA.  

If you are on hardpacked dirt on the line, you want 200TW tires.  They are the fastest on dirt too.  If you are in really really loose stuff all the time, then you want something else.  I see cars on all seasons, RE71s and rally tires on our events here.  The FTD is always from a car on RE71s and with a good driver :).  I'm not a good driver. 

Snowdoggie (Forum Supporter) said:

thatsnowinnebago said:

There's always this offering from Paco: https://pacomotorsports.com/product/rallycross-coilovers/

I am taking a good long look at their skidplate. That might even be good to have driving on the street. 

This is probably the real controversial take of the thread, but I've never run with a skidplate and never had any issues that a skidplate would realistically have prevented. Of course I'm talking stock ride height cars...if you're running slammed autocross ride height it's probably a good idea.

Lightly worn out stock suspension is fine...make sure there's still functional bump stops in there though.

Snowdoggie (Forum Supporter) said:

Somebody told me that the bolt pattern of at Jeep YJ and the NA Miata were the same. I could put my Jeep tires on the Miata. 

Somebody gave you bad information. A quick eyeball at the number of lug nuts would tell the tale. I don't think Jeep has ever used a four bolt wheel. Well, not on purpose. There have undoubtely been Jeeps rolling around with only four nuts on their wheels :)

Now, a YJ and an NC Miata, that looks to be compatible. The NC uses the very common domestic 5x4.5 pattern.

In reply to Keith Tanner :

Maybe it was my Mustang I could put XJ wheels on, not the Miata. 

So that means I could put NC Miata wheels on the Mustang. 

I have been waiting for a Miata with Torq Thrusts (or equivalent) wheels. SOMEONE!

IMHO a good rule of thumb for basic rx suspension setup are springs in the range of 150-200% of stock rate, with a static ride height at close to that of stock. Should keep decent geo, comp/droop travel, and likely work with a mild damper upgrade ( billy HD's are a good starting point). Your driving style and typical course conditions can guide you from there for rate and ride height adjustments. 

Edit: fresh bumpstops are also crucial. After a couple events, play with disconnecting the sway bars to see what you like/works, too.

Keith Tanner said:

I have been waiting for a Miata with Torq Thrusts (or equivalent) wheels. SOMEONE!

The 17" lookalikes from the Bullitt Mustang were pretty popular on FC RX-7s for a while.

Not a Miata, but call it a proof of concept 

bluej (Forum Supporter) said:

IMHO a good rule of thumb for basic rx suspension setup are springs in the range of 150-200% of stock rate, with a static ride height at close to that of stock. Should keep decent geo, comp/droop travel, and likely work with a mild damper upgrade ( billy HD's are a good starting point). Your driving style and typical course conditions can guide you from there for rate and ride height adjustments. 

Edit: fresh bumpstops are also crucial. After a couple events, play with disconnecting the sway bars to see what you like/works, too.

This advice seems really good.  I've been thinking about rally springs that lift the Impreza 0.5" only and Koni sport inserts for the jump to prepared 4.  
 

The only lifted Impreza that ran at North TX did end up on its side at one event.  Sadly I don't know of any videos or photos of it.