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Thank you!
I now have a target/clue/idea!!
Now, i go out to the garage.
Did you measure your spring compression from start to final? just curious how close they are?
Without having all the tools, and after using some made up scale and nothing was going right, I decided for now I will just set the Spring height as the same as I can and then measured after surprisingly there were not far off or at least go place to start.
That's one thing I didn't measure before I started. I had set my ride height on the front square tube to 4.5" and the rear to 4.75" (at least the best I could estimate without using Shanes method of the laser left on the flat patch) as my starting point.Originally Posted by KGTM
You are correct, without having all the tools to be able to accurately check weights and your alignment along the way, you are doing yourself a bit of a disservice even trying. you can see how little some of the changes I made impacted the overall corner weights throughout the whole process. It was definitely an investment to get a corner scale kit, bubble caster gauge (plus a custom machined bung to install on the wheel), digital camber gauge, string alignment kit, and turn plates. All told I think I spent close to $2,400-$2,500 just in these tools alone. And that's not counting the classes i took to learn how to even go about doing this. But, I wanted to learn this from scratch and do it all by myself because half this stuff a shop won't do for you, like set corner weights or alignment with the drive int the vehicle. Now, I can do all this in my garage.
I can say now that I got through this round of corner scaling, I went for a drive, zeroed the load on the sway bar, drove again, and then checked all the camber points and will now go back and readjust the alignment. Probably bring the overall ride height up a bit as the front left is a bit low. I'll share all these numbers and the delta from my base alignment in a couple days or so. I've got an early flight tomorrow for a week long business trip out west and need to hit the rack.
Wish I had you tools though. Here I even have hard time to get alignment. Using the spring with calipers and get as many as the coils you can grab in one measure did not word that bad.
Shoeless liked this post
Again, just for clarification as I did not see it mentioned, you must roll the car back and forth and jump on both ends of the car to set the suspension in between making adjustments and taking another scale reading. This is VERY important and will change the scale readings significantly. Without doing this your numbers will not be correct and there will be virtually no repeatability to you readings. You should have flat platforms either before or after your scales. Roll the car back and forth and bounce on the car only when it is on the platforms in order to not potentially damage the scales. All scales must be on a, relative to each other, level surface.
beeman liked this post
Yup, that was the hardest part moving the car on and off the scales. hence I gave up after hours using scales. I think you will need the Shoeless scale system.
Shoeless, if possible will be nice to see how the spring hight matches.
Crash is absolutely right about needing to settle the suspension after each change. In addition to rolling back and fourth and jumping on the corners, there is another way, slip plates, or something that functions as slip plates.
When I set up my flat patch with the floor tiles I noticed they slipped pretty easily on one another and found out if I use two of these tiles on the top side of scale as slip plates, I can raise and lower the car right on the scales then settle the corners by bouncing on each corner. Very repeatable and I don’t have to worry about rolling on and off with the ramps, which works once you get used to it.
Here's a refresher of where my original alignment was set at.
FL:
Caster: 7.33 deg
Camber: -0.3 deg
Toe: -1/8
RL:
Camber: -0.3 deg
Toe: -1/16
FR:
Caster: 7.25 deg
Camber: -0.5 deg
Toe: -1/8
RR:
Camber: -0.5 deg
Toe: -1/16
After the corner weighting process I went for a drive and then I checked the camber as an easy check for what has changed and here is where that is at.
Here are my initial impressions after corner weighting:
- Straight line acceleration was more behaved, didn't have to over steer
- Steering wheel is off center to the right
- Alignment is off
- Very responsive left and right, but due to misalignment snappier to the right.
- Cleared the driveway and speed humps easily without need the Stance Air Cups engaged
No Driver:
FL Camber: -0.3 deg
RL Camber: -0.1 deg
FR Camber: -1.1 deg
RR Camber: -0.8 deg
With Driver:
FL Camber: -0.4 deg
RL Camber: -0.2 deg
FR Camber: -1.2 deg
RR Camber: -1.0 deg
From here I'll likely raise the whole ride high by one turn per corner, recheck corner weights and ride height and then get into redoing the alignment.
