42056 - Porsche 911 GT3 RS - MODs and Improvements

[Blakbird]

I've installed several of these mods now and am quite happy with them. First, of course, was my own step 5 mod and then Crowkillers' gear order mod. Then I did the mods for Jetro's removable body.

The next thing I did is supertechnicman's fix for the continuous gear shifting. Very elegant and simple.

I reversed the direction of the changeover catches in the shift module as recommended by Attika and it does indeed make the 90 degree stop points almost perfect.

Finally, I installed the HOG mod of Didumos69. This slips right into the space under the dash and is quite inconspicuous. However, I did have to make one alteration. A 3x3 T-shaped liftarm is required as shown or there is nothing to prevent the steering rack from slipping forward. After that, it really works well.

[Didumos69]

Did it make sense to you what I wrote?

This makes perfect sense to me! Thanks for clarifying!

Leaves me with one other question. Would it make any difference whether the two CV-joints are aligned with their splits having the same orientation or with perpendicular splits? It wouldn't suprise me if it did. Like I said CV-joints start behaving odd when angled more than 11 degrees.

In the section where the drive axle crosses the gear selecter axle there is also a pin joiner placed. Not that I think pin joiners are generally bad after the Blakbird fix, but I thought it would be worth trying without. I don't think the pin joiner is needed for keeping the bevel gear with pin hole in place and it does cause some unnecessary friction.

In LDD this pin joiner actually touches one of the drive axles. Besides that the pin joiner may have some friction with the adjacent bevel gear with pin hole. Nobody tried whether removing the pin joiner reduces friction even further?

Edited June 8, 2016 by Didumos69

[Didumos69]

Finally, I installed the HOG mod of Didumos69. This slips right into the space under the dash and is quite inconspicuous. However, I did have to make one alteration. A 3x3 L-shaped liftarm is required as shown or there is nothing to prevent the steering rack from slipping forward. After that, it really works well.

Thank you Blakbird for testing the HoG-MOD. I will add the 3x3 liftarm and the extra pins you used to the LXF-file and drop the bush . Then I will update my final post about it accordingly.

EDIT: Done, LXF-file here (also contains variations for removable HoG and for a gear rack at the back of the front axles).

Edited June 8, 2016 by Didumos69

[JunkstyleGio]

@Tommy Styrvoky:

Nice mod!

Thanks for using my Original LDD file.

To bad your MOD is a little to big for "The marriage"

[Tommy Styrvoky]

@Tommy Styrvoky:

Nice mod!

Thanks for using my Original LDD file.

To bad your MOD is a little to big for "The marriage"

could i have a file of the basic bodywork? As I have. A couple thoughts for tweaking it around the bodywork.

[Kumbbl]

After testing my version of MaxSupercars' mod some more, I decided it was crap. I don't like the crap it does in neutral, so it has to go. Clean slate. This time I basically worked on the rough version from Max' video into LDD and hid the lock behind both panels, because that was what I wanted to do in the first place. I think this solution actual looks better than my previous crap.

I couldn't figure out why the model has a 3x5 liftarm on the side, besides it adding support for the structure above it. The pinholes aren't used by the body that goes on top from what I can see. So I switched it with a 2x4 liftarm since I needed the space. I tested this mechanism on my mock up and it works.

And this how it should look on the model:

Thanks Max for the great idea!

Appie, could you please share you lxf-file version so i could check / test your mode?

[Appie]

Sure thing, more testing is always good. I tested this mod of Max in my mockup. There's a reason the 2L axle with axle connector is in front of the model: in case it needs extra bracing on top (there's a 3L pin with stopbush there anyway on the actual model), but I don't think it is needed, but perhaps your experience will be different.

Here's the file.

