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Thread: GTM roll cage modifications and race car build log

  1. #721
    Member kabacj's Avatar
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    Quote Originally Posted by mikespms View Post
    Hey John,

    Here is my 2 cents,I used the corvette abs and don't have a bias problem but in the process of researching the compatibility of the master cyls with the ebcm and adjustment of the balance bar I spent some time on the phone with wilwood tech service....That been said you could use a 3/4" and 5/8" master to adjust you bias but it was not recommended with the corvette brakes. As far as bias on the pedals assy it is done with the balance bar and it is what it is,you need to make sure that you have free play on your master cyl rods or your will be dragging you brakes.An adjustable valve is an option. On the clutch side you need to cut the rod or you will bend it, I change form the FF supplied 3/4" master to a 5/8" master for a better pedal feel and slave operation.

    Mike

    On the brake caliper vs piston setup.

    Stoptech custom sized the pistons in the calipers they sent to match the willwood master cylinders and pedal assembly that comes with the kit. I must say I am happy with it and the balance bar is all I need in order to adjust bias. I am sure you cant get to the same place by adjusting the master cylinders to the calipers you ended up using.



    Thanks for the info on the clutch MC. I knew I remembered cutting something




    Quote Originally Posted by crash View Post
    Also note that pad material will make a HUGE difference, so if you are having an issue where the rears are locking up first and the pad material is different front to rear, the first thing I would do is make sure and change to the same material at both ends. This can have a dramatic effect on how the brakes operate.
    Crash,

    I ended up using the performance friction PFC 7793.01.18.44 in the fronts with matching compound rears. I like the bite and ability to modulate as well as the fact they last forever. Normally you get good wear or good bite, but I think the light car and 14 inch rotors helps get both.
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  2. #722
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    John-

    The PFC pads are something I have really encouraged our team (PDG) to try. According to my source at PFC they should have reasonable bite characteristics, and also last about 30% longer than any of the other manufacturers pads. Unfortunately, because of costs and the fact that we have a ton of stock on the shelf of other manufacturers pads, we haven't tried the PFCs yet. The other thinking is that we know how to use what we have, and the only time we have to change pads during a race is at the 25 hour event, where we change them at about 12 hours, so 30% better wear doesn't translate into not having to change the pads so we simply haven't spent the money to try the PFCs. Good to hear from you that they are performing as PFC advertises though.
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  3. #723
    Senior Member johngeorge's Avatar
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    Have you guys looked at the Pagid yellow enduro pad? We used them on ed's 25hr car and based on the wear we were getting we didn't have to change pads in the race. The calipers we were using allowed us to use a pad that was .8in thick, massive pads...
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    John,
    Thanks for your feedback on trailbraking, I am looking into a few things. Your new wheels look great. What size tires and wheels are you running this year? Will you use a different compound on the front and rear again?
    thanks

  5. #725
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    Quote Originally Posted by flickery8 View Post
    John,
    Thanks for your feedback on trailbraking, I am looking into a few things. Your new wheels look great. What size tires and wheels are you running this year? Will you use a different compound on the front and rear again?
    thanks
    The wheels are OZ racing 18x10 and rear are 18x12 with 2011 zo6 offset. They fit well and allow me to run 345s in the rear and 285, 295 or 315 up front. So far I have tried 245 on the stock GTM rims as well as 275 and 285 on the 10 inch wide OZ rims. When I am satisfied with the front tires I will adjust the body to cover the tires.

    I have four sets of front tires to test in the next few days I'll let you know what I find out.

    So far this spring I am running 285 Hoosier A7 up front and Hoosier 245 R7 out back.

    The A7 is the autocross compound so it heats up more quickly. Next week I will be at New Jersey Motorsports park for two days testing then heading down on Thursday to VIR again for the NASA Hyperfest. Since the chances of warmer weather are good I am bringing along a set of 295 R7 fronts. Just in case the autocross compound can't take a warmer track temp.

    The GTM is really easy on front tires. That's why I trail brake to keep them hot.

    A shot with a better look at the wheels.