After much back and fourth looking for an optimum setup, here is where I finally landed today.
Alignment with driver:
Front Left Camber: -0.5
Front Right Camber: -0.5
Front Left Toe: -1/16
Front Right Toe: -1/16
Rear Left Camber: -0.6
Rear Right Camber: -0.5
Rear Left Toe Left: -1/32
Rear Right Toe: -1/32
Ride Height with driver:
Left Front: 4 7/16”
Left Rear: 4 25/32”
Right Front: 4 9/16”
Right Rear: 4 3/4”
Ride Height with out driver:
Left Front: 4 21/32”
Left Rear: 4 31/32”
Right Front: 4 11/16”
Right Rear: 4 13/16”
Corner Weight with Driver:
Left Front: 521 lb
Left Rear: 731 lb
Right Front: 352 lb
Right Rear: 783 lb
Left: 52.49%
Cross: 45.35%
Rear: 63.41%
Total Weight: 2386 lb
I was able to go for a quick test drive before some rain moved in and I was very pleased with how straight it tracks, snap turns left and right feel equal, and straight line acceleration was very well behaved.
How much caster?
Whoops, left that out. Very well behaved coming out of turns.
Front Left Castor: 7.33
Front Right Castor: 7.25
Hey fellas,
Over Christmas break I was getting pretty stoked to finish off the majority of the work I planned on doing on the GTM before sending off for body work and interior and stumbled upon yet again another issue with my AEM Infinity ECU. I decided to start and play with some of the additional features within the ECU, Traction Control and Launch Control. These two features were at the top or near the top of reasons why I went with an aftermarket ECU to begin with.
I started with Launch Control first. The AEM is pretty straight forward, check off a few boxes, set RPM limits for fuel and spark cut and you are all set. I decided to check the functionality of each the spark and fuel cut just to see how the engine behaved. I turned off spark cut, turned on fuel cut, set the RPM to 1500 and floored it. Sure enough, RPMs went to my set point and then held there. Sweet, now let's try spark cut. Hmmmmm spark cut isn't working. I tried adjusting several parameters and still nothing. So I threw a FB post up in an AEM page and within an hour I had a guy remote into my computer to check everything. Still didn't work. So we tried to trick the system by changing the parameters for the 3 Step and still nothing. The guy I was working with said the next dreaded few words. You have a problem with your ECU.
Here I find myself, once again with an AEM ECU issue. I'm done. I spoke to Joel at RaceSpec early last year when I had the throttle body issue about converting to a full MoTeC setup up. At the time AEM finally replaced my unit and it functioned properly, plus the learning curve and cost to go full MoTeC is huge. So I shelved the idea at the time. Now, I'm fully committed to a full conversion. I'll get AEM to address this unit, but once fixed, it and every AEM item (ECU, CD-7 Race Dash, Vehicle Dynamics Module, CAN Expansion Module,...everything, probably even the 12 position switches I have on my steering wheel button plate which means I'll likely create a new one) in my GTM will get pulled and sold.
I spent a good bit of time over Christmas break reaching back out to Joel and investigating what all needs to take place for this conversion. The largest hurdle is lead time and availability issues. MoTeC just like every other manufacture that requires chips is having issues. There are no lead times being posted and you basically put a deposit down and wait. The first item to look at is the ECU. Joel recommended an M130 or M170 as he did one of these in a GTM a while back and it worked perfectly. The M170 is essentially the same as an M130 except it uses a single high density Deutsch AS connector versus 2 Amp Superseal plugs. With that difference comes a noticeable jump in price, but I was open to it if we could find one. Sure enough Joel located an M170 and should have it by the end of March. Not terrible, especially when he told me he is still waiting on M130 order to be filled from March of 2022 (Holy crap!!!). From here we looked at what other hardware I was interested in. Next up was a dash. MoTeC has a 5", 7", or 12" dash and a couple different levels of functionality. I landed on a M127 (7") with the Amp Superseal plug for the moment as the price jump to a M187 (7" with Deutsch AS plug) is HUGE, plus I don't need all the functionality. I'll also need a Lambda to CAN, as well as new wideband O2 sensors, and a new 6 axis dynamics module.
