BC Racing Coilovers for Mazda 5 - Unboxing

phunky.buddha

Booga Booga?
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DFW TX
:
No mo MZ5 want MX5
UPDATE! Install / Review thread here: http://www.mazdas247.com/forum/show...R-Type-Coilovers-Mazda-5-(Review-and-Install)

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So I bought a set of BC Racing Coilovers for the wife's Mazda 5 from Import Auto Performance and got them in over the winter break. With all the vacations and my crazy work schedule, I just got around to digging around in the box and thought I'd share with all of you guys. And before anyone asks, no, I don't work for IAP, but I have to let everybody know that their customer service has been great with REALLY fast responses both over the phone and through email and forum private messaging on the sites they have a presence. I've been nothing but satisfied so far.

I'll have a giant installation how-to thread once I get these things on, but first let me share my rationale for buying this set of coilovers vs other options.

1. Price. Ultimately, the dollar count is what matters most to quite a few people. The price point on these things is $1000 shipped. My other main option was Koni Yellows and H&R Sport springs which would have checked out at around $900 shipped. With all the reading I've done on the forum, quite a few people have been reporting broken mounting hardware when they've gone to change out their struts, and needing to spend another few hundred bucks replacing everything. I have weird clunking sounds coming from the front end of my wife's 5 now, so I might have something broken up front. If I do, these coilovers take those parts out of the equation since none of the OEM mounting hardware is used. Replacement shocks/springs do not.

2. Spring rate. I likes my go-karts. :D BC and one or two other companies actually offer MZ5 specific spring rates. BC specs the MZ3 at 7kg/mm front, 4kg/mm rear. The MZ5 part number is sold with 8kg/mm front and 7kg/mm rear springs. The Yellow Speeds are 8kg/mm front and 6kg/mm rear. More rear rate = more fun for me.

3. Adjustability. I've had coilovers before where the height and spring pre-load were independently adjustable. It's a nice feature to have. The real reason to have independently adjustable shock body length and spring perch height is to be able to corner weight your car while keeping your ride height looking how you want. Will I corner weight the family car? I have a buddy with corner scales, so maybe, just maybe.

4. Reviews. BC seems to have some of the best feedback out of anything else in this price range for inexpensive coilovers. No, these aren't crazy $5k+ competition coilovers, but they seem to be pretty popular in almost every forum for cars that they make an application for. I'll at least be able to compare them to the Tein Flex that were on my Civic and retailed out around $1600, plus the AST 4100s that are on my S2000 and peg out close to $3k.

I guess that's enough blabber for now- on to the pics!

Box the way it ships- double boxed, straps everywhere:
mz5_bc_unbox_m_01.jpg


Part numbers on the outside along with spring rate information- these are 8kg/mm front, 7kg/mm rear:
mz5_bc_unbox_m_02.jpg


Invoice straight from Bor-Chuann, looks like a declaration of $150 might get you past customs a bit easier ;)
mz5_bc_unbox_m_03.jpg


Red box inside brown box:
mz5_bc_unbox_m_04.jpg


Paperwork inside, lots of Chinese, installation instructions, product pamphlet, sticker:
mz5_bc_unbox_m_05.jpg


How they're packed- never seen peanuts inside bags before:
mz5_bc_unbox_m_06.jpg


One front and one rear laid out:
mz5_bc_unbox_m_07.jpg


Front lower, shows the tag and model type:
mz5_bc_unbox_m_08.jpg


Front spring info; the way I read it is 62mm coil diameter, 180mm coil length, 8kg/mm rate:
mz5_bc_unbox_m_09.jpg


Model specific tag on the front:
mz5_bc_unbox_m_10.jpg


Hardware mounting tabs welded to the lower sleeve:
mz5_bc_unbox_m_11.jpg


Top mount with camber plate- these are not in the application guide for the MZ5, but I asked for them anyway and got them:
mz5_bc_unbox_m_12.jpg


Rear tag:
mz5_bc_unbox_m_13.jpg


Rear top mount with adjuster:
mz5_bc_unbox_m_14.jpg


Rear dust boot, bump stop:
mz5_bc_unbox_m_15.jpg


Bushing at bottom of rear shock:
mz5_bc_unbox_m_16.jpg


Rear spring stackup:
mz5_bc_unbox_m_17.jpg


Rear upper adjustable perch:
mz5_bc_unbox_m_18.jpg


Rear spring- 62mm coil, 180mm length, 7kg/mm:
mz5_bc_unbox_m_19.jpg


Rear lower perch, top side:
mz5_bc_unbox_m_20.jpg


Rear lower perch, bottom side:
mz5_bc_unbox_m_21.jpg


The sticker:
mz5_bc_unbox_m_22.jpg


It's actually made of metal:
mz5_bc_unbox_m_23.jpg


Overall I'm quite impressed with what came in the box, especially for the price they want. The build quality looks good, the camber plate is really nice, and the large chunky metal pieces look well formed. Hopefully all these pictures give you guys a better view of what the coilovers really look like in the flesh as opposed to the same promo pictures you see on every web site.

