De-powering the steering rack, plus more to come on rebuilding wrx parts

[GUNS]

^ potentially. I'm almost wondering if a quicker steering response may result in a twitchy behavior at high speed. I think with a de-powered rack and the light weight it will all ready be responsive...a quickener may be overkill.

[Xusia]

I think we are talking about 2 different things. Depowering allows for more direct feedback from the tires to the driver through the steering wheel. Less vehicle weight means less effort needed to turn to the wheel, which only really matters without power steering anyway. But neither of these affect the number of steering wheel turns lock-to-lock, so they are not "quickening" the steering (which increases the amount of wheel turn relative to the amount of steering wheel turn). It should be noted that quickening the steering is reducing the leverage of the steering wheel on the tires, and therefore results in increased steering effort. This is important - relative to your comment above - because the slightly higher steering effort helps combat twitchiness. It can also help reduce over-corrections in steering.

I hope this helps.

[RM1SepEx]

I'm sure that they are using the stock depowered rack and un modified steering arms on the front uprights. It should be fine... I just deleted the PS on Aki, my winter beater Miata today... The Miata power rack is actually slightly quicker than the manual rack. Steering effort is fine except when at a dead stop. As soon as you roll a tiny bit it is fine. An 818 will be lighter on the front tires than a NA Miata (2200 lbs, 50/50 weight dist) I've autocrossed this setup previously and it works great. Looping lines depowering has 5 - 10% more effort than full disassembly and removal of the piston and seal. (on a Miata) The 818 steering response will be dependant on many factors that are not shared with a boosted econobox WRX... so don't worry about it.

[RM1SepEx]

I finally got around to pressing in the front wheel hub and pressing out the rack to finish de-powering it. My donor parts are completely ready and reconditioned....

EXCEPT:

What did you end up using to fill the plugs where the lines were on the steering rack? I don't want to butcher the old lines and crimp them off. I could buy some new fittings and weld them closed. Anyone know of a source for correct metric plugs?

[metalmaker12]

I am done and waiting for kit also, I am getting some other extra stuff soon. I will not need those strikers, I am dismantling a 818 donor this weekend, so I will have em, thank you though.

I would just tack or glue on a copper pipe cap on the the line ports and paint them to match. Thats what I am doing.

[Mechie3]

I'm using the factory fittings with the lines cut out and the ends welded up.

[Erik W. Treves]

pretty sure you want to leave the holes open. ... this is how we depowered the cobra kits for years... I just removed the fittings and lines and let the rack drain...done...did the first cobra that way and the locost miata rack that way. ..ran the cobra for 9 years through the snow and rain with no ill effects.

[RM1SepEx]

Metalmaker... helping disassemble another donor for another kit?

Thanks for the inputs, No reason not to close them up. No pressure or flow from the two on the rack, the center seal is now gone, the piston doesn't displace fluid

The upper control ones need to be closed up to keep crap out of the system, again no pressure... I'll cap em off somehow, just looking for alternatives!

I've left my aluminum LCAs and the front rear aluminum bushing housings clean but not polished... Perhaps I should powder coat them... My rear adjustable lateral inks are powder coated red... I'm not real strong on estetics... :-) thoughts?

[Mechie3]

RM1 is correct, we cut out the center seal, so there's no pressure. Best to seal it up and keep dirt out.

I'm leaving my aluminum as is. Clean, not polished, or otherwise coated.

[metalmaker12]

Yea I am helping a fellow forum 818 guy out for a tear down for his kit. Maybe I will document it since I did not my own.

There may not be any ill effects of something entering the rack, but I just did it for peace of mind. The upper rack ones I tig welded shut, blasted and clear coated to protect and keep stuff out, and I will cap the bottom ones.

If the rears are red and you like the way they look than why not make them all red. I like the polished look myself, but I like the stock aluminum look far better, so they are staying the way they came. Just my taste on that though.

[RM1SepEx]

The rears lateral links came in red, no choice, not sure what I like. The trailing arms are re-done in Eastwood chassis black, as are the uprights/bearing carriers, front and back

I've left the engine case and transaxle in bare aluminum... I'm building a driver not a show car but somewhere you need to find a balance... the engine brackets, oil pan, water tubes, etc... are semi gloss black PC, the valve covers, wrinkle PC, the various re-used painted parts are done in Eastwood semi gloss chassis black... The calipers are red ceramic, the caliper brackets, semi gloss black

I want a PC frame... I assume that the std Factory 5 PC Chassis in semi gloss black...

As a color blind, engineer, all practical, almost no esthetic creativity I'm not sure where to go with it. Red gel coated exterior, perhaps some vinyl accent graphics? Seats in two tone leather?

I need some of VMans creativity!!

[longislandwrx]

I finally got around to pressing in the front wheel hub and pressing out the rack to finish de-powering it. My donor parts are completely ready and reconditioned....

