Sgt.Speirs 1253 Posted December 29, 2021 Hello, and welcome to Sgt.Speirs‘ King Cab - TRF201 Transmission Conversion build log for the Nissan King Cab / Hilux Monster Racer. =========================================================== To skip directly to the final pics, parts list and manual: >> CLICK HERE << =========================================================== In the early 90s, two of my friends had a Nissan King Cab (and they still have them). Although I think the Hilux Monster Racer looks better, the King Cab has a special place in my RC memory. NISSAN King Cab - Tamiya Guide Book 1995 TOYOTA Hi-Lux Monster Racer - Tamiya Guide Book 1995 Four weeks ago I found a local offer of a King Cab chassis for a good price (65€). No wheels/tires, no body, but blue sleeved dampers from the Dyna Storm and the carbon race steering set (53033). Only the body mounts referring, that it was previously a Nissan King Cab. Not related, but still nice...the Dyna Storm Overall, the parts are in great condition and even the bathtube chassis has no scratches as expected from heavy off-road trips. The rear dampers have some scratches from the spring/suspension, but they will work fine. The general weak point of the King Cab/Monster Racer, the ball differential, has a lot of wear and is hard to move. Unfortunately are spare parts hard to find. Because this car is planned as a runner, I decided to replace the gearbox by a current one (incl. a slipper clutch) with a probably better spare part availability. 1st proposal - The gearbox of the Super Astute (Re-Release): The King Cab shares its gearbox with the (Super) Astute. The gearbox of the re-re Super Astute from 2018 would be a good alternative. But not all internal parts for the gearbox are currently available… 2nd proposal - The gearbox of the Dyna Storm: The Dyna Storm has also a slipper (Multi Disc Clutch system) and would be a proper solution. But there is the same issue with spare part availability than for idea same as for proposal 1. 3nd proposal - The gearbox of the TRF201: The TRF201 is currently no longer available, but the ball diff (not the diff joints) and the slipper clutch is shared with the new Super Avante. So spare parts will be no issue in the next years. So I decided to go with proposal 3... The TRF211XM uses the same ball diff. Optional there is a oil filled gear diff. Due to less maintenance, I wanted to try the gear diff…a mistake at the end. First I ordered only the gearbox to find out if it will work (enough space, position of the gear box outlets, wheel base,…). It does in my opinion... ...so I started modeling of the main chassis (bath tube), sub chassis (frp plate) and TRF201 gearbox in 3D, to create the brackets for the top and bottom mounting points. 11 Share this post Link to post Share on other sites
Kol__ 3377 Posted December 30, 2021 Awesome work! Looking forward to seeing how this develops @Sgt.Speirs Share this post Link to post Share on other sites
Sgt.Speirs 1253 Posted December 31, 2021 The idea of this transmission conversion is to use on both sides (gearbox and chassis) the original mounting points/holes (no modification on the chassis). On the gearbox: On the chassis side: In this case the standard FRP plate on the bottom cannot be re-used due to different positions of the mounting holes of the TRF gearbox. For the upper bracket: This shall to be designed, that the new gearbox has the same interface points to the chassis as the old standard King Cab gearbox. The first design of the bracket... ...and the real part made by 3D printer. In parallel, the ordered parts arrived: After the ordered parts arrived, I could make a first fit check between gearbox and chassis: First I've built the gear diff...and I found out that it is too thick and won‘t fit into the gearbox housing So additional parts for the ball diff has to been ordered. For the new FRP plate, I've had to check the width of the new gearbox. The width of the TRF gearbox (incl. the diff joints out) is 3.6mm less than the original one. That means for the new FRP plate that the holes for the suspension brackets must be on each side 1.6mm further inside. These mounting holes (suspension brackets) have to be also moved 4 mm backwards which increase the wheel base by 4mm. After comparing the positions of the lower mounting points of the gearbox between 3D and chassis, I had all the data to create the new FRP plate in 3D. 5 Share this post Link to post Share on other sites
