[JaxChris]

On top of springs I also have the fixed sway bars and fixed upper/lower trailing arms installed. The trailing arms were perfect for getting rid of wheel hop at stock power when doing launches and the sways keep the car much flatter in turns now.

My guess as to why the MRC cars ride higher is that I think the spring seat on these struts & shocks are actually a little higher. This just means MRC cars should definitely size up to 285/305 in 35/20 instead of 30/20 when doing wheels & tires. The little extra tire diameter will go well to fill the slightly increased ride height.

Once I figure out which wheels, I think this will look even better.

[SS 1LE]

Originally Posted by JaxChris

On top of springs I also have the fixed sway bars and fixed upper/lower trailing arms installed. The trailing arms were perfect for getting rid of wheel hop at stock power when doing launches and the sways keep the car much flatter in turns now.

My guess as to why the MRC cars ride higher is that I think the spring seat on these struts & shocks are actually a little higher. This just means MRC cars should definitely size up to 285/305 in 35/20 instead of 30/20 when doing wheels & tires. The little extra tire diameter will go well to fill the slightly increased ride height.

Once I figure out which wheels, I think this will look even better.

Remember the taller tires will also slightly (negatively) effect your gearing. The SS 1LE's come with MRC, tuned slightly different yes, but they have 285/30/20 and 305/30/20 tires.

[JaxChris]

In which way are you referring? I can't think of a negative impact from being slightly taller. In fact the tire diameter of 285/35/20 at load (27.9" shrinks to about 27.7") should match perfectly with my lowered 28" fender to floor height.

The diameter of 285/35 over 245/40 is only +0.2" (less than 1%). This means negligible speedo impact of actually going 110mph when it says 109mph. I wouldn't run 305/30 on the A8. The top speed per gear is impacted enough that you would add an extra shift to your 1/4 mile. Staying slightly taller avoids that.

Please don't read this post as opening an argument; I'm intrigued by your comment and want to learn where I might be overlooking a negative impact. We all learn from each other.

[crankaholic]

Originally Posted by JaxChris

In which way are you referring? I can't think of a negative impact from being slightly taller. In fact the tire diameter of 285/35/20 at load (27.9" shrinks to about 27.7") should match perfectly with my lowered 28" fender to floor height.

The diameter of 285/35 over 245/40 is only +0.2" (less than 1%). This means negligible speedo impact of actually going 110mph when it says 109mph. I wouldn't run 305/30 on the A8. The top speed per gear is impacted enough that you would add an extra shift to your 1/4 mile. Staying slightly taller avoids that.

Please don't read this post as opening an argument; I'm intrigued by your comment and want to learn where I might be overlooking a negative impact. We all learn from each other.

I think SS 1LE meant that a larger radius wheel will effectively change your final drive ratio... since wheel diameter to road surface can be looked at like another gear ratio.

Say you have a stock 275mm section tire with a 35 aspect ratio over a 20" wheel (dat metric and imperial mess doe ) that moves the car 7.22 feet with every revolution of the wheel; a 305/35R20 wheel will move the car 7.44 feet. Looking at this from a dyno perspective (assuming a single 36" roller), you changed your ratio from 2.41:1 to 2.48:1... not that insignificant.

[SS 1LE]

Originally Posted by crankaholic

I think SS 1LE meant that a larger radius wheel will effectively change your final drive ratio... since wheel diameter to road surface can be looked at like another gear ratio.

Say you have a stock 275mm section tire with a 35 aspect ratio over a 20" wheel (dat metric and imperial mess doe ) that moves the car 7.22 feet with every revolution of the wheel; a 305/35R20 wheel will move the car 7.44 feet. Looking at this from a dyno perspective (assuming a single 36" roller), you changed your ratio from 2.41:1 to 2.48:1... not that insignificant.

Yes, that was what I was getting at. It's not a big change, but a change none the less...

[Zap city]

Any negative ride quality increase with the lowering springs installed in your opinion?

[MakCamaro]

And back to resurrection! I installed the same kit. Very satisfied with the result.

[GTO_Gregory]

Originally Posted by Zap city

Any negative ride quality increase with the lowering springs installed in your opinion?

As long as you don’t have run flats, there is no negative increase in ride quality by lowering the car.

My ride quality improved. I installed .750-inch drop springs. The old tires were the 40 and 35 series Goodyear Run flats. I changed out the Goodyear Eagle F1 Asymmetric 3 Runonflat tires and they have very, very stiff side walls. I took them off the rim myself, so I know how stiff the sidewalls are. I now have 30 series Goodyear Eagle F1 Supercar 3 non-run flat tires and the ride is softer. The car has Magnetic Ride Control.

Oh, and I have HP Tuners, so I made the slight adjustment in tire diameter to keep the speedometer correct.

[Msquared]

As an about-to-be SS 1LE owner, I'm interested in this thread. RE tire diameter, I will add that taller tires are generally not good for cornering grip. First, they raise the entire car, which increases lateral weight transfer, which lowers overall grip (does the same for braking, too). Second, they will raise the Roll Center, which increases jacking. That means the overall ride height will increase more during cornering/braking than if the car were on shorter tires.