jhalsey Posted November 23, 2011 Share Posted November 23, 2011 I realize that the topic of what manual or power steering rack alternatives exist for 240Z owners has been discussed a lot and I have tried to read as many as I can find but I have a challenge that I would appreciate help with. I have a heavily modified 72 240Z. The car has been seen here a few times over the years in various stages of development. It is now finished except for one fundamental problem: the steering effort is very high and the rebuilt steering racks (2) that i have used have only lasted a few hundred miles each before developing excessive free play on center. The car has a Viper engine, T56, R200 drive train. The reason the steering effort is high is that there is greater than stock weight over the front axle (despite moving the firewall back 4" and the oil pan front lip is right behind the rack) and the front tires are larger than stock (225x18). As new parts to rebuild the steering racks are no longer available from Nissan, the re-builders use various tricks to tighten up these racks (e.g. shot peening the pinion gear). In my application, this results in premature wear and free play due to the higher than stock loads being carried by the rack. These rebuilt racks may be fine for stock applications. I even wrote to the CEO of Nissan outlining the problem with NLA steering racks and repair parts and it constituting a safety issue as these cars get older. Still holding my breath for the reply. So since I cannot locate a new (not rebuilt) OEM 240Z rack, I have to find a suitable rack that will interchange with minimum modifications. I have .2" rear clearance to the oil pan. I have seen mentions of Toyota MR2 and Subaru power racks being installed. I would be happy to fit a power rack if i can find one that is dimensionally similar and does not interfere with the oil pan. I would also consider a manual rack in which case I would also be looking for a slower steering ratio to decrease the effort and also will probably fabricate 1" longer steering knuckles to also reduce steering effort. If anyone has a pair of stock steering knuckles for sale I would like to purchase them so the car does not have to be apart while the knuckles are being fabricated and finish machined. Thanks in advance for any help. Quote Link to comment Share on other sites More sharing options...
blaze73 Posted November 23, 2011 Share Posted November 23, 2011 The rack needs to be from a front steer car so that limits your choices significantly. Other cars with front steer include: Mustang Miata Subaru BMW 3-series RX7 Probably some others? One of the main issues is that the Z is a very narrow car so most racks are too wide, placing the inner tie rod joints too far apart, causing geometry issues (bumpsteer). Quote Link to comment Share on other sites More sharing options...
morbias Posted November 23, 2011 Share Posted November 23, 2011 Can you not use a rear steer rack from a right-hand drive car and just turn it upside down? Quote Link to comment Share on other sites More sharing options...
jhalsey Posted November 23, 2011 Author Share Posted November 23, 2011 The rack needs to be from a front steer car so that limits your choices significantly. Other cars with front steer include: Mustang Miata Subaru BMW 3-series RX7 Probably some others? One of the main issues is that the Z is a very narrow car so most racks are too wide, placing the inner tie rod joints too far apart, causing geometry issues (bumpsteer). Yes, I agree, these are candidates to be investigated. The problem is there seems to be no way to obtain the physical dimensions of these various racks and compare them to the stock Z rack other than placing them side by side on a bench. I was hoping there are some members who have hands on experience with some of these racks in a Z and can shed light on which will fit and work better than others. Quote Link to comment Share on other sites More sharing options...
blaze73 Posted November 24, 2011 Share Posted November 24, 2011 The Subaru rack is the most proven. All the info is here http://forums.hybridz.org/index.php/topic/46504-lt1-and-subaru-rack/ E30 setup was made to work in a 510 here http://forums.hybridz.org/index.php/topic/74875-510-bart-sr20det-powered-wbmw-suspension/ You could alternatively install an electric steering column such as http://www.flamingriver.com/index.php/products/c0018/s0001/FR40105 Other than that, start plundering junkyards with a tape measure. Quote Link to comment Share on other sites More sharing options...
jhalsey Posted November 24, 2011 Author Share Posted November 24, 2011 The Subaru rack is the most proven. All the info is here http://forums.hybridz.org/index.php/topic/46504-lt1-and-subaru-rack/ E30 setup was made to work in a 510 here http://forums.hybridz.org/index.php/topic/74875-510-bart-sr20det-powered-wbmw-suspension/ You could alternatively install an electric steering column such as http://www.flamingriver.com/index.php/products/c0018/s0001/FR40105 Other than that, start plundering junkyards with a tape measure. Not much room under my dash and $6k plus labor for the electric system is not a bargain, plus i would still have the free play in the rack. I will focus on Subaru racks, my shop has a rack rebuilder near by, should be able to compare Z to Ru units and see what the issues are. thanks for the help. Quote Link to comment Share on other sites More sharing options...
jhalsey Posted November 25, 2011 Author Share Posted November 25, 2011 Not much room under my dash and $6k plus labor for the electric system is not a bargain, plus i would still have the free play in the rack. I will focus on Subaru racks, my shop has a rack rebuilder near by, should be able to compare Z to Ru units and see what the issues are. thanks for the help. Here are a couple of pictures of the car. Hood vents were a big project, CNC'd from Al plate. Quote Link to comment Share on other sites More sharing options...
