The Miata experience: his and hers.

So, how did the NA compare to the ZL1?  

On Configuration 5, things weren't all that far apart...  the NA went 2:07.8, and ZL1 went 2:04.9... just under 3 seconds.  Not bad considering the Camaro's 35mph advantage on the front straight...  The Miata mostly kicks it's butt on corner entry, and mid-corner speeds however.

Even on the faster Configuration 1 we ran on Saturday, it was under 3 seconds, with the ZL1 at ~ 1:53.9 to the NA's 1:56.7.  

I didn't do a detailed time comparison for Config 1 since the only difference is the elimination of a right-left-right combo after the straight, leaving an 'isn't straight' that runs downhill into the kink and then uphill over a blind crest to the hairpin.

After the apex at the end of the straight, it's full throttle through that whole section for the Miata.  Not for the Camaro...  Terminal speed into the braking zone for the hairpin is within ~6-7mph.

All in all, a great weekend.  We really like this track, definitely our favorite track in AZ.  

Minor garage tinkering, since no car related stuff going on this week...

Made mounts for my workbench for my reloading presses, which I drug out of the darkest corners of the shed.  Not that I can get any components to load anything right now anyway...

NA is back in the garage for inspection/prep for our last event of the year...

Looks like the aero held up without any major issues through a full weekend.  I'm considering adding lateral bracing between the mounts, as I'm seeing some very very minor sag in the center.

In other news, things are happening... slowly, but happening...

Yup, turbocharging the NA is going to be the main project for 2021.  Parts collection is ongoing, and the intercooler just arrived.  Vibrant 12800...

Not bad for $170...

Short term plan is a GT2560R and tuning for ~220hp on the current engine.  Long term plan is building the spare engine with rods/pistons to allow later tuning to ~260-280hp.

The other major project for 2021 is a full cage, and I have stuff incoming to facilitate that project as well.  I'm about a year behind on my plans for a cage, and I want to get it done before the car goes on track with 200+hp.  

My only Black Friday sale order this year...

I'm kind of amazed the car still has a stock radiator on it at this point, but with the coolant re-route, I've never had an issue with temps.  The turbo will definitely put a lot more stress on the cooling system, so I decided to step up to the Supermiata crossflow radiator.  This thing is a work of art...

I was tempted to install it for the track next weekend, but don't really have the time, and it's not necessary so it can wait.

Decided to add a cross brace between the splitter brackets...

Just some aluminum angle to stiffen things up a bit.

Also has the benefit of supporting the bottom of the ducting...

Car is washed and fueled up, ready to go back in the trailer.

Another box arrived, this time from SWAG again.

Billet roller dies for the tubing roller to improve performance for building the cage when the time comes.  The HF roller factory dies use set screws to hold the drive die on the axle, but only three of them, offset such that the die 'wobbles' on the axle.  This makes it very difficult to get a straight bend in the tube.  I got away with it on the 1" tube I used for the bumper supports, but the 1.5" DOM for the cage will be far less forgiving.  The SWAG dies use a keyed axle on the drive die to eliminate the wobble and give a straight bend.

Last event for 2020 yesterday...  Arizona Motorsports Park, weather was perfect!  Sunny with highs in the low 70s and no wind.  

Had a really fun day, even though I didn't set any personal records.  My personal best (1:54.8) came on this track in March of 2019, and I'm still running the same tires, so I think a fresh set in the spring may give me a new PB, as the car has improved, and I think I have a better handle on the track.

First session I went out behind a Spec 944 driven by one of the track instructors.  Spent a couple laps reeling him in, including my fastest of the day, only to be caught by a group of high HP cars just as I was ready to pass him.  It took another two laps to sort that out, then I had to reel him in all over again, which I did, and passed him on the last lap.  Great session, and my quickest of the day with three laps in the low 1:56s.

Unfortunately, things got slower from there, with lap times slowing through the day.  Looking at the timing results, the same thing was happening to everyone so I stopped worrying about it, and just went out to have fun.  There were a bunch of Miatas, and I tried to get out with the Miatas in my group.  The next session I got out with these guys:

And we had a great session!  I started out behind the 59 car, and followed him for a while, then passed and followed the 5 car for a couple of laps before passing to end the session.  I picked up a couple of things from each of them, both were great drivers, and we talked about lines after the session.  Driving closely with these guys really increased my comfort level being close to other cars, and the high HP train in our group never caught us, so we were able to play uninterrupted.

More Miatas in the crowd:

My wife was out with the 'intermediate' street group, and it was full of high HP hamfists... and it seems like they get more aggressive at every event.  I'm not sure how to solve this.  It should be the appropriate place for her to run, but it seems like more and more idiots are showing up that don't have any common sense or patience on track.  Nevertheless, she had fun, which is all that's important.

So, here's the technical review:

The aero improvements DEFINITELY worked.  Fastest lap at this event was 1:56.1, with a predictive best of 1:55.4.  In March 2020 best lap was 1:57.8, and my timer did not predict a better lap so that was it.  As I noted above, personal best with the pre-aero setup was 1:54.8, but that was on brand new Toyo RRs, the same tires I am currently running.  Yesterday was the 7th event day on these tires.

