BC Coilover Setup: Compression/Rebound Settings, Ride Height Adjustment, Camber, Etc.

[Dave_The_BMXER]

Hey everyone, this is my first post here but I am on a few other Mazda boards.

Anyway I switched from Sportline/Yellows to BC's on the weekend and was pretty shocked to find that I didn't end up getting any lower. I am basically at the same height I was on sportlines (perhaps slightly higher in the rear which I am ok with)

I am on 215/45/17x7s (with 38 offset) and have a finger gap in the front and none in the rear.

I have all my collars in place currently. The back sits perfect for my tastes but the front... I wish I had a 1/2" more.

My front set up looks like this photo from earlier in the thread:

So I don't think I have any more adjust-ability would that be correct?

Would I be able to get anymore drop by decreasing the spring pre load slightly?

Do these coil overs settle some? Should I wait a few days?

This is my first set of coil overs so sorry for the 100 questions

Thanks in advance.

(Height aside these perform so much better than my sportlines, far less complaining from the GF)

Here is/was my sportline drop for reference

 

[m.o.b.s.]

You could INCREASE preload by tightening the spring a little more to thread the shock body in further. I actually talked to BC today and re-confirmed the 5mm preload with them. Mine should be at least that much. My front springs with the car in the air measure 6 3/4". I don't see how 1/2 inch more could be detrimental, but your girl may complain about a stiffer ride (not always a bad thing).

Does anyone else have a measurement of their spring installed with no weight on it?

Side note for everyone...

I've developed a bongy popping noise at the top of the front right spring cause by slight horizontal shifts in the spring when turning at slow speeds...hopefully not caused by too light of a preload. Inserting little pieces of rubber to pad the inner diameter of the top of the spring kills the noise, but they get chewed up or shift within a day. BC is sending me two plastic rings with "sleeves" like the ones at the bottom of the front springs. This should make everything better.

 

[Dave_The_BMXER]

Funny, I was just emailing BC too and they said that the pre load should be set at 5-8mm from the factory.

I figure I will try and increase the pre load a bit and try to thread in a little bit more.

However BC said I can order shorter springs which I just might do. Going to take some pictures and measurements this week I will post them here as well for you gurus.

I think I just opened up a bag of worms lol.

 

[m.o.b.s.]

Just take measurements of spring length, exposed threads between the collars, etc., or whatever you need to do to return it to a specific setting in case you botch something. I quite enjoy messing with my setup, but I know exactly what to do to undo it if I don't like it.

 

[Wastegate13]

Someone had inquired about shorter springs a while back and was told that they (BC) had no intention of producing shorter springs. I would love to get another inch out of the front of mine. I'm happy with the rear but I wanna tuck the front tires.

 

[Dave_The_BMXER]

Below is what BC said to me.

"Dave
If all the rings are touching then you have it at its max drop. On the Mazda 3 the manufacture design does limit the drop. However if you want to go w a 170mm spring instead of a 180mm spring it would bring you down about .40" The preload should not have needed to be adjusted if so it should only have 5mm-8mm of preload. Settling in the spring will occur but depends on how aggressive your driving style is. It can take days to wks. If you decide to purchase the shorter springs they are $100 a pair and a $15 flat rate charge with in the 48 states. If you need further assistance please let us know.
Thanks
Mike "


and

Shipping to Canada USPS flat rate is $33 and the settling shouldn't be more than .25" The 170mm would be intended to keep you at a 7k spring rate but if you want to go to a 160mm it will give you about .75" but it would be an 8k spring. I would check the lower mount though to see how much further you have before the cartridge bottoms out in it before purchasing either.
Thanks
Mike

I am going to be taking some measurements tomorrow/familiarizing myself with adjustments and will let you guys know if I end up ordering the shorter spring (I probably will)

 

[Wastegate13]

Looks like I'll be purchasing some new front springs.......

 

[Dave_The_BMXER]

You and me both How much of a fender gap do you have up front?

