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I’ve seen a number of posts about using a 356 box on our cars (I have a new VMC). Some say they succeeded but never really said what was involved. What has to be changed or adapted. In know the box is more but In considering it. What intrigues me most is the progressive ratio, if that’s the right term. It also is more durable, which is a plus. I don’t trust the VW box to be honest.

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Sometimes, Jason, but the boxes are not the same on the later 356.

https://porsche356registry.org...amp;module_id=546086

I personally don't have any experience with the ZF box used on Porsches, but some people really like them.

Having said that, the brand new TRW VW boxes are junk. It's definitely better to get a rebuilt older German box, or a good older box and properly adjust it.

The other things that can help are a REALLY tight Pitman arm nut(even 1/16th of a turn can be night-and-day different), a proper German rag joint, all good and tight front end components(including properly adjusted wheel bearings), a good condition steering stabilizer and a good alignment(proper caster is important).

I'm happy with my beam setup and steering box. It's as tight as they can possibly be, maybe 1/4" of play(I think 3/4" is deemed "adjusted" in the Bentley) in the steering wheel.

I did purchase the VW Polo rack, but decided to sell it. The juice wasn't worth the squeeze on a Vintage Motorcars Spyder that was finished. I just didn't want to re-do the firewall on a finished car.

I agree that the Polo rack and pinion is the way forward, especially on Speedsters as it's almost an easy bolt-on.

Last edited by DannyP
@DannyP posted:

I agree that the Polo rack and pinion is the way forward, especially on Speedsters as it's almost an easy bolt-on.

Randy - listen to Danny. This setup is what you want.

CSP sells one commercially, but there's a guy in some Nordic nation (Finland?) who does a very nice kit. @DannyP - want to help @Teammccalla with the contact information?

Last edited by Stan Galat

Sounds interesting. I will see my mech on Monday. I just wonder if we are trying to replicate a 356, which people rave about for steering feel, why we wouldn’t use a ZF?

I am taking it in because I have certain limits on what I’m willing to do myself, and I still do work for a living. Installing a different steering system is across the line both on time and difficulty. Doing a straight swap for a VW unit I’d be willing to do except the space under there is pretty damn cramped and I do repairs as a hobby. Those that aren’t fun or easy probably go to the pro.  For example the 964 clutch slave cylinder I am putting off - messy and no fun - goes to my Porsche guy.

My present problem on the Speedster is that some bonehead adjusted my VW box too tight. I turned the wheel and popped the threads on the steering box cover. Stupid mechanic (three fingers point toward me). Dohhhh. I hate it when I do stupid things!

So it’s easy enough to get the cover bolts off, but the adjuster won’t thread through the stripped cover.  Thus, I can’t get the cover off. That’s what sent me down the rabbit hole of looking at steering upgrades. I wish we had a plate to access the top more easily. I might be able to force the adjuster through the cover, but no such luck. The mech will have to disassemble the front partially to pull the box, and either force the cover off or replace the box entirely. If he can get the cover off, we could put a replacement aluminum one on, but then the labor is already spent to upgrade if I want to go that way.

@Stan Galat, good advice as usual.

@DannyP, I will contact Alex and find out what’s available.

Last edited by Teammccalla
@Teammccalla posted:

Sounds interesting. I will see my mech on Monday.

Cool.

Just keep in mind that this is fairly new and "out there". Your mechanic may not have ever seen or heard of it. Here's a link to the CDP setup.

It's unfamiliar looking and seems kind of kludgy until you realize how much thought went into it. The advantage is that the tie-rods are equal length and the bump-steer that is so common with most other (non-center steer) racks. The steering column can stay in the same position.

@Michael McKelvey is the only guy on this board who has installed one. I have a Golf rack on my car - this is better.

I'd choose this over any worm-gear arrangement, but that's just me. Porsche moved to a rack and pinion setup as soon as they got rid of the beam front suspension. 911 steering is lightyears ahead of 356 steering, ZF box or not.

@El Frazoo posted:

So the guy Alex's kit and the CSP thing? -- the same thing, just different prices?  Or different in fact?.  As I look to improve things, an R&P steering unit would be a big improvement.  But would it fit on my JPS hybrid frame works?  Hmmm ...

