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FCinWV 11-20-14 08:28 PM

Possible discovery for FC front struts
 
So during my past decade of hoarding parts I acuired a set of wheels and tires I absolutely love. However ofcourse they are 5x114.3 I want them on my FB so bad I cant stand it. So as a lot of us has done I researched and researched all the was to convert.

After messing around and doing some research I found that a Mazdaspeed 3 has the same FB ball joint measurements for the control arm and the same shank as an FC. They also make snap ring ball joints for mazdaspeed 3s.

Here is the problem lol. In my excitement I pulled my front struts off my vert and everything fit just great as far as the ball joint goes. BUT the top of the dampener on an fc is too fat for the top hat of an FB. Sooo Either I need a different dampener OR use the FC top hat and elongate the strut tower holes a little.

Obviously the alignment is way different and judging by the fitment I will need camber plates. I did a search and didnt see anyone had discovered the mazdaspeed 3 ball joints.

I hope this contributes...

http://i57.tinypic.com/2ezu3gm.jpg

http://i62.tinypic.com/6zle1x.jpg

http://i58.tinypic.com/95ogw1.jpg

rotornoob 11-25-14 12:53 AM

use the fb springs and top hat on the fc struts? ive heard that it works, but havent tried it yet. good idea with the ms3 ball joints :)

FCinWV 11-26-14 11:29 AM


Originally Posted by rotornoob (Post 11834862)
use the fb springs and top hat on the fc struts? ive heard that it works, but havent tried it yet. good idea with the ms3 ball joints :)

Thats what i did. But the fb top hat hole was to small to fit on the dampener.

elwood 11-28-14 07:43 AM

How do you plan to handle steering?

FCinWV 11-28-14 04:59 PM


Originally Posted by elwood (Post 11836013)
How do you plan to handle steering?

I will let ya know when I cross that bridge lol.

peejay 11-30-14 09:59 AM

This is really interesting! I am on the full FC frontend but I am at the limits of what I can get from the front suspension because of ball joint lock... need to fabricate new control arms that put the ball joint pivot at a different angle in the control arm. Fabricating is easier done in steel than aluminum.

Of course, I'd widen the track a bit too...

For the top hat, a Mazda-based Escort top has the same bolt pattern as FB but is designed for a fixed D-hole strut like FC. Just need to drill the strut towers to allow 10mm studs (vs. FB 8mm) and open up the D-hole to fit the slightly larger FC struts. I made my own top hats but I don't see why Escort top hats wouldn't work if you wanted to use stock type springs.

If you use the Escort hat, you will need to either cut the spring perch off of the strut and use a coilover sleeve, or use lowering springs. The FC lower spring seat is something like 2" higher than the FB relative to the spindle. This is why the FC has the funky shaped top hat/spring seat design, it allowed them to move the whole spring higher in the body relative to the strut placement.

FCinWV 11-30-14 11:05 AM


Originally Posted by peejay (Post 11836738)
This is really interesting! I am on the full FC frontend but I am at the limits of what I can get from the front suspension because of ball joint lock... need to fabricate new control arms that put the ball joint pivot at a different angle in the control arm. Fabricating is easier done in steel than aluminum. Of course, I'd widen the track a bit too... For the top hat, a Mazda-based Escort top has the same bolt pattern as FB but is designed for a fixed D-hole strut like FC. Just need to drill the strut towers to allow 10mm studs (vs. FB 8mm) and open up the D-hole to fit the slightly larger FC struts. I made my own top hats but I don't see why Escort top hats wouldn't work if you wanted to use stock type springs. If you use the Escort hat, you will need to either cut the spring perch off of the strut and use a coilover sleeve, or use lowering springs. The FC lower spring seat is something like 2" higher than the FB relative to the spindle. This is why the FC has the funky shaped top hat/spring seat design, it allowed them to move the whole spring higher in the body relative to the strut placement.

I completely agree with steel being easier to fab with. I had considered buying techno toy control arms at one point. They are 375 for a pair. My plan is to buy the techno weld on coilover setup and the camber plates. I hope that draws the camber in to a nice fitment. Right now there is a lot of positive camber. Im also running 17s ( mainly because i already had the brand new wheels n tires from my fc ). Im not overly experienced in dealing with front suspension. Its about the only thing on the entire i car i dont feel comfortable with building on my own knowledge.

