After MOWOG 3, I had a few things to think about, and a few adjustments to make.
I installed the data logger setup, as well as the SpeedoDRD as mentioned in earlier posts, but I still had concerns about the cause of that spin in the back. The current thought was that I bottomed out that strut, and it threw the car.
In order to remedy that, I jacked the back end back up, and took about another half inch out of the overall length of the shocks. This time, I make sure to add the needed zip tie to measure just how much travel was actually being used. When I checked the zip tie on the other side it was all the way at the top. This is the side that has the extra inch of travel, so I doubted that it was bottoming out. I figured the ziptie was too loose, and had carried momentum from a quick hit past the point of shock travel. I reinstalled new ziptie that was tighter.
Overall length wise, this is about as much as I can take out of the rear shocks before I fully compress the tender springs. Further than that, and I may begin to adjust the static ride height by compressing the springs with the shocks which would demand a re-alignment.
All these tasks completed, the car went back on the ground and for a test drive. No significant changes to the handling.. maybe a little bit smoother. it would have to wait until the event to see if the desired results had been achieved.
Unfortunately, the mid week weather reports didn't hold out. A storm was definitely brewing. The Good news was that STU was running first.. but in the COM ways, they're breaking the heat into three sub groups. By where you stood. I made sure I was standing in the 1A group as I really wanted some dry runs to see if the issue in the back had been sorted out. Also, hey.. what autocrosser hasn't seen the "one dry run was the fast one" situation play out a few dozen times?
I landed in 1A, much to the chagrin of most of the other STU drivers who landed in B and C. Whatever, I'm not really fast enough to be a threat right now anyways.
Antsy as all hell, the car was running and ready to rock when they called for the first group. Right down to the starting line I drove. First car off.
I was a bit tentative, but still laid down a good time... if I hadn't hit two cones. I just can't get my damn head around how wide this car is.
Time for the second run, I'm gentler around that first cone I hit, but otherwise I've bumped up the intensity. it's starting to step out more. I make it to the top of the hill... and... damn. Spun again. Not a comfortable place to spin either, but I followed the rules. No wheels off, no cones hit, and didn't even DNF. At least I don't have to go home early.
As I pulled back into line the rain started. Shit. So much for useable data. And I began to think about my two spins so far. both times when loading up the right rear. In the conditions presented, I should have had enough grip for how fast I felt I was going, but the car just let go.
This last run of the morning, I tried a little more in the slalom. it definitely felt like any time that right rear loaded up, the car wanted to step out, where the left rear felt planted. I'm still not entirely sure if this is just me being hyper-aware of something that I think is a problem, or something that actually is a problem, but I'm going to look into it as a problem.
Upon returning to grid I checked my zip ties. there was about an inch of available travel left in the right rear, and almost 1.5-2 inches left in the left rear. I wasn't bottoming out the struts.
The rest of the day wasn't great. the rain continued for awhile, but letup for when I had to work. and then started again just in time to put me in the wet for all of my afternoon runs. I tried a little more to loose time, but my confidence in the car was shaken after that spin, so I kept finding myself pussyfooting on the gas and braking gently.
Up until the last heat, I had actually been standing in second on the power of my first run, despite the cones as everyone else had to deal with wet runs. But, fortune smiled on a few of them as it stopped raining quickly in 1A, and began drying for B and C where they were able to catch up.
So, now I'm playing through things in my head, trying to figure out what's wrong with my right rear. First one is that the toe bolt may have slipped. here's hoping that's a simple one. Next up is a ride height issue. When the car was at Jeff's I remember there being a height difference between the rear wheels. The margin escapes me and which direction, but we wrote it off as insignificant at the time. Now, I'm starting to think otherwise. And the car was not corner balanced in it's initial alignment.
The good news is that both of these issues can be fixed with another appointment to Jeff, with an order for a full corner weight and alignment. I'm also going to re-assess ride heights a little, and this time focus on keeping the factory height stagger of 3/4" higher in the rear before corner weighting.
I'm really hoping to slide into Jeff sometime this week for that work, but I'm pressed for time and so is he. and my error in over filling the gas tank makes getting a good corner balance a more difficult thing as I need to run it down before that.
If that doesn't rectify the issue, then it's on to bigger problems. That is the corner with the screwed up strut, so a replacement set of Koni somethings for the rear may have to be ordered.. otherwise it's also possible for it to be a shot bushing or ball joint providing too much play.
Fingers crossed it's something that can be fixed with adjustments though, because i'm feeling kinda tapped out at the moment.