I can't wait to get them onto the car and settled in to see what they're capable of. I just have to get my OTHER coilovers back and get this thing backed out of the garage... suspension installs outside are a little cold in the winter.

:)

s2k_garage_m.jpg
 
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Looks great. Forgot about these coilovers, glad they have a Mazda 5 specific model. My shocks are long gone so I'll have to replace them very soon and I want to drop my car about 0.75" front and 0.5" rear anyway. How is the height adjusted on these?
 
Nice!

Thanks for the pics, definetly will help in the decision making process. Still comparing them to the Yellow Speed coilovers (see my other post for other choices). But it is always nice to see someone else who has them and speaks highly of them.

PS thanks for all you hel last night regarding these.
 
Looks great. Forgot about these coilovers, glad they have a Mazda 5 specific model. My shocks are long gone so I'll have to replace them very soon and I want to drop my car about 0.75" front and 0.5" rear anyway. How is the height adjusted on these?

You spin the lower body of the shock up and down without touching the spring perches. On the rear, you adjust the shock length the same amount as the spring perch.

Nice!

Thanks for the pics, definetly will help in the decision making process. Still comparing them to the Yellow Speed coilovers (see my other post for other choices). But it is always nice to see someone else who has them and speaks highly of them.

PS thanks for all you hel last night regarding these.

No problem!
 
Thanks for posting!
1. Price. Ultimately, the dollar count is what matters most to quite a few people. The price point on these things is $1000 shipped. My other main option was Koni Yellows and H&R Sport springs which would have checked out at around $900 shipped. With all the reading I've done on the forum, quite a few people have been reporting broken mounting hardware when they've gone to change out their struts, and needing to spend another few hundred bucks replacing everything. I have weird clunking sounds coming from the front end of my wife's 5 now, so I might have something broken up front. If I do, these coilovers take those parts out of the equation since none of the OEM mounting hardware is used. Replacement shocks/springs do not.
I am now starting to experience this too. I think it is more than coincidence that it started happening (for me) now that temps have fallen.

3. Adjustability. I've had coilovers before where the height and spring pre-load were independently adjustable. It's a nice feature to have. The real reason to have independently adjustable shock body length and spring perch height is to be able to corner weight your car while keeping your ride height looking how you want. Will I corner weight the family car? I have a buddy with corner scales, so maybe, just maybe.
It would be great if you can corner weight the car before any mods! Ive always been curious what it actually weights and F/R ratio (not relying on internet pubs).


Some questions on the BCs :D
-Is there an option for different spring rates from BC when you order?
-They come with progressive or linear springs (only one rate is printed on the spring but I think they are progressive)?
-Can you measure the ID and height of the springs to see if you can get something else from a mainstream spring vendor?
-Do you know of any dyno charts for BC dampers, or did it come with the package?
-Are the front shocks inverted? Couldnt tell from pic since you have dust cover on and the body seems on the smaller side.
-Dont see bump stops for the front. Are they built-in? If yes, then they are probably inverted. Is there an access nut on the bottom of the fronts to take it apart to get to the bump stops?
 
Thanks for posting!
I am now starting to experience this too. I think it is more than coincidence that it started happening (for me) now that temps have fallen.

Welcome! Lower temps do tend to make the rubber parts complain more.

It would be great if you can corner weight the car before any mods! Ive always been curious what it actually weights and F/R ratio (not relying on internet pubs).

I'll try- have to see who has the scales right now. It took me a couple reads though- usually when you see "corner weight" used as a verb, it means to balance out the car, not just measure the cross-weights.

On second thought- I probably won't weigh the car before I install anything. It would most likely mean a few weeks' delay for the install, and if I have time to put them on this weekend, I'm doing it. Install Sunday/Monday means it won't be done on a flat slab (S2k still on jacks in the garage), so there's no way to weigh the car properly, even if I could get my hands on a set of scales.

Some questions on the BCs :D
-Is there an option for different spring rates from BC when you order?

I didn't ask, but I assume you can get whatever rates you want. I'll try the stock rates- I have other sources for springs if I want to try different rates later, but I think I'll be ok what what's in the box.

-They come with progressive or linear springs (only one rate is printed on the spring but I think they are progressive)?

They're linear front and rear- they sure as hell don't look progressive to me, and they're advertised with specific 8k/7k rates. Most progressive springs are sold without an advertised rate, or they show the min/max rates over the spring.

-Can you measure the ID and height of the springs to see if you can get something else from a mainstream spring vendor?

I can't measure the proper ID of the front springs without taking everything apart (which I'm not going to do), but the rear springs have about a 65mm ID at the end coils, and a coil thickness of about 10mm. The fronts look to be dead on with a standard 62mm ID spring (and 62 is what's in the part number), so I assume that's what they are. They look pretty much the same as the 62mm ID Hyperco springs I have extra for my S2000. Both front and rear springs measure out at 180mm. The rear springs are free, so those are a dead match for the part number; the fronts are between perches, so I don't know what preload they have on them (probably just enough to prevent vibration, so nothing significant)- but they match up with the 180mm in the part number too. No reason to doubt the "62.180.xxx" part number convention.

