ZF 4HP22 step by step.

Hi Peter,
Wasn’t sure if the thread was still being read by anyone. As I do have a massive task in front of me, it is good to hear your positive remarks. I'm not sure if it will work out but worthwhile if I do succeed.
It would be great if I could talk to the owner of the converted Stag, there some issues that are different to Rover installation. For instance, I picked up an XJ40 ‘box last night, and first thing noticed the different spigot on the Torque converter. Not sure how I’ll deal with that.
 
I do have a torque converter which has a overall diameter of 300mm, Can anyone tell me whether this a small or medium size?
According to Ashcroft Transmission bigger is better, I think this one is smaller in diameter than the flex plate, so should be OK.
Paul
 
Hi all, anyone spoken to Andy (@eightofthem) lately. I tried emailing a few weeks ago and I PM'd him here over the weekend? Desperately need a need control cable or a suggestion for keeping the ferule on the end in the mechanism. The one I have the pin moves sideways and comes out and I really can't afford to pay some one to put it back each time!20230522_071750.jpg
 
One the plus side I can vouch for Andy's skills. 12000mile and 6-7 years in the fluid is as as new, no smells, no particles, no leaks.
 
Hi Peter.
Sorry I have missed your callings, my old email has been closed by Sky and I can no longer access it.
I will ping you a PM with my new mail address.
The cable should not come out of the cam, the only way it will do that is if the cable is slack enough to be pushed backwards when the throttle returns to the rest position, it will then roll off the cam and work out of the slot it sits in.
Is the crimp set on the inner cable near the clevis fork?
 
eightofthem said:
Hi Peter.
Sorry I have missed your callings, my old email has been closed by Sky and I can no longer access it.
I will ping you a PM with my new mail address.
The cable should not come out of the cam, the only way it will do that is if the cable is slack enough to be pushed backwards when the throttle returns to the rest position, it will then roll off the cam and work out of the slot it sits in.
Is the crimp set on the inner cable near the clevis fork?
Click to expand...

I didn't install it. So basically, it is too slack? Could the crimp move or the cable stretch perhaps?
 
PeterZRH said:
I didn't install it. So basically, it is too slack? Could the crimp move or the cable stretch perhaps?
Click to expand...

Yes I would say it's too slack or it is becoming too slack when returning to rest.
The crimp can move up the cable if it's returning hard back into the inner sleeve.
 
I've got the parts to connect the torque converter to the crankshaft (as per the photos on page 2) but can't find torque wrench settings for the 3 sets of fasteners - has anyone got them or can tell me where I can find them? It's a 4.6 engine and the largest of the 3 torque converters just in case that makes a difference.
 
I thought if I find anything useful as I proceed that's not already covered I'll add it just in case it might aid someone else with this conversion.
Torque settings - the 4.6 engine uses a different arrangement to that used in this sticky and there's been a few factory updates on these, as far as I can tell the figures I'm using are the latest revision for the 4.6: 57-66lb/ft for the cap head bolts in the spigot adapter, 33-41lb/ft for the drive plate clamp ring and 44lb/ft for the torque converter (the largest of the 3 sizes).
My LT77 bellhousing to engine bolts don't all fit my ZF as some of the bolt shanks are too long - I've used 1¾" x 3/8" UNC with ½" shank instead.
 
Hi. I have a ZF HP22 box with HP24 internals in my P6.
Are there any changes needed to the standard box to suit the P6. Ive been told that you can change spring weights etc to better suit the car?
 
They are en electronically controlled box. You should have a controller somewhere and it will most likely have variable maps without the need to work on the box itself. I've actually changed the diff gears to the 2200TC set lowering the ratios to 3.54/1 Gives much better slow speed performance/ throttle response and the overdrive gear is somewhat more useful. Though I haven't tested the latter.
 
mikecoombs said:
They are en electronically controlled box.
Click to expand...
Must admit I believed the basic HP22 was a hydraulically controlled box, and the HP24 the electronic one (albeit a later HP22EH would be electronic)? An HP22 upgraded with HP24 internal components would still be hydraulic? Interested as I'm thinking of going down this route when my BW65 eventually needs work.
 
They are all hydraulically operated. I have both types and they are both electronic controlled however I recall earlier boxes had fewer solonoids in the valve pack. The very early boxes may well also be mostly hydraulic, with the torque converter clutch electrically controlled to allow manual lock out
 
If you get the LDV box it's cable controlled, and with a cable speedometer as well, but they're getting rare now
 
MrC said:
Must admit I believed the basic HP22 was a hydraulically controlled box, and the HP24 the electronic one (albeit a later HP22EH would be electronic)? An HP22 upgraded with HP24 internal components would still be hydraulic? Interested as I'm thinking of going down this route when my BW65 eventually needs work.
Click to expand...

mikecoombs said:
They are en electronically controlled box. You should have a controller somewhere and it will most likely have variable maps without the need to work on the box itself. I've actually changed the diff gears to the 2200TC set lowering the ratios to 3.54/1 Gives much better slow speed performance/ throttle response and the overdrive gear is somewhat more useful. Though I haven't tested the latter.
Click to expand...
I can’t help with the springs etc in the control unit but your box sounds like mine, a non-electronic 22 casing with clutches, gearsets and pump from an electronic 24 (all 24’s are electronic afaik). There’s no electronics in this mongrel box, it’s 100% hydraulic control and operation including tc lockup.
 
I have a 24 with no electronics. I was going to put a tuned Rover engine into the Cresta so needed a strong box, but then the LS3 came along.

I might just drop in up under Sparky if I ever get the time
 
ratwing said:
I can’t help with the springs etc in the control unit but your box sounds like mine, a non-electronic 22 casing with clutches, gearsets and pump from an electronic 24 (all 24’s are electronic afaik). There’s no electronics in this mongrel box, it’s 100% hydraulic control and operation including tc lockup.
Click to expand...
The all mechanical shift control is fundamentally in a self-contained "block" which is application specific. The control block you need is a Range Rover item which you fit to whatever 2WD ZF4HP variant you have. I believe my box was a Jaguar XJ40 item which given the 6 cylinder revs to 6.5k and has totally different torque characteristics would give totally the wrong shift points if this were not changed.
 
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