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-   -   Recommendations for reducing driveline slop needed (https://www.ft86club.com/forums/showthread.php?t=92497)

mid_life_crisis 07-29-2015 11:16 AM

Recommendations for reducing driveline slop needed
 
I drive a slushbox, so some sloppiness when shifting is unavoidable. However, I'd like to reduce it some if possible, short of tearing into the transmission itself. What I'm wondering is which mods will help reduce the driveline slop when shifting while having the least effect on ride comfort when just cruising.
At this point I'm thinking one of those rear end braces looks like the way to go.
Anyone have any good ideas or comments?

drewbot 07-29-2015 11:18 AM

Look into the tranny mount and rear subframe bushings ie. go nuts and buy all the Whiteline catalog

There is very little slop for me after that

Freeman 07-29-2015 11:24 AM

Also, look into a one piece drive shaft.


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mid_life_crisis 07-29-2015 01:19 PM

Quote:

Originally Posted by drewbot (Post 2339027)
Look into the tranny mount and rear subframe bushings ie. go nuts and buy all the Whiteline catalog

There is very little slop for me after that

What did it do to ride comfort and, it just crossed my mind, vehicle noise? Everything is a compromise, but how much?

drewbot 07-29-2015 01:53 PM

Quote:

Originally Posted by mid_life_crisis (Post 2339203)
What did it do to ride comfort and, it just crossed my mind, vehicle noise? Everything is a compromise, but how much?

Noise:
Climbing up the RPM's the transmission emitts a "whine", mostly pronounced in 1st gear with low throttle. It's by no means VERY loud.

With the subframe, I don't think I experienced any noise increase.

Vibration/Comfort:
Shifts will feel firmer and that's what you wanted. So, the lack of slop will be more rough but feels great.

I might be confusing all the bushings I've done, but there is more road communication (slight vibration) in the steering wheel. You feel what the car is doing more. The increase in vibration is no more different than driving on two different road surfaces.

Bergen23 07-29-2015 02:04 PM

Quote:

Originally Posted by drewbot (Post 2339273)
Noise:
Climbing up the RPM's the transmission emitts a "whine", mostly pronounced in 1st gear with low throttle. It's by no means VERY loud.

With the subframe, I don't think I experienced any noise increase.

Vibration/Comfort:
Shifts will feel firmer and that's what you wanted. So, the lack of slop will be more rough but feels great.

I might be confusing all the bushings I've done, but there is more road communication (slight vibration) in the steering wheel. You feel what the car is doing more. The increase in vibration is no more different than driving on two different road surfaces.

Did you go nuts and buy everything? I've been considering some things, but the only bushing I can see myself buying in the near future is the PBM diff riser. That way I can go lower and have less of an angle on the CV and stuff

drewbot 07-29-2015 02:26 PM

@Bergen23

I have the following installed:

KDT926 Front Gearbox - positive shift kit bushing
KSR210 Front Steering - rack & pinion mount bushing
KDT922 Rear Crossmember - mount insert bushing
KDT925 Rear Differential - mount in cradle & support outrigger insert bushing

Bergen23 07-29-2015 03:00 PM

@drewbot Interesting. And you felt the difference? Or is it a bit of a placebo effect? I don't have much intent on tracking/autox very often due to always being on the road, but the diff riser bushing definitely has me interested. Did you do the install yourself?

drewbot 07-29-2015 03:24 PM

@Bergen23

The difference is that the car feels even more nimble and willing without being too "enthusiastic".

Whether or not it is shaving massive time on an AutoX course or time attack - I don't really know as I am no where near the limit of this car. All I know is that there is a subtle but very good difference in feel.

This was all done when I was bone stock ride height and tires though, so in your current setup I wonder if the changes would be masked by your coils and wheel/tire setup.

Cuchullain 07-29-2015 04:02 PM

I just have the "KDT925 Rear Differential - mount in cradle & support outrigger insert bushing" and I have a bit of whine, mostly when the car is coasting / engine braking, but it is not bad. Actually, the whine was there before, it just changed pitch and a small increase in volume after installing the kit.

The kit did definitely help tighten up the rear end. the kind of bouncing I would get if I were driving in heavy traffic is almost gone, and the ride feels better to boot.

Bergen23 07-29-2015 04:05 PM

Quote:

Originally Posted by drewbot (Post 2339441)
@Bergen23

The difference is that the car feels even more nimble and willing without being too "enthusiastic".

Whether or not it is shaving massive time on an AutoX course or time attack - I don't really know as I am no where near the limit of this car. All I know is that there is a subtle but very good difference in feel.

This was all done when I was bone stock ride height and tires though, so in your current setup I wonder if the changes would be masked by your coils and wheel/tire setup.

Like I said, not all that interested in going hog wild with everything, just on the fence about the diff riser. Also, given that I regularly drive to the cottage (about 2.5 hours) I don't know if I want to deal with added NVH, but the less wear and tear on my diff/axles, etc may be worth it.

stevesnj 07-29-2015 05:08 PM

Lube your U joints if they are greasable, dry U joint needle bearings are a common cause of vibration. Use exactly what grease is specified. Also make sure the balancing weight hasn't come off somehow. That usually doesn't happen but always good to check.

drewbot 07-29-2015 05:23 PM

Quote:

Originally Posted by Bergen23 (Post 2339509)
Like I said, not all that interested in going hog wild with everything, just on the fence about the diff riser. Also, given that I regularly drive to the cottage (about 2.5 hours) I don't know if I want to deal with added NVH, but the less wear and tear on my diff/axles, etc may be worth it.

The NVH isn't THAT bad IMHO. Since you are about that low life and single exit I don't think the NVH will be an issue for you.

Also, some of these pieces do require 4 sets of hands (at least for me), I got everything ready and unbolted only to find myself short spare hands. That may be partially because I was doing this with very little clearance between my face and the car

Bergen23 07-29-2015 05:50 PM

Quote:

Originally Posted by drewbot (Post 2339631)
.

Also, some of these pieces do require 4 sets of hands (at least for me), I got everything ready and unbolted only to find myself short spare hands. That may be partially because I was doing this with very little clearance between my face and the car

Reminds me of installing my toe arms. That SUCKED. Trying to maneuver a hammer back there to force the stock toe arms out was not a fun task


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