Next up I needed to create some documentation on how I was to convert my harness to now plug into an M170, the part I feared the most. After a lot of deliberation and a lot of sleepless nights, I have a general plan. I literally went pin by pin from AEM to MoTeC for every input and output and then what needed to change in my power distribution block. With 9 new splices, I can make every input/output work and then needed to look at power. Of course the power demands of the MoTeC are drastically different than the AEM and I will need to change the trigger type from a low side signal from the AEM to turn on all the relays, to a high side signal from my switched ignition to do the same function. All while sending the proper switched power to the MoTeC. I listed all the needed changes and so far, it's not impossible. Not fun, but not impossible.
I've been watching all the HPA videos to familiarize myself with the MoTeC M1 software and sent off my configuration sheet to Joel for him to charge a few hours of consultation time to make sure I'm headed down the right path.
Overall, not what I wanted to be spending my time and money on at this time, but I'm optimistic that once complete, this will be for the best.
VRaptor SpeedWorks, LLC liked this post
Dang....sorry to hear about all of the headaches you're running up against here. Sounds like you have a good handle on it.....good luck!
Shane Vacek
VRaptor SpeedWorks, LLC
www.vraptorspeedworks.com
Turn-key GTM, SL-C & Ultima GTR Built to Your Specs!
Offering a full line of GTM Upgrades and Custom Parts
Shoeless liked this post
Yeah, no fun at all.
If you continue to have issues, I do know a Motec dealer here in CA that seems to stock a lot of stuff. Sounds like you are pretty invested with your Motec contact so stick with him, but if you need hardware and are not able to locate it, let me know.
Shoeless thanked for this post
Yea, this plan took many many hours to throw together and many sleepless nights before I realized it would be 100% possible. Once I nailed that down, I was pretty happy. Documentation will be key to this, just like my original harness.
Hey crash, thanks for the offer. Yea I'm pretty tied into Joel at RaceSpec, but will reach out if I need to. Thank you!!
Sorry to hear this, I know you have a ton of time in this system and harness already..
MK3.1 2004 Mach 1 donor. ABS, PS, TC.
GTM #304 LPE 525hp LS3
2000 C5 Lingenfelter LS1@489hp
1999 Corvette FRC/Z06 track car
Shoeless liked this post
Well shoot, this once again becomes a realization of the worry I've had about the Infinity since I plan to make use of all of the features they offered with their ECU. I guess I'll just need to cross my fingers until I get to that point and have the Motec in the back of my mind as a possibility. Really sorry to hear of the extra trouble and soon to be extra expenses!
Having said that all, I have the smaller CD5 and no VDM so I'd be up for a possible CD7+VDM purchase if you don't sell everything as a bundle.
Gen 3 Type 65 Coupe builder
Thanks beeman, yea now that I'm over the hump of making the call to do the change and gone through all the inputs/outputs from AEM to MoTeC, I'm feeling better about the decision. My bank account on the other hand, really doesn't like my decision LOL.
Yea, that feeling that one day something won't work has haunted me since my DBW TB issue early last year.
Until I locate a MoTeC C127 Dash, I may need to hold onto the CD-7 just to confirm engine function when I get the harness converted and the M170 incorporated, but I will gladly pull the VDM and sell that right now. I'll shoot you a PM.
I read a while back on a review of the aftermarket ecu's that the author said aem's customer support is excellent... He then followed up with "which is great because you're going to be using them alot". Sorry to hear about your problems. have you ever heard of anyone running Holley terminator or megasquirt? I haven't seen much in the forums about either one.
Yea, that sounds spot on with AEM, especially on the ECU I have. Interestingly enough, AEM was just sold to Holley. Word on the street, and has been confirmed by what I see, AEM will no longer service any of their ECUs if they are outside of the 1 year warranty window. That leaves the issue of who can actually perform repairs on their units. There is at least one company I saw that is trying to establish themselves as a repair facility, but they are just now digging into what actual repairs they can do. Its not like a separate standalone company can just stand up and say we can repair their units. They have to figure out what they can and cannot repair.