The real proof is in the terminal speeds on the straights.  I wasn't able to get a good handle on this at our previous event at INDE Motorsports Ranch because of the 20-30mph headwinds.  But here, the weather was perfect so I was able to directly compare data.  Here's the terminal straight speeds from March 2020 (Pre-aero in black) compared to yesterday (post-aero).  The aero is the only change to the car between the data sets.

The improvement was very consistent.  I've never hit 100mph on the main straight at this track, and yesterday it was very consistent, even hitting 101mph on one lap.  Big improvement on the short straight after the carousel turn I attribute to better drive out of the corner due to the aero.  The car was much more stable through there, and I had a couple of comments from other drivers about my speed through the carousel.

What I didn't see was a definitive improvement in overall corner speeds.  There's a few things going on here.  First, I don't completely trust my cell phone lap timer app to parse data at that level.  Sometimes the GPS tracks shown are inconsistent with my known lines, and show variations in speed that I believe are due to the sampling rate of the GPS.  Additionally, tires are getting older, and conditions deteriorated through the day.  Finally, the additional straight speeds required adjustments in corner entry that I haven't fully worked out.  From what I can pull out of the data is that corner speeds aren't dropping significantly, so I believe there is improvement there.  The car feels great, and is definitely more stable in several corners where things were a little loose and more on edge previously.

Hopefully, I can get new rubber on the car in the spring, and we'll see what it's capable of.  And, it's time for me to step up to a real data system. 

Final note... the organizers set up scales, so for the first time I was able to get cornerweights on the NA.

I have no experience cornerweighting a car, but this gives me a starting point to do some research and see what can be improved there.  

It also gave me a weight for the car of 2104lbs, once I subtracted my weight.  The previous weight I was working from was 2050lbs... changes since that weight included removal of the power steering, the drop floor modification and the aero.  The previous scale was a local scrapyard, so accuracy is quesitionable, and I would not have expected the modifications to add 55lbs... should have been nearly break-even.  More food for thought... 

Holiday bump...  out for a romp today with some friends... 

Quick tow rig project...

I hate running boards.  Hate them.   That said, after knee surgery last year, I knew I was going to need them.  If only to avoid another knee surgery in the future.  Plus, my wife would no longer be traumatized every time she had to climb into the truck.  

After looking around for quite a while, I had finally settled on some Mopar accessory boards that I had actually looked at in person at our local dealer.  I never pulled the trigger because they were $600+...  And then I came across a thread here on GRM where someone mentioned iBoards, which also go by iSteps.  Like the Mopar boards, they're nice and simple, don't look like a wanna-be Kenworth accessory, and attach with something other than sheet metal screws.  And under $200...  Thank you GRMrs!

Ordered off Amazon and they showed up yesterday, so this morning I installed them.  Less than two hours start to finish, and that was taking my sweet time.  Very easy install!

The parts:

Installed:

I'll report back after using them a while, but I think they'll do the trick.

Over the Holidays, I gave a great deal of though as to what's next for the NA.  As much as I want to mash the go pedal on the turbo, I've decided safety needs to come first, and a full cage is at least a couple years overdue.

First things first... I didn't yet have a set of 1.5" dies for my bender, so those are ordered.

Next was the thing that had been complicating the cage issue in my head for a while:  a race hardtop.  While I could certainly build a cage under my current hardtop (an OEM style Snugtop), a race top would allow slightly more room for the cage, as well as the benefit of significant weight reduction up high.  The sticking point had always been the expense... there was always something else to throw $$$$ at, especially when a significant portion of the cost is shipping.  The flip side is hardtop prices are really high right now, so I should be able to offset 100% of the cost of the race top.  I should also be able to sell the current rollbar to offset some costs as well.

So, the top is ordered.  5-6 weeks.  Now the waiting begins.

In a few weeks, I'll get the car back in the shop to pull the rollbar and start prepping for the cage install.

Under the continuing category of small projects progress, I had to pick up a new Argon/CO2 tank for the MIG today.   While I had the welding cart out I finally got around to making some PVC rod holders.

Minor rant:  Cart came with brackets drilled 2x for 1.5" and 2x for 1.25".  Short of using aluminum tubing, modifications were required for the PVC pipe to fit.  It would have made more sense to just drill the brackets for pipe sizes.  I was able to use 1" pvc for all four, but it required some modification to the smaller holes.

After a great deal of internal debate, I've decided to sell our Bronco in the furtherance of making some changes to the fleet that will better reflect our needs as we close in on retirement.  Kind of sucks, 'cause I thought I'd never sell it, but I think it's the right decision...

1992 Bronco up for sale...

The Bronco drove away with its new owners today... sold to the first person that looked at it.  Sad to see it go, but not quite as bad as I thought it would be.

New owner is a little older than I, retired Ford mechanic and service writer and long time desert racer, so I know it's gone to a good home.

Another big change coming soon... stay tuned.  

So, the other shoe dropped today.

