1997 Mazda Miata: Two Valve Stems, But Why?
February 13, 2013
I first noticed that the alloy wheels on our Miata had two valve stems when we last tested it and I intended to do a little research to find out why.
1997 Mazda MX-5 Miata: Fuel Economy Update for January
February 4, 2013
The plus side about building an engine offline (more info here, here and here) for Project Miata is that it avoids prolonged downtime for the car, so we can continue to use and enjoy it in parallel. Of course, this also means your hair's not on fire to slam the engine together and slap it in the car. It's been on the engine stand for several weeks, gradually being prepped as time allows.
In the meantime, during the month of January we drove Project Miata, our 1997 Mazda MX-5 Miata, about 600 miles. It uses some oil, some of which is oozing out of the tired old valve cover gasket and making for a grungy engine. Otherwise, it just runs and runs. During those four weeks the little green TicTac averaged 23.8 miles per gallon of 91 octane premium.
Not bad for a modified first-gen Miata.
Jason Kavanagh, Engineering Editor @ 140,650 miles.
Worst Fill MPG:9.6
Best Fill MPG: 26.5
Average Lifetime MPG:22.1
EPA MPG Rating (City/Highway Combined): 20 city/26 highway/22 combined
Best Range: 292.2 miles
Current Odometer: 140,650 miles
Note: Cars are sometimes refueled before their fuel tanks are nearly empty. As such, "best" and "worst" fuel economy entries above are not necessarily the result of an entire tank's worth of driving.
1997 Mazda MX-5 Miata: Door Bar Conflicts With Dead Pedal
February 1, 2013
I've never really cared that the door bar on our long-term 1997 Mazda MX-5 Miata project car hinders entry and exit. Once again, I chalk it up to the character of a project car.
But the last time I drove the project Miata, I found that my left shoe kept hitting the door bar on its way to the dead pedal after clutch use. Not a huge deal, but the door bar leaves minimal width between it and the clutch pedal.
1997 Mazda MX-5 Miata: Aftermarket Seat Tips, Version Two
January 21, 2013
After living with our modded 1997 Mazda MX-5 Miata and its aftermarket seat over a weekend, I realized I left out a couple of key seatbelt-buckling tips.
I failed to mention that in order to feed the belt through the seat hole on the center tunnel side, you actually need to position your butt up on the left-side seat bolster so that your right leg is out of the way. No biggie, just not your typical seat-belting method, eh?
The other extremely helpful tip is to slide the seatbelt receiver back slightly, so that it's closer to vertical. This makes it a straighter shot for the belt.
One last tip. If you're hopping into the Miata at night, just don't be in any kind of a rush. I found out (when I was in a rush in a very dark parking lot) that the interior light doesn't work. Not sure why I've never noticed this before. But it made it even more of a challenge to snap the belt into place, since I couldn't see anything that was going on in the extremely tight space between that heavily-bolstered seat and the center tunnel. Plus, you can barely even squeeze a hand in there.
But you know what? After a couple of fumbling runs, I actually got reasonably good at the whole process. Even in the dark. Some might call it a nuisance. I call it part of the character of a modified car.
Mike Monticello, Road Test Editor @ 140,508 miles
1997 Mazda MX-5 Miata: Ride Quality
January 17, 2013
Considering the level of handling our 1997 Mazda MX-5 Miata possesses, the ride quality is actually not that bad. Believe me, I'm not saying this modified car rides down the road like it's on a bed of pillows, but for a machine that pulls 1.03g around the skidpad and 71.8 mph through the slalom, yeah, I'll put up with above average stiffness and some harshness over small bumps.
Unlike a lot of modified cars, there is some compliance here. It doesn't try to bounce you up out of the seat and drive your head into the roof over large, fast bumps. Chalk it up to spot-on spring rates.
Also, and again unlike a lot of modified cars, the Miata's suspension is quiet. No squeaking, creaking or clunking noises coming from the chassis here. This is suspension done right.
Which is not to say Project Miata is rattle-free. Nope, there's more than a few odd, and occasionally annoying, rattles and squeaks emanating from the tired interior.
Mike Monticello, Road Test Editor @ 140,445 miles
1997 Mazda MX-5 Miata: Aftermarket Seat Tips
January 16, 2013
This was my first stint in our 1997 Mazda MX-5 since on-site Project Miata guru Jay Kavanagh installed an aftermarket racing seat. As such, I now have some key tips for anyone driving this car.
Tip Number 1
Be sure to remove everything from your pockets before getting into the extremely restrictive confines of the seat. That means everything, but particularly that cell phone in your front pocket. Because once you're in this seat, and especially once you're buckled in, there's no getting anything out of your pockets. Ever again.
Not to mention the fact that, apparently, Dan Frio doesn't appreciate people pocket dialing him.
Tips Number 2 and 3
Before you try to buckle yourself in, gather as much seatbelt slack as possible (this tip courtesy of JayKav) prior to slipping the belt through the hole in the seat.