The shop (Gearhead Fabrications, Jensen Beach FL) that did the final tuning on my GTM really likes Holley Terminator. They install that on nearly every one of their builds, which is a lot. They have a pretty good following after establishing themselves. Hell, they did a GTM about 6 months before mine and they did a bang up job on mine and was very pleased with the tune.
I have heard of Megasquirt, but from my experience I put these in the same group as Holley and/or even AEM. My assessment could be off, but they are more along the lines of a "hobby" setup. Can it be setup to run a car and have a few extras, sure, but that's about it. Will it work for some people, sure, but do you want a lot more functionality with the ability to do damn near anything? You will likely feel disappointed with them.
For me and my engineering background, I want to know everything and be a part of every aspect of the technical parts of my build. For example, can a shop set up launch control and traction control strategies on your ECU, maybe, if they would even offer that service. In my mind this is really up to the driver to take out and test in all the conditions that are appropriate and set up these strategies. No shop will be able to set this up in all real world conditions with a huge expense. If I knew then what I know now, I would have gone full MoTeC to begin with and be done with it.
I did hear from AEM yesterday on my issue. As is typical they asked for a data log of the issue, so I sent that to them and am waiting for their response.
I checked into the Holley a while back. I even called them and talked to the tech department. They are really popular with drag racers. The main issue I had with them is the tech said the traction control was designed to work off the line from a dead standstill. He said it was not designed to work say coming out of a turn, for that I would need to look somewhere else. just fyi.
Shoeless thanked for this post
So that would be launch control not traction control.
This is exactly as I see it as well.
Just so you get a feel of what I do with the FFR PDG GTM, I run all new or rebuilt engines on an engine dyno for initial tune. Then the engine goes into the chassis and a chassis dyno session is run. Then the car is put on the track and I either have the tuner at the track to adjust things right there, or we send data so he can do that remotely. Our ECU, which is not Motec, but a same level type unit, can be seen via internet and the tuner can remotely change the ECU from his shop no matter where we are in the world. One of the best features of this type of ECU, as I see it, is the preciseness that can be achieved. We do individual cylinder adjustments on the dyno, and then the system safeties, such as knock retard, can make changes to individual cylinders as well. All of it is precisely data logged and we can analyze and adjust later. These are much more powerful ECUs than the "hobbiest" models, but you do pay for this technology and support.
Thanks for the insight on what the FFR PDG GTM team does. Its really cool some of this functionality. Especially when you get into individual cylinder type tuning. I'd venture that most people don't even realize the benefit of this type of tuning, let alone have the sensors and hardware to even do it. It gets expensive pretty quickly
The point being made here is you can do a hell of a lot of things with higher end, race inspired, and tried and true tested hardware. I will likely be adding a very similar wifi controller to my build to allow myself or a tuner to access both my M170 and the C127 simultaneously from outside the car.
For me, this was an expensive lesson in learning what a hobby ECU can do, compared to a higher end unit. Same thing with support. If those that followed along remember, my DBW TB issue was only solved when a guy on Facebook contacted me when I posted my issue saying he had a engineer friend at AEM and he would contact him directly to help me out. Sure enough it took me sending my ECU to AEM TWICE for them to finally accept the hardware was bad and they owed me a replacement. Simply by the kindness of a stranger I was able to get it addressed. If I didn't have that, I would have had to buy another ECU. After this was all solved, I paid for a dinner out for this guy and his wife as a small token of my thanks.
Replace the same corner spindle with a new one. (age old post response, I know)
Last edited by RR46; 01-17-2023 at 06:46 AM.
Restored GTM #82 w help of friends. Now cruising, tracking, upgrading.
I'm working on putting together a list of items I need to knock out as I'm waiting for the MoTeC hardware and needed supplies to show up.