    John
    Last edited by kabacj; 04-22-2015 at 05:16 AM.
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    Quote Originally Posted by johngeorge View Post
    Have you guys looked at the Pagid yellow enduro pad? We used them on ed's 25hr car and based on the wear we were getting we didn't have to change pads in the race. The calipers we were using allowed us to use a pad that was .8in thick, massive pads...
    We did look at the pagid yellows. At the time, three years ago, the company was going through a transition of ownership or something and the pads were not available for our calipers. The other problem is that because we are using all the "stock" FFR suspension, which equals stock Vette suspension, we are not able to fit the calipers that allow really thick rotors and pads. I have a nice set of Alcon calipers that use a 1.25" thick rotor and the pads can be 28mm thick, but there is no way to make these work with a stock Vette upright because the distance between the rim and the rotor simply can not be made large enough, so we are restricted to 18mm thick pads.
    Last edited by crash; 04-22-2015 at 07:56 AM.
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    After all this discussion about brakes and brake balance and how much the rods that drive the master cylinder contribute to the brake balance as well as how much adjustment one can get with the balance bar it was clear to me we needed some data.

    I especially wanted to measure the range of my setup. I wanted to be able to take it all apart put it back together and exactly duplicate the adjustments then verify them. I did some research. Turns out there is equipment for just such a purpose.

    I got this nice setup. It has the adapter for my calipers and quite a few others.




    I quickly instaled the gauge. I had a helper note down the pressure while I repeatedly tried to simulate max braking I do on the track. The test went well. I was able to repeatedly get the same pressure.




    That was good since I need to measure one wheel at a time, duplicating the pedal pressure is key to a good data set for all 4 corners.

    It was getting late so tomorrow I will measure each corner to get a baseline. Then I'll start tweaking the adjustments to see what kind of range I have.
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  8. #728
    Senior Member johngeorge's Avatar
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    man I cannot believe you dont datalog front and rear pressures! just sayin I do
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    We do as well. One of the guys on the team owns a company that is getting ready to release a product that will turn your tach into a brake bias gage. We have been testing it for the past 3 years and it works very well. We do notice slight variations, which are attributed to the fact that we are running the cheaper master cylinders, but it works REALLY WELL. The sensor can also be used to data log brake pressures and tells you the maximum pressure that the system saw since last being reset on the tach as well. So while the data logging function is there, many will just use the tach feature to get the info they need. Look for it shortly from Tel Tac.

    EDIT: I talked to the company owner about the product and asked why it was not released yet and he said that it is because they are finalizing a smart phone user interface, so you may not need a stand alone data system to record readings, I don't really know. Maybe he was just talking for setup. Anyway, the phones are amazing tools, and I can't wait to see the finished product that we helped develop with the FFR PDG GTM.
    Last edited by crash; 04-24-2015 at 10:29 AM.
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  10. #730
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    Quote Originally Posted by crash View Post
    We do as well.
    Quote Originally Posted by johngeorge View Post
    man I cannot believe you dont datalog front and rear pressures! just sayin I do
    Oh now everybody has brake pressure telemetry

    But I agree I do need to add it. My current setup is CAN based so I need to add a few sensors.

    It's on the list.
    John
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  11. #731
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    3 tracks in 6 days

    I was lucky enough to get lots of track time this week.

    I visited New Jersey Motorsports park lighting and thunderbolt then drove down to Virginia International Raceway.

    Lots of testing and some very good information.

    I am 100% sure that anyone who reports their GTM is unstable above 150 never set their rear bump steer.

    It's not something an alignment shop will normally do but it's critical on a GTM. The super stiff chassis will translate any misalignment and it's very noticeable above 150.

    With the bump steer set, I was able to remove most of my rear toe in with only 1/8 total toe in.

    If you plan on tracking or doing 1 mile events with your GTM you must set the rear bump steer.

    Check out all the Factory Five cars at VIR! By Saturday AM we had 7 factory five cars in our pit area.



    Hyper Fest was great. We took a helicopter ride after the race on Saturday.



    I can see my car from here!



    John
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    Good news on your setup, thanks for sharing. I knew the rear bump steer was huge, I don't know why the guys on the Corvette forum don't seem to be able to figure it out. For years you can find thread posts of them doing strange things from the rear suspension.

  13. #733
    Senior Member mikespms's Avatar
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    Hey John,

    Sounds like great time, do you have any track time video? Are you using the corvette toe links in the rear and if so did you use a corvette bump steer kit? How about your dry sump system did you get it dialed in and how is the sequential trans working?

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    Quote Originally Posted by fastthings View Post
    Good news on your setup, thanks for sharing. I knew the rear bump steer was huge, I don't know why the guys on the Corvette forum don't seem to be able to figure it out. For years you can find thread posts of them doing strange things from the rear suspension.
    Hi Gene,

    I agree with you, I think the internet has quite a few stories about people who chase the wrong things to setup the corvette suspension.