They both use the Polo rack, but the brackets are proprietary.  The CSP/Kerscher  kit does include the u-joint to connect the rack to the steering column, which, with Alex’s kit, you are left to your own devices.

@LI-Rick posted:

They both use the Polo rack, but the brackets are proprietary. The CSP/Kerscher  kit does include the u-joint to connect the rack to the steering column, which, with Alex’s kit, you are left to your own devices.

... making the CSP/Kerscher kit the way to go for most folks, probably.

The Euro is particularly weak right now, making it almost on par with the USD.

Last edited by Stan Galat

The 356 ZF steering box has been popular in years past with the off-road crowd; with it's larger components it's stands up longer to the beating high speed desert driving inflicts upon it.  It's basic design is the same as the VW so (for a Speedster) it isn't really much of a 'driving' upgrade.  If you really think that 356 parts will make your fiberglass re-creation more 'Porsche-like' and can find 1 at a reasonable price (no mean feat these days!), then go for it, but remember most people (including us) won't care (or even know the difference) and to a lot of P owners (who really aren't car guys and can't appreciate our 'tributes') it won't matter.  Our plastic abortions don't have the proper vin #, will never be part of the fold, and with them that's the end of the discussion.  Build your Speedster to please you- that's what really matters.

A worthwhile upgrade would be the rack & pinion set up mentioned above.

Last edited by ALB

I think these particular new guys are just looking to improve the ride/drive/interface, not bolt a bunch of 356 parts on to make it more "Porsche-like".

I've worked on every one of these things, almost as much as the engine itself. Vague steering, choppy ride, weird front end feel, tail-happy rear, sloppy shifting - these are the things they're trying to improve, and I wish them luck.

The underlying platform is bad enough that many, many things can improve the "touch-points", where the driver interfaces with the car. Better steering and shifting are probably at the top of anybody's list, followed closely by doing something about the front end.

After the shifter, the first thing I'd do is change the shocks and bolt on a CSP Polo rack set-up.

Last edited by Stan Galat

Yup. I'm a fan of the Koni adjustable shocks for the front. I was lucky enough to get a 1970s to 1980s NOS non-gas set from Greg.

They'd been sitting on a shelf in his shop for forever. They were so old that I had to source the OE shock extensions/dust cover/bumper arrangement that threads on top. They were scarred and scratched from rolling around, so I painted them and found stickers on ebay. The Koni folks told me that Krylon orange was a color match, and it certainly is.

I have them on full soft. I could go one click up(of 5) but I really like the ride. It's firm and sharp without being too harsh.

@Teammccalla wrote- "I just wonder if we are trying to replicate a 356, which people rave about for steering feel, why we wouldn’t use a ZF?"

@Stan Galat wrote- "I think these particular new guys are just looking to improve the ride/drive/interface, not bolt a bunch of 356 parts on to make it more "Porsche-like"."

I was only pointing out the direction (and the futility of it) some guys take.  If that's not the case and I'm off base, then ignore me and carry on.  Teamcalla, if you actually do install a ZF box, please report back your thoughts/observations, as I (and I'm sure everyone else here) would love to hear what you think!  Al

@ALB  Plastic abortion, huh?  I prefer “plastic fantastic”.

To update the thread, my plan is to get the box fixed or replaced with fake VW parts because that’s all that’s available.  I’m not thrilled.  I’d prefer to put a correct German rebuild in to tide me over until I make the jump and get R&P.  That is something I definitely want to do, but my goal is to get it drivable while the rain is still at bay.

I do use Porsche parts when possible, even when they are invisible to the slack-jawed kids.  German-made Porsche parts are good stuff.  

BTW, my Porsche mech politely expressed that I might get more experienced service at the local VW shop (which I really don’t prefer, having used them for my splitty bus for too many years).  I will work on welding in a real 356 VIN so that my little plastic joy will get more respect, and confuse the h&ck out of the Porsche crowd.  Meanwhile, I’ll still take my Porsche to him, but not my lowly VW.

