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ferret
If anyone has ever wondered about this swap I can now confirm that it is quite simple. I have used a power steering rack in mine simply because my car had manual steering and I wanted power steer. Bear in mind that you will also need to swap to S13 hubs, brakes and struts at the same time. By the way this was done on a right hand drive aus spec car.

To do the swap you will need the following:
Complete S13 steering rack including tie rod ends
LHS rubber rack mount
The lower section of the S13 steering column (below the rubber spacer)
I used the S13 power steering lines and pump in mine, again because they came with the front cut and were laying on the floor. S12 lines and pump may well fit, but I didn't have them here to compare.

I'm going to assume at this point that you already have the front of the car off the ground and the tie rods off the struts.
First, the easy bit. Undo the bolt that holds the lower knuckle of the steering column onto the rack, from memory it's easier to get at this from underneath with the car up on stands, undo the 2 bolts on each side that hold the rack in place and it will now drop down off the crossmember. The steering column may not be very willing to part company with the rack so a bit of persuasion with a hammer and/or heat may be necessary.

Next the fun starts, you can reuse the rubber mount off the rhs of the rack, but will need to fit the S13 rubber to the lhs. The stock S12 bracket and bolts that hold the rack in place can all be reused here, basically reverse the procedure above and you will have the rack in place.
Grab your power steering lines off the floor and slip them up and roughly into place, you will probably need to bend tham a little bit to get a neat fit. Be carefull though as you can kink them fairly easily and then they are good for nothing.

Screw the fittings into the rack before you mount any of the brackets so that you can make sure that the lines are in the right spot. The S13 brackets that hold the lines in place will be nowhere near fitting at the moment, but they can be easily bent to shape. I had to drill a new hole in the rhs bracket, but just bent the other 2 to suit. Took about 10mins with a pair of pliers.
Mount the fuid resoviour on the lhs strut tower, or wherever else suits you, holes will need to be drilled if you are using the S13 part, it's close, but again won't quite fit. Hook up your hoses to this and the pump.

Before trying to fit the tie rods to your shiny new (or in my case very grubby and second hand) S13 hubs, you will need to shorten the steering arms slightly and cut a small amount more thread for the lock nuts. You can probably get away with not extending the thread, but the adjustment will be limited. You will only need to cut about 10mm off to get the right length, run a file over the end of the steering arms hen you are finnished cutting them to remove any burr that may be left. put the tie rods back on and they can now be roughly adjusted and fitted to the hubs.

The only thing left now is the steering column, this will require a bit of specialist work unless you happen to have a machine shop in your back yard. First you will need to remove the lower section of your S12 column, mine was particularly stubborn and required a lot of CRC, heat and a few hits with a big hammer before it came loose.Once removed you can now throw it away. Take the lower section of S13 steering column mentioned earlier ad if you measure it up, you will find that with the small 2 bolt flange cut off the top it is exactly the right length to mate your new steering rack with your existing column.

Take it to a machine shop and get them to cut off the flange and machine a spline on the end to match the existing one. Once this is done you can go home and enjoy your new steering (after filling it with fluid and bleeding it of course).

As you can see it's not the most complex of jobs, and with a bit of preparation could be completed in a day. I hope that this helps out anyone who has been thinking about the swap and like me couldn't get a decent answer as to wheather it was even possible, let alone difficult.

Regards,

Jaimie
seishuku
Couldn't you keep using the S12 hubs, if you use the S12 tierod/rod ends?
ferret
Yes, if you use the S12 tie rods and rod ends you should be able to use the S12 hubs. I don't really see the point of the swap then though, I did the conversion because my car had manual steering and I had all of the power steering parts from my front cut sitting in the shed. Just made more sense to me to use the stuff that I already had rather than buying more parts so that I could convert it to power steering.
YankeeDrifter
Could I then add a S13 quick-rack? Do they make them for S13's?
ferret
Can't say that I've ever heard of an S13 quick rack, but then there's a lot of things that I haven't heard. I believe that the ratio used in the S13 rack is slightly lower than the S12, I would recomend using the S13 speed sensitive pump if you can too.
Fester
That's some good work there Ferret.