Edited June 8, 2016 by Appie

[Nmapladem]

Hello everyone

I'm currently testing with Mindstorm and it works excellently as much to do with electronics;)

Video :

Edited June 8, 2016 by Nmapladem

[MaxSupercars]

Appie that improvement of my blocking mechanism looks good! I have tested it in real and it works... ;)

Max

Edited June 8, 2016 by MaxSupercars

[Didumos69]

I think I have found a way to add a second limiter that directly applies to the selecter axle that operates the driving rings. This should make the positions of that axle more definite. In other words, it will help limiting the axle to 90° positions only. Perhaps this could improve the way the gearbox operates, avoid halting and reduce backlash in the switching mechanism even further. And hopefully this will make the 8-tooth gear on axle-pin with friction unnecessary, which was also meant to reduce backlash (the right one of the two 8 tooth gears at the upper left corner of the first image below). The limiter has been integrated in the section close to the gearbox where the gear selecter axle crosses the drive axle. I tested it and it works very well and does not generate friction on the drive axles. I also checked whether this fits in the chassis and it does. I don't have the bevel gear with pin hole so you have to imagine that part. This video tells the rest of the story:

EDIT: The 8 tooth gears used to add friction have indeed become unnecessary when this limiter is used. Or actually, they should be ommitted for the gear selection to work flawlessly, see this post. I also swapped the limiter to the left, so it doesn't collide with the reverse gear blocking mechanism from MaxSupercars and Appie.

The white silicon band could be replaced with a red one wrapped around the limiter twice. I don't know exactly how much torque the paddle selecter generates, so you will have to try what works better. Maybe using a red silicon band works better if you drop the friction-generating 8-tooth gear.

EDIT: Wrapping two white silicon bands around the two limiters turns out to do the job. These can be taken from the paddle shifters. With this mod the whole operation becomes lighter, so the paddle shifters can do with one silicon band each. Simply wrap it completely around the ball joint once to obtain the desired tension. See this post.

Now the question is, can somebody test this on the real model? If you would then here are some considerations to take into account:

- It's advisable to combine this with Blakbird's pin joiner fix and Attika's change-over-catches-fix.

- Try if the whole setup can do without the 8-tooth gear attached that was meant to reduce backlash.

- Make sure the bevel gear with pin hole has enough play.

- Make sure the angle element and the two added bushes sit tight - not too tight - against the frame so the selecter axle won't be tempted to push the angle element against the bevel gear with pin hole.

The original and modified construction:

The added (transparent green), reused (original color) and dropped (transparent red) parts:

LXF-file here.

Edited June 16, 2016 by Didumos69

[Attika]

I think I have a way to add a second limiter that directly limits the selecter axle that operates the driving rings. This should make the positions of that axle more definite; it will confine it to 90 degree positions even further. Perhaps this could improve the way the gearbox operates and reduce backlash even further. It has been integrated in the section close to the gearbox where the gear selecter axle crosses the drive axle. I tested it and it works very well and does not generate friction on the drive axles. I don't have the bevel gear with pin hole so you have to imagine that part. I think this video tells the rest of the story.

The white silicon band could be replaced with a red one wrapped around the limiter twice. I don't know exactly how much torque the paddle selecter generates. Now the question is, can somebody test this on the real model?

I find it a remarkable idea. Wow. There is much more in this concept, than just fixing this issue. Great!

Edited June 8, 2016 by Attika

[Victor Imaginator]

I just fail to resist this Porsche mania and build my own one) Stopped in the middle of the box #2 because i ran out of 5x7 technic frames) Only mod i make - is to change gears for proper shifting sequence. And all works perfect. Changing new transmission connectors without ridges to old white with ridges is making gear shifting slightly difficult, but not impossible. It's just works) And i don't make Blackbird's mod of step 5 - no friction problems at all, white clutch gear never engaged while i'm testing it in all modes at all gears. But i noticed one thing that i want to share... When i making something that involves using gears or may cause friction i can sliding things by fractions of millimeters much time until all spin freely, so, at step 8 two Z16 gear added and they can generate friction with black U shaped part. And you noticed it, and make gear rotate freely, but then, at step 18 big dark grey gear is added. And this gear sitting on the axle much more tight than Z16 gears, and when you just puch it to the axle - it force Z16 gear to touch black U-shaped part again. And it can be fixed here. Also it can be fixed later through small open window at the bottom of the car.

[Appie]

Appie that improvement of my blocking mechanism looks good! I have tested it in real and it works... ;)

Max

Cool, glad you like it. Thanks again for the great idea in the first place.

