Rack & Pinion conversion - possible donor candidates

[Matt W]

UPDATE: Looks like all this fess over a rack & pinion might not be so true. I've done quite a bit of research over the past week and in that time have not come up with any 'bad' information about our current steering setup. I went over to the local Border's to check out any chassis/steering books that they may have. I ran across 3 good books. This was my last attempt after talking to a local chassis builder. The shop mainly deals with round-de-round dirt track and some SCCA cars, from what I could tell. He basically said that the only benefit to a rack setup would be to lose ~60lbs. He made several attemps which did sound valid but I just couldn't swallow it. I called BS and moved on to research more myself, which is what brought me to Borders. I read all the books I could find which said the same thing. Cut from what I remember from the chassis engineering book - "All things being equal, the driver feel and input with a rack or gearbox steering setup will be the same. The sole reason you see rack & pinion on so many race cars is for the simple fact of weight savings which is typically around 50 lbs or more if the setup is a manual rack." While another book stated that the reason that a rack setup is more desired is for it's more simplicity setup and less parts to diagnoise and/or fail. Everything I've found so far says that with either setup, if all parts are in OE specs there should be no performance gain in spirited drivings control or feeling. One thing to note, It was mentioned several times in these books that a front steer setup is benefical over the rear setup that we all have. The main reason is because any rear steer setup will cause over-steer as the suspension begins to load in a hard corner where as a front steer will have a slight under-steer and feel more in control. At this point I think I'm done with my work towards the rack setup. Maybe down the road but as I see it, the pro's are called busted on this myth.

 

Thoughts??

 

============================================

OK guys, I'm going to be taking on yet another modification needed to fit my needs. My car is under the knife in the middle of an engine swap. Please check out the swappers section for more information on that. One problem that I've run into is the stock steering arm that runs under the oil pan in the stock configuration. I've taken two trips to a local junk yard. It's a nice place because you walk in, tell them what you want, they give you a ball park price, then you start walking. The place is HUGE with cars dating back to the 40's. Anyway, I was told $50 for any import steering rack that I pull off. So, I came back the next day (yesterday) and started looking over all kinds of cars. I was mainly looking at performance related cars as they will most likely have quick ratio rack & pinion units verse the units you will find on family cars, vans, etc.

 

The best eye-balled fit so far is the units found on the 1985-1989 300ZX and early 80's 280Z cars. I like these units because it places the pinion section close to the drivers side frame rail. The lines run out of the drivers side of the house which is beneficial for room in the engine bay area. I'll go ahead and list possible cadidates. If anyone is in the Hagerstown/Smithsburg MD area feel free to drop me a line and we can go junk yard'n together in hopes of finding a good solution to the wonderful gearbox steering we have.

 

Here are a few cars that I feel could be good candidates for our cars. Although for my setup, I think the 300ZX or 280 power rack will be the best bet.

 

1989 240SX

http://www.mustangmods.com/ims/u/447/527/75666.jpg

 

http://www.mustangmods.com/ims/u/447/527/75667.jpg

 

http://www.mustangmods.com/ims/u/447/527/75668.jpg

 

http://www.mustangmods.com/ims/u/447/527/75672.jpg

 

http://www.mustangmods.com/ims/u/447/527/75673.jpg

 

 

1985 300ZX

http://www.mustangmods.com/ims/u/447/527/75677.jpg

 

http://www.mustangmods.com/ims/u/447/527/75678.jpg

 

http://www.mustangmods.com/ims/u/447/527/75679.jpg

 

 

1987 300ZX

http://www.mustangmods.com/ims/u/447/527/75683.jpg

 

http://www.mustangmods.com/ims/u/447/527/75684.jpg

 

 

1983 280ZX

http://www.mustangmods.com/ims/u/447/527/75693.jpg

 

 

1984 200SX

http://www.mustangmods.com/ims/u/447/527/75696.jpg

 

http://www.mustangmods.com/ims/u/447/527/75697.jpg

 

http://www.mustangmods.com/ims/u/447/527/75698.jpg

 

 

 

BAD Donors

Other cars I looked at

1990 VW Jetta - pinion unit is too close to the engine bay center line

http://www.mustangmods.com/ims/u/447/527/75689.jpg

 

http://www.mustangmods.com/ims/u/447/527/75690.jpg

 

http://www.mustangmods.com/ims/u/447/527/75691.jpg

 

Mid 80's Camaro/Firebird - All wrong...gearbox steering.

