ZF 4HP22

Great news Warren, you'll have to post a video at some point if you're able :D
I now have my two boxes, one hp22 and one hp24. The cleanup has started and then I'll be onto dismantling and rebuilding the custom box!
I have also ordered my new shifter (B&M console quicksilver which has 123DNRP detents and ratchet manual shifting) so it's only a matter of time and work now :LOL:
Are you keeping a beady eye on your new fuel consumption?
Jim
 
Hi Warren,

Glad to hear that you've obtained overdrive now. Sounds like an excellent result, dropping from 3200 rpm or so down to 2200rpm for 100kph running. If you're already running at 2600rpm for 100kph in 3rd like my Rover and others locally, then a drop like that will see in the region of 1600rpm for 100kph.

Ron.
 
Thank you all, gentlemen. It was a big relief to sort the 4th gear problem out. There's been quite a bit going on behind the scenes to get to the bottom of the problem, and at one point last week it was looking like there might be something wrong in the F-clutch assembly, which would entail dropping the box out again. I was too depressed at the prospect to post on the subject, but with the problem found and the box operating correctly I'm over the moon!

I will attempt to post a video at some point, but I'm not sure how well it will convey the sense of quietness that pervades the car when overdrive kicks in. At a steady 3200 rpm the V8 sounds busy; losing 1000rpm or so the noise just drops away and the car suddenly seems relaxed and effortless.

I've been pushing my luck driving a non-legal vehicle around, so you'll all have to wait for more information on fuel consumption, etc. I've emailed the LVC man to book an inspection, which is likely to be a couple of weeks away, so I'm going to park Brown Rover up until that's done. It's very tempting to drive around, but I've used up all available Rover funds for the time being (and then some), and I don't need several hundred dollars in fines added to the cost of the conversion. In the meantime I will start piecing together some more posts for the sticky thread.

Bruiser's Dad is right, the turnaround has been remarkably swift (for me). However I was motivated to get cracking by the fact that, when the BW blew, I had only just got Brown Rover back on the road after an extended layoff and was looking forward to a good long period of Rovery motoring enjoyment before contemplating more work like the ZF conversion. That Good Friday roadside calamity left me so pissed off that there were two options: a Rover burning party; or a headlong plunge into the conversion. Of course there are several people who have been essential to the process, but here on the Forum I'd like to take the opportunity to thank Andy (eightofthem), without whose assistance I truly would never have got this far. He has donated a lot of time and effort to providing me with information and advice, and I hope to come upon a better means of thanking him than just a few words on the Forum.
 
Warren,
Excellent news, I haven't tried mine yet, still things to do.
Nearly ready for the paint shop.

Glad that you have proven the benefits of the ZF box.
Got me all fired up again...... :D

Jim.
 
I can blather on here all I like, Jim, but the proof of the pudding is in the drive. My motorway tests revealed a remarkable difference, and I'm sure ghce will agree (he was along for the ride). As I've said above, an easy comparison is made by simply snicking the ZF back to "3". At 100kph the car is now a totally different cruising proposition.

As soon as I've achieved the required paperwork, I'm planning an open road expedition to Chertsey, about 45 minutes south of Christchurch, a little town in which there is a particularly good secondhand bookshop (I'm a book freak - when I'm not working on Brown Rover I'm otherwise ignoring my family by indulging in the craft of bookbinding). It's a straight, flat trip which presents the perfect opportunity to stretch the car's new longer legs and see how it fares. That'll be a good time to shoot a video, too.
 
I can concur completely with Warren on this, the difference is remarkable, I particularly like the affect of being in 4th at city speeds of 30 MPH, still plenty of torque at that lower RPM and if you accelerate briskly it will kick down in a more appropriate manner than the 65 I am used to.

One further aspect of the ZF that needs more investigation is the 3rd gear lock up option, my understanding is that some do and some don't. Initially I had been led to believe that only the electric boxes had this option but now I don't know. Consultation with a ZF box expert is required to answer this.

My opinion of electric versus mechanical was gained via one such ZF box specialist who also disliked the 3rd gear lockup something which to me is at odds or counter intuitive to common sense, I can well understand how a 4 cylinder engine might struggle especially being at 3rd gear speed in a city and that coupled with low torque low capacity engines could be a bit detrimental to fast acceleration being well off the torque curve.

Graeme
 
And as you know, Graeme, there is a bit of fettling still to be done. At this point I'd better tip the others off that I'm temporarily running the BMW valve body until I sort the still undiagnosed problem with the LR body. The mismatch between the BMW body, the LR governor and the LR torque converter, along with the TV cable adjusted for the LR body, means I've presently got OK-but-not-ideal shifting, and TC lockup isn't kicking in as it will do when I've reinstalled the LR body. But even so, I'm absolutely delighted with the improvement.

