Finally! Time to go stretch the car’s legs and see how it runs. This weekend was the first big shakedown. This is pretty much a completely fresh build at this point, and so you have to expect to discover issues and there's a long teething process as issues are sorted out, items fixed and improved, etc. once it’s being used at the race track. This weekend was all about getting the car out there and running it as much as possible to discover those issues and to take home a long but focused to-do list for how to improve the setup.
Saturday was Mazfest at Auto Club Speedway and I had a great time showing the car when I wasn’t on track.
On-track was special, after this much time building the car it was great to just feel the thing doing what it is built to do. There is a lot of power on tap and the engine is super smooth and worlds better than the old turbo setup. Torque is just always there if you want it. I'm delighted to find the car is still very "Miata" with great balance and drives just like it should just with much more motor attached to the right pedal. That was the biggest goal with going with this engine package over alternatives that might weigh a bit more.
Here’s a run-down of notes on each system and any issues that did spring up.
- Engine (max temp 225 water / 265° oil): no issues to report. Ran like a dream, makes power everywhere. Currently running with no oil cooler, just the factory filter housing. Oil cooler will bring oil temp down a good chunk once I have that in and working.
- Transmission (max temp 200°): Grinding on upshifts. I believe it’s a pedal/rod length issue. Bled the system after 1st session with no effect. Drove around it the rest of the weekend by trying to be VERY patient on shifts to let the rpms drop to where they needed to be on the next gear… which was somewhat successful. Gearing is good. Used 3-4-5 at this track which has a really low speed ~50mph tight right at the end. 3rd pulled right out of it, I won’t ever be using 2nd on a road course.
- Differential (max temp 180°): puking fluid out of the vent on top. V8R says running a breather line will fix this. Otherwise, the limited slip characteristics feel great.
- Power steering (max temp 190°): leaking fluid from the cap. We’re suspecting it’s from high-G right-hand turns which effectively submerges the left/lower side of the non-sealed cap. I’m implement a fix in the next couple days. Steering feel with the NB power rack is good and I’m much less worn out at the end of a session than with a manual rack. I think I’ll be keeping the power steering for a while.
- Ergonomics: new seating position and controls are all perfect. I did accidentally hit the fuel pump switch to off when shifting once. Might need to move the switches or add a guard.
- Display dash: I’ve already forgotten how I lived without one of these. The dash is set up to monitor all the temperatures and pressures without me having to do anything. If something is amiss, it lights up a warning light and lets me know. Otherwise, I just drive.
- Suspension: the spherical bearings and Feal 442 shocks are butter. I haven’t even begun making adjustments here yet, just set compression and rebound to dead center of the available range and left them there while I focused on everything else.
- Brakes: The V8R/ST four wheel kit has some serious stopping power and is easy to modulate.
- Powdercoat: powdercoating has a “squish” in the coating that prevents proper torque on bolts. I lost a spindle to caliper bracket bolt on track which prompted checking every bolt on the car that was in a powdercoated surface. Several had loosened. The rest of the weekend I re-torqued bolts after every 2 sessions. Will be adding split lock washers to most of those bolts this week since the lock washer will cut through the coating.
A great thing about the temps listed above for steering, diff and transmission is this confirms what we suspected - these items are all way under-stressed in a small lightweight Miata. Zero need for diff or transmission coolers.
Joe working the pedal while I bleed brakes:
Chatting with Sean about something. Probably about how something tried to fall off the car:
It was great fun to see so many friends at Mazfest who were there for the track day portion or who just came up to check things out. Being back out on track in my own car with fellow Roadster Cup guys felt great:
Spent all of Saturday with a passenger riding along and sorting out issues, and got absolutely no clean laps without traffic but I still ended up setting the fastest time by a Mazda at Mazfest with a 1:11.x.
Quite honestly surprised by how much pace the car had out of the box with zero time spent on dialing things in. Since it was still running well I signed up for the Redline Time Attack competition coming up the next day and grabbed a hotel for the night.
Redline Time Attack
Sunday morning first practice session in the cool air I went out with no passenger and did a 1:08.763. That is a new lap record for a Miata at this track (Auto Club Speedway Infield) by a gap of almost 3 seconds.
