Driveline Slack

[drewcrolwey]

A few months ago I installed some powerflex race motor mount inserts in my 2016 Fiesta ST, (my car is approaching 50,000 miles and has a mountune rear motor mount), I had them in there for a few weeks but I decided the drone and vibration increase was a little extreme for my daily driver so I took them out. Ever since, the car had not felt as good as it did before the powerflex install. The driveline just felt like it had a lot of play in it and was really hard to get a smooth shift. If I was off the throttle and then lightly applied throttle during normal driving, I could feel the driveline take up slack before the car accelerated.
A friend of mine has a 2018 Fiesta ST with 10,000 miles on it that is 100% stock and shifted way better. I notice my engine sat significantly higher in my car than it did in his so I lowered the engine a bit. This helped a lot but I'm still feeling that slack when I'm off throttle and get back on maintenance throttle very gently.
My question is: Is this just because my car has five times the miles of my friends car and is just worn in or is there something wrong with the car I should have addressed?
All the motor mounts are tightened down to the OEM torque specs.

 

[Rocketst]

I've actually noticed this as well and haven't figured out why. Before I ripped the car apart everything was tight and felt solid but I've put a new motor in, an lsd swap and 4.3 final gear and I notice the trans sounds like it's catching momentarily after throttle it's a weird feeling and doesn't always happen but could also be compared to "slack" in the drivetrain. Let me know if you figure anything out. I also have the powerflexs and don't plan on taking them off.

Sent from my moto z4 using Tapatalk

 

[PhoenixM3]

I just received aluminum shifter shims from Whoosh. I’ll install today and report back.

 

[Ricky ST]

I just received aluminum shifter shims from Whoosh. I’ll install today and report back.

And did you come and report back to us? Lol good to know basis

 

[PhoenixM3]

And did you come and report back to us? Lol good to know basis

Well, technically, I stated I’d install today......but guilty of not reporting back.... My thoughts on the shims are that it does improve shifter feel a little bit, but it’s not as dramatic as I’d hoped. I dont ‘speed shift’ especially under full throttle, but I certainly don’t baby the car. I really making improvements to the car, and I’m sure that the shims are a notable improvement, but don’t think the shifter feel and accuracy has reached “Miata” level.

 

[MagnetiseST]

Well, technically, I stated I’d install today......but guilty of not reporting back.... My thoughts on the shims are that it does improve shifter feel a little bit, but it’s not as dramatic as I’d hoped. I dont ‘speed shift’ especially under full throttle, but I certainly don’t baby the car. I really making improvements to the car, and I’m sure that the shims are a notable improvement, but don’t think the shifter feel and accuracy has reached “Miata” level.

Get a Coolerworx shifter, you'll change your mind

 

[PhoenixM3]

Get a Coolerworx shifter, you'll change your mind

I need other things first. Id really like an LSD, lighter wheels, different exhaust, the list goes on....