EXCEPT:

What did you end up using to fill the plugs where the lines were on the steering rack? I don't want to butcher the old lines and crimp them off. I could buy some new fittings and weld them closed. Anyone know of a source for correct metric plugs?

you have several options..
welding the plugs solid, and grinding smooth.
if you don't have access to a welder you can also take the existing hose and create a loop. just bend/cut/remove the flare/ put the other fitting on the hose and re flare. like this
0232.jpg

you can use a std npt plug if you have some, just get a close size and add a little epoxy.

a short metric bolt with the right threading would work too... I haven't taken mine apart yet so I haven't put the thread gauge on it yet.

[Mechie3]

I want a PC frame... I assume that the std Factory 5 PC Chassis in semi gloss black...

Don't know what colors they have, but the PC frame is an option on the 818. Standard is not PC.

[RM1SepEx]

understood, I plan on purchasing the optional PC and assume that it is semi gloss black...

[metalmaker12]

RM1, pick a theme you like and just go with it, if it all has a nice flow, it will look cool. I would personally not do two tone seats, but if you like that, its cool, thats what it is about. when I build a car for me, i try to keep it looking stock as I can on the outside, with some nice wheels, but make it go like the wind and it is basically a race car under its sheet metal. If I had to coin it "the race sleeper look" lol. Heres examples, next time I go to wicked Innovations i will take some pics of the race car their building to give you more of an idea. mann_04.jpgmann_02.jpgkwinskii_01.jpgkwinskii_02.jpg

[Samiam1017]

Isn't an Acura type r rack electric? I wonder if they are almost the same size?

[metalmaker12]

Yeah if it is, or a 2009 up honda fit electric power rack which has a even faster ratio of 12.7, this has been mentioned, but is still a good idea

[Racebrewer]

Acura Integra Type R is not electric. Pretty standard hydraulic assist which often gets de-powered. Long thread in the Type R forum on Honda-Tech which might help.

John

[metalmaker12]

As racebrewer pointed out there is no evidence of a electric rack in any year integra. That still does not rule out an electric rack from a 2009 an up honda fit, or other hondas and brands that have a similiar setup.

[wallace18]

I wonder if the Eltra-Steer from the 33 kit could be adapted to the 818, if one thought they had to have P/S. In a car this light I just don't see the need for it. JMO.

[longislandwrx]

My rx7 had manual steering and was never an issue... even with wide sticky tires. Imho power/electric steering just seems like so much work/weight to solve a problem that doesn't exist.

[RM1SepEx]

My rx7 had manual steering and was never an issue... even with wide sticky tires. Imho power/electric steering just seems like so much work/weight to solve a problem that doesn't exist.

agreed... if my 16 year old drives a 91 Miata with a depowered rack (looped with internal piston intact) I can't see issue with the lighter 818. She likes it better for general driving and notes that as soon as you have any movement it is fine... I drove a Fiero for years, manual rack only avail. autocrossed her too, no problems.

Any alternative rack needs to have the same length or it will be very difficult to avoid bump steer issues...

[JeromeS13]

One could always keep the Subaru rack and use an electric pump from an MR2...

[Xusia]

For the ignorant among us, why an electric rack vs. the power rack that Subaru provides?

I plan on de-powering the rack for my kit, so this question is just to help me understand the desire for an electric rack vs. the stock power steering.

[StatGSR]

^ i assume people just want to avoid the long hose runs that will be required with the engine in the back and the steering rack in the front. besides that, i see no reason why the stock PS couldn't be retained if you really wanted PS.

[metalmaker12]

Either a depowered rack, standard ps rack or electric rack, whatever works for each person. But as the thread goes depowering is the way I am going along with almost everyone else.

[FFR-ADV]

Have any of you used a steering quickener? Advantages/Disadvantages?

http://www.landefabrication.com/steering.html

A DIY option:

http://www.landefabrication.com/steering.html

http://www.howeracing.com/c-446-steering-quickener.aspx

Cheers!

[wallace18]

The electra-steer used in the 33 kit is an inline P/S unit with its own controller. You could use any rack or box with it. It was just a thought I had. I was not sure if everyone knew it was an inline deal. JM2C. I am going to use a depowered rack in mine.

[metalmaker12]

That is a good option for sure Wallace, how's the 33, it is looking great man

[wallace18]

It is coming along great. Check out my latests posts for it

[freds]

Valve-Pinion.jpg


I am de-powering my 06 WRX rack, and have it all apart. No problems, having read this thread, and others, numerous times plus the Subaru manual, before starting. (Thanks all).
I am now looking at my valve/pinion assembly, and have been trying to figure out how it works and what two parts need to be welded together to make the link between steering column and rack rigid (ie without the relative movement that adjusts the flow/pressure to one or the other sides of the rack piston).

I came across the attached which says that when there is no pressure from the pump, the two component are "locked" together automatically.....no dissassembly or welding needed if that is the case!!!!