Time sheets after the practice session revealed that not only was it looking like I could take the win in my Limited Rear Wheel Drive class, I was actually within range of contention for the top overall time with the unlimited cars. There’s no way I could ignore that carrot dangling out in front of me so “I’m just testing things this weekend” went out the window at this point and it was game on. I did a little research around the paddock to scope out the cars that were at the top of the time sheets with me:
At the top of the sheets, this 500hp BMW M4 built for NASA ST1 competition running in Unlimited RWD:
Bulletproof Automotive's 750hp GTR in Limited AWD:
Time Attack veteran Amir with a 660hp aluminum V8 swapped E36 M3 in Unlimited RWD:
In true Time Attack fashion, Redline has just two Time Attack sessions where it all counts. Only three laps in the session, do or die time. Cars are pre-gridded by lap time from practice so I was third in line behind just the GTR and M4. Temps had climbed
That lap took 1st overall by a gap of just 0.08 seconds ahead of the M4.
By the second afternoon time attack session temperature had climbed a lot and some teams didn’t run because they knew they wouldn’t go faster. The GTR and M4 both went out to try to take the top spot. They both went slower. I did a 1:08.8 again, so that lap would have been even faster in the cool morning.
SO... first shakedown weekend with the car… fastest Mazda at Mazfest, 1st place Limited RWD and Top Time overall at Redline Time Attack, and a new Miata Lap Record.
We’re on the right track here. With some more track and tuning time this car is going to rip.
Great Miatas @ MRLS event! I'm working on gettings some pics/vid together from that. In the mean time, there were a couple things that sprang up at ACS that I needed to solve, and now after running MRLS I can confirm the fixes worked so I'll cover those..
First up, the differential fluid was exiting the vent cap on the top of the diff, leaving a very traceable mess on the underside of the rear subframe and down the side of the diff. A quick check with V8R confirmed they've seen this happen and fixed it by replacing the vent cap with a hose barb fitting and running a vent line up higher.
Vent cap (right) is just removed with pliers. It's being replaced with the 1/4" NPT to 3/8" barb fitting on the left:
Tapping the hole for the fitting is a treat when the diff is up in the car. I'd call changing the vent config on the getrag a must-do item so if you haven't installed your diff yet, just do this now before installing everything:
Fitting and hose installed with a loop in the hose:
If the vent tube mod works, we can just run the hose to the open air. But since we didn't know yet if it would work, I wanted to run the line to a reservoir to catch the fluid in the event that it was still losing any. I repurposed a Wilwood brake fluid remote reservoir for the task, with a barb fitting installed in the cap and a hole drilled in the top of the reservoir to vent pressure:
After 3 days at MRLS, the reservoir is still dry so that's confirmed that the vent hose is working perfectly.
The second fluid that was trying to exit the vehicle was the power steering fluid. This one was a bit trickier to diagnose but I came to the conclusion that because the reservoir cap was a vented/non-sealed design, in high-G right hand turns the fluid was being pushed against the side of the tank and effectively submerging the side of the cap, and thus exiting via the cap's vent.
The cap needed to be sealed. I didn't take a pic of this but sealing the cap involved drilling out the spot welds that held the three pieces of the cap together, removing the vent ring, welding the two remaining pieces of the cap back together and then ordering a second cap to scavenge a second O-ring from and doubling up the O-rings under the cap to take up the height of the missing vent ring and seal to the reservoir neck.
With the cap sealed, the tank still needs a way to vent pressure. Drilled/tapped a small 1/16 MPT hole in the upper left hand corner of the tank and ran a vent line off that, with a loop to stop fluid from passing down the line:
Same as the diff vent line, to confirm the modifications were working as intended, I repurposed another brake fluid remote reservoir to serve as a catch can:
Same story, 3 days at MRLS and the reservoir remained dry. Fix worked.
2017 Miatas @ MRLS! The final week of prep before the event there was a lot of crunching to get things done in time. Lots of little details here and there, and finished it up with completing the color scheme on the car which included wrapping the new hood and adding details on some other panels.
