Manual Steering Rack Interest and Input for 818R

[Sgt.Gator]

I posted this in the Steering section but it's really more for the folks who will be racing their 818Rs. Sorry for the dual postings but I wanted to be sure to hear from 818R builders.

I need your input for custom manual steering racks for us. Quaife will make them anywhere from 2.2 to 3.1 turns lock to lock. Those of you with the STi racks (2.6 turns LTL), if you could choose a faster one, say 2.4 or 2.2 would you rather have that?
I'd love to have input from everyone who has tracked their cars about your steering ratio feedback. I'm most interested in 818R builders since a quick ratio rack & pinion setup may be a bit of a pain on the street for parking, but much better on the track.
Thanks!
Gator

[Mitch Wright]

Will be watching this thread with interest, I am 6 months from turning a wheel.

[Scargo]

I started a similar thread called "Aftermarket Steering Rack?", perhaps before the 818R discussion section was started?
I mentioned how the STi's steering ratio is 15:1 vs the WRX at 16.5:1. Now the new WRX is 14.5:1 and the new STi is 13:1!

None of this is going to do us any good in selecting a rack if we don't know the length of the steering arm that we have.
Since I'm likely to go with the Palatov upright I can have the arm be anything I want. It is stock at four inches.
A spec Miata builder/racer suggested I look at the Miata's steering rack. 1990 and up looks to have a larger rod diameter that earlier years. Spec racers are "depowering" power steering units to manual, just like with a Subie's. They have a 2.8 turning ratio whereas the harder to find (and less used in racing) manual has a 3.3 ratio. That's like 30 degrees vs 35 degrees for the same steering wheel input. Doesn't seem like a lot of difference... Here again, I do not know the Miata's steering arm length.

Used Miata racks can be had for $100 to $150 it looks like. I would say I am leaning in that direction. They seem to hold up pretty well in racing. The Miata is slightly heavier than an 818, but not by a lot (about 300 pounds?). It has more weight in the front. I think the steering rack is a pretty good fit and not too lightweight.
I'd really like to know the steering arm length of a WRX so things can be compared, apples to apples. I don't want to be getting into something that steers slower and I can't shorten the arm enough to compensate.

[SixStar]

$250 or so for the rack and pinon?

[Scargo]

No, I said "Used Miata racks can be had for $100 to $150"...

Today I found I had a spreadsheet for steering ratios based on steering arm lengths. It appears that at 2.8 and a four inch long arm length you will have less than a 9:1 ratio. That's quick! Probably too much so. Even a Caterham is 10.4:1.
If I lengthen the arm an inch to five inches I am around a very approachable 11:1.
Would still like to know what the length of WRX arms are. No one else is curious? No one else interested in Miata racks?
I'm still thinking about an aftermarket rack and pinion. Direct. No slacking off.

[SixStar]

I was asking about the Quaife price. Their OTS kits are about that much for most makes and models.

[Sgt.Gator]

I can't get a price from Quaife. They want me to send them an OEM rack, then buy thru a particular US distributor who so far has not returned my emails. I'm thinking now it might be easier to get a custom rack setup for the 818 from Flaming River. But their modular billet racks are $800.

[Scargo]

I am still squirming around, undecided. I like the idea of an aftermarket rack and pinion with it's direct, gear drive. I couldn't find anything Quaife that would apply and when you find something it is usually with power steering.
"Flaming River" name scares me... Is it 'Merican? Chinese? There's circle track stuff out there. Coleman looks interesting. I need to call them. I have no idea what is decent quality and then offers the ratios we need and the travel. Prices for some of these seem reasonable.
There's no way I'm paying big bucks for something new (designed for a Subaru) when the fallback is that I can use a Miata rack or similar...

OK, so Flaming River is made in USA... my bad.

[xxguitarist]

Scargo,
If you were to change the mounting area of the steering rack to something level with the ground, you could have a variety of arm mounting holes, similar to a swaybar stiffness adjust.. You'd just need something to extend the splines on the universal.

I'm a little concerned also that our rack may be a little slow for auto-x too, but it will probably be a project for next winter once we have evaulated & determined there's actually a problem.

[Sgt.Gator]

It's the Quaife QSH5Q Quick Rack, LHD.

[RM1SepEx]

Scargo,
If you were to change the mounting area of the steering rack to something level with the ground, you could have a variety of arm mounting holes, similar to a swaybar stiffness adjust.. You'd just need something to extend the splines on the universal.

I'm a little concerned also that our rack may be a little slow for auto-x too, but it will probably be a project for next winter once we have evaulated & determined there's actually a problem.

Is your Miata a manual rack or a de-powered power rack? I think the NA manual rack is 18:1 and the power rack is 15:1
WRX - 16.5:1, 3.0 turns lock to lock, the STI is a wee bit quicker at 15.2:1 2.7 turns lock to lock (My data could be wrong)

So we should be in the correct range with either de-powered rack.