    C5 and C6 corvette racers definately know the story. The corvette suspension is just too compliant for track use.

    Soft rubber bushings that get worn out lead to most of the problems on the street. A suspension that changes adjustments becuse of the soft bushings is always a bad thing. The car was setup out of the factory to be cushy and smooth.

    On the GTM with a super stiff chassis and lots of traction with sticky tires its even more magnified.

    The hard parts from the C5 are very good, they just need to be rebuilt and or upgraded then well adjusted after you put them in the GTM.
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    John,

    Great info on the rear toe link issues. I am in the process of implementing Mike's front control arm upgrade but the rear link upgrade is next on the long list of suspension upgrades.
    Cheers,
    Dave

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    You got the life of a rock star, cool fun.

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    Quote Originally Posted by mikespms View Post
    Hey John,

    Sounds like great time, do you have any track time video? Are you using the corvette toe links in the rear and if so did you use a corvette bump steer kit? How about your dry sump system did you get it dialed in and how is the sequential trans working?

    Hey Mike I was lucky enough to get some views from outside my car this week. So yes I will post some video. The dry sump pressure is much lower now at 45 psi idle and 70 psi at redline. ARE were very helpful and the fix was simply clipping a few coils off a detent spring.

    I did upgrade the rear toe Links and added a rear bump steer kit.

    This is an old picture but it shows the toe links



    The transmission has been working great but I think I might have worn out the third gear engagement fingers or dog rings.

    I'm going to pull the transmission to check it out this weekend.
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  18. #738
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    Quote Originally Posted by fastthings View Post
    You got the life of a rock star, cool fun.
    Ha ha. I wish. The rock stars show up with tractor trailers and a pit crew. We had a bunch of them this weekend. Im the driver, mechanic and pit crew. Not very glamorous, but doing it all yourself has its own rewards.
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    I know you said it's an old picture, but you did put the lower sway bar mounting nut back on, right?

    Also, I would be VERY surprised if you have worn out any dogs on your Mendeola transaxle. We abuse the heck out of our gear boxes for dozens and dozens of hours and have done that for YEARS now. In all that time we have experienced ONE dog failure and it was during this last years 25 hour event. It was a major failure of the entire slider, but the transmission just kept going. It was truly amazing.

    When we first tested the Mendeola sequential dog box, we essentially had a free demo box to try out. Myself and another driver were tasked with driving it as hard as we possible could for about 8 hours of drive time to see if we could break it. I shifted with no clutch, ground the dogs MANY times, missed gears, etc. etc. and then we opened up the box to see nothing but a few chips out of the faces of some of the dogs. I have never been so brutal on a gear box and seen such little damage. The Mendeola's are STRONG.

    In any event, I don't know how your bodywork clearance is, but for us, we can pull the box apart with it still in the car. This may be easier for you or it might not, but the tear down of the transaxle is very simple, especially if you are just pulling the stack out to check things out. Ian should be able to walk you through the roughly 5 steps to pull the gear box down.

    What is much more important for us, and the gear boxes are pretty particular with this, is the adjustment of the shifter stops. If you get this wrong or if they get a little out of adjustment then the gear selections will not happen smoothly and sometimes the box will pop back down to the previous gear because it wasn't fully engaged in the next gear. I cannot stress this enough. If you haven't already, pay particular attention to your shifter stop adjustment.
    Last edited by crash; 05-05-2015 at 08:22 AM.
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    Quote Originally Posted by crash View Post
    What is much more important for us, and the gear boxes are pretty particular with this, is the adjustment of the shifter stops. If you get this wrong or if they get a little out of adjustment then the gear selections will not happen smoothly and sometimes the box will pop back down to the previous gear because it wasn't fully engaged in the next gear. I cannot stress this enough. If you haven't already, pay particular attention to your shifter stop adjustment.
    Hi Crash,

    HA HA yes, I did put the sway bar nut on.

    Your comments about the shifter adjustment are very interesting. Ian actually mentioned that he would call you as he thought you had experience with this.
    My hunch was that its an adjustment thing, but I was focusing on the cable throw and cable free play and the position of the cable attachment on the flag that the cable attaches to on the transaxle itself. When none of the adjustments I made fixed it I figured id check out the internals.

    I tried many many combos over the past 5 days and none were able to resolve the issue I have in third gear. I did not however adjust the shifter stops… come to think about it. I only had this issue after one of the shifter stops backed out and actually prevented me from shifting up a gear.. that was scary ! This all happened back in March. I thought I really broke something that time.. only after I was in the pit did I see that the adjuster had backed out. I tightened the stops and it shifted again , but it was not the same.... but maybe it was the adjustment I had made to the shifter stop that was the cause of the whole thing! I did not make the connection.