Made the pilgrimage up to Laguna Seca and had an awesome three days up there. In short, more confirmation that the car has lots of potential.. this isn't the type of event for putting down fast laps, we're mostly giving rides and making sure to play nice with all the traffic out there, but Sunday morning I did get one fun clear lap. I wasn't pushing things, just having fun chasing Jess Heitman in his V8 Prod car, waiting a month between upshifts (because we're still chasing the shifting issue) and still that lap was good for a 1:38.6. On street tires. I wasn't even thinking it would be a quick lap until I crossed the start/finish and saw it come up on the AIM.
Holy tire deflection batman!
And footage of a fun lap! The sound of that motor echoing off the pit wall going down the front straight is just rock and roll. But the best part was getting my dad in the car for a couple laps and his reaction at the end:
I did have a sound issue over the weekend. Car hit 107db in the cool morning air XD so a track-side fix was needed. Brian had the great idea to rotate the passenger side muffler on the V-band so the outlet was pointed at the ground instead of straight at the sound booth (which is located at right side of the track between turn 6 and 7). A little Macguyver action with a coat hanger and things were adequately suspended from the mounting points. Sound check confirmed this dropped output to 101-102 db at the booth and I ran it this way the rest of the weekend:
Superlap Battle prep is in full swing. Since MRLS I've been in the shop every evening and weekend (except when I went up to BFW last weekend to lend Moti a hand on Creampuff). Will update as I get things wrapped up more, but for now a teaser.. some material arrived today:
Superlap Battle is two days away! Since MRLS, there have been many updates. Since I'm currently running around like crazy getting the finishing touches done on both my car and the shop's ND before the event, I'll have to keep the update brief for now.
CCP Fab composite doors with my special request for a kevlar inner layer to help with debris protection. Very light, 5.55 lbs per door without hardware/latches. Dropped 41.7 lbs total from the car swapping from my cut up factory doors. The aluminum rod was added to help with flex:
Beginning to add more of the aero package I have planned for this car, new side skirts/barge boards and rear tire spats fabbed up to control the air down the side of the car:
The apparent simplicity of these when you look at them really belies the complexity of making them. There are several pieces that go into the full thing, not to mention a full array of brackets for mounting and completely re-engineering the way you put the car on a lift or jack stands. The jack stand points are now these little removable units that have threaded tops that screw up through the barge boards in to receivers welded to the car so that when you remove them there's only a nice flat surface left:
Also needed a jack point to lift the car from when at the track. The barge boards are too low/stick out too far to put a jack under the car. Moti recently solved this same thing elegantly on Creampuff with a receiver welded to the cage and a removable lift arm and I mimicked that design, but with mine located on a more rearward cage point since my doors have to swing open:
The receiver sits flush with the outer door face when the door is closed. Don't have a pic of the removable lift arm but it slides into the receiver:
Further cutting weight, Buttonwillow has no sound limits. No need for extra weight in the exhaust for this event. Going full race car, no cat and minimal muffler. Dropped 10.5 lbs in total from the car. I will be packing ear plugs for this one.
Small titanium heat shield on the barge board:
Side of the car in the new SLB config:
Finally, adding all the downforce possible was high on the must-do list for SLB. Two weeks ago Moti and I spent 60+ hours over a weekend working on our evil world domination plans to build new next-level splitters for both Creampuff and this car. Design and mold construction took a massive amount of time, and there was only enough time to (barely) finish one splitter before SLB so we made the call that Creampuff should get that splitter.
I CAN'T WAIT for you guys to see what we have been cooking up on the new splitters, that will debut on Creampuff in a couple days. BUT that also means I'm still on my old generation splitter for this event. In an effort to maximize downforce production with what I have, with the little time I had left I put together add-on splitter extensions. Nothing advanced but it will be effective. These increase splitter total width by 10".
To help balance the front additions, the rear wing gets some "go big or go home" endplates.
Car is on deck at the alignment shop, sans splitter:
Superlap Battle 2017; the year-end finale of North American time attack.