Anyone have any better or more complete information to share?



Control Valve .jpg

[RM1SepEx]

what happens is the two parts rotate slightly vs each other when you turn the wheel, it opens the port that allows the pressurized fluid to flow to the racks piston "helping" you move the rack. it isn't very much but it does add a slight "sloppiness" in the wheels rotation when you turn the wheel. I didn't weld mine yet... I'm not sure how much it will decrease steering accuracy. I do notice it in my daughters depowered rack Miata... It may be an 1/8 inch of the steering wheel rim rotation or so

[freds]

what happens is the two parts rotate slightly vs each other when you turn the wheel, it opens the port that allows the pressurized fluid to flow to the racks piston "helping" you move the rack. it isn't very much but it does add a slight "sloppiness" in the wheels rotation when you turn the wheel. I didn't weld mine yet... I'm not sure how much it will decrease steering accuracy. I do notice it in my daughters depowered rack Miata... It may be an 1/8 inch of the steering wheel rim rotation or so

Thanks...I got that already!

However if you read the second attachment to my post, it specifically says that if there is no pressure from the pump....read on "When oil pressure is not produced due to oil pump breakdown, drive belt damage, or other
cause, torque is directly transmitted from the valve rotor through the spline to the pinion"

As I read that it means there is "direct drive" with no pump pressure .

That is what I am tying to check.

In any case do you have any pictures of a disassembled valve showing the torsion bar and the splines...and what is suggested to be welded in the Subaru part?

I have been unable to find any specific Subaru info on the 06 WRX type.

Thanks for your response anyway, please add more if you have any details.

[Mechie3]

Yes it is direct drive, no it is not locked.

Under normal operation: Torsion bar twists, valve opens, pressure flows to rack, spline never bottoms out as you can't put enough torque on the torsion bar due to the pressure assist.

PS failure operation: Torsion bar twists, valve opens, no flow to rack, torsion bar continues to twist until the splines bottom out.

You still have to rotate to the point that the splines touch. To weld it, you need to remove the bearing. I couldn't do it on my 06. I bought a junk 02 rack to take apart and mess with but I've been too busy getting my Fmod ready for autocross (and racing it last weekend) and machining parts for another fmod for nationals.

[freds]

Yes it is direct drive, no it is not locked.

Under normal operation: Torsion bar twists, valve opens, pressure flows to rack, spline never bottoms out as you can't put enough torque on the torsion bar due to the pressure assist.

PS failure operation: Torsion bar twists, valve opens, no flow to rack, torsion bar continues to twist until the splines bottom out.



You still have to rotate to the point that the splines touch. To weld it, you need to remove the bearing. I couldn't do it on my 06. I bought a junk 02 rack to take apart and mess with but I've been too busy getting my Fmod ready for autocross (and racing it last weekend) and machining parts for another fmod for nationals.

Thanks,
That makes sense. If and when you do get back to your 06 unit I hope you will post pictures of it dissassembled. Meantime I'm putting mine back as it is. As someone else said in this thread "It is easy enough to get back to, if the slight rotation is significant enough"

[metalmaker12]

I will try to get you a pic of what I did on my 02 rack, but on the 06 you have that bearing and valve setup so i am guessing that has to go and than you weld the landing next to the swivel gear to the main shaft of the pinion. I have not depowered a 06, so let me ask around to my tuner friends, but I am pretty sure it is what I said.

[twizzler]

In depowering the rack are you planning on removing the PS pump as well? I haven's found any suitable information on the belt size to use that covers only the crank and alternator

[RM1SepEx]

Check the working on the donor thread, I posted the belt info there and on another thread just last week. I got mine from Summit racing, around $20 delivered.

Any year rack has to have some slight rotation displacement to allow pressurized oil flow and can benefit from welding. I'm not planning on bothering to weld the shafts together on mine. (06 rack)

[metalmaker12]

Yes, many of us have removed the ps and ac pumps. I used a goodyear gatorback 4050272 5pk690 belt, or you can check out what RM1SepEx grabbed on the working on the donor thread

[freds]

I finally understand!...........It just takes time!!!!!

One of the photos from "Project Miatabusa also welded the spool/quill/pinion together:
http://www.motoiq.com/magazine_artic...ring-rack.aspx (thanks Mechie)" shows the splines and the clearance between them clearly.

splines detail.jpg

I don't have a TIG welder and I don't want to hit it with my MIG, so before i go searching for a skilled "outsider", i was trying to think of an alternative.

One thought is:
Cleaning and degreasing well then injecting epoxy steel between the splines. The load on the epoxy will only be compressive...if it were to crumble you are no worse off than "stock". And the crumbs have no where dangerous to go, the oil seal is above the lower bearing. This would eliminate any question of weld heat damage to the metallurgy of the components.

What pitfalls do any of you guys see?

thanks

fred