[phattyg]

Hi all, this seems like a fantastic collection of mods, especially as outlined on the first page. Would there be any way to index all the pieces/parts needed to make all of these mods? Looking to buy the pieces so as to fully mod my car to include all of these.

Great work everyone!

[Tommy Styrvoky]

Hi all, this seems like a fantastic collection of mods, especially as outlined on the first page. Would there be any way to index all the pieces/parts needed to make all of these mods? Looking to buy the pieces so as to fully mod my car to include all of these.

Great work everyone!

my guess is that there will be eventually a master set of instructions containing most of the mods, possibly like the ultimate 42009.

[Kumbbl]

This video tells the rest of the story:

This is ingenious! :thumbup: :thumbup: i'm quite sure i will build in this cute 90 degree indexer in my Porsche.....

[nerdsforprez]

Thanks to everyone who is adding to this thread. My model is ordered and I will just play the waiting game until it arrives. In mid summer, likely about the time that my model arrives, I have to travel for work and will not be home or in my Lego lair for several months. This set will hopefully give me some outlet as I am away however. I plan on building a true "ultimate" set.... with all the upgrades that are on this thread and several of my own. I am already lamenting the fact that I have used most of my black 3l pins. I have thought, so many times while building, "leave these alone, I can use them elsewhere" but am sad to report I never heeded those thoughts. Although I still have many, I have nowhere near the amount I once had.

[efferman]

Till my porsche is arriving i have to play with ideas. The first one is to move the ratchet mechanism into the frame to give long legs more room

[Appie]

That's pretty sweet efferman.

Back to a concept I had considering I routed a steering axle to the rear of the car already for my HOG, I started to look for a spot to house gearrack for rear wheel steering. Besides the entire rear suspension needing a redesign to accomodate steering obviously I need space for that crucial part around the diff. I think I found it.

This is a very rough version. I'd work on it some more, but my LDD keeps crashing and I have other stuff to do for the next couple of days that it might be better if somebody else took a crack at it. Things I would need to adjust were:

- Gear on the front steering needs to be bigger so the rear gets a small turning radius.

- Perhaps a rack with 8T gear at the rear.

- Compatible with dash HOG

- Compatible with other MODs already in place (Max' gearlock and the like)

- Need new connection point to fix the top of the engine to the rear of the car since current spot of rack uses the old connection point.

- Probably some other stuff I forgot.

If anybody wants to take a crack at it, here's the LDD, if not, I'll do it myself sometime next week.

[phattyg]

I made all the mods as listed above...but for some reason I get an awful lot of torque in 3rd gear. Gears slip and click. I undid the very first change for swapping the gearbox order 1-2-3-4 back to 1-3-2-4, and it seems to work normally. Went through all of the gears and pieces, and it seems that maybe it's due to lack of support of those back axles that determine 2nd vs 3rd gear? Any ideas?

[__________________________]

Someone will eventually compile all of these mods into one master version of the set, i hope, lol

[Tommy Styrvoky]

I was thinking about replacing the shifting mechanism with something similar to Piterx's design,as moving the entire shifting mechanism would work, but it's rather large, and to route the linkages may take up needed space.

[Trace17]

I think someone mentioned it before, but there is something strange with step 121 and step 173 of the BI, which might cause differences. In step 121 one of the CV-joints is inserted in a 2L axle connector. However the CV-joint is oriented perfectly horizontally, while the 2L axle connector is rotated by 45 degrees, just like the knob gear attached to it at the other end. In fact step 121 shows something impossible. Most of us will leave the knob gear in 45 degree position and will end up having the CV-joint in rotated position too. However you can rotate the CV-joint clockwise or counterclockwise. This is where the first difference might occur. Further on in step 173 the CV-joint coming out of the paddle selecter - which is oriented perfectly vertically - is connected to the CV-joint that was put in place in step 121. Step 173 shows how the vertically oriented CV-joint is connected to the horizontally oriented CV-joint. In practice this might turn out differently, because of the first CV-joint being rotated by 45 degrees.

So you could end up with the CV-joints having the same orientation or different orientation. I've been playing with CV-joints and when they are angled more that 11 degrees they start grinding. So I don't trust them and therefore I wouldn't be surprised when their relative orientation matters in the whole gear selection setup. So I'm very curious whether the CV-joints in your builds have the same orientation or different orientation.

