Recall my recent post about the untimely demise of my MR2 Spyder’s engine during a brief track weekend. A recent visit to the guys down at DDPR gave me an opportunity to see exactly how bad the engine was damaged. I’ll let the photos do the talking.
In this last photo you see the broken off tip of an exhaust valve from the #1 cylinder. It broke right at the retainer and looks as though it was a material failure. Lesson: probably shouldn’t rely on used OEM parts in an engine producing 310hp to the wheels out of 1.8L.
The cylinder wall, close to the top of the deck is damaged from the loose valve head. There’s also some scoring in another cylinder, could possibly be from particulates being injected into the oil during the destruction going on in cylinder #1. Obviously the combustion chamber of the guilty cylinder is badly damaged on both the head and piston sides. Looks like a set of 10.5:1 pistons are in order, which should also help to reduce EGTs and also allow running slightly leaner mix as detonation wouldn’t be as big a concern.
This Saturday I went up to Motorsports Ranch in Cresson, TX for a track day with The Drivers Edge. I brought along the MR2 Spyder for only its second ever track day, last time was the 3.1 mile course at MSR. This time we’d be driving the 1.7 mile configuration, clockwise, which is opposite of the standard layout. I’ve driven this before in the M Coupe with the BMW CCA, and I really enjoyed it. The shorter configuration means more repetition on the corners, which is great for learning. If you recall, last time I had a very oversteer prone setup, making for a few too many off-track excursions. Prior to this event I ordered up some Swift springs in a 6kg/mm and 7kg/mm rates for front and rear respectively, therefore shifting more of the spring bias towards the front from the original 4/6 setup. This should reduce the oversteer and bring the car closer to neutral. You can read more about the work in this post. Here’s a video from the first session. It was a pretty cold morning, and the track was very green. The Lotuses (Loti?) were have some serious grip issues, as you can see they were just poking around. I had a decent time playing with the Boss 302 Mustang, who eventually caught up with me as my tires were overheating (I pumped them up pretty high due to the cold.)
The good news, the spring swap worked, the car was far closer to neutral. The bad news was that my alignment and corner balance is still way out of whack. The car really needed to be taken to a track alignment specialist rather than the local Firestone. That will have to wait, because on my second session I got hit with worse news. While headed down the back straight I lost all power and the dash lit up with a CEL. I tried to turn it off and re-crank, but nothing. It would turn over just fine, I had fuel, and the temp gauges were all normal, but no starting. Fortunately I had enough speed to coast up through Ricochet and into the grid area. I would have had enough momentum to carry me back to parking, but some guy with no situational awareness decided it was a good idea to just walk slowly in front of my coasting car. I had to hop out and push it the rest of the way, fortunately a helpful soul joined in and pushed it back to my parking spot. This video tells the story:
The sounds heard in the video weren’t audible to me at the time, as I had ear plugs in and a helmet on. When I pulled in to parking I assumed it might be a simple wiring issue, as the car was having no issues turning over. I removed the rear cubby floor to access the Apex PFC stand-alone ECU and J&S Safeguard, checking all the connections. I even put the J&S into monitor mode to see if it was getting false knocking signals, still wouldn’t run. I had my PFC Commander hand-held tuner, which I used to check all the sensors. Everything was reading normal, as was my fuel pressure gauge. So it wasn’t a fueling issue, wiring, or sensor. It didn’t throw a belt, so I assume it was getting enough air. So maybe spark somehow. I tried cranking again, keeping the throttle full open. It would fire, but was running extremely rough, like a cylinder was down, and would only run with WOT. That’s when I decided to pull the plugs. Not exactly an easy job on the Spyder, as the rear X-brace has to come out to pull the coils (coil on plug.) I eventually got the coils out with the help of a fellow driver’s tool box, then I had to get a plug socket. Fortunately the guys from Texas Track Works were a few spots over and gladly loaned me the tools. I asked to borrow a compression tester as well, just in case it was a head gasket or blown set of rings.