I've often wondered about a power steering swap from an S13 (S12 donor cars are pretty hard to find), but I've never felt inclined to pull my car apart to find out if it would fit... I'm not the most mechanically minded person; give me a PCB, a soldering iron, and a handful of SMD components and I'm happy but spanners, meh, that's work :roll:
SHEPPO3930
good job, add some modified tierod ends for more lock and you will be able to get that massive opposite lock happening mid drift, or just in the carpark when u wanna do a tight park :)

i have always thought about power steering, but my S12's manual steering is light and i dont seem to need it, so i havent bothered. please let me know mow much better it is, as the S13's i have driven didnt feel too much different to the S12, only the wheel was lighter, maybe thats a good thing.

good write up, maybe a possible sticky or into the "already answered" section.
Umai Naa
nah, sticky's fine;)

i was gonna do the s13 rack conversion my self, then i was gonna find a s12 pwr/str rack, but i've decided that pwr/str isn't necessary for my needs.

more stuff = more weight = more potentional problems = more $$

i'll probably pull the exisiting rack out and exchange it for a rebuilt one (minus the tie-rods).
Joel07
Man, I don't think I've ever even seen a manual steering S12 here in the states, and from the way you guys talk, almost all of them are manual down under? I'm jealous... ;-)
Umai Naa
our cars got power steering standard from late '85-onwards i think.
hillkill
I just found out that the Us model hicas equiped 240sx has a shorter lock to lock ratio. Just a bit of hopefully usefull knowledge.
gadget1382
Please PIN or Stickey this write up!
RB25sx - SLPR
Had anyone tried converting the entire steering column to an S13?

-Dan
Umai Naa
No, because the mounts are somewhat different.

Besides, why would you want that shitty rubber damper into the equation?
silverarrow27
QUOTE(Umai Naa @ Apr 14 2008, 10:27 AM) *

No, because the mounts are somewhat different.

Besides, why would you want that shitty rubber damper into the equation?


Actually there are metal dampers that are available now to get rid of the rubber.
TE27Levin
ITs ALL a direct swap. You just need to make the lines. I used the stock S12 inners and outers.
bartc_j
im going to sticky this as the info is great, any chance you have any pics with this swap,,,
gadget1382
Swap will be happening starting monday... along with a few other things.
Will get photos and hopefully an easy way of doing it.
Umai Naa
QUOTE(silverarrow27 @ Apr 14 2008, 03:10 PM) *

Actually there are metal dampers that are available now to get rid of the rubber.


No shit, Sherlock.
gadget1382
QUOTE
QUOTE(silverarrow27 @ Apr 14 2008, 03:10 PM)

Actually there are metal dampers that are available now to get rid of the rubber.

QUOTE(Umai Naa @ Apr 15 2008, 10:15 AM) *

No shit, Sherlock.


Unfortunatly that does not help...

I'm trying to come up with a way that will "limit" the amount of customisation required, as the S12 and S13 splines are very different. Welding them together is one way, but if involved in an accident, will possibly leave you pulling the steering wheel out of your chest even with a 4 point harness.

Not to mention you will feel road vibrations directly and strain the flex joints more.

DW i'll document it too cool.gif
RB25sx - SLPR
QUOTE(gadget1382 @ Apr 16 2008, 04:33 AM) *

Unfortunatly that does not help...

I'm trying to come up with a way that will "limit" the amount of customisation required, as the S12 and S13 splines are very different. Welding them together is one way, but if involved in an accident, will possibly leave you pulling the steering wheel out of your chest even with a 4 point harness.

Not to mention you will feel road vibrations directly and strain the flex joints more.

DW i'll document it too cool.gif



X2.

Lots of people die from having their chest compressed by the steering wheel - its dangerous business.. If I can add on element of safety to the car that when I stuff it into a wall - might save my life... Im going to damn well do it..

Also, when you've got an RB25 shoved in the engine bay - downpipe clearances become a bit of a problem and I need a narrower shaft (hold the penile jokes).

-Dan
gadget1382
My method is for the RHD version, but will undoubtebly follow exactly the same path with the same dia steering rod/knuckles.