Here is the fine point on the Porsche versus replica issue for me.  I don’t want a 65-year-old Porsche.  I’ve had one that was from the ‘60s and that is NOT what I want.  I want a NEW 65-year-old Porsche, with modern power, disk brakes and R&P steering.  I hear that Emory and Canepa make them, but I’m just not quite ready to pony up the expense.  For these reasons, I own a VW replica.

Last edited by Teammccalla

Well the value equation is different for everybody and so is the pocketbook and what is good for one or reasonable is excessive for the other and the argument goes on but most people that are Porsche aficionados are proud enough to feel. They are in an elite class by what they own and will gladly tell you trying to put you in your place that you are not driving real P car … they think we’re trying to pretend that we love their cars. We like the shape, but not the 60 year-old technology no matter how restored it is…

We have a big tent here and going to Carlisle you meet a lot of people that have various Builds and Quality …. they’re enjoying their car as you’re enjoying yours. It’s all good.  

God knows there are so many cars that are made of plastic that people love, Corvettes, etc.

Our cars are not Porsches, although they look like a famous old one.  And i'm really cool with that. I had two steel coupes  (with various amounts of actual steel plus the kind that comes bound with oxygen) back in the day, and my "new" Speedster, despite being a JPS that took and still takes some sorting out, is preferred. Its a VW.  So what?

Stan mentions the man-machine interface (touch points) as #1 on the priority list, and he's spot-on. My first address on that score was the shifter which as supplied was a basic VW "egg on a coat hanger" thing that was so sloppy that ... well you all know how that goes.  R&P steering and different shocks (which do play in to the aforementioned interface) are high on the list.  I see a lot of praise here for Koni shocks, and so will keep a close ear open for info on what would work better than whatever i have now.  I do not know what I have now, as they are just white --??--.  I'm betting I could do better.   My car (2332 mill) handles pretty well, has large anti-sway bars, IRS. What Koni units would work?  Open to suggestions.

R&P: CSP website shows the parts and does indicate that the steering column needs to be modified and welded.  And how their unit would actually fit within the frame of my JPS is a good question with no answer so far.  More research . . .

I could try that. I can tell you that when my car was built by JPS in No. Hollywood, they had two frame options: basic pan, and a purpose-built tube frame plus some pan parts -- a hybrid.  I have the latter.  I'm not a good enough expert on VW mechanicals to know what about the front geometry was replaced up front.  Probably nothing important wrt the front suspension.  Maybe the question is simple: if the VW steering box and tie rods fit and work (they do) then this R&P upgrade will work too. OTOH, I can tell you that there is a lot stuff clamped to the torsion bar tubes that has to do with the tube frame structure.  I'll give picture taking a go. Its pretty tough to capture all of that black painted stuff. We'll see. Txs for the interest.

Yeah, I was wondering that, too.  I have a TRW steering box that has been adjusted pretty close (Per the Bentley manual) to eliminate as much play as possible (for a steering box).  If I'm going to go to the effort of getting someone else's R&P design to fit my car and get it de-bugged, I would really expect a huge handling improvement.

Otherwise, I'm happy with what I've already got, which seems totally acceptable for a car that's never going to see the track again.

Mike, yes the true question: juice vs squeeze??  That would be the essence here.  I am not necessarily dissing the VW steering gear unit per se' as it does seem to be operating as designed, but I do not like the lock-to-lock required, thinking the R&P would offer a much quicker response.  So its not really how tight and precise the mechanical lash-up is, but rather looking to  improve the steering ratio. Another question: does this unit offer a proper stop for the steering so that the tires do not interfere with the torsion  bar, trailing arm knuckles?  I know about this because the VW pitman arm is built to have  adjustable mechanical stops left and right, which adjuster was omitted from my build, and nearly caused a full blow out of the right front tire before I inadvertently saw what was going on.

It is really hard to say because there were many months between driving with the old steering box and driving with the R&P.

It would be nice to be able to drive a Speedster with the steering box and then jump out of it and drive my Speedster with the R&P.

For most people, the juice may not be worth the squeeze.

I probably do a lot of things to my Speedster where the juice isn't worth the squeeze.