I didn’t get to the compression check, because the first plug I pulled (Cylinder #1) looked like this:
Yes, that’s a smashed electrode, and smashed porcelain with it. There are only a few ways that can happen and none are good. There’s no fixing this at a track, so with the help of a few other drivers I pushed the car back on the trailer and called it a day. Rather than drive back pissed off and tired, I retired to the hotel room and decided to leave in the morning. The next day I woke to a fogged in Cresson, they definitely wouldn’t be out on the track in this. I found out later that they postponed all the sessions until after lunch due to the fog. That made me feel a little better about missing out but only a little. On the drive back I decided to give Dave at DD Performance Research a call and see what he thought. Dave is an all around 2ZZ-GE genius, and the man who tuned this car to begin with. I asked to drop the car off at his shop down in Sealy, TX, as I really have no room in my garage to take on another engine rebuild.
Once I reached Dave’s shop, he brought out a Snap-on borescope and dropped it down into the #1 cylinder. We could clearly see a valve standing on end, separated from its stem. So all that turning over wasn’t helping matters, but the damage was clearly already done. The worry is just how much damage may have been done to the underside of the head (#1 combustion chamber) and to the cylinder wall. See the 2ZZ doesn’t use steel or iron liners, it has aluminum walls treated with Metal Matrix Reinforced (MMC) coating. This coating is great for keeping the engine light and against normal wear from the the rings, but very easy to damage from things like valves and spark plug parts banging around. The top of the piston is also done for. So I’m out at least a valve-train and piston at a minimum, possibly a complete short block and head. That’s a kick to the underbody considering I have maybe 3k miles on this shortblock and reconditioned head that I built not too long ago. I should have scrapped the OEM valve-train from the beginning, especially since I was running longer duration Piper stage II cams. The engine wasn’t over-reved, no money shifts, but it’s already an interference design in stock configuration. So it’s possible a slight valve float could have created a meeting of the piston and valve and that’s all she wrote.
On a more cheerful note, here’s a little video of the Spyder shooting some flames at the Boss Mustang that was playing around with me during the first session, so enjoy.
In my most recent post I covered the many headaches involving the brakes on my M Coupe, which was solved by replacing the Speed Bleeders with normal OEM style bleed screws. This upcoming weekend I plan to take my MR2 Spyder to the track, and as part of the track preparations, I always check the brakes (among a slew of other items.) Well, I remembered that I had also installed Speed Bleeders on my MR2, better pull them and take a look…
Yep, four more mangled bleeders. That makes 10 for 10 that were damaged. I know some of you are going to say I was just over-tightening them. If you were to read my other post, you’d see that I tested two brand new ones by only tightening them until the fluid flow stopped, yet they were still damaged, albeit not to this extent. I’m also tightening them to the same torque I’ve always used on any car I’ve done brakes on. I’m no metallurgist, but I’d guess the grade steel these are made of is too weak, or perhaps they machined too much away to accommodate the check valve assembly. It’s really a moot point, as I’ll never be using them again. Back to good old, plain OEM-style bleeders.
The good news is that the BMW and Toyota use the same size bleed screws, and I had ordered 4 extras when I was replacing the M Coupe’s.
My first track day with the MR2 Spyder was a bit of a revelation. The car was very quick, but very prone to oversteer as well. It didn’t like any amount of steering under braking, and had to be under power while turning. Don’t get me wrong, it was fun, but not exactly confidence building. My original setup was a soft and street friendly 4kg/mm front spring rate and 6kg/mm rear spring rate. Even with the adjustable Whiteline anti-sway bars set full stiff up front and full soft out back, it wasn’t enough to tame it. The car gripped exceedingly well at the front, the new square 225 NT01s were definitely helping that. I needed a bit more front spring bias. Several track enthusiasts on Spyderhat were having good luck running stiffer springs in the front, so I decided to give it a go. My BC coilovers will also take Swift brand springs, so I ordered a set of 6k and 7k springs.
Normally you would have to completely remove the coilovers from the car to swap springs, but I figured I could save some time (and money in alignment) by doing it on the car, keeping the strut to knuckle bolts locked down. The front was very easy, as I just disconnected the sway bar, and dropped the coilover from the tower. The top nut holding the camber plate and top perch on the shock shaft was busted with my impact gun. Then I just lifted the spring off through the large hole in the top of the shock tower. The new spring went on in reverse and everything was tightened down once more. The small bottle jack was used to lower and raise the lower control arm while I was working.