Only thing i could suggest not knowing the LHD variant, is a modification to the routing of your dump pipe.

As for your shaft? Sensitive issue is it mate? tongue.gif

silverarrow27
QUOTE(Umai Naa @ Apr 15 2008, 10:15 AM) *

No shit, Sherlock.


Don't get anal because you didn't know about it. rolleyes.gif
heatw
you can just cut the s12 one to size, i did that no custom shaft needed, it comes very close to running out of spline but there is jsut enough to be safe
Umai Naa
QUOTE(silverarrow27 @ Apr 16 2008, 06:05 AM) *

Don't get anal because you didn't know about it. rolleyes.gif


Shit, it's not like I didn't have an entire S13 rack and coloumn sitting on my garage floor for six months...

/bullshit.
mcfizzle
Cut it out, guys. Take it to PM's and leave it off the board.

Good info.
gadget1382
QUOTE(heatw @ Apr 16 2008, 06:31 AM) *

you can just cut the s12 one to size, i did that no custom shaft needed, it comes very close to running out of spline but there is jsut enough to be safe


I am still wondering how the hell you managed to do this?

The S12 has the knuckle attached to the housing for the flexable rubber (vibration absorber)

the S13 spline is different to the S12 one so you cannot use just the S12 one... unless you bent the hell out of it to enlarge the hole for the incorrect spline on the S12 knuckle. I guess US LHD version could be vastly different to the Aus RHD version.

Also, the use of the S13 PS lines is required. The routing for this is different and they run in front of the K frame rather than the S12's routing behind it.
gadget1382
Guys... S13 rack is in... now just waiting on the shaft to be securely welded together then it's fill with fluid and take her for a spin biggrin.gif

Though that might have to wait for the trans mount to be completed (my dummy up one was ok to drive... not to use daily nore track it i found out... close but miss-aligned) oh and a driveshaft... they tend to help in the driving process tongue.gif

Photo's and full documentation will be added to this thread shortly and once proven.
mcfizzle
Good to hear!
Prince
what about a s14 rack into a vg s12???? havent heard of it....but its what im planning
gadget1382
Ok, the S13 one bolted pretty much straight in!

Have not had a heap of time, as other projects have come up. But i have photo's (on my phone that need downloading) but other than bending a couple of lines and using the already installed S13 tie rod ends it went in without a hitch.

S14 i've been told is faster again. As another Aussie has installed it, i assume it would take similar modification (very little) to get it to fit.
S-NationS12
Very interested in how this turned out. Personally I dont want the power steering, but is there really a benefit to switching to the S13/S14 rack if you dont use it? Perhaps just for the sake of being able to use newer bushings and quicker ratio?
gadget1382
I can honestly say, it turned out great. Havent had one issue since being installed.

The steering is more responcive, the weight of steering with a gokart sized wheel is perfect, grabbing the car and getting it to full lock is easy and grabbing the car and setting it straight is something i barely think about now.

highly recomend it to anyone who's got S13 front suspension (can do it with out it too using the S12 rack ends) particularly good for drifters and people wanting a stiff accurate responce in the car.
rage
i dont see how people dont want power steering. you guys obviously dont have any grip in the front to make it heavy. ima have to find a hicas rack for some quick steering action
Arro
QUOTE(gadget1382 @ Sep 18 2008, 07:51 PM) *

I can honestly say, it turned out great. Havent had one issue since being installed.

The steering is more responcive, the weight of steering with a gokart sized wheel is perfect, grabbing the car and getting it to full lock is easy and grabbing the car and setting it straight is something i barely think about now.

highly recomend it to anyone who's got S13 front suspension (can do it with out it too using the S12 rack ends) particularly good for drifters and people wanting a stiff accurate responce in the car.


You said you were going to provide some documentation and pictures... consider this my request to see that happen. Might help those of us who are considering doing it.
Umai Naa
QUOTE(rage @ Sep 19 2008, 06:23 AM) *

i dont see how people dont want power steering. you guys obviously dont have any grip in the front to make it heavy. ima have to find a hicas rack for some quick steering action


Not necessarily. My old drift S12 was converted to manual steering, using a non-p/s rack and crossmember. We left the shorter steering arms on (the ones at the base of the struts), which gave us heaps of extra lock.