One thing that came to mind was setting the temperature on my trans cooler pump. I think crash mentioned what temp they have their GTM set to, but I can't find that in my notes.
@crash,
What temp do you have your trans cooler pump turn on set at?
I run the trans cooler 100% of the time. I have just put in place a transaxle to engine coolant heat exchanger so the trans runs at the same temp as the engine coolant. Not only does this keep the transaxle in the correct temp range, but it heats up to working temp faster and the heat exchanger takes up much less space than a regular radiator cooler and fan. The exchanger also eliminates the fan electric load.
I would suggest a fan cut in temp of around 210-220. Transaxle shouldn't run higher than 250-275. The oil will likely be okay, but the ring and pinion will excessively wear above those temps.
Excellent, thank for the help!!
I've been pretty busy creating documentation and getting items on order for the MoTeC swap, but decided to spend some time in the garage this weekend. I ran all the wiring for a front camera that will feed into the C127 triggered by one of my steering wheel buttons, then went on to calibrate the trans cooler pump turn one. I've got a Hayden Universal Adjustable switch that I installed long ago when I was doing the wiring up front, but never set it.
The setup was pretty simple, get a hot plate and bring some water to 210-220, then set the dial on the switch for the relay to kick on. Unfortunately, it just didn't work as planned. After bringing the water to temp and checking with my instant read grilling thermometer and adjusting the dial, nada. I jump into troubleshooting mode. I'm getting power to the switch, check. I jumped the power to bypass the relay, and I get 13V at the rear, check. I pull the relay and trigger it myself, yup the relay is good, check. I cut the wires to the temp sensor and measure the resistance and its around 5K ohms while the water is around 205, then checked it again while cooler and yup the resistance is changing as expected. I grab my box of resistors and try really high and really low ohms connected to the switch, adjusting the dial and nothing. So either I have failed to hook this thing up correctly, or I've got a bad switch. Time to go find the instructions and see what I’m missing.
Last edited by Shoeless; 03-12-2023 at 08:14 PM.
Sometimes it the easiest things LOL. I discovered by starting back at the basics after reading the instructions again, power, ground, and switched ignition trigger, I discovered I removed the switched ignition trigger. I must have done this when I first installed this as a prevention to mistakenly activate this switch. Hooked it back up and boom, all works as planned. I was able to set the turn on around 212-214 and it appears theirs is a 5-8 deg hysteresis built in. For anyone using this same switch I ended up about 1/16 of a turn from the max setting.
Just a point of clarification here. I would recommend the trans temp running at 210-220. This is where I would run THE FAN. For us, the pump does circulate fluid to the cooler, but also serves the important function of moving lube to the critical areas of the gear stack as well. You may want to consider running THE PUMP full time, and only having the fan on the thermostatic switch.
Shoeless liked this post
Hey guys,
Over the last several months, I've chased a VERY small coolant leak somewhere in the area of the thermostat area of my water pump. I would wipe up the single drop or two of coolant, tighten the t-stat housing, just for it too reappear. Thought maybe the hose clamps just weren't tight enough, nope that wasn't it. FINALLY I was under the car a number of weeks ago and just happen to look up and see wetting around the heater outlets. As a refresher I pulled the fittings out, tapped these holes, and put in pipe threaded 45 deg angle fittings. I saw this done long ago before I knew better and thought hmmmm seems like a great idea, yea not so much now. One of the fittings was leaking just ever so slightly. Instead of screwing around with them any more, i just replaced the water pump.
Since I had the cooling system tore apart, I borrowed the idea from another forum member of powder coating the coolant expansion tank. It will be MUCH easier to keep clean than polishing aluminum half way into the engine bay. Now everything really matched. I also needed to make a new bracket to hold the MoTeC Dual NKT LTC module, so I integrated this with my transaxle catch can.