With just an initial shakedown at ACS and a demo weekend at Laguna Seca to get the car roughly sorted out and work through initial teething, it was a race against time in the final weeks before Superlap Battle to finish and dial in as much as there was time for. I have huge faith in the recipe being built here, but always the realist, I kept expectations light. To be in contention for a podium spot at the car's first SLB would be superb. Also hovering in the shadows of this event was the chance to do something no Miata has done before; go sub-1:50 at Buttonwillow CW13. I know the car will be able to do it, but on the street tires we'll be running for Limited RWD? That is a tall order. The long-standing Miata lap record has been a 1:52.2 - that from a 400whp car on 275 Hoosiers.
This year's Limited Rear Wheel Drive lineup was stacked. SIXTEEN competitors - the most of any class this year. Porsche GT3s (yes, plural), Viper ACR, turbo S2000s, LS swapped M3s, great drivers, the list went on. This is the arena we built the HyperMiata for.
Day 1 was on old tires. With practically no prior setup time and running more aero additions here that we hadn't had at the initial shakedowns, the race for us was to get setup dialed in quickly. It was game on during the open practice session - every time in off the track we did a full setup sheet on the car and driver download - this worked great, my girlfriend would hand me the clipboard while I was still in the car and I would take a minute to go over the previous session while it was vivid in my head and note the changes I needed both with the car and with how I was driving. As an amateur driver, this proved a really valuable tool.
I had early thoughts of perhaps sandbagging if it looked like we were in the hunt for a podium spot since the turbo guys could turn up the power if they were feeling pressure early. But first, I felt it would be wise to just go out there and get a good solid time on the board during the first session that counts, because you never know what might happen and what challenges you may face later on.
First time attack session, 1:50.9. Already broke the Miata lap record. OOPS, so much for sandbagging. Even better, we were sitting in first! Change of tactics then, let's give it everything and let them chase us if they can. By the end of day 1 the sub-1:50 was in the bag with a 1:49.9!
Unofficial results at the end of day 1 had us in P1 with 2nd through 6th all scrambling for position in the 1:51-1:52 range. No point holding back now, for day 2 we swapped to fresh tires for the cool morning session, but I made the error of getting to grid late and had to go out in the back of the pack. I spent four laps carving through the field, and finally by lap 5 had clean track ahead but the tires were over temp.
Track temp was up substantially by session 2 but with good data from day 1 at these temps we dialed in what should work well and went out. I was still adjusting to what the car is capable of doing and beginning to feel comfortable with it. 1:48.7! Session 3, hottest and thus slowest of the day. Still found a cleaner line and another two tenths of a second. 1:48.5!
Session 4, the Superlap session. First flyer was feeling amazing - first time flat on the throttle from the exit of cotton corners through the right/left kink all the way to braking for bus stop. Nearly flat through the entire high-speed section of Riverside at 110+ mph. The car was magic. Then an Evo caught fire and the track was red flagged. That gave the tires some time to cool at least. We did a lap under yellow and then it was back to green. Tires felt hotter than before and it didn't feel as quick, but still set a 1:48.483!!!
Final results - 1st Place 1:48.483 No other car in Limited RWD went under 1:51, our final time took the win by nearly 3 full seconds. Further, we were only hundredths of a second off from the fastest overall Limited class time. And the previous Miata lap record? Nearly 3 seconds below that, on the street tires.
On the podium, collected the champagne, big fake check and plaque and then I miiiiiiight have yelled “Miata is the answer!” to the crowd of (mostly) non-Miata drivers
Congratulations Ryan! Your success is real testament to your ingenuity and engineering skills! Glad to see that so much hard work has paid off. Also great that you documented such a great build and in such amazing detail. Every new post had me wondering "What next, what next?" Now I am just going to sit back and wait for the full length feature movie to come out. Thanks for providing so much entertaining reading.
Jason Victoria, BC Canada Sold: 2006 Winning Blue, 2.5L, Progress springs, KYB shocks, Michelin PSS, Full GWR street exhaust. Current: 2017 Fiat 124 Abarth, Rosso red, M/T, Progress springs, Wilwood BBK, Full GWR exhaust
Got wind that Speedventures is hosting a weekend out at Chuckwalla Valley Raceway this past weekend. after the success - and also all the stress and long hours - of SLB, I figure it would be nice to finish the season off with a fun no-pressure event. Could even get some early 2018 testing in, plus CVR is just a great Miata track.
