Classic mph per 1000 revs.

Sorry but no luck with the 'search' facility.
Does anyone know the actual rpm per 1000 revs. in overdrive/convertor lock-up for an '87 3.5efi auto (ZF 'box)?
I've trawled through all my documentation before posting but any manufacturer's figure eludes me. According to my speedo & tacho it's around 24/25 mph but of course neither instrument is totally reliable. The tyres are nearly new standard fitment size ie 205/80X16. Thanks in advance for any info.

Zf locks up at 52mph

norseman said:

Sorry but no luck with the 'search' facility.
Does anyone know the actual rpm per 1000 revs. in overdrive/convertor lock-up for an '87 3.5efi auto (ZF 'box)?
I've trawled through all my documentation before posting but any manufacturer's figure eludes me. According to my speedo & tacho it's around 24/25 mph but of course neither instrument is totally reliable. The tyres are nearly new standard fitment size ie 205/80X16. Thanks in advance for any info.

Click to expand...

Perhaps u should explain a bit better "Does anyone know the actual rpm per 1000 revs" ?

My 3.5 RR torque converter locked up at 48mph just like all the other 3.5s at the time, and what a pain that was if you wish to press on, much better with my 3.9 disco which locks up at around 52mph.

So, let us know what you are after as my Haynes manual gives a lot of stats for the 3.5 RR I can have a look if you don't have that manual.

Do you really mean rpm and not mph per 1000 revs ? If its mph you want then my 89 classic was 5 speed manual worked out at 26 mph per 1000 revs in 5th, I would guess the auto will close to that as well.

Thought standard was 205/75 r16

But it does also depend on tolerance on the rev conter which runs from a pulse from the alternator so if the belts are slack wheelies won't have too much input.

Sorry guys, typo error - should have said MPH per 1000 revs.
Just out of interest the converter 'lock-up' road speed varies according to the model year. My '87 does so at 40 mph which is correct according to the (genuine LR) workshop manual, whereas my '93 3.9 used to do so at 52. Admittedly 40 is a bit soon if you are climbing a hill/accelerating, but you can always hold 3 on the shift until ready for the shift into OD/lock-up. On the other hand when cruising country lanes it's ideal for economy.

That's why it was a pain then driving up hills if the 3.5 auto lockup was 40mph, I thought mine was around 48mph but ha-ho it was a long time a go.

Thanks for the replies folks, seems that the info. I seek isn't out there - never mind, worth a try. I've a book, published in the 'nineties, about the history of Rover cars up to the P6 & the specs. I was seeking for the RR was included for every model/variant - seems manufactures feel we don't warrant that info. these days.

discool said:

That's why it was a pain then driving up hills if the 3.5 auto lockup was 40mph, I thought mine was around 48mph but ha-ho it was a long time a go.

Click to expand...

Torque lock should be around 50 MPH should be disengageable with kickdown.