- Alexander Hagberg - Tech Tips - Body Mounting Positions -

Index:

  • PROTOform LTC-R

  • Xtreme Aerodynamics Brutale
  • Xtreme Aerodynamics Twister


    • PROTOform LTC-R
    I get asked this a lot about body mounting positions, and below I will try to explain how the position of the body will affect the handling of the car. The body in use here is the PROTOform LTC-R, which is by far the most commonly used shell for TC racing around the world today. It works very well for both carpet and asphalt surfaces - you can't go wrong with an LTC!

    As can be seen in the first picture, I am measuring the distance from the lower edge of the frontshield, to the center of the front body post hole. This is my reference for measuring the mounting position of the body. In the first picture, the distance measures 71mm, which is my basic position for racing on asphalt. This has the body sitting quite far forward, to get the most possible front downforce (increased turn in, and an overall more aggressive feel).


    For carpet, when a more mild steering feel is desired, I usually mount the body with a distance of 74-75mm. This will make the car roll more over the rear, and it won't be as twitchy initially. The car will also be more stable off power. This is important for carpet as that extra steering usually isn't needed, but a stable rear definitely is.



    The next two pictures shows the way that I measure the height of the XRAY adjustable body mounts. This nice option makes it much easier to fine tune the height of the body. (Part no. 301351-O).


    I have the front mount pinned through the 7th hole, counted from the bottom. And the 4th hole in the rear. The body mounts are set at 10.60mm both front and rear. The front may be lowered by 0.5mm or even more on asphalt, to try and generate more steering, as the lowered front body will give you more front grip. Be careful when running on bumpy or banked tracks though as the front lip of the body may start to drag, which will affect the cornering negatively. Have in mind that when the body is mounted more forward, you normally can't lower it as much in front as if it was in a more rearward position - this is due to the body posts sitting in the curved section of the front hood. Body mounted more forward = the body automatically becomes lower in front.

    I cut the front lip of the LTC-R quite low, leaving only 2.5-3mm. This allows you to run the front of the body lower, without having problems with dragging.

    I hope all of this proved helpful.

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    Xtreme Aerodynamics Twister

    I often get asked how I mount the Xtreme Aerodynamics Twister body. It’s no secret that this has become the most widely used body on the TC market over the last few months. A lot of people also asked me about the difference in feeling between the Twister and the ZooRacing DBX. To me, the Twister feels initially more aggressive, whereas the DBX tends to rotate smoother, and arcs the corner with a rounder feel. I hope this description makes sense!

    Furthermore - using the Twister over the DBX has proven advantageous at ETS events, because the 0.75mm version is closer to the weight limit used at those events (85g).

    Anyhow – onto the mounting of the Twister. After extensive testing, we’ve found that the optimal mounting position for carpet is 69mm distance between the center of the front bodypost, to the lower edge of the front windshield. For asphalt, we recommend 66-67mm distance, to get a more aggressive feel, with more turn-in.

    I’ve attached a picture of my front and rear bodyposts, to give you an idea of the height where I mount it at. I cut away around half of the front splitter, and I measure 8mm clearance to the ground when the car sits on my pit board, ready to run. The clearance on the sides should be 9mm or more. For racing on CRC black carpet, you need to add 2mm clearance to both these measurements, as the body tends to drag a lot more on black carpet!

    Wing wise – I recommend the 0.75mm wing that comes supplied with the shell. If you’re using a 0.5mm shell, I can recommend the optional 0.75mm wing set (MTRW1/10EPM-CUT). For stock racing, a hard wing isn't necessary.

    I mount the wing so that the front edge of the wing is in line with the wing mounts on the body (see picture).

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    Xtreme Aerodynamics Brutale

    I’ve received plenty of questions about my thoughts on the new Brutale bodyshell from Xtreme Aerodynamics.

    I’ve been testing this bodyshell recently together with my team mate Bruno Coelho. The body is fast! It feels very free in high speed corners, and turns well in 180 deg corners as well. The feeling is very different to that of the Twister/Speciale. At first, it can be difficult to get used to. But the body has more downforce than those bodyshells. The only negative that I’ve found so far is that the front end doesn’t feel quite as precise/direct as to that of the Twister. But it may also be a question of habit.

    The best mounting distance which I’ve found so far for asphalt is 69mm. For carpet, I recommend the standard 2mm split (2mm further back for carpet racing) at 71mm.

    The height of the body is different to that of the Twister/Speciale. The front mount needs to come down one hole (4mm) on the post. I use the 6th hole in front and the 5th hole in rear (with the kit T4'21 rear shock tower). Keep in mind that the rear hole has to come up 1 step if you are using the optional Low ULP towers.

    I have experimented with the wing position as well, and found 5mm further back to be the best starting point. If you desire more front grip, simply move the wing forward by 2-3mm. As for the bodyshell thickness, for large outdoor tracks, beware of the 0.5mm thickness, since it can come across as “flimsy”, which can cause the bodyshell to deform too much in high speed corners. In that case, try the 0.6 or even 0.7mm thickness. For any other condition, I recommend the 0.5mm version, for the best possible performance.

    Regarding the distances for mounting the body with horizontal posts on the T4’20 or 21, please refer to my guide from last September. I’ve modified my posts to have slots in them (see my tech tip post where I instruct on how to do this). You can use the same measurements as for the Twister/Speciale, since the rear part of the body is the same between those 3 bodies.

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    I've received many questions about the brand new Mach1 bodyshell from Xtreme Aerodynamics! Here's how I mounted it on my XRAY X4!

    64mm distance from the lower edge of the windshield to the center of the front bodypost, which is considered forward (the way we mount most bodyshells). The bodypost hole heights are with an EFRA legal roof height in mind. Please use horizontal posts if you're racing in spec classes, or on smaller tracks with good grip. Vertical posts are recommended for modified racing on bigger tracks and/or with lower grip. I recommend the Manzo46 bodyshell stiffeners, especially for modified classes, for more high speed stability (see picture).

    The UL version is recommended for indoor, and for spec classes outdoors. For modified classes, especially for big tracks, I recommend the L version.

    The Mach1 can be compared to the ZooRacing Wolverine in terms of handling! A little less drag, very good top speed, but less downforce than the Twister or Speciale from Xtreme Aerodynamics.

    As for the angled rear wing, the supplied 3° wing has less downforce than the optional 4° wing!

    Source:

    A. Hagberg