    I must have been lucky with my first shifter setup and install because it just worked flawlessly without adjustment.

    If you are right that would be AWESOME! Luckily I can make it happen on the street under 50 mph so I can just test it around my neighborhood. I love the transaxle. I am reasonably gentle on it most times and the oil never shows any significant metal.. It did not make sense that there was a failure however I did not know what to check next.

    Thanks a lot for the tip .
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    If you are running a cable shifter I would bet that it is an adjustment issue. This is one of the specific reasons that we DON'T run a cable shifter. They tend to go out of tune with cable stretch. The other reason is so that we can feel things transmitted through the solid shafting better.

    With using a cable shifter I would be highly tempted to put the shifter stops on the flag at the gear box. In this way it wouldn't matter where the actual hand held shift lever ended up, the flag would move to where it was supposed to be and no further. This would have more wear on the cables, but it would eliminate the issue of the shifter stops going out of adjustment.
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  22. #742
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    Quote Originally Posted by crash View Post
    If you are running a cable shifter I would bet that it is an adjustment issue.
    Again Crash,

    Your experience is most helpful.

    I understand the rod shift solution as that would make for both a more positive shift and as you say it’s not going to change. Especially important for 25 hours of driving without adjustment. And it also explains why in my experience hot cables shift slightly differently than cold cables.

    I think I would go with the rod solution like you have before I did the stops at the flag, but we will see.

    As long as I understand what the adjustment does and how my adjustment changes the behavior of the transaxle ill be fine. Until now I had no idea why my adjustments were not fixing the problem.

    As I think about all the adjustments I made, I realize based on what you have said that none of them worked because none of them actually changed anything that mattered regarding this problem. The shifter stops were always allowing full travel of the flag at the transaxle. I actually made a point to make sure I got all of the throw available. Sounds like that’s exactly NOT what I should have done. HA HA I have proven you can NOT fix this issue by maximizing the flag motion.

    Sure will be nice if all I need to do in order to fix this is turn an Allen head bolt to adjust the stops for the shift leaver throw.
    Last edited by kabacj; 05-05-2015 at 04:44 PM.
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    If you go with the rod solution make sure you use aircraft U joints. Again, there is a huge difference in performance and the ability to stay in tune over long periods of time. I used 3/4" 4130 rods and I think PDG uses 1/2 or 3/4 solid aluminum rods. Try to avoid any bends in the rods. This was much easier for us because the center steer driver placement means that the shifter is almost right in line with the flag on the transaxle.
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    Here is a quick video from my telemetry. Notice how the Go Pro loosened up. That is what happens when you mess with the camera while you are sitting in the car waiting for the session to start.

    Hopefully Jim in the blue and yellow challenge car in front of me got some good go pro footage. Also you can see how I was struggling with the shifting. I would just keep banging away till the shift indicator said the right gear. Definitely used up some of my attention, but I was still able to put down a decent qualifying time.

    Last edited by kabacj; 05-05-2015 at 08:48 PM.
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    wow! very cool John. Ill look at Jim's quali video tonight, but only have the front camera as the rear I forgot to get from David the Koni guy.
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    Is that Jim Schenk in the Blue/Yellow FFR? Wonder if he feels a little weird being chased by a guy in a car that he designed

    Martin
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    After watching that I am just about 100% sure this is an adjustment problem. Notice how the issue is only on down shifts? If this was a dog problem you would have an issue where the transaxle would pop out of gear when you went from acceleration to deceleration. This is not happening. What is happening is that you are simply not getting enough throw on the shift mechanism. The bad part about this now is that you may have had this happen enough that the shift forks are now pushed out of alignment and the stack may need a tune up. This is something that is particular to the sequential because on the H pattern boxes it really doesn't matter because you can just move the shifter further to compensate for fork misalignment. Unfortunately, because the fork is moved with a precision drum in a sequential style box, once that gets out of tune the only way is to open the box up and make the adjustments. I would highly recommend that if you try adjusting the stops on your shifter and this issue is not resolved, that you send the box back to Mendeola for a tune up.

    There is really only one thing that you can do to these boxes that will cause them grief and that is to not get the sliders fully engaged before you try and apply throttle. This tries to forcibly push the dog rings apart while the fork and drum system is still trying to push them together. This can cause problems with bent forks, or forks that become out of tune to the shifting drum.