 

[MM BOOST]

This is just nuts...I had mine 2 threads from all the way down and could barely get a finger in between tire and fender...and I had to put 5mm spacers on cause my coilover collars were sitting ON my tire...I don't see how you guys are wanting to go lower...nuts.

 

[Wastegate13]

This is just nuts...I had mine 2 threads from all the way down and could barely get a finger in between tire and fender...and I had to put 5mm spacers on cause my coilover collars were sitting ON my tire...I don't see how you guys are wanting to go lower...nuts.

Then you obviously don't have camber plates. In talks with other BC owners I've learned that the non-camber plate fronts are able to tuck the front tires pretty easily. Here's mine all the way down front and rear.

 

[Dave_The_BMXER]

Ya dude slightly more in the front for you would look sick.

For me being on 17s I can fit my hand flat above my tire in the front but not the rear.. me now likey.

I did not know they were available without camber plates...

 

[MM BOOST]

I definitely have camber plates, I just got mine back in October. Idk, I had to RAISE my car up to be able to drive it daily cause it was so low. My damn rally armor mud flaps were gettin stuck on speed bumps, train tracks, entrances, etc. I'm not sure what it is, but if I went any lower, I am pretty sure my tire wouldn't rotate normally lol.

 

[MM BOOST]

This is raised back up, rear collars removed and as low as they will go, front a few threads showing between collars:

 

[Wastegate13]

I definitely have camber plates, I just got mine back in October. Idk, I had to RAISE my car up to be able to drive it daily cause it was so low. My damn rally armor mud flaps were gettin stuck on speed bumps, train tracks, entrances, etc. I'm not sure what it is, but if I went any lower, I am pretty sure my tire wouldn't rotate normally lol.

Then you're roads suck. My fronts are down as far as they will go. My tires are slightly stretched so its actually a little lower than it looks, less than a single finger gap but I want the tire tucked in the front.

 

[MM BOOST]

understandable man...i was just commenting saying i couldn't phathom going any lower. your car is SEXY...haven't seen you posting as much as you used to, figure'd maybe you got rid of it or something. contact mad villain...he got the shorter/stiffer bc springs for his coils.

 

[Dave_The_BMXER]

The saga continues:

Hi Mike

I am out in the garage now and here are my findings:
The front of the car on both sides from fender to floor is 24 inches.

The gap between tire and fender is about .5 of an inch so I would like that gap gone and the fender to ground clearance to be 23.5 inches and fender to tire clearence zero.

The cartridge is way above the minimum 80mm requirement. With this information would it be advisable that I go with the 160mm spring?

Dave
Yes sorry for the delay in reply. I had one of the techs look into it and your cartridge will end up bottoming out in the lower mount and that's your first limitation. The second would be the spring. In order to make it work it would be a matter of changing the cartridge and the spring. I am going to have my R&D dept look into this and see how we can make it work. Ill get back w you tomorrow in regards to this.
Thanks
Mike

sigh...

 

[Dave_The_BMXER]

Dave
The springs will not do it for you it will have to be a combination of spring and cartridges. It would run you $95 each cartridge and $100 for the pair of springs. Let me know if you need further assistance.
Thanks
Mike

300 + dollars for 1 inch...

 

[Wastegate13]

Dave
The springs will not do it for you it will have to be a combination of spring and cartridges. It would run you $95 each cartridge and $100 for the pair of springs. Let me know if you need further assistance.
Thanks
Mike

300 + dollars for 1 inch...

Well if you are in my boat and sold your stock suspension then reacquiring that and buying another set of coilovers, then selling the BC's would run more than 300 bucks.

 

[Dave_The_BMXER]

I was just figuring 300 + my coilover buyin from my sportline/yellows.

Either way I will probably do it because... well... god damn cars.

 

[Wastegate13]

I was just figuring 300 + my coilover buyin from my sportline/yellows.

Either way I will probably do it because... well... god damn cars.

I know exactly how you feel. I've been thinking lately of selling my wheels and picking up something cheaper. Figure I need something to spend the difference on. lol