1990 Mitsubishi Galant GLS rear coilovers too soft after 100miles.

[vig444]

Hello everyone, I need help following the installation of D2 street coilovers.

The first ride was incredible in terms of handling, almost no more bodyroll, the body was completely stable and on rails when cornering. After doing a second ride of just under 100 miles, I noticed that I started to have a lot more body roll, and bounce in the rear.

After taking the time to inspect everything I noticed that the rear units are much more flexible than the fronts.

Here is the hardness of the springs 7.5kilos at the front and 7.2kilos at the rear. The preload is correctly done and the tightening as well.

So I decided to add a little preload at the rear, it's a little better however I still have as much body roll and I can't find the feeling of grip and stability that I had during the first outing. I also checked to see if I had a leak, there doesn't seem to be any.

The body is lowered by 5cm at the front and 8cm at the rear.

The hardness of the damper is at its softest, like the day of my first ride with the coils. I don't go any higher because I live in the countryside of france and the roads are bad.

I would like to know if it's normal for new coilovers to become so soft after only a few rides?

Is it normal to have such a significant difference at the front and rear?

I contacted customer service, they don't seem very competent. It would be nice for me not to have to send them back because my original suspensions are dead.

Here are some photos.



Thanks for your help !

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[vig444]

here is the original height.
I would like to point out that when I adjust the hardness of the damper on the coils it works well and they harden. But it becomes impassable with the bumps and holes in the road.

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[We're on Boost]

The body is lowered by 5cm at the front and 8cm at the rear.

The hardness of the damper is at its softest, like the day of my first ride with the coils. I don't go any higher because I live in the countryside of france and the roads are bad.

The best car I ever had for driving fast on the type of bumpy secondary roads you have there was a 1970 Peugeot 504.
The reason it was so good was that it had lots and lots of wheel travel (up and down) available in the suspension, plus springs that were not terribly stiff, plus shock absorbers that were way ahead of their time in terms of good damping without being too stiff. Also those shocks lasted a long time.
I had driven around in France about 3,000 miles in 1968. Doing that I had lots of driving time following little 2CV's and every other variety of Citroen, Peugeot, etc, at 80mph or whatever speed they could do, and I always marveled at how the wheels could have so much travel up and down with so little movement of the body. And that's why I bought my 504 a few years later, in the USA.
So I don't know exactly what to tell you about your Galant but the lowering hurts it because it uses up most of your suspension travel. That 8cm in the rear, ouch, that uses up 3 inches of your rear suspension travel! There's hardly any left over for bumps!! Way too much lowering. You will be running the suspension into the bump stops probably dozens of times per minute at your road speed.

So you should put the car back up to stock height.

As far as shock life, I don't know anything about the coilovers you have, but I can tell you that KYB replacement struts have shocks in them that will last practically forever. That would probably be about 50,000 miles on French back roads. The KYB struts will place your car at stock height if you put stock height springs in them. This is how I have my 1990 Toyota set up and I like it.

I like those roads by the way. Not making fun of them at all. I wish I could go back sometime. But I'd rent a French car while there. I had a British rental that I brought over on the, I think it was a hovercraft at the time, across the channel.

 

[We're on Boost]

If you did switch to KYB struts you'd lose adjustability, so maybe you wouldn't want that. If you did though, don't get the AGX because they are way too stiff, even when adjusted full soft. I have the GR-2 struts on my Toyota and even they are pretty stiff. And now I see that the "replacement" level struts they sell are called the KYB Excel-G and it looks like they don't even make those for the rear of your car, unless it's the AWD car.
So I don't know what to really recommend for you except that I think you will need to run the car at approximately stock height, whatever you have on it, coil-overs or struts.

 

[vig444]

Hello, thank you very much for your response, your experience is very interesting, it must have been very nice to drive on these roads at that time without today's rules on a Peugeot 504!
I followed your advice and moved the car up 2cm everywhere. It's better and I noticed a slight improvement in hardness.
Thank you for your advice on the kyb, my galant was already equipped with them as standard, they are very reliable.
I live right next to the Channel near the English island of Jersey.
The roads are truly superb.
I'm going to keep the D2s for the moment after inspection it seems that there is a problem with my settings.
I'll get back to you once I've had time to review my settings from the beginning.
In any case, thank you very much for the advice and references!

 

[vig444]

Hi ! Everything returned to normal, I lowered the car as at the start. A slight softening of the coilovers is normal and the sensation was amplified by the stabilizer bar links which were completely dead! I changed them and now it's perfect! thank you for your help