Sgt.Speirs 1253 Posted January 4, 2022 Hello and also a happy new year! Let’s continue the worklog From the finished FRP plate in 3D, I made a cardboard jig to double-check all mounting point/holes: Subsequently I measured the final length of the bottom spacer to mount the gearbox with the FRP plate. The 3D for these spacer was done quickly (also the printing by the 3D printer): Next step was to cut out the FRP plate. I used a 3mm thick black FRP plate for this (0.5mm thicker than the original one). With the 2D drawing of the FRP plate and some toolings (jigsaw, files, drilling machine) the work was done in 2 hours: With the spacer from before I had all parts together for a complete fit-check in the chassis incl. suspension and motor. As expected, there were some (minor) issues 1.) When I decreased the width of the rear track by 1.6mm each side, I didn’t do this with the yellow marked sides of the FRP plate. In this case I had a clash with the suspension arms... With a file I solve this issue in 5 min: 2.) In the 3D I haven‘t modeled the suspension arms and the aluminum motor plate. Between both there was also a clash... This issue I could also solve by using a file. 3.) The last issue (until now) concerns the motor protection. The original can‘t be used due to there is no enough clearance between motor and FRP plate. Also the mounting points are now to close to the suspension brackets. Currently I have no solution, but this is for the first step also not necessary. I think about using/testing the TRF201 motor protection or a custom build aluminum plate. So now I can start the build of the chassis…I‘m looking forward 5 Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted January 4, 2022 This is brilliant. Some seriously impressive drill skills here. I would suggest the TRF201 motor guard. It attached to the two holes on the top of the transmission case, and I'm sure at the bottom you could like a little bridge plate to attached it. You need to DN01 or TRF201 B Parts tree. 1 Share this post Link to post Share on other sites
Sgt.Speirs 1253 Posted January 4, 2022 (edited) @ThunderDragonCy: I will go your suggested way. Because I can use the two upper holes (as you mentioned) and because I found a further issue, which force me to re-design the upper bracket. This give me hopefully on the bottom more space for the TRF201 motor guard or for a bridge plate. The issue itself is no show stopper, but frustrating that I didn‘t considered this. I'll let you share it tomorrow. Today I was too disappointed to made photos… Edit: Order about the B-parts tree is done… Edited January 4, 2022 by Sgt.Speirs 2 Share this post Link to post Share on other sites
jonboy1 2943 Posted January 5, 2022 Fantastic build - you're combining 2 of my favourite models in one! There's a lot of confusing info about the gear diff options for the TRF201 - the TA06 only works with the TRF201 Mid - the gearbox is wider with this version. You can fit the Kyosho Ultima gear diff https://wheelspinmodels.co.uk/i/225425/ which still requires removing the ribs from the inside of the gearbox cases. I can confirm this definitely works as I've got it in my TRF201/Zahhak. http://www.oople.com/forums/showthread.php?t=85278 One thing I did notice is you don't need to remove any of the inner ring for the bearing, despite it showing it needing to be in the picture. The other option is to get the gear cases @ThunderDragonCy designed which will take the TA06 gear diff Keep it coming though - would love to see how this comes out! 1 Share this post Link to post Share on other sites
Sgt.Speirs 1253 Posted January 5, 2022 As mentioned yesterday the current issue. The motor can clashs with the suspension pin. With a 20T pinion gear (10.27:1 gear ratio), the pinion gear don't reach the spur gear: I don't have any other pinion gears here with more teeth to test which fits. But I also don't want to use higher pinion gears due to the gear ration will be out of range as for the King Cab Chassis proposed ratio (from 1:10.30 to 1:13.93). With shimming the complete gear case by 1mm the pinion gear fits better in the spur gear, but not 100% perfect. I have decided to move additionally the rear suspension brackets 2mm in forward direction (and decrease the wheel base by 2mm). Then pinion gear and spur gear fits perfect. In this case (creating a new FRP plate) I can also implement the attachement of the motor guard. I think about a small notch in the FRP plate for the TRF201 motor guard and a longer bottom spacer on the rear side of the gear case. Then I can mount the motor guard with the bottom spacer/FRP plate. @jonboy1: I go forward with the standard TRF201 ball differential. It's the same (should be the same) as the ball diff for the Super Avante (22025 - TD4 Ball Differential Set, as spare part this year/spring available). But thanks for the infos about alternative gear diff solutions 4 Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted January 5, 2022 Glad you got the motor sorted out. Worth noting that the Kimbrough B4 spur gears fit and they do 81, 84 and 87t options. Not sure if they would fit under the cover though. Share this post Link to post Share on other sites
Sgt.Speirs 1253 Posted January 5, 2022 (edited) @ThunderDragonCy: The cover has a inner diameter of 46mm, the 79T spur gear a outer diameter of 42.7mm. Not much space for a bigger spur gear, but as a last resort an option. Thanks Edit: Do you have informations about the outer diameter of these spur gears? Edited January 5, 2022 by Sgt.Speirs Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted January 5, 2022 Try this https://ultrascale.uk/node/15 Share this post Link to post Share on other sites
Grumpy pants 4485 Posted January 5, 2022 Fantastic work and thread 👏 Share this post Link to post Share on other sites