Monday, June 23, 2014
Quick Mods: Data Logger
Knowing I'm going to be using my SoloStorm data logger setup a lot more than I have been, I opted to more permanently install a few aspects of the unit.
First up was the biggest, the tablet. Unfortunately, there isn't a tablet mount made specifically for the Hisense unit, so the universal ram mount I bought had to do. It works fine, but the tablet is a little looser in the holder than I'd like.
When I bought the tablet mount, I ordered it with a 2" screw mount base. When took the center stack out to install the Speedo DRD, I also drilled and mounted the base in the cubby hole.
With that installed, the arm and tablet holder just clamp down on that ball. It's a little tricky to tighten, but once it is it's pretty much ready to go.
Next up was the Bluetooth OBDII reader. I've got the PLX Kiwi unit, which used to be the one recommended by PetrelData before they started selling their current "high-speed" offering. It has a pretty quick refresh rate, but it has one downside.. it's got about a 3 ft cord. Why? I have no idea. Every other Bluetooth OBDII module on the planet seems to get away with building itself into the plug.. but nope, not PLX. Gotta be different.
Regardless, I plugged it in, and pulled off the kick panel next to the OBDII Port. Thankfully, there's a generous helping of room in there, so I wound up zip tying it to the wiring loom. Works fine, and still lets me easily plug in a different diagnostic tool should the need arise.
The last part of the data logger is the GPS nugget. A lot of people have mounted these on the dash with velcro, and that works well enough. But after some reading, and a little bit of messing around, I've found you've really got to get them outside for best and continuous line of sight. Otherwise, your accuracy falls and it's drift city. For this little guy, I found a suction cup mount specifically for GPS nuggets on amazon. A little bit of velcro and a zip tie for good measure, and we're off to the races.
First up was the biggest, the tablet. Unfortunately, there isn't a tablet mount made specifically for the Hisense unit, so the universal ram mount I bought had to do. It works fine, but the tablet is a little looser in the holder than I'd like.
When I bought the tablet mount, I ordered it with a 2" screw mount base. When took the center stack out to install the Speedo DRD, I also drilled and mounted the base in the cubby hole.
With that installed, the arm and tablet holder just clamp down on that ball. It's a little tricky to tighten, but once it is it's pretty much ready to go.
Next up was the Bluetooth OBDII reader. I've got the PLX Kiwi unit, which used to be the one recommended by PetrelData before they started selling their current "high-speed" offering. It has a pretty quick refresh rate, but it has one downside.. it's got about a 3 ft cord. Why? I have no idea. Every other Bluetooth OBDII module on the planet seems to get away with building itself into the plug.. but nope, not PLX. Gotta be different.
Regardless, I plugged it in, and pulled off the kick panel next to the OBDII Port. Thankfully, there's a generous helping of room in there, so I wound up zip tying it to the wiring loom. Works fine, and still lets me easily plug in a different diagnostic tool should the need arise.
The last part of the data logger is the GPS nugget. A lot of people have mounted these on the dash with velcro, and that works well enough. But after some reading, and a little bit of messing around, I've found you've really got to get them outside for best and continuous line of sight. Otherwise, your accuracy falls and it's drift city. For this little guy, I found a suction cup mount specifically for GPS nuggets on amazon. A little bit of velcro and a zip tie for good measure, and we're off to the races.
Sunday, June 15, 2014
Quick Mods - Speedometer Corrector
So, After driving the car for a little while with this wheel and tire package, the speedometer has finally driven me nuts.
I knew it would be off, but it's harder to deal with than I thought.
In comes a post I came across over on my350z.com: DIY: Speedometer corrector
The unit I ordered is the SpeedoDRD U1 by 12oclocklabs, the same unit the original poster used.
It's a simple little single board that's actually pretty powerful. It'll let you do +/- spedo percentage corrections all the way up to 100% (double), as well as convert MPH/KPH or vice versa, and even remembers your top speed for later recall.
But installation requires a bit of cutting and soldering. Thankfully, I stashed the entire FSM for an 08 350z in my Google Drive. It makes it accesible anywhere and easily searched. Finding the wiring diagrams and information was just a search away.
Before I started the whole process, I took note last time I drove the car of two different speed measurements, one from the GPS on my phone, and the other from the car's digital speed readout on the multi-gauge. Going 67MPH per the GPS, indicated I was doing 74MPH on the dashboard. Using the handy-dandy calculator 12oclocklabs provides on their website (here) that even tells you how to program the unit.
Digging thought the FSM I found how the gauge cluster works.
