WheelNut

iTrader: (5)

After seeing this new option part for the S204 Impreza STI. There is on that goes in the trunk and one that goes on the front lower subframe. It is basically a super stiff damper that smooths out flex movements in the chassis of the car. Supposedly makes the car easier to drive and more stable.
http://us.st11.yimg.com/us.st.yimg.c..._1934_10084482

So I figured why not try this on my XB8? After all chassis flex is a tuning option that is often messed with and has a large effect on the way a car handles I think this may make a difference in the way the car feels. Many people run the XB8 with no rear chassis brace at all (Yannick for one) I think the car will be relatively safe on a normal track, for supercross tracks I'll add the plastic brace. Since the chassis is basically a big spring after all, but there is no damping at all for it, so any oscillations go unchecked. I doubt there is much going on in the way of spring back motion, you never know since after all you can't see that kind of detail while driving.

The damper is RC10GT shock body with a Savage shock shaft, #3 pistons and 30k oil (currently). From hand testing I've measured a full centimeter of travel from full compression to full extension. The shock doesnt really interfere with anything on the car besides the throttle link, which is easy enough to remedy. I will also try out some thicker oils as 30k seems a tad soft, mabye some 100k, or some #1 pistons w/30k oil.

I won't be able to test this setup until March 1st though, so it will be a while before I can see what it does.

It was quite easy to install this as well, just drilled a hole in the rear body mount (highest point, so the damper will receive maximum travel) and flipped the centre diff brace front to rear then used the hole for the fuel filter to mount the ball stud. I also weighed this setup, its about 20g heaveir than the stock aluminum brace w/screws.

Turbine_au

iTrader: (6)

Interesting idea, I'd be keen to see how it goes. Although, I dont really think you'll notice much difference. After all, the chassis braces (plastic or aluminium) act in a similar way to dampers, just much firmer. Fitting the damper like you have probably gives you a different setting between running a brace and not running one.

K.Copeland

iTrader: (96)

Cool idea, but install your engine and then flex the chassis. The clutchbell and bearings aren't going to last long.

WheelNut

iTrader: (5)

I am running the one piece engine mount which stiffens the clutch/spur region. I realize I as treading on thin ice for durability with this setup though. I will be adding the plastic brace more than likely to aviod bending the chassis when I test it out in March.

jfc_tech

iTrader: (4)

Its in the Blog! ... u deserve it WheelNut. pls comment or request to take it out if you wish so

mfishel

I think you need to add some rake to that damper. Otherwise you may just be locking that shaft in the body.

sosidge

Yokomo had a few electric cars with a sprung top deck. Invariably it got removed in later versions.

In terms of controlling chassis flex I think having a few alternative braces of different thicknesses would do a more consistent job.

jfc_tech

iTrader: (4)

interesting input there. hmmm. more room for improvise there.

DiscoDan

I think that if the travel of the dampener is limited correctly in both directions it could be a usefull tuning device. Of course there is alot of setup trial and error to do with something like this... I hope to see how it works. Obviously the plus is that it was accomplished without hacking the buggy, and can be used in conjunction with plastic or alum. brace.

K.Copeland

iTrader: (96)

If your running the 1 piece engine mount, and do as DiscoDan says, and limit the travel of the damper ( dampen refers to moisture doesn't it?), use a really thick shock fluid and spring, you'd be golden. Just like a 1/12 chassis.

WheelNut

iTrader: (5)

The entire car (chassis, motor, radio tray everything) acts as the spring for this damper, a very stiff sping, which is why I'm using such thick oil. I'm definately not going to try and limit the travel of the damper as it woiuld probably break it somewhere if crashed hard enough. I may try mounting the damper at an angle as opposed to horizontal, because yeah I suppose with such a long shaft there could be a problem encountered with the shaft jacking the shock and locking it with all the friction (hard to use the right words). If it was on an angle it would be in line with the plane of movement the rear shock tower will expirence. I'll have to see if there is space or not though first.

It is basically like a 1/12 car yeah, but with a really really stiff T-plate, and obviously no solid axle.

jfc_tech

iTrader: (4)

u got a point there..
keep us updated and the blog too. we need u
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