22 replies to this topic

[gtred]

I noticed that some use a manual rack and some merely depower the rack. Any advice for a new build? (2004 NB)

[Caveman-kwebb99]

Depowerd is by far the most common. I think its around $500.00 plus shipping for the manual rack.

[davew]

The NA manual rack was uncommon as it only came on stripo, base model, steel wheel, zero option cars.
The NB manual rack is pretty rare as it only came on the race version, I don't remember what terminolgy they used for the car. I think it is available from Mazdaspeed for about $500

De-powering the rack is BY FAR the most common way to go. I have plugs that make this a $17, 5 minute job. This is discussed on page 17 of the Spec Miata Constructor manual

Dave

[FTodaro]

I read someplace that the lock to lock ratio in the power rack is better shorter than the manual rack. do not know if its true, just remember reading it.

[davew]

The power rack is fewer turns lock to lock, which slightly increases steering effort. If the power rack requires 30* of turning, the manual requires 35*

If you are used to the depowered rack, and hop into a manual rack car, the manual car will feel sluggish at turn in. Untill you get used to the extra movement.

Dave

[Jim Drago]

I like the manual rack personally as when I started, I used to gorilla hand a bit.. I like that I have to turn the wheel a little more than the de powered rack. But driven both ways and very little difference. More comfort and what you get used to than anything. I use the manual racks in my personal cars, but 99% we build get depowered racks

Jim

[Phil Mather]

I used Flyin' Miata's method (http://www.flyinmiat...depower.php?x=1) plus I had the pinion shaft and gear TIG welded to get rid of the power steering torsion bar lash. 2 years of Michigan streets and track instruction time and no issues.

[Jim Drago]

Dave or anyone else...
Have you ever tried disassembling 90-97 manual rack and inserting shaft and pinion ion a 99 power rack? I wonder if it would work? Probably not.. Just thinking.

[LarryKing]

I switched from a depowered rack to a manual rack last year - I prefer the feel of the manual. Plus it's lighter, and less weight over the nose is a good thing.

[davew]

In my 12 years of SM, doing 20 events per year, averaging 10+ cars. I have had 2 steering racks fail. Both had the flyin Miata depower system as Phil mentioned. Coincedence, maybe. But I don't see the advantage worth the risk.

Jim, interesting thought. If it would work, that would be great. I kinda doubt the shaft sizes would be the same. If I had a NA manual rack, I would try it. But, I do not

Dave

[forestdweller37]

In my 12 years of SM, doing 20 events per year, averaging 10+ cars. I have had 2 steering racks fail. Both had the flyin Miata depower system as Phil mentioned. Coincedence, maybe. But I don't see the advantage worth the risk.

Jim, interesting thought. If it would work, that would be great. I kinda doubt the shaft sizes would be the same. If I had a NA manual rack, I would try it. But, I do not

Dave

Could you describe the failure mode of the Flyin' Mata racks?
Thanks

[Phil Mather]

Could you describe the failure mode of the Flyin' Mata racks?
Thanks

I'd be interested too!

[davew]

In both cases, chipped teeth on both the rack and pinion gears. Hard to describe, but it felt like dead spot in the steering and would 'click' when turning wheels.

May be coincedence, but I have only had 2 racks fail (without collision damage) and both where FM modded racks. IIRC, those are also the only 2 FM racks I have dealt with.

Dave

[MPR22]

Those fylin miata guys sure know how to make a 2 minute job take all day. Buy Dave's plugs, install, go on with the real important prep work, like figuring out decals make your car look better.

[DrDomm]

I like the manual rack personally as when I started, I used to gorilla hand a bit.. I like that I have to turn the wheel a little more than the de powered rack. But driven both ways and very little difference. More comfort and what you get used to than anything. I use the manual racks in my personal cars, but 99% we build get depowered racks

Jim

Do you remember if my car (your 2006 car) has the manual rack? Otherwise, how do you tell? It must be must be missing some hydraulic input, right?

[forestdweller37]

Do you remember if my car (your 2006 car) has the manual rack? Otherwise, how do you tell? It must be must be missing some hydraulic input, right?

I'm not Jim, but if you look at the area of the rack just below the steering shaft universal joint, it will either have a couple inches of exposed shaft (manual) or some housing with looped or capped off hydraulic line (power). This would be in the area under the hood forward of the exhaust header on the driver side of the engine. The joint may still be enclosed in plastic bellows.

[Jim Drago]

Do you remember if my car (your 2006 car) has the manual rack? Otherwise, how do you tell? It must be must be missing some hydraulic input, right?

I believe it did.. see message above.
Jim

[DrDomm]

I believe it did.. see message above.
Jim

Cool. I'll check later.

[Alberto]

FWIW, a bunch of my Rx7 buddies have had the power steering rack converted to full manual by Maval Gear.

Maval is a steering gear company. Their conversions have been proven on track over the last 10 years or so that the RX7 community has been converting to manual steering.

[Funracer]

I have a manual rack. Can't say much for how it drives
relative to a power rack as I have never raced with the latter.

What I can say is the manual rack uses a different sized tie rod (NA , not sure about
newer cars). If you break one it can be difficult to source on short notice.
It happened to me a couple of years ago. Many SMers kindly offered to sell/trade/give me
one but every other car at the track had a power rack. The local AutoZone had many
power steering TRs but no manual TRs in stock. My newbie mistake cost me alot of track time.

In addition to that they are more expensive if you can find one- like twice as much.

You get the point. If you go with the manual rack be sure to carry spares. I do now.

Good luck with your new build.