Under the stereo, what I thought was just the HVAC control unit actually drives the gauge cluster and triple gauge stack. In the case of the speedometer, it converts the CAN-BUS data being fed from the ABS system into a 0-5V signal that's fed to the gauge cluster, and then from there to the triple stack. It's this signal that we're going to intercept and modify. If you are going to try the same thing, but don't have the resources of an FSM.. the guys over at MightyCarMods did a similar modification with their own kit, and show how to find the signal wire with a multimeter: MCM Speedo Corrector
[caption id="attachment_152" align="aligncenter" width="225"]
The AC Module under the stereo. All the connections we need to make are on the middle connector.[/caption]
The white wire is the aforementioned signal wire, so we have to cut it in half.
[caption id="attachment_153" align="aligncenter" width="300"]
Snip the white wire, but make sure you give yourself enough distance to make repairs if necessary.[/caption]
With the signal wire split, we need to splice in the SpeedoDRD. The plug side is the source of the signal, and the lead goes up to the cluster. So we connect the white wire from the SpeedoDRD to the plug side of the white wire, and the blue wire which is the output from the DRD to the line that feeds the cluster.
[caption id="attachment_154" align="aligncenter" width="300"]
The signal wires connected.[/caption]
I used my soldering iron to do the job, and the provided heat shrink tubing. Next up, the unit needs power. The black wires on this connector are ground, and the Yellow/Green wire is an ignition power wire and will do the job just fine.
[caption id="attachment_151" align="aligncenter" width="300"]
Power and Ground Connections.[/caption]
A little electrical tape here and there, and it's good for a test.
A short while later, a test drive comparing to the speedo output of my tablet confirms the car's speedo is now dead-on accurate. Now I know if I'm not speeding enough!
I knew it would be off, but it's harder to deal with than I thought.
In comes a post I came across over on my350z.com: DIY: Speedometer corrector
The unit I ordered is the SpeedoDRD U1 by 12oclocklabs, the same unit the original poster used.
It's a simple little single board that's actually pretty powerful. It'll let you do +/- spedo percentage corrections all the way up to 100% (double), as well as convert MPH/KPH or vice versa, and even remembers your top speed for later recall.
But installation requires a bit of cutting and soldering. Thankfully, I stashed the entire FSM for an 08 350z in my Google Drive. It makes it accesible anywhere and easily searched. Finding the wiring diagrams and information was just a search away.
Before I started the whole process, I took note last time I drove the car of two different speed measurements, one from the GPS on my phone, and the other from the car's digital speed readout on the multi-gauge. Going 67MPH per the GPS, indicated I was doing 74MPH on the dashboard. Using the handy-dandy calculator 12oclocklabs provides on their website (here) that even tells you how to program the unit.
Digging thought the FSM I found how the gauge cluster works.
Under the stereo, what I thought was just the HVAC control unit actually drives the gauge cluster and triple gauge stack. In the case of the speedometer, it converts the CAN-BUS data being fed from the ABS system into a 0-5V signal that's fed to the gauge cluster, and then from there to the triple stack. It's this signal that we're going to intercept and modify. If you are going to try the same thing, but don't have the resources of an FSM.. the guys over at MightyCarMods did a similar modification with their own kit, and show how to find the signal wire with a multimeter: MCM Speedo Corrector
[caption id="attachment_152" align="aligncenter" width="225"]
The AC Module under the stereo. All the connections we need to make are on the middle connector.[/caption]The white wire is the aforementioned signal wire, so we have to cut it in half.
[caption id="attachment_153" align="aligncenter" width="300"]
Snip the white wire, but make sure you give yourself enough distance to make repairs if necessary.[/caption]With the signal wire split, we need to splice in the SpeedoDRD. The plug side is the source of the signal, and the lead goes up to the cluster. So we connect the white wire from the SpeedoDRD to the plug side of the white wire, and the blue wire which is the output from the DRD to the line that feeds the cluster.
[caption id="attachment_154" align="aligncenter" width="300"]
The signal wires connected.[/caption]I used my soldering iron to do the job, and the provided heat shrink tubing. Next up, the unit needs power. The black wires on this connector are ground, and the Yellow/Green wire is an ignition power wire and will do the job just fine.
[caption id="attachment_151" align="aligncenter" width="300"]
Power and Ground Connections.[/caption]A little electrical tape here and there, and it's good for a test.
A short while later, a test drive comparing to the speedo output of my tablet confirms the car's speedo is now dead-on accurate. Now I know if I'm not speeding enough!