-Do you know of any dyno charts for BC dampers, or did it come with the package?

Yup, and nope. I've seen dynos for the BCs- they're not the greatest if you're looking for competition dampers... but these aren't specialty $5k shocks. They do well on shock dynos against other offerings in this price range, and the adjuster do actually do something, but they're not the super nice response curves that you're going to get out of a sweet Moton or something like that. I'll post the dynos for my ASTs when I get them back in a week or two- for the BCs, you'll just have to Google them up. They're out there, I promise! I'm pretty sure that whatever BC dyno you find will also apply to these- the BCs (and most other "fully adjustable" coilovers at these prices) typically use universal shock cartridges for quite a few different applications. Whatever you find though, I'm sure that the BCs will compare favorably to coilovers a good bit more expensive... and they can also be revalved (for some $$$) to behave exactly how you want too.


-Are the front shocks inverted? Couldnt tell from pic since you have dust cover on and the body seems on the smaller side.

Shafts are up top under the dust boots, business end is down low.

-Dont see bump stops for the front. Are they built-in? If yes, then they are probably inverted. Is there an access nut on the bottom of the fronts to take it apart to get to the bump stops?

Think they're internal. I don't want to take them out of the box again (just did it 2-3 times in the last 10 minutes to take measurements for you, will check on install), but the shocks are user-rebuildable, so I'm sure you can take them apart to get to whatever external hardware you see.
 
:)

Looks like the install won't be this weekend... haven't gotten around to brake fluid reservoir move or giant spinning hole saws yet.
 
Ugh, they won't fit through otherwise? The reservoir just needs to be moved out of the way during work.
 
Did a little reading up on the BC (from other cars) and they do seem like a very good value. I like that replacement cartridges are <$100 and pretty easy DIY replacement. I hope you get to try them out on some not-so-smooth roads b/c our roads in NE is pretty ugly. I've been to TX a few times and there's no comparison :(.

http://www.iwsti.com/forums/gd-susp...rs-anyone-replace-shock-cartridge-insert.html
Note this is a non-inverted shock (Mz5 rear) but the process and parts should be the same for the front.


I did find dyno charts via google image search. Not the greatest but not bad for the price!
 
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since im also running BC coils on mine ill give you a few pointers..

remember to set your camber adjustments for the front PRE install.. if you dont you WILL have issues with the install.. the holes at the top of the strut towers are not large enough to get to the alen bolts to loosen and adjust.. i suggest more than anything getting a grinder and cutting a slit across for a flat head to fit,

also these do go fairly low, im only able to tuck tire in the front about 5mm,

finally depending on wheels be very careful, the BC coilover housings are a wider diameter than stock and if you were running a 18x9.5 38et offset like i was you will need about a 3-5mm spacer to fit your wheel...

if you need some advice let me know, my fronts are fully slammed as low as i can go without removing collars and i wish i could go lower now...

rears are set about 1/2 from highest max height to keep the car looking even.. no joke.. the rears will go LOW.. almost to about a inch off the ground with stock side skirts.
 
Ugh, they won't fit through otherwise? The reservoir just needs to be moved out of the way during work.

They'll fit through- just want easy access to the camber plate and damper adjusters without moving things out of the way.

since im also running BC coils on mine ill give you a few pointers..

remember to set your camber adjustments for the front PRE install.. if you dont you WILL have issues with the install.. the holes at the top of the strut towers are not large enough to get to the alen bolts to loosen and adjust.. i suggest more than anything getting a grinder and cutting a slit across for a flat head to fit,

also these do go fairly low, im only able to tuck tire in the front about 5mm,

finally depending on wheels be very careful, the BC coilover housings are a wider diameter than stock and if you were running a 18x9.5 38et offset like i was you will need about a 3-5mm spacer to fit your wheel...

if you need some advice let me know, my fronts are fully slammed as low as i can go without removing collars and i wish i could go lower now...

rears are set about 1/2 from highest max height to keep the car looking even.. no joke.. the rears will go LOW.. almost to about a inch off the ground with stock side skirts.

Not looking to slam, just even up the gap- probably the same drop as the H&R springs. I am going to run 235/45 tires on a +55 offset though, so we'll see how much clearance I have after the install. I might have to run a spacer up front with a roll to clear everything.
 
I wasn't planning on it, but I'll take a look when I'm down there and see if they need to be swapped out. Is it a common item to break down there?
 
Nope, last weekend was pretty busy with family being in town, and while putting the ASTs back into the S2000 it took me a while to realize that all the dark fluid in the trunk wasn't what I thought was oil... it was blood flowing out of my hands from some really sharp cuts I got while working with low light and no sleep at 4am. Yech.

S2k get finished up tomorrow night, 5 hopefully immediately afterwards. At least I have my truck to stuff the kids' seats into for the weekend so I can take my time and do the install right.
 
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