Kpt. Trumm Posted November 29, 2011 Share Posted November 29, 2011 I am standing face to face with the same problem. I'm going to build a new front suspension for 240Z with rod ends. Already have installed 4X BC S13 front coilovers. Now I'm thinking of what to do with steering rack. I have SR20DET engine and power steering pump. I searched but didn't find any answere. Why no one use S13/S14 steering rack? Is there some specific problen that no one has looked that way? It is logical way to go. Sorry for spelling. Not my main language. Quote Link to comment Share on other sites More sharing options...
blaze73 Posted November 29, 2011 Share Posted November 29, 2011 S13/14s are rear steer, the Z is front steer. You would have to essentially swap in a whole S13/14 front suspension for it to work. Quote Link to comment Share on other sites More sharing options...
Kpt. Trumm Posted November 29, 2011 Share Posted November 29, 2011 Jeah but RHD steering rack would work on LHD 240Z Quote Link to comment Share on other sites More sharing options...
Pharaohabq Posted November 29, 2011 Share Posted November 29, 2011 Well I don't know if it's been tried swapping a LHD rack in flipped over for RHD. I don't think that's the main problem here though. It's the weight that the rack is pushing not only from the engine, but from the width of the wide tires. (Awesome swap btw) If I were you I'd try one of the Subi forrester racks since the forester is a lot heavier than the Z, and the swap is well documented. Though I don't know if you're going with power steering or not. One idea is possibly to look at some truck sreering racks, like mid size or small trucks, or possibly a Jeep rack. I don't know how well they'd fit, but they should be heavy enough to handle the added weight. I think my jeep has frame rails that are almost the same width as my Z. I'll have to measure that. Then finding tie rods would be a PITA. I guess the first thing is to just find one that could fit, then begin to mods to make it fit. With a viper engine, I'm sure you're no stranger to mods. Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted November 30, 2011 Administrators Share Posted November 30, 2011 Of production car racks, I like the BMW stuff. They are only a smidge wider (inner joint to inner joint) than an S30 rack, come in a variety of ratios, and have good feel/feedback. I don't care for the way Subaru racks feel. As mentioned, the mid-80's Mustang/T-bird rack is a choice. They come in at least two ratios (the quicker ratio being quite quick), and are slightly wider than an S30. I don't have an opinion on their feel. This is the rack blueovalz used. I'm not sure how much he's documented it here, though. It was a write-up in his book that I bought about 2 century's ago. Now that I think about it, I have one of these floating around the shop that I had intended to use and never got around to it. Quote Link to comment Share on other sites More sharing options...
ckrell Posted January 13, 2012 Share Posted January 13, 2012 Of production car racks, I like the BMW stuff. They are only a smidge wider (inner joint to inner joint) than an S30 rack, come in a variety of ratios, and have good feel/feedback. I don't care for the way Subaru racks feel. As mentioned, the mid-80's Mustang/T-bird rack is a choice. They come in at least two ratios (the quicker ratio being quite quick), and are slightly wider than an S30. I don't have an opinion on their feel. This is the rack blueovalz used. I'm not sure how much he's documented it here, though. It was a write-up in his book that I bought about 2 century's ago. Now that I think about it, I have one of these floating around the shop that I had intended to use and never got around to it. I'm about ready for power rack for my build The BMW sounds good, witch did you use? Any paticular model and year info you can share that you liked? Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted January 14, 2012 Administrators Share Posted January 14, 2012 I'm about ready for power rack for my build The BMW sounds good, witch did you use? Any paticular model and year info you can share that you liked? I haven't installed one in a Z, only a 510... http://forums.hybridz.org/index.php/topic/74875-510-bart-sr20det-powered-wbmw-suspension/ It was a rack from a 3.2 liter E36 M3 ('96+) ZF quotes their rack ratio's in millimeters per revolution, from the on-center position. Here are a few choices... 3.0 liter E36 M3 ('95) - 39mm/rev. It is variable ratio and gets much quicker near the ends of it's travel. 3.2 liter E36 M3 ('96+) - 45.5 mm/rev. Z3 (4cylinder) - 53.5mm/rev. I put one of these in my E30 M3 and loved it. Reduced the lock-to-lock from 3.5 turns down to 2.75 There are several others available and they are externally 'similar' (it's common for people to swap them between BMW models with little effort). Also, from what I've witnessed they typically have a little more total travel than an S30, so you shouldn't loose any turning radius. Here is a picture of a 1995 M3 rack I have here... Quote Link to comment Share on other sites More sharing options...
ckrell Posted January 14, 2012 Share Posted January 14, 2012 That some great info,thanks. Do you know if the 510 and 240z LCA pivoits are close to the same? Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted January 14, 2012 Administrators Share Posted January 14, 2012 Do you know if the 510 and 240z LCA pivoits are close to the same? They are not. The 510 is considerably narrower. It was irrelevant in my case because I used nearly the entire BMW front suspension, including crossmember, and left the geometry fairly close to stock BMW. The BMW racks are a much closer match to the S30 geometry than a 510. Quote Link to comment Share on other sites More sharing options...
ckrell Posted January 14, 2012 Share Posted January 14, 2012 Thats good, I'm making adj LCA's and my new crossmember has LCA povit hole/slots .5" shorter or longer than stock for mockup. Hopefuly that get me in the zone. That rack doesn't happen to be for does it? Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted January 14, 2012 Administrators Share Posted January 14, 2012 That rack doesn't happen to be for does it? I no longer intend to use it, so I would be willing to sell it. $175 shipped. Quote Link to comment Share on other sites More sharing options...
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