Mission Report: The Maiden Voyage
After weeks of work, a little bit of shake down at a DCTC PDX, and plenty of street miles, it was time to finally turn the wheels in anger against a clock.
The venue for this initial outing would be DCTC, and the third event in our local MOWOG autocross series.
DCTC offers a unique challenge in an autocross event. Being a pseudo-mini-road course, if we ran it open it would be too fast to be considered an autocross. So we have to lay out elements on the road course to keep speeds down. Now, this would be a bit more interesting if we had the full 2-3 car widths of a legitimate road course, but DCTC being the aforementioned pseudo road course, most points on the track are only about 1.5 car widths wide. Definitely not big enough for an semblance of comfortable passing even on a straight.
So we make an already tight course tighter. And then I brought a wider car. Oops.
Right of the bat, i'll lay this out: many, many cones fell to the nose of the Z this weekend.
A combination of a tighter than average course and a car that was about a foot and a half wider than what i'm used to (probably closer to 3ft compared to last year) and you've got a recipe for the genocide of the cone race.
Now, on with the car. The handling was downright great. It transitions really well and turn-in is incredible. I'd thought these big ass wheels and tires would make the car feel really loagey, and while it does feel heavier than the WRX, it more than makes up for it.
But one flaw definitely made itself well known: the car needs a diff. Badly.
More than a few times I'd want to roll on the power for a nice smooth track out to only be met with wheel spin. Honestly it's easily the most frustrating part of the car at this point, the inability to use all those enslaved ponies under the hood in situations other than going straight or just the slightest bit of turning angle.
The differential has pretty much been highest on the list since springs, wheels, and tires were all obtained. In the process of building, I didn't wan the next upgrade to be shocks, as it would be so much casting pearls before swine. A diff will change the handling so dramatically, that it's really not worth the effort to chase settings in the mean time. I may play with bumping the front bar up a notch or two at a TnT event to see if it's worth making the car understeer more in favor of helping keep the rear wheels on the ground.
New this weekend was my co-driver Jake. Jake has some seat time in his crazy overpowered, under suspensioned evo, but we've been talking car stuff for a little while as he's been planning his own build of an 818 kit car, and you might say I have some history with Subaru stuff. Taking him for a ride in the 350 at the PDX event shakedown, his response was "mind blown" at how it could change direction, and expressed interest in a season co-drive, citing his need to get comfortable with a RWD platform before his own psychomobile comes to fruition. As a last minute thing, i floated him the offer to drive it, and he was onboard before i could even finish the chat message.
Jake really enjoyed himself, and was only about 2-3 seconds off my pace, but he has some bad AWD habits to unlearn, and some slip angle to reduce. That being said, I think you may see more of him in the front seat.
As to my own runs, i was initially a little disappointed. I'd coned all my fastest runs (okay, almost all of 'em. the other one I DNFed... but we'll get to that), but the times were landing me in the top 5 in STU and about 47th in PAX. I felt kinda despondent about the whole thing, thinking really hard i should be faster. It was when words of wisdom came down from our own local crazy car builder, Mark Yackich, did I really start to feel better. "you're on shitty shocks, with no diff, and an untested setup and you weren't DFL. I'd count today as a win."
Gotta hand it to him, he's got a point.
And finally, I finally got a good test of some of the analysis gadgets I picked up over the winter.
Right off the bat was SoloStorm software, but I've had that since mid last year. I did acquire a Hisense tablet specifically for it though, as well as a mount. It's using the same QStarz 10Hz GPS nugget (except i borrowed this one from Jody as i forgot mine on the charger), but i added the recommended PLX Kiwi for OBDII logging, and a GoPro Hero3+ Black for run video.
After mounting all this shit in the car it does yield some pretty good information, and i used it some to coach Jake, as well try to figure out where my errors are. In-car video isn't great right now, I'll have to mess with that a little more as i really want to see my steering inputs, but the light out the windshield is too bright and saturates the sensor. I'll have to see if I can set exposure manually to favor the outside light.
But when mounted outside, the final product does look awesome. Here's my last decent run, with the camera mounted externally.
In addition, here's the video from the first half of my last run. I say first half because... well.. just watch it.
Lastly, I have an additional point of view from that last run. I borrowed a pair of Google Glass from my office, and recorded from about an inch off my right eye. The effect is pretty cool
My theory is that I may have bottomed out the back right shock, and then unsettled the car when it couldn't travel any more. It's the one with less travel, remember? I don't want to pull any more droop travel out of the rear, but that may help. Sadly, I forgot to put the zip tie on that one to check travel, but there wasn't much left on the passenger side.