The third gear lockup was alluded to by Nigel, but further information is required. Eightofthem? Meanwhile I can confirm that 4th gear kicks in nicely at around town speeds, and the engine loses around 500rpm compared with 1:1 3rd. A gentle prod re-engages 3rd, meaning that performance isn't noticeably affected, and things will improve further once I've installed the correct valve body.

For those who don't like the idea of having to buy two gearboxes to make one, I can assure you that having that second set of everything at hand is enormously useful!
 
Really pleased to hear of the results of your efforts, Warren. Inspiring for all of us!

The cruising should improve yet again once you have the LR valve body sorted and can get lock up on 4th. I'm pretty sure this should also give you lock up on third - but don't hold me to that! Having driven a different ZF with lock up on third and top, I'd say it is worthwhile. Almost all town driving should be in lock up third, only very slow trickling or getting away from rest should trigger 1st and 2nd.

So before your inspection, there's the LR valve block to sort and have you go the speedo working yet?

Chris
 
Congratulations Warren, I can only imagine the satisfaction of having a Rover V8 running successfully with a modern auto box in it!

I might have missed details on ZF configurations in different applications, but from memory Land Rovers, as do BMW 5s and 7s, usually have a FIFTH and then lockup in 'D'? I have a 5hp18 in my 3 series TDS with 417 000 kms on it. On minimal throttle, third engages at 35, 4th at 53, and 5th around 85. Lockup happens from 115 and I had the opportunity to run a high speed test on the Autobahn last year. At 210 kmh the needle read 3350 rpm, and I get a little frightened at the theoretical top speed...
 
5HP = 5 gears, Tor, 4HP =4. You must be thinking of post-millennial Land Rovers. Where gears are concerned, three certainly ain't a crowd, and I'm sure 5 could be better than 4. But to keep things simple, we're restricted to what went behind the Rover V8 in production vehicles, and that means the 4HP22 from the Range Rover Classic right up to the last Discovery 2s. This is the same gearbox that went in all manner of 1980s and 1990s BMWs from 3-series to 7-series. In my opinion the easiest box to deal with is the Discovery Series 1, since it has hydraulic control and all the right bits to mate up to the P6 engine. Then all you need is the BMW/Jag rear end. I will be posting more in the sticky thread as time goes by, but forgive me if I'm a bit ZFed out right now and it takes me a while to work up the enthusiasm to go through all my pics and type stuff out.

Yes Chris, I've got to sort out and reinstall the LR valve body, but that shouldn't be too difficult now that the fault has been narrowed down. Swapping valve bodies only takes half an hour once you've got the car up on stands and the sump drained. I've got the speedo kit installed and working, but the inner cable keeps binding, and there's a bit of a story behind that... another day. Low volume certification is booked for next Tuesday, then all going well it's WOF and registration. Meanwhile I undertook another furtive run down the motorway tonight, and indulged in another little revel at the 800rpm drop at 100kph. Just wait until I get lockup going!
 
Thanks Warren. Good luck with the certification and with finding lockup! Much respect for all that hard work.
 
Hi Tor, and thanks. Low-volume certification is booked in for tomorrow and I will let everybody know the results. Being a little over-Rovered these last few weeks, I didn't so much as touch the car over the weekend, therefore everything is still as it was last time I posted. I have Graeme's LR valve body sitting alongside mine on the workbench for the stripdown and compare, but haven't mustered motivation yet. And in another hiccup, the output motor on the Dakota Digital kit appears to be faulty, so I've had to get in touch with them to sort that. It'll stall things a bit further, but I'm so close to the end now that I can just about call the project finished.
 
Thank you all, however there is a new fly in the ointment! The Dakota Digital box has a faulty output drive. Dakota have been very good and are posting a replacement unit to me... but they are currently on back order from the factory. That means Brown Rover is going to have to just sit in the garage and wait until it arrives. Annoying, but no more. Of course it means I won't be able to attend the P6 50th anniversary rally in my own P6... :cry:
 
I'm sorry to hear that Warren, could you not use a satnav as a speedo so that you can attend such a special occasion?
 
A GPS makes a fine speedometer, but it won't do for a WOF; without a WOF I cannot register the car; without those stickers on the windscreen the fuzz will throw their fuzzy ticket-book at me if they find me out on the road. And my insurance policy is voided. So sadly no, Brown Rover will just have to wait patiently in the garage.
 
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