    Didn't look like you were on slicks? If you were they were pretty forgiving.
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  28. #748
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    Quote Originally Posted by Martin View Post
    Is that Jim Schenk in the Blue/Yellow FFR? Wonder if he feels a little weird being chased by a guy in a car that he designed

    Martin
    I think he is happy. He has been a great help getting the car setup.

    It's like watching your kids grow up.
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  29. #749
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    Quote Originally Posted by crash View Post
    After watching that I am just about 100% sure this is an adjustment problem. Notice how the issue is only on down shifts? If this was a dog problem you would have an issue where the transaxle would pop out of gear when you went from acceleration to deceleration. This is not happening. What is happening is that you are simply not getting enough throw on the shift mechanism.


    Didn't look like you were on slicks? If you were they were pretty forgiving.
    Hi Mike,

    Well let me give you a bit more data to go on.

    I was having issues on down shifts and yeah I agree that’s probably an adjustment thing.

    What you might not have noticed in the vid is that I am shifting around any point when I am decelerating in 3rd gear. It puts me in the wrong gear for a few corners, but I just deal with then over slow down grab second, rev to the moon or I lug 4th.

    Its not that the trans pops out of gear when I am in third, but its not fully in gear when im in third decelerating. I get lots of feedback through the shifter as the trans is almost in gear, but not. From what Ian was saying the dogs have ramps that will pull the gear into proper registration on acceleration under load I don’t get that benefit when decelerating. So I can grab third on an up shift from second but not grab and stay in third on a down shift from forth.

    So it still might be an adjustment issue.. at least I hope it is.

    Regarding the slicks I'm on them. Ha yeah im pretty busy in there even tho you don’t see it. During the down shifting I am fully clutch in so no deceleration from the motor I’m just braking then feathering in the clutch in to get the down shift to take when I see the right next gear indicated. Tricky so I don’t break the tires lose mid corner. Lots of fun 
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    GTM # 344
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  30. #750
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    Right, the dogs have ramps. The issue is if you do not engage enough to get to the ramp area then bad things happen. I think this is your problem. I would be highly surprised if you have damaged the dogs to the point that they no longer have a ramp and therefore will no longer hold the dogs together during accel/decel. And just to clarify, the dogs have ramps on both accel and decel sides. This is what keeps the slider engaged during both acceleration AND deceleration. Yes there is a time when neither ramp on either side of the dogs are engaged when transitioning from accel to decel, but unless there is a force trying to pull the slider out of position, no issues will be noticed.

    Again, this sounds to me like an adjustment issue, but likely may not be one that can be addressed by just adjusting your shifter stops at this point. Without getting into the nuances of the Mendeola gear box, the shifter just "suggests" what gear the transaxle should be in and the internal drum and shifting mechanism then tries to ensure that the correct gear is engaged. There are really two things that can go wrong here.

    1) The shifter cannot move the star wheel within the gearbox to the tip over point where the drum mechanism takes over and tries to put the slider into the proper gear, or

    2) The shifter goes far enough to get the drum working properly, but because of an event that bent a fork or knocked the fork "out of tune" to the drum, even though the drum is doing what it is supposed to do, the fork is not moving the slider so that the dogs reach a tip over point where the pressure angle of the ramp takes over and holds the slider engaged.

    Again, number 1 is easy enough to look at and try different adjustments. Number 2, however, requires some pretty significant work to correct. Note that number 1 can lead to number 2 in very short order. This is why it is CRITICALLY IMPORTANT that the shifter be set up properly as far as stops are concerned from the beginning. In the case of the Mendeola design, it is okay, and even preferable to adjust the stops so that the flag goes a bit past the star wheel tip over point. Not WAY past, but a little extra throw will not hurt anything. Again one of the problems is that cable stretch will reduce the amount of throw you see at the flag over time and can quickly lead to both problems number 1 and 2 listed above.
    Last edited by crash; 05-06-2015 at 10:44 AM.
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  31. #751
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    Thanks again for all the info Mike.

    I am going to try the adjustment and also put a scope inside the case to see what I can see.
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  32. #752
    Senior Member mikespms's Avatar
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    Hey John,

    If you can get a good view of the ramp on the dog look and see if the edge is shiny and rounded and compare it to another gear,once they get to rounded it will not stay in gear. If is not jumping out of gear it is most likely adjustment.

