Individual Racing Parts (IRP) V3 Short Shifter Rattle Thread

[grumpysnapper]

Originally Posted by Ruben_86_

If you manage to solve that vibration, it will surely end up appearing somewhere else

Yes, the root cause is the shift shaft insided the gearbox rear casing...but you can minimise its effects to a very large extent.

[NoHaveMSG]

Originally Posted by grumpysnapper

The rattle is actually internal vibrations transferred from the shift shaft just inside the gearbox then along the rod up into the shifter mechanism.

I took video of this a while back wondering if it was contributing.

https://www.youtube.com/shorts/5ZN0nQEFmlc

[grumpysnapper]

Originally Posted by NoHaveMSG

I took video of this a while back wondering if it was contributing.

https://www.youtube.com/shorts/5ZN0nQEFmlc

Yeah, thats the beast.... its annoying.... there is a very slight "play" somewhere internally with the rod in the rear housing, enough to transmit vibrations back through the shaft. Unfortunately the bush that the rod passes out through doesn't provide enough of a dampening effect.

I've been running my "hack" now for about a year, and it's held up really well...even surviving the carbon prop shaft self destructing directly underneath it.

Those harmonics affect the different shifters in varying ways.

Initially I also thought that there might be vibrations caused by the solid mounting of the exhaust to the gearbox. But I built some rubber mounts to eliminate that prospect.... and nothing changed.

[Swolzee]

Originally Posted by grumpysnapper

The rattle is actually internal vibrations transferred from the shift shaft just inside the gearbox then along the rod up into the shifter mechanism.

The trick is to try and dampen the rod mechanism as it exits the upper rear casing area, and then dampen the whole shifter arm.

I created a sort of "V" shaped bush that the shifting rod sits/slides in, wedged, on top of the large ring where the prop shaft enters the gearbox.
I use a very large zip tie that creates a small amount of downward pressure to force the rod against the "V" of the bushing.

That takes care of the most obnoxious rattle, but you still need to do some work above the tunnel, inside the car.

I simply take lots (lots!) of fairly dense insulation foam (the sort of black foam you wrap around a roll cage for example), cut it into smallish strips, roll them tight.
Then you go to town and pack/squeeze/push them into the entire cavity around the stick mechanism...so that it sort of fully/firmly encases the mechanism, as high as you can go.

Of course make sure all linkages, and bolts on the shifter are as tight as possible (I use locktite blue)

Its painful, but this removes about %90 of the rattle.

I'd love to see some pics of all this. Especially the bushing and how you have it installed.

Are any of you running stiffer diff bushings?
I'm thinking about going back to my OEM bushings to see how much that helps.

[Ruben_86_]

Originally Posted by Swolzee

I'd love to see some pics of all this. Especially the bushing and how you have it installed.

Are any of you running stiffer diff bushings?
I'm thinking about going back to my OEM bushings to see how much that helps.

I have installed and uninstalled the differential bushings 2 times to do tests, if it improves the throttle reaction, but for me it does not compensate for use on the road

The transmission insert seemed completely unnecessary

The subframe inserts do seem fundamental and have no inconvenience.

[grumpysnapper]

Originally Posted by Swolzee

I'd love to see some pics of all this. Especially the bushing and how you have it installed.

Are any of you running stiffer diff bushings?
I'm thinking about going back to my OEM bushings to see how much that helps.

Next time I'm under the car I'll take some pics.

In my experience OEM bushes or stiffer bushes have made no effective difference.

In the same way that trying to isolate the whole shifter mechanism (from direct contact with the transmission tunnel) with rubber bushes, which I have also tried in the past, made no real improvement.

The vibrations/resonance are all internal to the transmission rear housing, and then transferred directly out along the selection shaft.

[Swolzee]

Originally Posted by grumpysnapper

Next time I'm under the car I'll take some pics.

In my experience OEM bushes or stiffer bushes have made no effective difference.

In the same way that trying to isolate the whole shifter mechanism (from direct contact with the transmission tunnel) with rubber bushes, which I have also tried in the past, made no real improvement.

The vibrations/resonance are all internal to the transmission rear housing, and then transferred directly out along the selection shaft.

I'd really appreciate this. I need to develop a solution for my sanity.

[Texas2016Frs]

My shifter rattled so loud that it was audible when playing music loudly.

I almost entirely eliminated the rattle; however, it still rattles above 4700 RPM but not bad at all.

I put a slightly thicker Oring in between the shifter bushings and added two thin neoprene washers. I put one on against the linkage arm and one outside of the supplied nylon washer. This REALLY tightens up the shaft. It is a bear to get it on there. But once I did it almost completely eliminated my rattle.

If you are finding that depressing the button completely reduces your rattle this likely wont do much for you. It worked wonders for me.

[rice_classic]

If anyone needs a V3 IRP shifter, lmk.

I’d rather it go to someone here vs some low balling clown from offer up.