 

Late model Firebird - Rack& Pinion but it's front steer

 

BMW Several 80's-90's cars - Rack/Pinion is in the wrong place

 

1987 & 1988 RX-7 - Front steer, all wrong for our need

 

1985-1989 Supra's - All wrong, front steer

 

Honda's (Civic's, Accord, Prelude's) - all wrong, I would assume the same Acura's

 

 

 

That's all for now. I'll be sure to add more information while I research. I'm still looking at the possibility of using one of the Hot-rod style Mustang II racks that is always on eBay for $125. I'll look into that later this week.

 

Thanks

Matt

[lonestarion]

id say go with the 240, dozens of them in jnkyrds here in cali.

relocate the resivoir to the driverside, make shorter lines.

just make sure you grab the K member so you can cut the mounting brakets off an weld the to the starquest K member.

[DJpowerHaus]

I'm not sure how these steering boxes felt when they were new, but they're anything but tight 20 years later. I've seen both worlds and trust me... rack and pinion is MUCH better than the stock setup. Less parts, less friction, more feel to the driver.

 

I've put the 240 stuff on the front. Is it really the ideal setup? I dont think its is. You cannot just make brackets on the stock crossmember. The axis will not line up and you'll get tons of bump steer.

 

What I did was to make adapter plates to bolt the whole 240SX crossmember on. This ended up not working out too well. The lower control arm angles are REALLY bad.

 

If I had to do it again, I'd probably make the crossmember out of a piece of roll cage tubing. This way I could correct for things like having the car VERY low, plus it would be a nice blank slate to build brackets off of for the rack, control arms and engine mounts.

[Matt W]

That's kinda what my thinking is. It just bothers me that I received the same general information from several different independant resources. I know on my last StarQuest (1989 with 40k miles) that I owned well over 10 years ago, the steering felt great compared to this 1988 with over 100k miles.

 

Another concern that I had was if I want to convert to a rack setup, it will need to be about 1" lower than the current center steering arm. That could pose a big problem in itself.

[smog]

All my cars have had sloppy steering compard to any of my cars with a rack, even my honda with 149k has tight steering.

 

Slop is the biggest problem, and rbeuiding a box is stupid expensive. Might as well shave off weight and get a nice steering setup at the same time.

 

As for racks, from what I understand, the 300zxracks have about 15020degrees less angle than a 240 rack, so 240 should be the way to go.

[Matt W]

I take it you mean 15-20 because 15020 would be like a crazy amount to deal with

 

What aspect of the OE design on the Nissan are you referring to anyway....the steering shaft or tie-rods?

 

I do agree that it's crazy expensive to rebuild a box. What I'll probably do with my setup is design the engine/tranny mounts and locations around the gearbox steering setup for now. There is quite a bit of slop in my current setup that I'll address later.

[MainstreaM]

I've said it again and again.

Check the 82-85 Celica or the same years Supra.

 

Kane

[Matt W]

Since I missed that thread, care to explain why?

 

I looked at several toyota's and didn't see anything even close to what we need. I would be surprised if the front end off of a 240sx didn't bolt right up to our cars.

[artinist]

hmm, i posted some research i did in a thread with pics but i can't see to find it at the moment.

 

i also came to similar conclusion. the 200sx, 300zx and 240sx had the best candidates.

 

the toyotas were not good candidates.

[artinist]

here is that thread

 

http://www.starquestclub.com/forums/viewto...sc&start=25

[lonestarion]

well, if the oilpan is in the way you could alway mod that area. bend a peice of sheet metal into a U shape cut that section of the pan out weld in the U shaped peice then work with the rack from their. ther are tricks to rid bumpster, just have to find them. dont imagine it would take long to rid if you worked at it. 1st gen supra aka celica supra; that body style had a rear steer rack as well.