But even more important, especially for those of us short of leg, be sure to buckle the belt before you move the seat into its proper forward position. Skip this last step and you'll be hard-pressed to pull the belt far enough back to clasp it into place.
Follow these tips and this seat won't seem like such a hassle, leaving you to revel in its unbelievable lateral support. Just the thing for canyon runs and track days.
1997 Mazda Miata: 140,000 miles
January 11, 2013
Even though the number 225,308 is much more impressive than 140,000, the bigger number is in kilometers. And since we live in America, we hate the metric system. Take that, easy to use and accepted worldwide system of measurement!
Anyway, our 1997 Mazda Miata has defied the odds, as well as some friendly wagers around the office, and trucked through 140k on the odometer.
At this point in its life, our Miata still sports a Rotrex supercharger kit, Fat Cat coilovers, really nice 949 Racing 6UL wheels, Hankook Ventus R-s3s and a Blackbird Fabworx six-point roll bar. It might burn a little oil, but it's still a total rip.
Kurt Niebuhr, Photo Editor @ 225,308 km
1997 Mazda MX-5 Miata: Screeeal
December 28, 2012
Cold engine, a bit of throttle and a whole lot of belt noise. Project Miata has been relatively trouble-free given its age, hard use and modifications but it (literally) sounds like it's time to check the accessory drive belt tension.
The Kraftwerks supercharger kit uses a Gates belt. It's racy blue and has a heavy dose of Kevlar in its construction. I know these fancy belts make more noise than standard off-the-rack belts, but what I heard that day was clearly a full-on belt squeal a la 1982 Oldsmobile Cutlass Supreme. So, no, there's no "ah, those blue Gates belts all do that" this time around.
Jason Kavanagh, Engineering Editor
1997 Mazda Miata: To Laguna and Back
December 07, 2012
Remember that blog about a few of us going to Laguna Seca for a track day? Yeah, well I was one of those guys and I happened to be driving our Miata for the duration of the trip.
I've got a brace of photos, some in-car and roof mounted videos as well as some insight into the car, the drive and what it's like to get completely psyched out by a one way ribbon of asphalt.
If there's anything you'd like to know about the trip, the track or the car, let me know and I'll do my best to answer your questions. Until then, stay tuned. I'll have the first in a series of blogs after December 17th - after I figure out how to edit video.
Kurt Niebuhr, Photo Editor @ 139,580 miles
1997 Mazda MX-5 Miata: Chasing The Squish
November 29, 2012
An upcoming (likely floody) track weekend lit a fire under my backside to re-tackle Project Miata's brake pedal feel.
As mentioned many times previously, its pedal is rather soft. Always has been. Moreso than in any of the countless Miatas I've driven over the years. It's not that scary squishy pedal you get when there's air in the lines, it just has a very gentle ramp into actual braking force. And that's despite numerous brake bleeds (including cycling the ABS unit) and several pad changes. The calipers are in good shape and function normally, there are no leaks, pedal free play is about one millimeter, and it has stainless braided lines. Full ABS braking capability is still available when called upon.
That leaves the master cylinder.
1997 Mazda MX-5 Miata: Rotaries Are Good For Something After All
November 27, 2012
We're not swapping a rotary into Project Miata, but we are in a very small way taking advantage of its bigger brother's infamous thirst.
If your Miata is turbocharged or supercharged, its fuel system is flowing a significantly higher fuel flow rate than stock. Fuel flow rate scales (roughly) proportionally to power -- increase the power by 50% and you increase the fuel flow rate by 50%. And all of it passes through the filter. From a filter design standpoint, higher fuel flow rates require more filtration media, which are those pleats of paper wadded up inside every filter canister. Manufacturers don't like to put any more filtration media into a filter than they need to because, hey, that stuff costs money.
So what happens when you put 171 hp worth of fuel through a 100-hp filter? Hard to say without measuring, but its a good guess that the pressure drop of the fuel across the filter increases significantly. Higher pressure drop means the fuel pump has to work harder than it really needs to.
I have no idea when the previous owner of Project Miata last replaced the filter, which means it was time to replace the filter. In doing so, I wanted to find a filter that at least matches our modified car's horsepower and looked like it can be made to fit with minimal effort. Effort sucks. Being savvy with part interchanges is awesome.
1997 Mazda MX-5 Miata: DIY NB2 Coil On Plug Option
November 23, 2012
If you're installing an '01-'05 Miata engine (aka NB2) into an earlier chassis, one of the things you'll have to deal with are the coils. The NB2's VVT hardware precludes mounting the earlier coils in the usual spot at the back of the head. You can adapt the stock NB2 coil-near-plug hardware to the earlier harness, but these coils are generally considered the weakest of the NA/NB coils (themselves not much to write home about), so if you're planning on boosting you may find that you'll need some kind of other solution.
Beyond the jump is some kind of other solution.
