Gabriel82

iTrader: (8)

So I figured I'd write a quick review on the PSM Knuckles for the FC. I normally do grip driving with my NA FC. It seems that one of my knuckles could have been damaged so I decided to try something new.

At first glance
1) You cannot run the OEM rotor dust shield/backing plate on the PSM Knuckles
2) Ackerman is reduced significantly from the OEM knuckle.
3) The knuckle does come with built in roll center correction.

My impression with them at the track
My first two sessions took some time to get used to, the steering was super quick. I needed to figure out how much steering was necessary to get the car in the direction that I wanted. It took less effort than the OEM knuckle. Once I got used to how the car felt the steering was super precise and quick which I really enjoyed.


OEM vs PSM


Potential Fitment Issues
At full lock my tire would touch my side skirt. My wheel is 17x9.5+22 with 245/40/17. I just filed a little off my side skirt and the issue was gone. This only happened when I was reversing out of my driveway.


Roll Center Correction (CHECK YOUR CLEARANCE)
One thing I NEED to point out. If you have extended ball joints please be mindful of the excessive roll center correction you will have. I noticed I had a very close gap between the bottom of my ball joint bolt and my TE37. I drove the car around and it never made contact. It wasn't until I drove the car on the track and heavily loaded the wheels that the bolt on the bottom of the ball joint made contact. My recommendation is lift the car from one side. Load the opposite tires and go check clearance. You might have to file your ball joints depending depending on what you have or go back to OEM. Hope this never happens to anyone else.






Last Comments
I love the knuckles, I like how they made the front steering more agile and precise. Great bang for the buck at $400 + shipping & tax. OEM hubs fit with no issues. I wish I would have thought about loading the wheel to check my ball joint to wheel clearance. But you live and you learn. Hope this helps anyone out there with answering their questions or helping their curiosity. Hope to see more FCs at the track and not the garage!

DaBrkddy

Silly question here...

Why would one want less caster angle? Does the FC inherantly have too much? I have noticed a lack of front grip in tight, low speed turns at high steering angles. Is this the reason? (Assuming everything else is set correctly.)

Gabriel82

iTrader: (8)

No the original caster was just fine. From multiple alignment my mechanic mentioned there was probably a discrepancy between both struts, we noticed something was off when setting camber. I just wanted something new that wasn't 30 years old hence why I opted for the PSM knuckles. The reduction in caster wasn't significant for me to notice when driving.

Before Knuckles



After PSM Knuckles

mdq-fc3s

Awesome to hear the steering is like having a quick ratio steering rack (this is what I wanted in my car), I was worried that the Ackerman angle being alter would have a negative impact to grip racing, but no need to worry since you had a good experience with it (minus the rubbing of the wheels).

adrictt

Thanks for the review

Gabriel82

iTrader: (8)

Yup the rubbing of the wheel was just lack on knowledge/experience. I knew the ball joint was close but I didn't think the control arm would track low enough to have the bolt contact the wheel. It only happened on a pretty angled turn at Streets of Willow (the bowl). From what the rep at PSM mentioned he stated that the Ackerman is reduced but not set at zero.

Gabriel82

iTrader: (8)

You're welcome. I'll probably post a Youtube video about the suspension within the next month or two. Sometimes visuals help answer questions/curiosity.