Weapon F

Was at my local dealership few days ago checking out the new RC F they let me go over it pretty thoroughly pretty cool dealership. Hung out with service manager and mastertape as we check the car. So my question do you guys think the upper strut mount brace will fit on the ISF? that most likely the engine cover would have to be modified to make it fit that not to big of deal to me, it's width and angle of the brace would they fit over our current strut mounts locations. And even if the angle and length are off do you think it would be possible just to have them cut and rewelded back into position to make it fit. Here are some pic's

4TehNguyen

iTrader: (1)

RC uses a GS front end, doubt the dimensions are the same. Im sure it can be done with fabrication, but I doubt it will be just a drop in

Weapon F

Thanks 4tehNguyen was thinking same thing with having to do a little fabrication to make it fit.

ISFpat

iTrader: (10)

Why not have another company weld one up for you? Its a different chassis and thats just a generic upper strut brace.. taking it from an RCF then modding it will cost more than having an outside party fabbing one up for you.

Also how do you know that the RCF brace bolt locations are the same for the ISF? (if it even has one)

How do you know this is beneficial for the ISF chassis and its not just a pseudo effect? (doesn't even come with the ISF or even an option)

I8ABMR

dont know a single person who has ever mounted one ( after market ) who felt any change in handling. Maybe on a track and even then it would be splitting split hairs

Bigcloud

I noticed a change in turn in with my GTSpec brace. I'm also in the process of putting on on my Race Car as it does affect handling and stiffens up the chassis.

lobuxracer

iTrader: (2)

Your race car has struts. The IS F does not. It won't make nearly the difference it does on your strut suspension.

Reaper21

iTrader: (1)

Care to elaborate on this? (for learning purposes, not questioning you).

flowrider

iTrader: (9)

^^^^The Lexus IS line uses a Double Wishbone Type suspension with Coil-Over Shock Absorbers. Lexus does not use McPherson Struts in the IS Series. My last car, an Infiniti G35 used Struts, and the Strut Tower Brace I added made a difference I could feel. Folks who have added a Shock Tower Brace to the ISF have generally reported no increase in rigidity.

My Wife's ES350, had struts, and Lexus put an STB in that car. It still handled like crap, but it had Strut Tower brace.

The attached, Lexus's description, describes the ISF front suspension better than I can.

Lou

Gearbangin

iTrader: (7)

Forget that what about that engine cover! I guess you'd have to move several things too.

lobuxracer

iTrader: (2)

Just do some vector analysis of where the forces are being loaded into the chassis, and it should be pretty obvious why a double wishbone is preferred for a more dimensionally stable chassis.

If you look at Lou's picture above, notice the spring and shock only have a tiny amount of side loading. All the suspension forces are vertical with the spring and shock assembly. The upper wishbone takes care of all the side loading being fed into the chassis, and the mount points are much lower and closer to the front subframe for enhanced rigidity compared to a strut suspension.

A strut feeds all the lateral force into the hat on the shock because the strut replaces the upper wishbone. The strut is responsible for a whole lot of duties in a MacPherson suspension and worst of all, it feeds the lateral forces into the highest point on the front of the chassis giving it the greatest leverage at the weakest point. All of this conspires to make extracting truly high performance from a strut very difficult and even when done right, the service life is inherently shorter than a double wishbone because the strut body, piston, top bearing, and shaft all need to fit very tightly to prevent the wheel alignment from changing as a result of flex under load.

At the root of this all, keep in mind, the standard units for measuring dynamic suspension loads is tons.

Jowett

It's fairly easy for someone with a little fab skill to find out if things are moving and whether or not a brace could be beneficial. A simple telescoping "tube inside a tube" can be run either between the upper mounts, or the mounts and firewall. Any movement will be easy to measure as the tubes slide in and out.