S550 Mustang IRS Bushings Before and After by Full Tilt Boogie Racing 

I just got a new Mustang and I'm just seeing this. I agree best camera work ever. This guy deserves an Oscar for Best Picture. 👍🏾👍🏾👍🏾 It looks like all you need are the bushings. The braces appear to be not necessary. Seems like a small amount of flex would help in hooking up when the car squats off the line, but I'm not an expert. I will put those in before deciding on braces or not👍🏾👍🏾👍🏾

Sounds awful. Exactly what I need to know before installing on my 15 gt pp daily driver. Did it improve handling and steering feel/directness?

GR1MREAPER, I was extremely impressed with just the rear subframe connectors on my '18. Front is next.

Agreed. This stuff is great for the guys on the track but not fir daily driving. I bought the BMR level 2 cradle lockout kit also and lowering springs. (Not installed yet)

Thx. Excellent advice. Will just put fresh OEM diff bushings with bmr sub lockouts.

@@jonasbaine3538 use oem bushings. Or it will drive you out of the car with the vibration and rear end noise.

@@xGR1MxREAPERx so don’t use bmr lockouts for subframe or you’re saying use OEM diff bushings with bmr sub lockouts ? Trying to fix wheelhop and improve handling feel

Bryant, I can't comment on BMR but we have been specializing in the mustang IRS since the 99 cobra. We've spent countless hours on this new S550 IRS learning the geometry. We do not rush to be the first with parts available. We do extensive R&D on all of our products before we put anything out on the market. All of our parts are American made with the largest most heavily dudy bearings and bushings we can fit in a particular location for strength and durability. On the street and track, our parts have completely transformed the car to be more capable and predictable.

Yes for the subframe bushings and no for the others.

We had absolutely zero added NVH with the addition of any of the IRS components until the differential bushing inserts were installed. Those did add NVH.

John Bergeron, Actually the ride felt better than stock. No more sloppiness and the car felt more predictable. The only bushings that added any NVH were the diff bushing inserts, and these are really only needed if planning on drag racing.

whats better these or just the braces or both ?

Just go too there website.... Full tilt boogie racing. I got there stuff for my 2001 IRS. From the looks of it the S550 chassis has more movement than the IRS in the Sn95's LOL.

Any info you would be looking for can be found here: fulltiltboogieracing.com or you can email us any time with your questions. Sincerely, The FTBR Team

S550 lower control arm spherical bearing assembly Full Tilt Boogie Racing part number FT 552

Actually the bouncing and wheel hop is what causes the axles and other IRS components to break. All the factory rubber was designed to do was absorb NVH. It has been proven if you want a reliable IRS that will perform well on both the street and track, the rubber needs to be replace with a less compliant material.

James Sarno but the NVH will be hell while daily driving?

That would be the lower control arm bushing. FT 552 and can be found here www.fulltiltboogieracing.com/2015_S550_Suspension_Parts_and_Tools.htm

We didn't like the brace idea and felt like it was just a band-aid. We use replacement bushings because it solidly holds the subframe in any condition or HP level.

what about bushings? .. I have the braces installed and am looking to go step further ...should I do diff inserts or bushings?

These parts are available at Full Tilt Boogie Racing. fulltiltboogieracing.com

+James Sarno thanks

Yes because more power is getting to the ground. Wider, stickier tires will help remedy this. But then will probably have to upgrade the rear axles.

jodl73 more power isn't getting to the ground lol. It just stiffens the crap out of the suspension so instead of wheel hop the tires just spin.

Dylan, The wheels spun before the bushing but had wheel hop. Wheel hop is a killer on suspension and drivetrain. Traction can be fix with the right tires and tire pressure.

+Dylan Larson When the wheel hops, the tire is intermittently losing contact with the ground. Which is why you get that stutter slid. When you stiffen the suspension the skid is more consistent. The downside is better tires are needed. Also stiffening the suspension prevents the violent movements on the suspension.

jodl73 I agree with what you're saying but after the suspension have been stiffened THAT much to where there's absolutely no play in the bushings it becomes a disadvantage. Sure you can throw on some 315s and do better but optimally you want a little bit of play.

Actually you are sadly mistaken because once the rubber bushings were removed in the control arms and articulating suspension components, these pieces were no longer bound up in non articulating rubber bushings. The new components are spherical bearings and Delrin bushings which allows the suspension to articulate much more freely and in turn IMPROVED the ride.

How much did you spend on all those bushings?

Less thank $2k.

I added these bushings and the car just felt like crap. Put the stock ones back. It really does remove wheel hop with the rest of other suspension mods, but what I found is that the car just feels too stiff and you can feel almost every little piece of rock on the streets. If you daily drive most of the time and only roll race every once in a while, don't bother with all this stuff. If you have serious power and race many times at the track, then yes, this will be needed.

My Cobra rode so much better/smoother with the new FTBR bushings.