One thing i wondered is the more i lower the car, would that give me more negative camber ? Its sitting way up in the air at the moment as u can see by the picture.

peejay 11-30-14 11:17 AM

1 Attachment(s)
Why would you buy a coilover setup? Clearly you're able to fabricate, and coilovers are one of the simplest things to fabricate. All you need to do is cut off the stock perch, grind down the cruft until you can fit a circle track sleeve over it, and get a generic lower threaded perch, and upper mount if you need. Pick whatever spring you want. That is unless the kit is under $200, in which case it's the better bargain.

Attachment 634754

There, so simple a doofus like me could do it. (Ignore the welding stuff. That's what it took to make rear Subaru struts fit the front of a Mazda)

FCinWV 11-30-14 12:54 PM

Well they are close. $220.

https://technotoytuning.com/mazda/fb...-sa-and-fb-rx7

peejay 11-30-14 05:47 PM

Sounds like a break-even between building and buying, so buying wins. :icon_tup:

I habitually (compulsively) buy springs in roughly the rates and lengths that suit me, because Summit often has them in scratch and dent for $20-40 per pair. Figure $120 or so new. Then Allstar threaded sleeves and lower perches were $66ish, and I have a way of making upper hats that fit the strut tops I use perfectly so no need to buy there.

$220 is a pretty darn good deal, in that light.

BezRx7 12-02-14 04:48 PM

I actually have this almost identical setup.

Fb lower control arms
80's 626 ball joints
Rx2 outer tie rods
Fb inner tie rods
Fc strut tubes
T3 weld on coilover kit & top hat
Koni 8610 inserts
Fc spindles/hubs/5 lug 4 piston brakes
T3 camber plates

Only issue you will in counter is that there isn't enough camber. I'm going to get the t3 adjustable lca camber kit to solve this.

BezRx7 12-02-14 04:55 PM

2 Attachment(s)
Some pics

Attachment 548153

Attachment 548154

FCinWV 12-02-14 09:26 PM


Originally Posted by BezRx7 (Post 11837809)




Are those Fc struts ?

if so did the tie rods work ok from the fb ?

FCinWV 12-02-14 10:12 PM


Originally Posted by BezRx7 (Post 11837807)
I actually have this almost identical setup.

Fb lower control arms
80's 626 ball joints
Rx2 outer tie rods
Fb inner tie rods
Fc strut tubes
T3 weld on coilover kit & top hat
Koni 8610 inserts
Fc spindles/hubs/5 lug 4 piston brakes
T3 camber plates

Only issue you will in counter is that there isn't enough camber. I'm going to get the t3 adjustable lca camber kit to solve this.

Wow somehow I completely missed your first post.

You literally solved my whole ridiculous search for what i needed to make this work.... Well DONE !!


EDIT: Hm I wondered if the camber plates would be enough.

The LCAs are 375

the weld on coilover kit is 220

and the camber plates are 190

about 800 bucks into T3 to get it right.

Im beginning to think i may just do the coilover kit on my FB struts and buy konig rewinds haha

BezRx7 12-03-14 02:01 PM

I used to stock fb lower control arms. 626 ball joints were like $30 and got em pressed in for free and a buddy put a few tack weld for good measure.

The fb/rx2 tie rods bolt up to the fc spindles. Just swap right to left.

T3 coilovers are almost the same. But no 5 lug or big brakes without more money. Plus I like to be difficult and do things me way :D

BezRx7 12-03-14 02:06 PM

The t3 lca camber kit in looking at is the weld in one for toyotas. It's like $99

FCinWV 12-03-14 02:27 PM


Originally Posted by BezRx7 (Post 11838158)
The t3 lca camber kit in looking at is the weld in one for toyotas. It's like $99

Oh shit I see what you are talking about now. the ae 86 kit is 180 from them.

economiser 12-03-14 02:34 PM

I ground my new FC struts to fit in my FB upper mounts. The tires will lose traction long before the grinding becomes an issue. As for the raised spring seats, it may help with fitting wider wheels, and cutting coils doesn't bother me, if done with a chop saw rather than a torch.