EDIT: Now that I'm looking into this I'm wondering, how can tthe whole gear selection mechanism operate properly if somewhere down the road a 90 degree oriented axle connects to a 45 degree oriented axle? Where have these 45 degrees gone? What am I missing? Or is this 45 degree difference what's needed to avoid backlash? But then the above possibilities might make the difference between adding backlash and reducing backlash. Could somebody clarify?

Remarkable side note; Step 173 is the last step showing the CV-joints. In the remaining 683 steps you don't see them again...

Nice finding. I've been straight jumping into my porsche to find something. There isn't anything, or at least it has no effect on the outcome. The paddle shifter mechanism operates only with knob wheels right down to the actual rotating shifting axle. So follow it on its way:

1. Due to the nature of the paddle shifter the knobwheel in it (the upper middle on the vertical axle) should be always + (+ means pointing in the "noble" directions, ahead, backward and the two sides 0,90,180,270)

2. So the next knobwheel what connected to it (on the horizontal axle at the bottom of the paddleshifter) is always x (x means the 45,135, 225,315 pointing) (I hope you get what I mean)

3. Here comes the two cv-joint going backward keepeing the x position.

4. That gives us that the knobwheel behind the 8 tooth gear is also in x position

5. What makes the last knobwheel on the actual shifting axle being always in + position. Just as it is desired by the design.

So my conclusion is: On the picture the knobwheels are ok. And it is a 3d modeling mistake the the cv is in an impossible position, BUT when you physically build it, you can't go wrong as the whole system conains only elements what can only be turned only by 90 degrees (knobwheel, and cv)

I'm surprised to say this, but this time the designers did well, and whoever made the pic for the instruction messed up the picture. But it can't make anyone to go wrong at the building procedure.

Did it make sense to you what I wrote?

edit: when I say "always" that means the resting system in any gear

This makes perfect sense to me! Thanks for clarifying!

Leaves me with one other question. Would it make any difference whether the two CV-joints are aligned with their splits having the same orientation or with perpendicular splits? It wouldn't suprise me if it did. Like I said CV-joints start behaving odd when angled more than 11 degrees.

Preface: I'm no technic expert so I'm trying to use terminology used in the above posts.

I just got to this step tonight and I was baffled by the 2L axle connector (the darker grey "receiving" piece) is at a 45 degree angle but shown at 180 horizontal in the instructions. I believe as Didumos69 mentions above that this is an impossible configuration. So my question is, do I need to leave it in this 45 degree configuration, rotate it 180 (so it's at the other 45)? Or something else?

And do I need to do anything special to compensate for this when building the next gear selection unit through 173?

Reading Attika's post makes me think I should leave it all as is and continue.

Here's my current progress:

Edited June 10, 2016 by Trace17

[Tommy Styrvoky]

Preface: I'm no technic expert so I'm trying to use terminology used in the above posts.

I just got to this step tonight and I was baffled by the 2L axle connector (the darker grey "receiving" piece) is at a 45 degree angle but shown at 180 horizontal in the instructions. I believe as Didumos69 mentions above that this is an impossible configuration. So my question is, do I need to leave it in this 45 degree configuration, rotate it 180 (so it's at the other 45)? Or something else?

And do I need to do anything special to compensate for this when building the next gear selection unit through 173?

Reading Attika's post makes me think I should leave it all as is and continue.

Here's my current progress:

I don't think it should cause any problems to place the parts in either orientation, CV= Constant velocity joint, so it is designed to function correctly, until it reaches it's maximum travel, then it can have problems locking. With the error in the instructions, it will align itself when you shift the gearbox.

[Didumos69]

Reading Attika's post makes me think I should leave it all as is and continue.

That's also what I understood. I think you can leave all as is and continue. I also tested whether it makes any difference how the CV-joints are aligned with the angles that are used, but it doesn't. The whole thing operates in 90 degree steps so it doesn't really matter how you eventually connect this CV-joint with the one attached to the paddle shifter unit.

EDIT: didn't see the above answer, but boils down to the same...

Btw, did you apply the essential improvements listed in the original post? A few of them are mission-critical.

Edited June 10, 2016 by Didumos69