He told me it was around 7.7 degrees if that makes sense, and it should be put at about 8.5, no sheet he didnt print out cause he didnt realign

 

Well it would be good to know if the other side was on the opposite end of the scale as I would suspect subframe shift. Any other symptoms while driving, noise etc? Take a shot of the rear bushing and see if its biased.
Mike

 

No other symptoms or nothing wrong, car was going dawm straight with old conti dw, changed tires for 275/255 combo, put.in an alignment and there we are, ill take some pics of front bushing later, but he told me both side where about 7.7, he told me those things can happen when you change tire size, strange cause I did with my last cars with little effect on driveability

 

Ok tire size is 245/35 front and 275/30 back, took pics of.front bushing, sorry can't lift the car I'm not at the shop,

 

It just gets me that they can't align because of a little tire upsized like that, I've put 245 in the back of my previous bmw that was fitted with 185 stock size, should I take an appointment at dealership to do it even if the car is within spec

 

There is something else going on here. The tire sizes you have are not far enough off the OEM diameters to cause this large a change in caster, and if anything, the rears are smaller, so one would expect slightly MORE caster. Are you lowered with springs or adjustable shocks? Did you ensure the tire pressures are correct?

I am running a very similar setup and did not have any caster issues at all with mine.

 

Nop, car is completely stock except for that, pressure 36 all around, I think im gonna try at a raceshop or dealer for another alignment, I'll keep you guys informed, tanx

 

Check your front shocks for oil leakage. If the shocks are in bad shape, they will let the front end drop - how much depends on how bad the shocks are - and that might be enough to see this kind of caster change.

 

I tried these numbers and my car was pulling to the right. Drove it that way for a week and went back for a realignment. Since I told them the specs they charged me again for the second alignment.

As soon as the tech realigned everything to again the car tracked straight and the steering feel even got a little firmer . Took 2 test drives with the tech to make sure the car tracked straight . Always my luck when I screw with my cars. I know all this is reaching a compromise but considering I do a lot of track days and my tires will never last more than 8-10k miles I decided its no longer a priority to stretch what is already going to burn out much faster. Glad I have the USRS and I am ready to kill some tires at the track LOL

Lobux surprised you have not replaced your LCA yet.

 

Toe won't make the car pull right or left. Your tech didn't do a good job.

I have them and they are getting installed. I just decided to take off the condom and do both front and rear at the same time.

 

Nice. Let me know if you need a hand.

 

Bushings are in. Both front LCA bushings, and the differential bushings are installed along with the OS Giken LSD. The steering feels totally different, more direct and instantaneous. Braking is dramatically better, and wheel hop is eliminated. I was able to skate the back end under acceleration in the wet without VDIM jumping in and spoiling the fun. Very impressive results. Big props to Mike at Figs for getting everything I needed and helping out with some install questions. I am not kidding when I say it does not feel like the same car. NVH is subjectively unchanged - I am on a 900 mile road trip home right now over some really bad Interstate in Illinois and it feels just as harsh as it did when I drove up from Atlanta.

 

those rear diff bushings sound interesting. just drove from chicago to davenport today and roads here are horrible. glad the F is at home sleeping.

 

Glad to hear you're liking the new upgrades to your F. You are correct that the changes you did make the Lexus feel like a different car. The differential bushings definitely help with increasing stability with the rear axle.

Hopefully you'll consider getting the revised IS-F Steering ECU to complement the steering feel improvements you're noticing with the FIGS LCA bushings.

 

Was installing the differential bushings a difficult job?