The rear was a bit more difficult, as the opening in the top of the strut tower is only large enough to allow the shock shaft and rebound adjuster to fit through, no way was I getting the spring in or out. So I dropped the spring perches as low as they would go and also screwed down the entire shock body as low as it would go. This gave me just barely enough clearance to finagle the spring out and over the shock rod. I also had to disconnect the trailing arms at the knuckle to allow the whole assembly to swing out far enough.
While I was under the car, I found a big surprise; the front right lower control arm bolt had nearly backed its way completely out. The nut was hanging on by a few threads. Had this come completely off it would have been disastrous while under way. I ran the bolt back in, then proceeded to put a socket/wrench to every suspension component. Fortunately this was the only loose one. To help guard from any future loosening hardware, I marked every fastener with torque striping to aid in quick pre-track checks.
I then had the dreadful task of setting ride height once everything was snug again. To do this job properly you really need hub stands and scales, as setting corner balance is really the benefit of having adjustable height coilovers. Unfortunately my garage isn’t that well equipped…. yet. So I did it the poor-man’s way (this is a poor man’s Boxster after all) and set the height with a simple tape measure to the top of the wheel arch. This isn’t the most ideal method, as the Spyder’s body panels are all bolt on, and not exact enough to get a true even setting. The other issue is that you are always going to have a little suspension bind when doing it this way. This is why your suspension “settles” after the first drive. It’s not really settling, it’s just that after dropping a car from a jack its suspension is in a state of bind until it’s driven. You can help avoid this by rolling it back and forth, but ultimately you need hub stands mounted on a plate that allows the suspension to slide. Either way, I did my best after several trial and error measurements and a quick drive to settle things out. Then it was off to the local Firestone to take advantage of my lifetime alignment (I don’t think they were expecting me to get alignments every other month.)
This past weekend was my first “real” track day with the MR2 Spyder. Following numerous mechanical issues, such as the coolant leaks, I finally had the car sorted enough to attempt a full track weekend. I had recently taken the car to TWS for an Open Track Day, which wasn’t that productive other than getting the brakes bedded in. It had revealed that the alignment was completely out of whack, which anyone could see just using their Mk-1 Eyeball. So I had it aligned locally to -3.0F and -2.5R camber, with zero toe on the front and just a smidgen of toe-in on the rear. The results were pretty dramatic, the car was now “driveable”. That said, it was still very prone to oversteer, especially under braking. I had to unlearn my trail-braking technique that was so critical with the M Coupe, and only brake in a straight line. Any amount of braking with steering input would result in a horrific tail swing.
Most of Saturday was spent just getting used to the car’s tendencies, and relearning the proper line. I’ve only driven the 3.1 configuration once before, and that was as a Green student in the M Coupe. I was now in the Yellow run group, and soloing most of the time. My instructor rode with me two sessions on Saturday, which was very helpful, other than the car being so damn loud that we couldn’t really hear each other on throttle. He rode again with me one session on Sunday, and I even took a ride with him in a rental Camaro SS. After the Spyder, the Camaro was like riding a Lazy Boy around the track. Of course it’s handling was more akin to the M Coupes, requiring trailbraking to set the front and get it to rotate.
Here’s a video of my final session on Sunday, where I set my best time of 2:35. That’s over 13 seconds faster than what I did in the M Coupe. I’m not sure that’s very impressive, given that I’m now on NT01 tires and have a much better power-to-weight ratio. Watch the entire video to see how the rear continues to get looser as the session goes on. The heat was really building in the rears more than the front.
All in all it was a very fun weekend and a great learning experience. I know I have a lot of things to work on, and the car needs a little help in the suspension setup department. I really need to increase the grip at the rear end. With the new square setup, the car easily (too easily much of time) rotates. The front end goes wherever the steering wheel points it, with absolutely no hint of understeer. That’s a huge difference when compared to the M Coupe. I also need to get a better feel for the shifter action. The gates are tighter, which can make mis-shifts easy. The engine also has to be spun up to really produce power, which necessitates more shifts and use of 2nd gear in slow corners. Hopefully I can get the car to another OTD or some other test n’ tune session to work on setup.
In this last photo you see the broken off tip of an exhaust valve from the #1 cylinder. It broke right at the retainer and looks as though it was a material failure. Lesson: probably shouldn’t rely on used OEM parts in an engine producing 310hp to the wheels out of 1.8L.