BezRx7 12-03-14 07:10 PM

2 Attachment(s)
Sorry for the crappy pic but had a chance to peek under the car as we're installing the new drive shaft Attachment 548190 But you can see where the tie rods are not parallel to the lca and the outer tie rod angled up and inward. This is not ideal, though it may "work". Ideally you should get some tie rod spacers like what the drifters use to drop the links and have them parallel to the lca both horizontally and vertically or you can cut, extend and angle and then weld up the steering link on the FC spindle (Nissan S chassis guys been doing this for years) Attachment 548191 (which I will prob do, but that's another story/thread - as I may be going to a 910 nissan rack next year mounted behind the crossmember where the drag link is)

economiser 12-04-14 10:34 AM

The tierods not being parallel from a front or rear view will create bumpsteer. Not being parallel as viewed from above or beneath is as it should be. Helps with Ackerman effect. If you're going to convert to a rack, front-steer drives far better than the OE rear-steer. Big brakes are cheap, whether FB or FC, but FC can go bigger. I just ordered a pair of Brembo 4-piston front calipers I paid $ 110 for, including shipping. My rotors are $ 100 / pr, including shipping. I just gotta get the 5-lug hubs, they're $ 50 / pr plus shipping. Then it's a simple matter of fabbing some adapter brackets for mounting the calipers. Any '00-'02 Mercedes-Benz S430 or S500 is a good donor for cheap Brembo fronts. So you don't need to spend big to have big brakes. The rotors I chose are 1.25" thick to match the calipers, and 11.75" to fit in my wheels, with the correct lug pattern, a large enough center bore, and the correct hat height. Only took 2 hours of searching Napa's website. Still no clue what they're supposed to fit, but larger-diameter options are plentiful.
I have Napa's part number for something cheap and easily adaptable if anyone wants to stay SA / FB and stay 4-lug. I aleady did the FC front suspension and crossmember the right way.

KansasCityREPU 12-04-14 11:49 AM


Originally Posted by economiser (Post 11838497)
The tierods not being parallel from a front or rear view will create bumpsteer. Not being parallel as viewed from above or beneath is as it should be. Helps with Ackerman effect. If you're going to convert to a rack, front-steer drives far better than the OE rear-steer. Big brakes are cheap, whether FB or FC, but FC can go bigger. I just ordered a pair of Brembo 4-piston front calipers I paid $ 110 for, including shipping. My rotors are $ 100 / pr, including shipping. I just gotta get the 5-lug hubs, they're $ 50 / pr plus shipping. Then it's a simple matter of fabbing some adapter brackets for mounting the calipers. Any '00-'02 Mercedes-Benz S430 or S500 is a good donor for cheap Brembo fronts. So you don't need to spend big to have big brakes. The rotors I chose are 1.25" thick to match the calipers, and 11.75" to fit in my wheels, with the correct lug pattern, a large enough center bore, and the correct hat height. Only took 2 hours of searching Napa's website. Still no clue what they're supposed to fit, but larger-diameter options are plentiful.
I have Napa's part number for something cheap and easily adaptable if anyone wants to stay SA / FB and stay 4-lug. I aleady did the FC front suspension and crossmember the right way.

Where can you get FC front hubs for $50 a pair?

FCinWV 12-04-14 12:17 PM


Originally Posted by KansasCityREPU (Post 11838543)
Where can you get FC front hubs for $50 a pair?

from me ! They came off my vert and have pretty much new brake pads and rotors with them :icon_tup:

would you like a brand new set of wheels and tires as well ? lol

BezRx7 12-04-14 02:54 PM

here is a couple very easy solutions for bumpsteer fix by modding the spindle

http://forumbilder.se/images/9e2201153042P08e4.jpg

and of course using adjustable tie rod ends, these are ones for a 79+ mustang, but i'm sure there are lots of options. (not even sure if these will bolt up :dunno:)

http://www.cortexracing.com/wp-conte...s-40-1000a.jpg

BezRx7 12-04-14 02:57 PM

Kansas, i've owned a S13 (and back in the day learned to drive in a 910 bluebird :P) and loved the steering feel, the 910 rear mounted manual rack may not be the ultimate solution, but having a car with factory power steering, makes the upgrade to rack pretty easy, and mounting the rack behind the crossmember makes it easier as well, so i may go down that route eventually.

economiser 12-05-14 10:26 AM


Originally Posted by KansasCityREPU (Post 11838543)
Where can you get FC front hubs for $50 a pair?

That's what Car-Part.com--Used Auto Parts Market is for.


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