The plan is mostly to just roll the car out there in the same trim as it ran at Buttonwillow, but first I did a post-race inspection. Superlap wasn't easy on the car, there's several things that took some damage and need repairs, and a couple of those things need addressing before going to CVR.
First, the front upper ball joints decided to try to remove themselves from the upper arms. Going back through notes I realized V8R recommends tack welding these in to the arms to avoid this. Clearly, that would have been a good idea.
Took this as a sign it was time to improve the front upper arms. Switching to the V8R X-Lite front uppers. Spherical bearings throughout and track-side quick camber adjustment via shims. Also, 0.95 lbs lighter than the arms they are replacing (each).
Second, the mounting tab on each of the shorty mufflers broke. The safety wire was the track-side fix at SLB. These were made with really thin material to cut weight, clearly just a little too thin. Remaking them with thicker material today:
I don't see where you've addressed the before & after weight. I realize it won't be apples to apples since you did some cutting, but it would give us some kind of idea.
Since you weighed everything else did you weigh the engine and transmissions to compare? You said earlier that the transmission weighed more than the Miata one but since it was low & centered you weren't overly concerned, but how much heavier are the bits?
How do you like the transmission? I'm used to American transmissions being clunky. The Miata & Honda S2000 transmissions are like butter. To me the transmission is the thing that makes or breaks a car since that is your main contact with the go fast bits. A transmission that easily downshifts and doesn't require lots of your concentration allows you to be faster on the track or autocross.
Do you know if the transmission on the LF is the same as the one on the LG? I went out and test drove a V6 6 speed Camaro yesterday and while there was some "yielding" on the shifter and it wasn't quite as good as the Miata one, it was pretty darned good. But is it the same transmission as what you've got?
I was amazed at how fast that Camaro was and it was pretty nimble to for a 3400# car with a 110" wheelbase.
It's not apples to apples to just compare engine weight or transmission weight alone because there are a lot of related details that affect weights too. As an example, the Getrag differential itself is lighter than the Torsen it replaces but you also need to add the mounting kit which puts the total assembly as it sits in the rear subframe at a couple pounds more.
Thec ar is currently right at 2100. That's just about exactly 100 lbs more than it was before the swap. Keep in mind that's up against a 1.6L so compared to a 1.8 it would be a smaller difference. The interesting note is that weight balance front to rear is exactly the same as it was with the 1.6L turbo motor that was in it previously. That's because much of the added weight is in the transmission which is more centered in the chassis and a bit of it is also in the rear. That weight distribution element is why the car still drives just like a Miata, albeit with a good bit more power.
Regarding the shifter, I can't yet make a good comparison. You'll notice in my on-track vids that I am shifting very slowly because I'm still chasing a clutch engagement issue so it is tough to shift and grinds if I am not very patient when shifting. Still unknown if it is an issue with a mis-match of parts (CTS trans with a clutch and throwout bearing for the Camaro) or if it is a hydraulic issue. I'm working on getting to the bottom of it. At any rate, I have heard from a couple others that when it's working right it shifts nicely, I just can't yet say from first-hand experience.
I am using a factory ECU - it just has V8R's tune on it. We're going to be doing some work soon to switch to E85 fuel and re-tune more aggressively for even more power.
Carguy123 wrote:Also, from an autocross perspective, with that 3.43 rear end what is your max speed in 2nd gear.
The Camaro I drove had the 3.23 and hit 63/64 in 2nd.
Well my transmission and diff choices were made for road race, so 1st and 2nd gear were not even a consideration
With 7200rpm redline, 3.43 rear and 22.5" tall tire: 2nd hits 56 mph. For autocross, 3.23 could push 2nd higher but I think with the torque, targeting 2nd/3rd gear would be better than 1st/2nd so I'd probably go 3.73.
That trans just isn't designed for a direct mount. That's not a bad thing, some of the best transmissions out there in terms of feel are not direct mount. You could shorten/lengthen the dogbone in the linkage to move the shifter as needed.