[Matt W]

Hey Art, thanks for the information. When I get some time I would like to buy a complete front suspension off of one of the 240SX's, just need to find the time. Like I said earlier, I would be really surprised if it didn't just bolt up.

 

Lonestarion - I've already whacked as much as I can from the oil pan. I'm currently sitting with around 1/2" between the main support for the crank and the oil pan (inside).

[lonestarion]

have you looked into 1 of those universal racks from jc whitney,summit,jegs? what about 1 of those mustang II front ends

that all the hot rod owners use?

 

thew axis will line up if you insert the tie-rod from the top,

that would keep the tie-rod to rack axis close to zero

[DJpowerHaus]

Hey Art, thanks for the information. When I get some time I would like to buy a complete front suspension off of one of the 240SX's, just need to find the time. Like I said earlier, I would be really surprised if it didn't just bolt up.

 

Lonestarion - I've already whacked as much as I can from the oil pan. I'm currently sitting with around 1/2" between the main support for the crank and the oil pan (inside).

 

What makes you think it'll bolt up? You do know that I have done this right... and posted pictures of it. You shouldnt need to modify the oil pan either. There should be plenty of space between the bellhousing and crossmember.

 

http://projectzerog.com/drifting/images/rackOnRacecar.jpg

Its not perfect, and it wasnt a bolt on affair. I'll probably rework the crossmember to raise it up to correct the extreme control arm angles. Lots of other issues arrise, but for the most part if you're looking for a way to do camber plates, coilovers and big brakes it points you in the right direction.

 

have you looked into 1 of those universal racks from jc whitney,summit,jegs? what about 1 of those mustang II front ends

that all the hot rod owners use?

 

thew axis will line up if you insert the tie-rod from the top,

that would keep the tie-rod to rack axis close to zero

 

Those "universal racks" are not as universal as you'd think. They are a much wider rod than would work with our crossmember/control arm setup.

 

Might help to contact the guys at A1-Driveshaft who also sell rack and pinion setups: http://a1driveshaft.com/rack.html or even Pegasus Auto Racing: http://www.pegasusautoracing.com/group.asp?GroupID=STEERRACK

 

You cant just put the tie rod in from the top. It uses a very specific taper that will only work from the bottom. You might find some way to bore them out and use an appropriate bolt an d heim joint.

[markE]

Why are you looking at mounting the rack in the rear position? Mounting it infront of the crossmember is not to hard. I put a volvo rack on the front of the crossmember using part of the crossmember off the volvo.

next I took the knuckle arms switched sides and turn them over. then it is a mater of changing tie rod ends and hooking up the steering shaft.

Mark

[Richie_Rich]

Mark,

 

Do you have some pictures you can share or better info, like what year and model car, tie rod ends, parts to attach steering column, etc?

 

Thanks,

 

Rich

[ALANFROMPDX]

I have the 240 rack and crossmember.

Cutting the mounts off the 240 rack and fitting them over the starquest rack looks to be the ticket.

If we have sun this weekend i will cut it up and show you how I feel this to be easy as sunday morning.

I will shoot it this weekend and get the pix up.

Any picture anyone would need to see let me know.

 

-Alan

[putz2point6]

tubular k member from mustang, and hack it up to your needs, or completly fabricate one of your own

[quikconq]

just wanting to know, wat ever came of this

alan????

matt????

[lonestarion]

magna/galants are rear steer rack & pinion cars. can this be adapted to work on the starquest or no?

[Jay_S13]

Since I like where this is going, I figured I'd add a little knowledge of what I have to this.

 

There are two different steering racks that the 240sx has. One you're most likely to find in a junkyard is the basic 17.1:1 steering ration one. Comes on all model years, 89-98 are all interchangeable. But there is only a handful of HICAS cars out there that have the 14.7:1 steering ratio. This means basically less turns lock to lock.

 

The Hicas system is a 4 wheel steering system Nissan used in their cars in the late80s / early90s. So only 89-93 fastbacks will have it.

Easiest way to tell if the car you found in junkyard has this or not, is to look at the rear suspension and see if there are tie rods. Tie rods in rear = Hicas = SCORE!!!

 

Hope this helps.

[pure_insanity]

anyone fgound a good suitable, non-power rack. im looking to loose the power steering.