My good friend's daughter is really taking a liking to becoming a mechanic instead of going to college so I invited them over for her to help me put it all back together. It was awesome to share the basics of my GTM setup, and engine mechanics in general to her as she put it all back together under my direction. It was a great morning inspiring the next generation who takes an interest in this type of work. She was grinning ear to ear the whole time. Once the coolant system was topped off, I let her start it and keep an eye on the coolant levels. I still need to get a little air out of the system, but that's more grunt repetitive work to get it set right. Once that's set its time to make a running and driving GTM a non running GTM by pulling the engine harness for its MoTeC plug conversion. I totally forgot to take some pics of her working, but I'm sure her dad snapped a pic or two.
What a great time!!!
As I was pulling my engine harness, I noticed a crack in the cap I had on the passenger side valve cover breather port.
Anyone have a link to a nice 90 deg small filter I can throw on here instead of capping off?
Interestingly enough when I swapped over to the NTK O2s I had to pull part of my PCV bypass apart and figured I'd check the catch can. There was about 3/4" of oil in it. Not sure if from more of my time driving the car before a proper tune or recent. Either way, will be part of my regular service to stay on top of it.
Use a urethane cap...or...pull the breather tube out and put a pipe plug into the hole. The blue anodized aluminum ones from Summit look pretty good.
Also, we get some oil in our breather system on the FFR PDG GTM race car and I have redesigned the system so that the build up returns to the dry sump tank. I would recommend that you do the same so that it drains back down into the oil pan and then it will be "self draining".
Last edited by crash; 05-31-2023 at 10:05 AM.
Thanks for the pointers, always on point.
I'll have to think through a return type system and see if I can get that done.
Saw your other post, what is the plan for the car in Iowa?
MK3.1 2004 Mach 1 donor. ABS, PS, TC.
GTM #304 LPE 525hp LS3
2000 C5 Lingenfelter LS1@489hp
1999 Corvette FRC/Z06 track car
I'll be having Shane finish my interior and body work. Unfortunately, my lower back is giving me more issues and don't see me being able to physically finish this. I originally had L5/S1 fused in 2007 from an injury in Iraq, fused L5/L4 last year with two surgeries, and already injured L3 by simply bending over to pick up my shotgun one morning. My surgeon says he can't keep operating on me and this one will be major if we have to go down that path. He's finally telling me to cut out fishing and anything physical. Completely sucks, but I want to salvage my back enough to be able to at least get in and out of the GTM and enjoy driving it.
VRaptor SpeedWorks, LLC liked this post
Man, so sorry to hear that. I know how much you enjoy those activities. Hopefully the back issues improve on their own over time. Please keep us updated as you get updates from Shane. Any exterior mods or add-ons, or stock FFR?
MK3.1 2004 Mach 1 donor. ABS, PS, TC.
GTM #304 LPE 525hp LS3
2000 C5 Lingenfelter LS1@489hp
1999 Corvette FRC/Z06 track car
Shoeless liked this post
Yea it's rather unfortunate I only got 6 good months after the last surgeries before injuring myself again. When I was originally injured in Iraq I had a tear in my L5-S1 disc, with the two above it injured but not bad enough for surgery and 3 discs in my neck in the same situation. Hopefully it will get a bit better over time.
I'll definitely keep everyone posted as I get updates from Shane.
I'll be going with several items that Shane offers and asking him to so some one off items. From his complement of louvers, to a custom interior, to his fiberglass and carbon fiber rear hatch piece with the two functional scoops. I'll also be going with a two tone paint job with Aston Martin Apple Tree Green with Gloss Black down the center hood, roof, and portions of the back hatch.
I know I'm putting it in capable hands and can't wait to see the finished product!!!!
Yeah....that really sucks on your back. Very sorry to hear that you continue to have issues and pain. Not fun stuff. I got really lucky on my back and avoided surgery and was fortunate that some anti-inflammatories and time got me back to "normal".
Looking forward to getting started on your GTM......hopefully I can match the quality you've already put into this thing!
Shane Vacek
VRaptor SpeedWorks, LLC
www.vraptorspeedworks.com
Turn-key GTM, SL-C & Ultima GTR Built to Your Specs!
Offering a full line of GTM Upgrades and Custom Parts
Shoeless liked this post
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