Lexus F-Sport Underbody Chassis Brace on IS-F
02-14-19, 02:45 PM
#1
Lexus F-Sport Underbody Chassis Brace on IS-F
There was a thread some years back about someone putting this on their IS-F but the pictures didn't work and it seems they did some fabrication to keep the aero panels on, I wanted to find out for myself so:
I had this brace on my IS250 6MT and unfortunately sold it with the car. When I did have the 250, this was arguably one of my favorite mods for it since it significantly tightened up the rear. I know this for a fact since I have to go sideways into my driveway and 3-wheel sometimes. Without the brace the body would creak and I could tell the suspension was under load. With the brace, no more creaks and the wheel lifts quickly and the suspension compresses smoother.
When driving with it, one thing I noticed is the rear "follows" much faster. You can tell where the rear wheels are much easier and the car feels more connected to you.
Believe it or not the aero panels still go on, you just lose 3 small plastic screw clips on each panel but, there are still 4 major screw / clips that are used to keep them on.
The panels require some chopping (I have more to do) to get them flat but nothing crazy.
I was able to pick the brace up off someone who didn't know what they had. Despite the rough shape, it was nothing a quick paint job couldn't fix. I went with flat black to keep it more subtle. If I refinish it in the future I'll probably powder coat it orange.
Interestingly enough it was a net gain of only 6 lbs. despite being a much more intricate piece than the 3 stamped steel pieces it replaces.
Part Number: PTR0253081
Before:
After:
Decently heavy for 3 small steel pieces.
I had this brace on my IS250 6MT and unfortunately sold it with the car. When I did have the 250, this was arguably one of my favorite mods for it since it significantly tightened up the rear. I know this for a fact since I have to go sideways into my driveway and 3-wheel sometimes. Without the brace the body would creak and I could tell the suspension was under load. With the brace, no more creaks and the wheel lifts quickly and the suspension compresses smoother.
When driving with it, one thing I noticed is the rear "follows" much faster. You can tell where the rear wheels are much easier and the car feels more connected to you.
Believe it or not the aero panels still go on, you just lose 3 small plastic screw clips on each panel but, there are still 4 major screw / clips that are used to keep them on.
The panels require some chopping (I have more to do) to get them flat but nothing crazy.
I was able to pick the brace up off someone who didn't know what they had. Despite the rough shape, it was nothing a quick paint job couldn't fix. I went with flat black to keep it more subtle. If I refinish it in the future I'll probably powder coat it orange.
Interestingly enough it was a net gain of only 6 lbs. despite being a much more intricate piece than the 3 stamped steel pieces it replaces.
Part Number: PTR0253081
Before:
After:
Decently heavy for 3 small steel pieces.
Last edited by JohnMorgan; 02-19-19 at 02:21 PM. Reason: PN
The following 4 users liked this post by JohnMorgan:
02-21-19, 03:14 PM
#11
thanks. Just ordered one and looking forward to installing it.
02-21-19, 04:45 PM
#12
Keep in mind you are going to have to do some trimming on the aero panels if you want them to go back on and be as flat as they can. I'm going to my buddies shop tonight to get underneath the car and do the final trimming on the panels. I'll post pics when I'm done.
02-21-19, 07:13 PM
#13
that shouldnt be a problem. Reminds me of the x brace mod on my e36 m3 which made a noticeable difference in firming up the chasis. Thanks for sharing this!
02-21-19, 07:34 PM
#14
Poly bushings are by Grimspeed! they're the 12mm 2 position ones, I wasn't sure what to get so this made it easy. Exhaust doesn't move at all (can't say I'm a fan of the red though).
02-21-19, 09:44 PM
#15
Instructor
Couldn't agree with you more. You don't realize how lethargic the chassis is until you start tightening it up. I will say with Lexus' philosophy on keeping it a luxury sports car instead of a full on sports saloon was done well to the T in stock form.
Poly bushings are by Grimspeed! they're the 12mm 2 position ones, I wasn't sure what to get so this made it easy. Exhaust doesn't move at all (can't say I'm a fan of the red though).
Poly bushings are by Grimspeed! they're the 12mm 2 position ones, I wasn't sure what to get so this made it easy. Exhaust doesn't move at all (can't say I'm a fan of the red though).