MazdaMike02

iTrader: (4)

Hey guys. Okay Ive been pondering this and I cant decide. So I need opinions and experience.

I have an 85 GSL. Now, I have Eibach springs, Tokico Inserts, RE Speed big brake kit yet to be installed..I also have a CP Racing Rack and Pinion kit yet to be installed.

Now heres the dilemma. I also have an FC subframe, struts, TII brakes and....a super rare Manual Rack and Pinion from an 88 base.. Not sure what ratio but very quick for sure..effortless steering at slow speeds.

So should I just sell the big brake kit (front), CP Racing rack kit and other FB suspension stuff and install the FC stuff? I mean it would be easier to install the FB stuff..but what would be the better choice?

orion84gsl

iTrader: (5)

The FC stuff will give you more options for steering upgrades and suspension choices. I would prefer the separate hub/strut combo of the FC if I hadn't already gone with the RE-Speed rack kit. From what I've read the FC rack isn't bolt in, but it's not overly difficult either. I've also read the CP rack kit is garbage. But I've never seen one installed or otherwise.

peejay

The FC steering is slower than FB.

RGHTBrainDesign

Weird, I know we've talked about this before and you know from first hand experience, but really?

FC: 15.2:1 (Powered) or 17.4:1 (Non-Powered)
FB/SA: 17-20:1 Variable (S1/S2) or 15.8:1 (GSL-SE/S3)

Depowering the FC box would be fastest. I'm sure there are tons of other boxes that fit reasonably well too.

References:
Project rx-7 | The RX-7 (1st Generation) History.
https://www.rx7club.com/2nd-gen-arch...ht-way-440198/
1st gen steering upgrade - Page 2 - NoPistons -Mazda Rx7 & Rx8 Rotary Forum


Cheers.

peejay

I have an un-powered FC 3-port rack and it's slower than the S3 power box, in the same car. It takes more steering wheel angle to effect the same directional change. It's one of the few things I don't like about the FC suspension (along with limiting engine options and the poorer suspension geometry)

I know what the numbers say, but there are other factors in effect.

BTW - The steering is still ridiculously light. It's less effort at the fingertips than most cars with power steering.

DreamInRotary

iTrader: (49)

Funny, because I could feel this when driving the FC around before tearing it down. Super interested to see how it feels in the FB.

I'm going to be doing a full S4 TII un-powered subframe swap with everything. That's the route I'd take personally.

Only hitch with that route is converting the rear to the FC bolt pattern with RE-Speed under the weather...

autobahn_don

I get the feeling that almost any manual R&P steering system in these cars is fab. Having a tiny little rotary engine sitting way back in the engine bay helps

I run a depowered rack in the 944. You really feel that weight at low speeds.

To make any depowered setup good, you have to get rid of any damping systems that are built in and operate via hydraulics.

Sounds like you have good manual setups though. I'd go with whatever is quicker. These cars are so light that city drivability isn't really an issue.

j_tso

iTrader: (2)

Where would you get a CP Racing kit?

Look in the feedback section, RE-Speed is having issues delivering parts (in that they're not).

Since you already have an FC subframe and extras, I say go with that.

I have an RE-Speed kit in my car and like it. Only drawback is the turning circle has increased more than a little bit.

Whizbang

you can buy the Moser axles directly from Moser. And either run GSLSE calipers and just redrill some rotors or make a bracket to hold whatever caliper you want.

I have the FC swap with a power rack in my rally car and frankly, i like it more than the FB stuff. The FC suspension options are great (coilover! real ones!) and you can even use FC camber plates if you just oval the chassis holes for the strut top a little.

Over a non power FB especially loved it. the old steering was pure junk, and the parts are weak, the brakes are weak, and the options for suspension are drying up.

MazdaMike02

iTrader: (4)

Lol I already have the axles and they're installed and ive got Re Speed big brake kits from and rear installed. Also already have tokico inserts and eibach springs installed. And I have everything required to install the cp racing rack and pinion kit..just thinking maybe it would be better to sell all that stuff and install the FC stuff which I already have too..

MazdaMike02

iTrader: (4)

Ps I have an OEM Manual (un-powered) rack and pinion from an 88 base..lol you guys are saying to depower but I already have the manual rack lol.

I just wanted some opinions and answers from people who have experience with both. So I'm thinkin I'm gonna install the stuff I have and feel for myself. Most likely though I'm gonna install the FC stuff when I get around to it.

MIKE-P-28

iTrader: (1)

I was kinda under the impression that re didn't make the axles anyway. They are made out of shop by somebody else

MIKE-P-28

iTrader: (1)

I'm ***** deep in the FC goodies swap. I'm about done with it. It's an extremely easy swap. From a dimensional strength point of view I think the FC subframe really shores up the frame rails by triangulating it in several points where it needs them. The 12a setup I laughed at when I dropped the cross member. Four 10mm threaded studs a few inches apart in the extreme front of the vehicle? My subframe is held in with four 12mm grade 10 bolts thirteen inches apart. It's got to be way way stronger. Plus no bullcrap finding 13b oil pans, GSL SE front covers etc. any mid mount 13b will drop right in. Actually tho, I raised mine in. Slide the entire completely assembled crossmember, engine, trans under the car and raised it up into the car. Easiest motor I'd ever put in. Getting all the hoses and lines in on the drivers side takes a bit of cutting on the radiator left side piece but it fits great.