  33. #753
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    John,

    At one time I devised a method of confirming the fork engagement vs drum rotation using the sender for the gear indicator output as a degree wheel for the drum. With the motor stopped I logged the voltages while centered in each gear, then the voltages of the engagement points for each gear on up and down shifts. The engagement point was found by moving the axle to a position where the dogs were misaligned and would NOT engage while applying light pressure to the flag. I found the readings were very consistent for each gear on a fresh box. I never got a chance to test a well used box to see if the positions changed. The theory is if a fork was damaged it would engage at a different rotation on the drum.

    Some experience with PDG shifters as I recall:

    When we first ran the Mendeola we adapted the linkage from the G50 which was mostly derived from kit components. It used the kit shifter and needle bearing ujoint (modified for straight line motion only) which adapted to a 3/4 .062 wall 4130 tube with a few bends, went to an a-frame linkage (near the oem starter location) secured with 2 ea 1/4" rods with female 1/4 heims. A surplus pin and block 3/4 ujoint connected the back section (3/4" straight .062 wall mild steel) which then used a kit 1/2" pin and block ujoint fixed to a bracket on the flag. Stops were made using a 1/4" threaded rod and heim also connected to the flag.

    The result was our first race (a 6 hour) went ok but at the second one (a 3 hr) the 1/2" kit p&b ujoint failed. I then concluded that the mass of the whole shifter system put a lot of stress on the stops and rearward joints and decided to move the stops up front to the shifter.

    The current setup still uses the kit shifter and needle ujoint (with the cross modified to allow only straight line travel), somewhat bent 4130 tube past the engine to a pivot attached to the oem starter bosses) then a 3/4" solid 6061 rod with 5/16" heims at both ends. The flag is filled an drilled for a 5/16" bolt. The stops are at the front and are a long 1/4" rod passing through a drilled stop with washers and rubber washers to add some cushion.

    This setup has lasted for many seasons and only required stop adjustment when the gearbox was changed and used different internal ratchets. Bends in the 4130 tube don't cause any issue as the path overall is fairly straight. It passes under the aluminum motor mount to avoid the oil pump. In your case to adapt to LH driver position perhaps a cross shaft at the firewall could transfer the motion to the outside of the motor.

    Mike prefers and did install a system with stops connected to the flag, but my concern was that the relatively heavy mass of the linkage transmitted thru the flag impacting the stops could cause the flag attachment setscrew to loosen or wear the shaft bushing. Perhaps some cushioning on the stops as I have done with the front mounted stops would temper this impact.

    If the cable is retained, stops at the rear would work fine, perhaps a cable upgrade might help. I know team QRP found some much higher quality shift cables that improved their shifter.

    Keep up the great descriptions, they're very informative.

    Jim H
    Team PDG

  34. #754
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    Thanks for the info Jim H and Mike P

    It sounds like I'll eventually build in rod actuated shifting. Your experience is very helpful.

    I hope that if I can manuver the scope into the right position I will be able to see the drum, forks and dogs work.. Or not work.

    With that information setup and adjustment will be much easier.

    Shipping the trans back to California is a three week turn around. That's too long mid season. Ian at Mendiola has always been super helpful. Maybe I can fix it myself if it comes to that.
    XTF #2
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  35. #755
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    As a result of the handling improvement I saw over the weekend i was able to break the 160 mph barrier on the back strait at VIR.

    I formerly was running ½ inch of total toe in. That most likely masked the fact that the rear bump steer was not set properly. Prior to my last track visit I did not realize how important bump steer was to set. When the bump steer is properly set I got better traction off the corner and better high speed stability.

    Below is a screen shot of my telemetry. I am sure there is another 5-10 mph in the car, as soon as I get the transaxle sorted and I can really charge into the turn and carry more corner speed. Every MPH I carry through the coner is less I need to build down the strait.


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  36. #756
    Senior Member johngeorge's Avatar
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    wow, 20mph faster then challenge cars.. damn thats moving.
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  37. #757
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    Awesome, I just heard that gps is going to be improving, we will get accuracy down to the centimeter.

  38. #758
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    Great to see John.
    Measurable improvement feeds the soul!
    Its amazing how quickly this car can build speed :-)
    Cheers,
    Dave

    GTM # 294 Build Start Date 10/12/2009,
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  39. #759
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    Quote Originally Posted by Fraser D View Post
    Great to see John.
    Measurable improvement feeds the soul!
    Its amazing how quickly this car can build speed :-)
    Thanks Dave.

    Exactly right. As long as I am faster at the end of every track day I am happy.

    This past weekend was a big improvement.

    John
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  40. #760
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    awesome progress, when's the next track day?
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