What did you weld inside the belhousing?

Have you looked into 949racing's twin clutch setup? A bit more weight but may hold up better. And their pulley or an ATI super damper would help with harmonics as well.

Fae, I am running a Quaife Sierra dog box, if you look you can see two plates that make up the adapter, one plate is mounted to the transmission case, and one is welded to a shortened bell housing, that plate serves as a mounting surface for the throwout bearing and is also bolted to the plate mounted on the transmission case.
https://www.miataturbo.net/attachmen...ine=1349495748

The plan at this time is to repair the crack in the bell housing. I will separate the two mounting plates and bolt the bell housing to a bare block to ensure that all bolt holes and alignment dowels are in proper alignment while welding.

Building a new engine for next season, my current engine is the one that came with the car. It is a small nose crank engine, I have not been able to find an aftermarket harmonic dampener for it. The new engine is a big nose engine, I will be using a aftermarket damper that has a trigger wheel for my electromotive incorporated into it. I hate to move away from my current clutch setup as I have two complete setups, one new in the box. However, a heavier flywheel will help with harmonics and will prevent the issues I had at the end of the race. It will also make it a bit easier to get the car moving, I have a tall 1st gear, runs out to approx 58mph at 8k. With the current flexplate/flywheel, 4 1/2 inch clutch, and cams that are worthless below 4500 rpm, getting the car to move off grid or in the paddock is a real adventure. It was really tough to get it going at RA because the grid is located on a hill.

Holy hell!

How on earth did you manage to even finish the race with that thing flopping around inside the bellhousing? It must have sounded like a washing machine full of hammers.

Honestly, After it broke I think it sat against the bottom of the bell and just moved back and forth ever so slightly, the big chunk was laying at the bottom. I think I got real lucky with how it broke and came to rest. There was some vibration the last few laps in 5th gear, but hey its the runoffs, and I was running in 6th so I kept my foot in it.

Here is a video of the first couple of laps. Remember I only had 7 laps at speed on the track before the start of the race. I left the pace lap so people that have not been to the track can see a lap at a slow pace.