Yeah, it was heavy at low speeds, like around the pits, and stuff, but out on the track, it was something I never thought about. Our lack of front-end grip, intially, was sorted out by better alignment. Once we dialled some negative camber into it, it had plenty of grip, but the weight of the steering was the same.
S-NationS12
QUOTE(Umai Naa @ Sep 19 2008, 11:34 AM) *

Yeah, it was heavy at low speeds, like around the pits, and stuff, but out on the track, it was something I never thought about. Our lack of front-end grip, intially, was sorted out by better alignment. Once we dialled some negative camber into it, it had plenty of grip, but the weight of the steering was the same.


My S13 is Manual right now, and its the same way, it does kinda suck at lower speeds because of being a bit heavier (nothing like hitting the gym to get in shape for driving a car, lol) but once you hit past 25, its just like power steering. I personally like it better.
Good to hear the S13 rack went in well.
Arro
QUOTE(Umai Naa @ Sep 19 2008, 04:34 AM) *

Not necessarily. My old drift S12 was converted to manual steering, using a non-p/s rack and crossmember. We left the shorter steering arms on (the ones at the base of the struts), which gave us heaps of extra lock.

Yeah, it was heavy at low speeds, like around the pits, and stuff, but out on the track, it was something I never thought about. Our lack of front-end grip, intially, was sorted out by better alignment. Once we dialled some negative camber into it, it had plenty of grip, but the weight of the steering was the same.


Wait lemme see if I understood this, you're saying that there was indeed an S12 manual rack, or that you used a rack from another car (S13?) and put it in the S12. I'm still confused on this.
Umai Naa
It was an S12 manual rack, and manual rack-specific crossmember. They're quite common in Australia, as power-steering was an option. Very few payed the extra coin to have it.
Arro
Hmm what are the odds one of your AUS12 brethren would be willing to export such a thing to the US?
IggyEGuana
RHD.....
Arro
FAWK.... omg I feel like an idiot, I COMPLETELY FORGOT THAT sweatingbullets.gif
Umai Naa
lol.gif

You're showing some weakness...

tongue.gif
IggyEGuana
Not to say that its impossible to flip the rack over. Where the rack is held down the passenger side is round but the drivers has a peaked shape to it that prevents the rack from rotating front to back. Figure that small issue out and thi should actually be doable. The one big question is if you flip the rack does the steering go backwards???
S-NationS12
screw it, just go RHD Dash and everything...JDM PIMPIN..W/ AN AMERICAN TRUCK ENGINE (which I love dearly) haha
Arro
uhhhh, no let's not go riceboy RHD in an LHD car rolleyes.gif We're not Honda Civic tunerz tongue.gif
IggyEGuana
flippin the rack would make it steer backwards. depending on how its internals are constructed you could drill out the bottom of the part of the rack where the steering shaft goes in. Extend the shaft out the bottom and use it upside down. Obviously more to it than that and sounding like a lot more fab that its worth.. if even possible at all. Much easier to just cut the lines on our power racks, remove the now unneeded power steering crap, and call it a day. Unlessss... Sterlings Sentra/Stanza setup?
Umai Naa
So I assume manual steering was definately not available on USDM S12s?
forivadel
manual steering was only available in '84 in the US. i think they only came in certain xe models (for those who opt out). so all turbos came with power steering. i think theres one person who was on the boards before that had it. manual rack is a rare species indeed.

wouldn't we be able to convert power steering to manual like they do on here?
http://www.flyinmiata.com/tech/depower.php?x=1

edited for bad grammar.
IggyEGuana
QUOTE(forivadel @ Sep 30 2008, 04:17 AM) *

wouldn't we be able to convert power steering to manual like they do on here?
http://www.flyinmiata.com/tech/depower.php?x=1


Yup thats what I just said

QUOTE(IggyEGuana @ Sep 29 2008, 07:51 PM) *

Much easier to just cut the lines on our power racks, remove the now unneeded power steering crap, and call it a day.


Never heard of any US S12s havin manual racks. Will have to keep an eye out for base model 84s.
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