Just a quick update. The autocross at homestead last Sunday didn't go very well. Basically, the car didn't turn well at all. Turn in was ok but the longer the car was loaded, the less it would turn.

We ended up finding that the steering rack was moving as much as 1/4" in each direction (with the car sitting in the parking lot!) Imagine how much the rack was twisting under load in a corner? Apparently, as you would turn the wheel a corner, the turning tire would pull the rack and the tire would toe out causing an extreme push condition.

Anyhow, the fix is to strengthen the front subframe both in the front and the rear. A trip to Lowes for some miscellaneous steel and a borrowed welder seems to have done the trick. We welded a section of 1" box tubing to the existing crossmember plate at the rear under the oil pan. In the front, we fabricated spacers from 1/4", 3/8", and 1/8" steel to space the steering rack up almost 3" (this will greatly help with bumpsteer angle and front steering geometry). Then, we welded the spacers together once the rack was level with the chassis. Finally, we welded a 2" wide 3/8" thick piece of steel to the front of the spacers to box in the subframe.

3 very late nights later and we're done with the welding. The new front spacer bar is being painted and will be installed today. Then we'll do a quick DIY alignment to be ready for Sebring tomorrow.

So, since the last update:

-Relocated kill switch to A/C vent hole in preparation for small rear view mirrors
-Fabricated brackets to hold the hood prop where the wipers used to live
-Reinforced front subframe with box steel in the rear
-Raised steering rack 3" to improved steering geometry
-Reinforced front subframe with welded spacer bracket in the front
-Relocated brake ducts to openings in front lip
-Rewired gauges correctly so they retain their warning settings and shut down properly
-Retightened bolts around the car
-Ducted the radiator/oil cooler to the front bumper to aid with air flow
-Began designing a brake master cylinder brace (this won't be done in time for Sebring)
-Adjusted harnesses for shorter people (heh)

And some miscellaneous this like an extra set of Hoosier R3S04's (5 of them), and a set of Bridgestone RE950 rain tires on the stock 14's.

We'll see if these changes made a difference tomorrow!

 

have you corner wieghted the car yet?

 

Yes sir, it's within 15lbs on the diagonal.

 

Some pictures of the front subframe and steering rack modifications:



Bending up the passenger side mount:



Steel cutting:





Meanwhile Jose relocated the kill switch to the A/C vent to prepare for future rear view mirrors:





Here we were adding shims to level the rack and raise it:







The new addition to the center subframe connection:



The result of raising the rack, now bump steer should be minimized because the tie rod angle is almost parallel to the lower a arm angle:





Once we had the rack raised and leveled, the spacers were all tack welded to each other:













Then, we took the spacer "blocks" off and finish welded them:





Learning to weld =)











Cleaning it up:







We then welded a 3/8" thick bar across the front to close the box:

 

Some paint on the new box brace:



Painting the new front spacer/brace:





Installed:











New (to me) used Hoosier R3S04s I snagged for $250:





Hood prop bracket fabrication:







Installed:



Preliminary design for Brake Master Cylinder brace (I think we're going back to the drawing board on this one):







Once we had everything together, I borrowed Phil's alignment tools and aligned the car (thanks Phil!)











...And with that, we were off to Sebring to try it all out!

 

So we get to Sebring and the car makes it to turn 15 out of 17 and breaks. Smoke filled the cabin to the point where I couldn't see the gauges or even my dad in the passenger seat.

Turns out, the rear of the transmission housing cracked, severely. So we pick up the pieces and head home to figure it all out before homestead next weekend. Last night we took down the exhaust, driveshaft, power plant frame, and trans brace. Then we removed the back of the transmission and found this:









We're not really sure exactly how it happened but I think we're going to try running with the big horizontal custom transmission brace disconnected. The theory is that it will allow the trans to flex and not crack. We're picking up a used transmission today and installing the rear housing on the car for Homestead this weekend.

 

Hey Yall watch this.......

 

Ouch.

 

I got my pussy ass laid flat out on the lawn by the transmission

 

Alex, are you mounting the tranny to the diff. like the stock Miata configuration? I am not sure if the S2000 uses something similar or not, but you might be flexing the tranny, with the rear end. Also, if the front sub frame is allowing the engine to move up and down, it could cause the tranny to flex because it is being supported by this middle brace you are talking about.

What kind of numbers did you get from the alignment?