A Quick Update

 First update is the rear gearing. One of the primary performance issues I've had with the car is the gearing. Specifically, the too-short rear end ratio of the car, which was 4.11:1. Combined with the Aisin AR5 transmission ratios, the 23-inch diameter tires, and the 6500rpm rev limit of the Ecotec, I essentially would run out of gears way too fast. First gear was essentially useless, and at the Autocross I was running out of second gear at critical times. In the US (where I live) there are essentially two gear sets available for the NB (second-gen) Miata diff, 4:11 and 3.9. After some simple spreadsheet work, it was clear that even the 3.9 was going to be too short if I swapped it in. The good news is that Mazda did make a 3.6:1 rear end gear set. The bad news is that it was sold only in Japan and Australia. Good news is we found a seller on eBay down-under and, after a couple of weeks of shipping transit, had a hardly-used gear set delivered. We took the car apart and dropped the diff off at a local differential shop to swap in the gears, which was finished this week. The car is now back together with the new gear set, but still not quite drivable....

...The reason it's not drivable, is we took the seats out and dropped them off at another shop (upholstery) to get recovered. I looked into simply buying new seats, but the incredibly tiny cockpit of the Bugeye means essentially that the current Paddy Hopkirk seats are the only ones that will fit. Ergo, re-upholstery time. Still waiting for the shop to finish up the seats so that we can re-install and make the car drivable again. I'm really excited and hopeful the new gear set will make a big difference.

Finally, terrible news with a silver lining. An elderly fellow gearhead in my neighborhood passed away following surgery a couple months ago. He was a really nice guy and a serious car and motorcylist guy who had some pretty amazing fab and machining skills. Long story short, his widow is selling off some of his shop tools, and she asked if I was interested in anything. Well, I am. In fact, I'd love to basically buy all his tools, but there's this pesky little problem of my limited tool budget. In the end, I picked up a few things, including an Evolution chop saw and an Enco 36" finger brake. I will likely go back in the future for a few more things, but the key purchase this week was his Millermatic 252 MIG welder. I've been getting by via a combination of my little Lincoln 110VAC flux-core buzz box and the outsourcing of quality welding to guys like my friend Joe. The new machine I bought is a serious step up in capacity, quality, and abilities, so I'm hoping to improve and hone my skills accordingly and do justice to my dearly departed neighbor. RIP, Ron.

End of the Buzz

If it's not been obvoius in past posts, I really love the car. It handles great. It has more than enough power throughout the entire rev range. It's a joy to drive. It gets plenty of attention. Etc...

...but until recently, it was also kinda annoying to drive. See, there was a vibration-- no, scratch that. There were about a dozen really aggravating buzzes, rattles, shakes, and resonant sheet-metal-shake-your-eyeballs-out noises that ruined otherwise perfectly great drives....

...so, we've spent the last month slowly-but-surely tracking down noises and squashing them.

The biggest culprit was simply all the sheet metal on the car that would buzz at certain speeds, usually when I lifted off the gas around 4000rpm or so. Solutions we applied included glueing fire blanket material to the backside of these various offending locations. We also added a heat shield to the underside of the bonnet over top of the turbo and exhaust, and included insulation there, too. Plus we crimped down the headlight buckets to form a tighter grip, added rubber gaskets to the doors, intercooler interface to the bonnet, installed a boot on the shifter, etc... Well, you get the idea. 

This week, we'd gotten rid of ninety percent of the racket, but one loud buzz remained somewhere toward the back of the car. So, while I drove up and down the freeway frontage road, Joe risked life and limb, crawling all of the car, listening and applying pressure to potential noise sources. Again, long story short, we traced the last big buzzing source to the rear-most body panel that would intermittently touch the old bumperette mount behind it. A clamping bolt was quickly installed and, voilá, problem solved. 

The car is still a joy to drive--and it's relatively quiet, too. Well, that's if you define quiet as the wide-open throttle symphony of the 2.4-liter turbo spooling up. Love it!