Having something like our Bronco was a required backup for my wife having an insane DD like a ZL1.  We do get snow here in the AZ mountains, and often times have to go dirty places that aren't appropriate for low slung sports cars.  The Bronco was also an important component of our traveling roadshow when the mission was getting into the back country, as opposed to going around a racetrack.  So we needed an appropriate replacement

And then there's the ZL1... which we've had for a little over two years... what an amazingly capable, totally bonkers car.  It still amazes me you can buy something this nuts, with a factory warranty that covers track driving.  Crazy.  Anyway, as much as we love the car, it's just stupid on the street... you really can't use any of its incredible potential.  We did have our fun with it on the track, where it was still bonkers fast.   As much fun as it was, we both have more fun driving the NA, and it's a lot cheaper to track.   Long story short, we experienced the insanity of the ZL1, and LOVED it, but we're ready to move on...

For the replacement, I wanted a reduction in the overall fleet, so it really had to replace both the ZL1 and the Bronco.  I know, you're saying "WUT??"  What that meant for us is something daily driveable, with modern features to keep SWMBO in the lap of luxury, but capable for the kind of winter weather, and back country driving we do.  And it had to be towable 4 down behind our camper.

And, the winner is.... the 2021 Jeep Grand Cherokee Trailhawk

The new Bronco might have been a contender but between lead times, first year issues and Ford dealer gouging it wasn't really an option.

Jeep was really the only game in town for off-road + flat towing capability, so we looked at Wrangler, Cherokee and Grand Cherokee.   We rented two different Wranglers when we were in CO, and while they're the best for serious off-road, they're the worst for on-road driving.   Wranglers are also by far the most expensive for what features you do get.  In the Cherokee and Grand Cherokee, we were specifically looking at the Trailhawk package for the off-road performance.  The Trailhawk package meets our needs almost perfectly... we're not going rock crawling, so the extra capability of the Wrangler really wouldn't be worth it for us.  The Cherokee was nice, but a little small, and missing some content compared to the Grand.  The Grand Cherokee offered the right luxury features at a decent price point, and with the Trailhawk package has plenty of off-road chops for what we want to do.

So, we reduced our fleet by one vehicle, and gained a more practical daily for SWMBO that will double as our backcountry explorer and dog taxi.  With the ZL1 gone, I can focus our track efforts on the NA.  And we still have the NB street car, which will finally get some long overdue attention so it can be the nice day roadster it really wants to be. 

Since I woke up wide awake at two in the morning, I ordered a bunch of Miata parts. 

The NA is getting new wheel hubs and bearings...  I've been wanting to upgrade before the current set shows any significant wear, and I've had a set of SadFab rears sitting on the shelf for a while.  Those are based on an MRS hub, which is quite a bit beefier than the Miata hub.  I finally pulled the trigger on a set of Miatahubs for the front.  I know they're the 'forever' solution, but geez that hurt...   

The NB is going to be getting the hand-me-down wheel hubs/bearings from the NA, and a soup to nuts brake job. 

I got a shipping notification for my bender dies, so they'll be arriving next week.  Not that I'll be diving into the cage before the new hardtop arrives.  The hub swap and brake job should keep me busy until then...

Interestingly, the Grand Cherokee takes up almost exactly the same real estate as the ZL1 did... literally within 2" in both length and width.  So it fits in the garage.  I did have to recalibrate the tennis ball assisted parking parking mechanism.

The only problem is the tailgate hits the garage door when fully open.  And since it's automatic, it can't be opened/closed with the Jeep in the garage.  That's kind of a problem.

The extra wheel sets for the ZL1 went up on CL today... hopefully those go quick.

If you backed the jeep in would that help with the tailgate issue?

In reply to jfryjfry (FS) :

Pretty sure it would just hit the bench...  plus, there's no way my wife will be backing into the garage... 

Considering you were replacing the Bronco and the ZL1 I thought for sure you were going to buy a Grand Cherokee Trackhawk and then throw some BFG KO2's on it.

In reply to docwyte :

Now that would be something! 

Brought the NA home today to start working on the several upcoming projects.  With my bike moved into storage for now, it fits in the garage.

Jeep seems happy to share so far...

I started working on a template for the curve on the main rollbar hoop, one of the features I want to build into the cage to provide as much room as possible.  First up was making a template of the inside curve of the hardtop.

Next was transferring the positive template to a negative template for curving the tubing.

This one will be for practice with the roller and bender, as I don't have the race top yet, and the profile may be slightly different.  You can see how much space will be gained in the center of the hoop by arching it.

For your track timer / data logging, you can get a multichannel GPS with 10Hz update rate, connects to your phone via bluetooth.  I have the Dual Electronics XGPS150 (available on Amazon) and it works amazingly well.

Installed the Supermiata radiator this morning.  Quick & easy, though it required a run to the parts store for a longer overflow hose and some spacers and longer M6 bolts to locate the fan properly.

Overkill for now, as I've never had a temperature issue with a stock type radiator, but it's futureproofed for later mods.  And it's a thing of beauty.