Goudar 526 Posted January 5, 2022 10 hours ago, jonboy1 said: The other option is to get the gear cases @ThunderDragonCy designed which will take the TA06 gear diff I got a HILUX Monster Racer to rebuild, this will work without any modifications ? All you need is that gearbox and TA06 balldiff ? Maybe heat motor plate ? I'm currently looking for a solution, cause I would like to run this lovely car without any issue. Good luck with your labor of love @Sgt.Speirs Share this post Link to post Share on other sites
Sgt.Speirs 1253 Posted January 5, 2022 @Goudar: ThunderDragonCy designed a gear case for a TRF201/DN01 in which the TA06 gear diff can be used. Normally you can use in a TRF201 gear case only the ball diff. The gear case of ThunderDragonCy and/or the original TRF201 (TA 19004269) will NOT work without any modifications/or additional parts with the King Cab/Hilux Monster Racer chassis. @ThunderDragonCy: Please correct me if I am wrong. 1 Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted January 5, 2022 2 hours ago, Sgt.Speirs said: @Goudar: ThunderDragonCy designed a gear case for a TRF201/DN01 in which the TA06 gear diff can be used. Normally you can use in a TRF201 gear case only the ball diff. The gear case of ThunderDragonCy and/or the original TRF201 (TA 19004269) will NOT work without any modifications/or additional parts with the King Cab/Hilux Monster Racer chassis. @ThunderDragonCy: Please correct me if I am wrong. You are correct. My gear case for the TA06 gear diff on the TRF201 is simply a 5mm wider version across the bearings. All the mounting points are the same. 1 Share this post Link to post Share on other sites
Goudar 526 Posted January 5, 2022 Thanks for you answer. I need to find another way then. Share this post Link to post Share on other sites
Sgt.Speirs 1253 Posted January 7, 2022 That ordered TRF201 B-part tree arrived today. Also some spare parts as reserve. The first impression looks good, also the bottom side. I‘m very confident that the motor guard, the modified FRP plate and bottom spacer (rear) will work fine 4 Share this post Link to post Share on other sites
Sgt.Speirs 1253 Posted January 8, 2022 The upper bracket is modified. I have also to modify the front spacer. The new bracket was too thin to cut a thread in. Now the spacer is pressed in from the bottom side and locked vertical via the flange. Additional 2-component adhesive prevent that the spacer can rotate inside the bracket. The thread goes through the complete spacer. And the bracket mounted on the gear case. And the new rear bottom spacer is currently in printing. 2 Share this post Link to post Share on other sites
Sgt.Speirs 1253 Posted January 8, 2022 And the final bottom spacer for the rear... Next step is to modify the FRP plate to fit the motor guard. 3 Share this post Link to post Share on other sites
GTodd 1349 Posted January 9, 2022 This is AMAZING! I’ve got the stealth conversion that was offered a few years ago in my childhood Monster Racer. Once you have perfected this I’d like to purchase a sub chassis and associated parts to mount the trans if you are willing. As much as I love the stealth I don’t like using non Tamiya Parts on the MR. 1 Share this post Link to post Share on other sites
Sgt.Speirs 1253 Posted January 9, 2022 1 hour ago, GTodd said: As much as I love the stealth I don’t like using non Tamiya Parts on the MR. That was my goal/incentive...a alternative transmission with Tamiya only parts (except spacer/brackets). Maybe at the end of this conversion/mod there is a special TRF gear case with attachments for the King Cab/Hilux MR chassis available. And also the corresponding „sub chassis“ (FRP plate). We will see… 1 Share this post Link to post Share on other sites
Honza 936 Posted January 9, 2022 On 1/5/2022 at 3:33 PM, Sgt.Speirs said: go forward with the standard TRF201 ball differential. It's the same (should be the same) as the ball diff for the Super Avante (22025 - TD4 Ball Differential Set, as spare part this year/spring available). TD4 is designed to fit the TA06 gear diff, so its ball diff will be probably wider, too. Share this post Link to post Share on other sites
Sgt.Speirs 1253 Posted January 9, 2022 @Honza: I bought already the ball diff as separate components (same part numbers as in the Super Avante manual) and the ball diff fits into the TRF gear case. So I assume that the complete ball diff as spare part will be the same. EDIT: I bought for the ball diff the spare part numbers of the Super Avante and also the slipper clutch (TA-22031). They fit… Share this post Link to post Share on other sites
Collin 1956 Posted January 9, 2022 On 1/8/2022 at 3:30 PM, Sgt.Speirs said: I dont know which forces this mounts have to deal with but I dont think hey last long on a FDM printed part. 1 Share this post Link to post Share on other sites
Honza 936 Posted January 10, 2022 9 hours ago, Sgt.Speirs said: I bought already the ball diff as separate components (same part numbers as in the Super Avante manual) and the ball diff fits into the TRF gear case. Sorry, earlier I read that you bought the TRF diff. Looking in the manual, TD seems to have offset bearing on one of the diff outdrives, so it's quite interesting that it fits, but the gear diff doesn't. Anyway, great project Share this post Link to post Share on other sites