280ZX- Converting to Power Rack and Pinion

[Mr. Tyler]

I have a 1979 280zx with the power reciprocating ball steering box. Also, I have tokico lowered springs, tokico shocks (adjustable on front), eibach swaybars, bump steer spacers, adjustable eccentric front control arm busings, and techno toy tuning adjustable tension compression rods.

Here's a little info....

S30? manual rack and pinion is 2.7 turns lock to lock

79-81 power reciprocating ball steering box is 2.7 turns (16.3:1)

82-83 power rack and pinion steering is 3.2 turns (17.8:1)

79-83 manual rack and pinion steering is 3.5 turns (19.6:1)

Rack and pinion is the preferred choice for performance cars and racing, mainly because it offers better feedback when compared to steering boxes. Also, I believe that it is a little lighter and simpler and the unit is mounted lower on the chassis. I've read here and/or on zdriver that people think that the power rack and pinion units Nissan offered for the 280zx are junk and/or are too loose and/or sloppy.

First I want to distinguish between slop and lower ratio steering. Slop can come from any steering joints, couplers, bushings, rod ends, worn rack/box teeth/gears, etc. while a car with a lower steering ratio may just feel sloppy because it takes more turning of the steering wheel to get the tires to turn the same amount as a car with a higher steering ratio. I'm not exactly sure what the posts I read were referring to. The slop I'm talking about is like the extra play you feel in the wheel, ie. go drive an old truck....if you just made a lane change you'll have to move the wheel 15 degrees back before the wheels even start to straighten back out. That being said, what are you guys with power r+p experiencing?- please give details; what year car, tie-rods good and tight, steering shaft coupler good and tight, good alignment, etc.

Jeff Winter with Rallye/Sport has done some work for me and has been a great resource throughout the years, so I gave him a call. If you don't know him, he has been building successful race cars out of older Z's and 510's with over 30 years of experience and recently built up a 280ZX racer. I'm going to post about 280ZX rear suspension mods with his take on them and some links to his bragging rights. Anyway, he hadn't heard or at least couldn't comment on the 280ZX power racks being junk. The 280ZX he built had a power rack and pinion with the power removed. He said that steering ratio and power assistance is really all about driver preference. He also recommended I get a used unit from the junkyard or wherever and not to spend the money on a remanufactured unit....just flush it out good with p/s fluid. For me, I like harder steering effort and higher ratio's on the track (I have a really small Grant steering wheel), but I don't want to sacrifice drivability on the street, so unless my mind gets changed from replies to this post, I'll be going to Nissan's 17.8:1 280ZX power rack unit.

If you have something to add please be detailed with your reply.

[BluDestiny]

You've been up to a lot Mr. Tyler...good stuff

[woldson]

Although I'm not a racer, I've need had a problem with my ZX's steering being nothing but crisp.

[Mr. Tyler]

Woldson, I saw in your profile that you have an '83. Is that with power or manual R&P?

[woldson]

Both my 82 and 83 that were drivable that I've owned, were power.

 

When I get the car in more of a race condition, I will more then likely "bling" it some in order to keep the engine bay, ummm, cool looking and still maintain the convenience of power steering.

[hunterzed]

I own 3 280zx's. 1 x 1980 (reciprocating ball) and 2 x 1982 (power rack and pinion). One of the later cars is off the road for a full rebuild but I have recently driven both the other cars hence can do a back to back comparison. I'm not a professional driver by any means and both of the running cars have not been freshened in the suspension for a few years. I bought all 3 cars around September last year and both running cars were tram-lining over undulations in the road surface and would wander on a straight section of road as well as being twitchy and unpredictable in the corners. Definately not like you'd expect from these cars. All I did to fix the problem was to correctly adjust the front wheel bearing pre-load and now they both drive and handle beautifully. I didn't adjust either car very much to get a big change in attitude through the steering. I checked that the rest of the steering was in good order as well. I don't notice too much difference between the two types of steering for the type of driving that I do which is as a daily driver on the road but I would say, that the rack and pinion seems to give a more confident feel through the steering wheel. This of course could be as much to do with the suspension in each car which is not identical as it has different brands of shocks but still have factory springs in each. So the test really is inconclusive unless I spend the time to change suspension on each car to get a better comparison. Not likely to happen though.

 

If you like I can get some dimensions of the moving parts like the diameter of the main shaft and tie rod ends etc so you can compare it to the earlier S30 racks or to other racks. I won't be able to do this until I get home on Tuesday.

[ken280zx]

I have a 81 with "ball " steering and I'm converting to 83 R&P mainly due to the fact that when I'm cornering there is a little "catch" that drines me crazy. Plus I belive R&P is more responive. Ken

[Michael Bowen]

I had an 80 ball that I replaced with a R&P to clear a turbo engine.

 

In short, the ball's are tougher and can take more weight than R&P's for a given amount of turning ratio...That is why you see them used on trucks while R&P's are only on cars. Anyway, There isn't a big difference. The ball seemed to have a tighter overall ratio and was smoother/more comfortable, but the R&P had a better on center feel and road feel. Most probably won't be able to tell a difference, and it's not worth changing one for another unless you have a good reason too. (Clearing a turbo, for example) This swap also requires replacing the front cross member from a car that had R&P.

Edited April 6, 2010 by Michael Bowen

[ArchetypeDatsun]

I recently ran into the problem of ball steering when swapping in the L28ET stupid power steering box was in the way of the wastegates accuator and my 83 donors R+P was damaged due to the wheels falling off so I will be swapping to R+P soon.

[kvansic162]

I have swaped to the R&P system. I used a 83 cross member and rack. I had to grind the steering shaft at the joints a little bit because it would bind. The car has a lot of under-steer.Droped almost 100 pounds geeting rid of the gearbox and links.The rack is a semi-manual rack. I am running it with out power steering. A little hard to turn at slower speeds but on the highway it is excellent. I just purchased a full manual rack and pinion ,with cross member and shaft( which is the longest shaft) for the early 79ZX. I plan on installing it later this year in an effort to get rid of the under-steer. I will probably install a camber kit and a caster kit to also help dure the under-steer condition. I am a manager of a Firestone store so I have an alignment rack at my dispossal.

[Jared]

I think most people's slop is just worn components. My 83 with ps is very tight and responsive now after replacing everything that was loose and badly worn in the front end. Both outer tie rods, rack bushings, tension rod bushings, ball joints, and repacked the wheel bearings. With these cars you really have to expect things like this to be worn.