I wanted to answer a question nobody is asking, what happens when you mix sports shocks with stock replacement shocks, in this case, Bilstein vs KYB, KYB Excel-G on the front with Bilstein B8 on the rear.
The Questions
- What does it feel like?
- Is it dangerous?
- Is it better?
- Is it worse?
- Can you tell the difference?
The Answers
Can you tell the difference?
Absolutely!
When I am driving at normal pace the ride (from the front) is noticeable comfier. And that’s about all the difference there is at low speeds.
However when the speed rises I noticed at lot of things.
First of all, in hard cornering it’s obvious that there is a mis-match in the damper rates front to rear. The front and the rear are not working in harmony. It gives a disjointed driving experience.
Is it dangerous?
If you try to go down the same piece of road at the speed with the original equipment front shocks vs the sport shocks in the rear, yes it dangerous because the cornering performance is lower. There is huge understeer on corner entry and the front of the car takes a while to settle.
I’d say it takes around 30% of a corner before you can be confident that the car is tracking on your chosen line.
Is it better?
For low speeds, ride comfort is better, no question, so that’s an improvement.
Is it worse?
At higher speeds I could not find a single aspect that is better. Grip is lower, level of confidence is lower and there is understeer. All negative.
The car also takes longer to settle over undulations.
To cap it all I am getting tyre squeal from the inside front tyre which I never had before, ever, on the road.
In short, for fast driving, everything is worse.
The Summary
In my opinion, Bilstein vs KYB, Sport vs Stock dampers, there is absolutely no reason to run shocks with such different rates front and rear. I can run front dampers a little softer on the front with coilovers and that can help front end grip. But I think the difference in firmness between stock shocks and sport shocks is simply too much.
It would be better to run either a full set of Excel-G front and rear, than running Bilstein B8 on the rear and Excel-G on the front. Sure there will probably be more roll with Excel-G but at least the front and rear of the car will be acting in a similar way, at least there will be some balance to the chassis.
For the best performance, using Bilstein B8 front and rear is the ultimate choice. Even better than coilovers in my opinion because combined with H&R/Eibach lowering springs, the suspension has the compliance to deal with bumpy roads and the stability to make the use of smooth roads.
Bilstein vs KYB, Wrap-Up
Before fitting the Excel-G, I thought there would be a noticeable difference in performance but I completely underestimated how big the difference would be, it’s simply huge.
There is no comparison.
I had ten times the confidence to push on with the B8s all round compared to the Excel-G on the front, B8 rear.
As a side note, I also get the feeling that front tyre life is also going to be much less using a softer front shock because it feels like the tyres are washing across the surface of the road on corner entry. With the sport damper in the front and rear, the front would carve into the turn as soon as you turned the steering wheel.
There is no reason to mix dampers, the dampers have been designed to work together, if you want the best performance, and you only need to change the shocks at the front or the rear, replace like with like. If you want to upgrade from sport to stock, or go from stock to sport, change all four dampers