It does feel direct with no play.  I do have an issue with the Super Beetle bushing.  When I bought it I was sent 2.  One fit the steering shaft tighter than the other. I installed the tight one and maybe should have installed the looser one. Right now the steering wheel doesn't return to the center by itself.  I spent $70 to have the bushing turned down a bit to fit the tube so it isn't an easy swap. If it doesn't free up by itself maybe I will pull the shaft and open up the bush a bit.

There are no stops to keep the tires from rubbing.  It the only time I notice rubbing is when I pull out of the garage.

Last edited by Michael McKelvey
@El Frazoo posted:

Mike, yes the true question: juice vs squeeze??  That would be the essence here.  I am not necessarily dissing the VW steering gear unit per se' as it does seem to be operating as designed, but I do not like the lock-to-lock required, thinking the R&P would offer a much quicker response.  So its not really how tight and precise the mechanical lash-up is, but rather looking to  improve the steering ratio. Another question: does this unit offer a proper stop for the steering so that the tires do not interfere with the torsion  bar, trailing arm knuckles?  I know about this because the VW pitman arm is built to have  adjustable mechanical stops left and right, which adjuster was omitted from my build, and nearly caused a full blow out of the right front tire before I inadvertently saw what was going on.

Well one way to reduce the lock to lock or at least the feeling of it is to install a 420mm Banjo or VDM wheel and you will feel much more direct ability to steer the car. just saying.

RE: Steering stops

Michael, a couple of L brackets on the rack bracket could be welded in. Weld a nut on each, and with a bolt and jam nut would be adjustable. I saw one of these "Alex" rack kits with stops added to it, maybe on thesamba.

Kelly, the steering stops are most probably on your beam already(sans bolts and jam nuts). You need to add a couple 8mm x 1.25 bolts and a couple nuts to lock the stop bolts where you want them. If the beam was powdercoated(most are) then a tap should be run through the stop threads(#11 in pic).

Balljointbeam

The stop bolts hit two spots on the pitman arm, look at yours. If your beam doesn't have any stops, it can be added:

https://limebug.com/product/t1...box-beam-axle-black/

Also Kelly, if you're happy with the feel, then don't bother with the rack. The rack is only going to give you the same ratio as the steering box(I'm pretty sure they are similar, but don't know numbers). My steering is about 2.5 turns lock-to-lock.

There is a quick steer kit that lengthens the pitman arm about an inch and takes almost a full turn out of the lock-to-lock travel(which will increase your steering effort quite a bit!). It slightly lessens the Ackerman(look it up) and is for "off-road use only"(like everything else for our cars). So say you end up with 1.5 to 1.75 turns total, you'll end up with almost a half-turn less per side. Could be what you want?

There are two different ones, 58-68, and 69-77. Tie rod ends have bigger ends through the pitman arm for the later years. Here's a link to the later one:

https://www2.cip1.com/c13-22-2824/

Ray's suggestion of a bigger diameter wheel will only do one good thing, lessen the steering effort(maybe increase feel a tiny bit?). If that's what you're looking for, sure. The larger diameter wheel will actually LENGTHEN the amount of steering wheel movement(vs. smaller wheel) to achieve the same angle of road wheel movement(This is simple math. Trig, but still simple).

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Last edited by DannyP
@El Frazoo posted:

Mike: txs for the first hand unadulterated driving impression and experience.  Much appreciated.  Have you recovered from the Tour d'Blue troubles?

Hello Kelly you have Mikes mixed up but no worries..we all look alike. My steering is all set and I picked up an Aluma car trailer so my tow bar days are in the review mirror.

I think my safety chain some how jammed the pitman arm which caused all my problems.

Looking forward to next year and this R&P discussion has got me thinking as well.

Michael (MikelB)

I did have to rework my horn wiring.  For some reason, the last time I drove my Speedster the horn decided to blow continuously. I had to pull the fuse.

That’s what you get for tooting your own horn.  Just kidding.

@DannyP Danny is right on the geometry but the bigness of the wheel makes it feel so much more effective at pointing the steering and hence the car  or at least gives you so much less effort that it feels to me more of a complete original feel for the car.  

If you think about what the vintage stick shift does for the car…. it is not just about period correct it is the interface of a 50’s vehicle.  

Honestly to quote a friend of mine, "It is amazing to me how significant a difference this shifter makes. "

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