82transam

iTrader: (18)

I have zero regrets about ditching the re-speed setup for my FC subframe. I've put close to 10k miles on it over the past few years and love it.

I would do it again in a heartbeat (and will be on my other FB at some point in the future). Like others have said, even if you kept the FC parts stock it would be a big upgrade, add in the fact that FC aftermarket parts are much more readily available and you've got no reason not to...

peejay

What car did you do this on? Mine had 12mm studs and bolts. I re-used two of the tension rod mount bolts as my rear subframe bolts.

The FC subframe is weaker. The SA/FB setup loads the body in tension with compression loads straight across the subframe. The FC loads the subframe in tension with compression loads across the cantilevered part of the subframe.

I went to make a control arm angle change spacer (similar to the anti lift kits sold for Subarus) and found that my subframe is all twisted and tweaked. The rear ends are no longer in line or parallel with each other :/

[quote] Plus no bullcrap finding 13b oil pans, GSL SE front covers etc. any mid mount 13b will drop right in. /QUOTE]

Meaning you have to use an FC engine. I'd like to use a 12A center iron in my 13B for the added port area but I can't because I'm married to that mounting point. (And the GSL-SE does not lend itself to making a STRONG motor mount)

12A covers fit all flavors of 13B no problem.

MIKE-P-28

iTrader: (1)

83 GS they are welded in studs 10 x 1.25 mm

I disagree with the reinforcement argument. Kinda like a piece of 20 gauge and then a piece of 20 gauge that's bead rolled. Way stronger against the beads.

Whizbang

pete,

curious how you managed to bend the subframe in such a fashion... i dont know any stage rx7s that have bent any frames, FB or FC...

if you have the spacer in the rear since there is a Y plane factor?

peejay

Could be it.

Mind you we run ROUGH courses, I ignore the rough spots (let everyone else slow down, I won't slow down) and I have a bad-driver habit of being too late and heavy on the brakes. Hitting large ruts and such with the wheels locked is just about the worst thing you can do suspension-wise.

To give you an idea, the only time I've even heard of a DMS strut breaking its ears was at one of our local rallycrosses...

j9fd3s

iTrader: (3)

there isn't a ton of info on this, but there is an SAE paper about the FD body design, and they found the FC front sway bar actually makes the chassis less rigid.

if you think about it a little, the sway bar is less of a sway bar than it is a cantilevered frame twister...

i think the car in the graph is an FC, but they don't specifically say. its a neat test, they support the car on one corner and remove parts and measure how much it bends....

MIKE-P-28

iTrader: (1)

From my point of view the only place I see any weak point from mounting the FC frame in there is : It mounts and triangulates a large potion, actually the whole front, of the car against the frame rail against the firewall (the part that angles downward) where it meets the floor pan and the thin tinny frame rails under the car... What Im going to do before I start driving it a lot is trace and cut matching pieces of 1/2" plate the same size as the steering box mount and the idler arm. I'll make the pieces angle down more towards the rear of the frame. I'll bolt these in using the existing 3 bolt points for the steering box and the idler arm. 'IDEALLY' one would be really wise to make ear pieces welded off the sub frame and weld or attach them frame rails on the inside. It would be extemely rigid that way. But ideally the traingular pieces traced and cut from the steering box and idler will strengthen the torsional rigidity of the frame a great deal. Im sure with these and a homemade strut bar this car isn't flexing at ALL.

I can tell you this now Before with the 12A setup. Jack up the cross member and the strikers on the front door begin to hit the door latches when you open the doors. Passenger side was REALLY BAD. Now with the way its mounted now and with the 13B and all, there is ABSOLUTELY NO RUBBING at all. Its more solid, well at least from a vertical inclnation stand point.

peejay

My doors don't open unless the car's on flat ground

It's really time for a new shell but FBs have gotten retarded-expensive.

Whizbang

maybe you also have some rusting issues that have weakened the car? out here we have my car, a friends pavement beater (82 with fc subframe and MSP engine) and weaver has his 2.2 subaru powered FC sub'ed FB in OR too. No problems to date.

at least out west FBs are still uber cheap.

DMS wise, i have seen plenty of bent ears! something with the subaru's wonky angled ears (which they did away with on WRC cars... hmm) and then they won't back up their warrenty either...

we shall see what happens with mine if i can ever get that thing to a rally. Mt. Hood in october is kinda my goal. its a one day, but pretty fast and rough gravel here and there.

That said, i still love my 2.1 turns lock to lock with the 1.5:1 reducer on a 3 hole rack running off the miata power steering pump. my rack needs replaced however since its leaking... but still. awesome.

in a sense i could see how the sway bar ISNT going to stiff the body since its suppose to translate the force between the wheels.

j9fd3s

iTrader: (3)

that is exactly whats going on, and its cantilevered out on frame rails designed to bend (in an accident) as well

Whizbang

looking at my Rx-2 (which im 1/2 through stuffing an FC subframe into) seems like that had the same arrangement there by mounting to the frame. Granted, the Rx-2 then was integrated into the arm with a bushing like a lot of german cars do. Maybe its a product of a forward mounting swaybar trait?

Kaaarl12a

iTrader: (6)

Would it be possible to do the fc sub frame and keep the 4x110 hubs?

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