The venue for this initial outing would be DCTC, and the third event in our local MOWOG autocross series.
DCTC offers a unique challenge in an autocross event. Being a pseudo-mini-road course, if we ran it open it would be too fast to be considered an autocross. So we have to lay out elements on the road course to keep speeds down. Now, this would be a bit more interesting if we had the full 2-3 car widths of a legitimate road course, but DCTC being the aforementioned pseudo road course, most points on the track are only about 1.5 car widths wide. Definitely not big enough for an semblance of comfortable passing even on a straight.
So we make an already tight course tighter. And then I brought a wider car. Oops.
Right of the bat, i'll lay this out: many, many cones fell to the nose of the Z this weekend.
A combination of a tighter than average course and a car that was about a foot and a half wider than what i'm used to (probably closer to 3ft compared to last year) and you've got a recipe for the genocide of the cone race.
Now, on with the car. The handling was downright great. It transitions really well and turn-in is incredible. I'd thought these big ass wheels and tires would make the car feel really loagey, and while it does feel heavier than the WRX, it more than makes up for it.
But one flaw definitely made itself well known: the car needs a diff. Badly.
More than a few times I'd want to roll on the power for a nice smooth track out to only be met with wheel spin. Honestly it's easily the most frustrating part of the car at this point, the inability to use all those enslaved ponies under the hood in situations other than going straight or just the slightest bit of turning angle.
The differential has pretty much been highest on the list since springs, wheels, and tires were all obtained. In the process of building, I didn't wan the next upgrade to be shocks, as it would be so much casting pearls before swine. A diff will change the handling so dramatically, that it's really not worth the effort to chase settings in the mean time. I may play with bumping the front bar up a notch or two at a TnT event to see if it's worth making the car understeer more in favor of helping keep the rear wheels on the ground.
New this weekend was my co-driver Jake. Jake has some seat time in his crazy overpowered, under suspensioned evo, but we've been talking car stuff for a little while as he's been planning his own build of an 818 kit car, and you might say I have some history with Subaru stuff. Taking him for a ride in the 350 at the PDX event shakedown, his response was "mind blown" at how it could change direction, and expressed interest in a season co-drive, citing his need to get comfortable with a RWD platform before his own psychomobile comes to fruition. As a last minute thing, i floated him the offer to drive it, and he was onboard before i could even finish the chat message.
Jake really enjoyed himself, and was only about 2-3 seconds off my pace, but he has some bad AWD habits to unlearn, and some slip angle to reduce. That being said, I think you may see more of him in the front seat.
As to my own runs, i was initially a little disappointed. I'd coned all my fastest runs (okay, almost all of 'em. the other one I DNFed... but we'll get to that), but the times were landing me in the top 5 in STU and about 47th in PAX. I felt kinda despondent about the whole thing, thinking really hard i should be faster. It was when words of wisdom came down from our own local crazy car builder, Mark Yackich, did I really start to feel better. "you're on shitty shocks, with no diff, and an untested setup and you weren't DFL. I'd count today as a win."
Gotta hand it to him, he's got a point.
And finally, I finally got a good test of some of the analysis gadgets I picked up over the winter.
Right off the bat was SoloStorm software, but I've had that since mid last year. I did acquire a Hisense tablet specifically for it though, as well as a mount. It's using the same QStarz 10Hz GPS nugget (except i borrowed this one from Jody as i forgot mine on the charger), but i added the recommended PLX Kiwi for OBDII logging, and a GoPro Hero3+ Black for run video.
After mounting all this shit in the car it does yield some pretty good information, and i used it some to coach Jake, as well try to figure out where my errors are. In-car video isn't great right now, I'll have to mess with that a little more as i really want to see my steering inputs, but the light out the windshield is too bright and saturates the sensor. I'll have to see if I can set exposure manually to favor the outside light.
But when mounted outside, the final product does look awesome. Here's my last decent run, with the camera mounted externally.
In addition, here's the video from the first half of my last run. I say first half because... well.. just watch it.
Lastly, I have an additional point of view from that last run. I borrowed a pair of Google Glass from my office, and recorded from about an inch off my right eye. The effect is pretty cool
My theory is that I may have bottomed out the back right shock, and then unsettled the car when it couldn't travel any more. It's the one with less travel, remember? I don't want to pull any more droop travel out of the rear, but that may help. Sadly, I forgot to put the zip tie on that one to check travel, but there wasn't much left on the passenger side.
Subscribe to:
Posts (Atom)