SD1 V8 EFi VDP renovation & Morris Minor Restomod

[PRN2K]

Glad to hear your thoughts on the ZF4HP box; it appears to be viewed as one of the best mechanical autos before ecu's took over. I'm taking the conversion quite seriously as I'm not a fan of the obstructive feel of the LT77, although it could have been a bad example. Against normal preference, I (think) I want an auto to enjoy this SD1 at a more leisurely pace than my other cars - so hope to build it to be capable of maintaining speed rather than gunning it out of every corner.

However, shocking fuel consumtion appears to blight this combination, so if I really do enjoy using it on a regular basis it may cause a re-think!

And with respect to paint, in such tight build confines I much prefer to tune the mechanicals to my taste then partially strip and farm-out a quality respray once I'm done...

Edited by PRN2K on Friday 9th February 18:08

[skwdenyer]

PRN2K said:

Glad to hear your thoughts on the ZF4HP box; it appears to be viewed as one of the best mechanical autos before ecu's took over. I'm taking the conversion quite seriously as I'm not a fan of the obstructive feel of the LT77, although it could have been a bad example. Against normal preference, I (think) I want an auto to enjoy this SD1 at a more leisurely pace than my other cars - so hope to build it to be capable of maintaining speed rather than gunning it out of every corner.

However, shocking fuel consumtion appears to blight this combination, so if I really do enjoy using it on a regular basis it may cause a re-think!

And with repect to paint, in such tight build confines I much prefer to tune the mechanicals to my taste then partially strip and farm-out a quality respray once I'm done...

Edited by PRN2K on Monday 15th January 19:33

IIRC there’s a mod for that box possible to allow torque converter lockup in 3rd as well as 4th; presumably that would aid consumption?

[PRN2K]

That’s interesting and desirable, I’ll look it up. Thanks!

[PRN2K]

Weather is still challenging my progress, but one mild day allowed be to underseal the visible rear end



Once dried for a day or two, the exhaust could go back in





Rotating the primary pipes should offer the chance to increase clearances, but only after the propshaft is re-installed

However, other clearances look good

n I



I dressed the leading edge of the back-box just in case it should ground-out




And that's the exhaust done...for now at least, subject to aural-focussed changes,,,,,,




So onto the rear axle refit- at least a start before the cold set in



Whilst also removing the bonnet to prepare a tidy up of the front end with a top coat

Edited by PRN2K on Monday 29th January 21:59

[PRN2K]

Front body sanded, Hydrate 80’d then prepared with Epoxy primer:



Then top-coated:



But more interestingly:

Before refitting the rear springs I investigated wheel travels vs exhaust and wheelarch clearances and found some surprising results:

Due to the bumpstop design (45mm long elastomer), the rear suspension doesn’t enter the rear arch in pure heave. It may in (extreme) roll, but that tucks the tyre inboard, missing the arch anyway.



So my conclusions are:

Now that my rear exhaust is integrated into the ‘groundline’ of the rear underbody, the rubber bumpstop is too stiff to allow the new usable suspension travel- it needs to be replaced with a longer, more progressive rate celasto item that sits on a shorter platform so that the full 45mm length of the current bumpstop (+ another possible 15mm) is usable travel.



These are the clearances with 25mm of bumpstop compression (60% of overall length)




Clearly, the wheelarch brow sits well above that usable range, so tyre contact isn’t possible. This means a 40mm increase in tyre offset can be accommodated to provide a much more appealing stance. This image shows clearance at axle to bumpstop platform contact.



In summary, after MOT and initial driving assessments, I expect to reduce ride height but maintain comfort-at least at the rear. I haven’t yet removed the front springs to understand constraints there…

Edited by PRN2K on Saturday 10th February 00:09

[skwdenyer]

PRN2K said:

Front body sanded, Hydrate 80’d then prepared with Epoxy primer:



Then top-coated:



But more interestingly:

Before refitting the rear springs I investigated wheel travels vs exhaust and wheelarch clearances and found some surprising results:

Due to the bumpstop design (45mm long elastomer), the rear suspension doesn’t enter the rear arch in pure heave. It may in (extreme) roll, but that tucks the tyre inboard, missing the arch anyway.



So my conclusions are:

Now that my rear exhaust is integrated into the ‘groundline’ of the rear underbody, the rubber bumpstop is too stiff to allow the new usable suspension travel- it needs to be replaced with a longer, more progressive rate celasto item that sits on a shorter platform so that the full 45mm length of the current bumpstop (+ another possible 15mm) is usable travel.

These are the clearances with 25mm of bumpstop compression (60% of overall length)




Clearly, the wheelarch brow sits well above that usable range, so tyre contact isn’t possible. This means a 40mm increase in tyre offset can be accommodated to provide a much more appealing stance. This image shows clearance at axle to bumpstop platform contact.



In summary, after MOT and initial driving assessments, I expect to reduce ride height but maintain comfort-at least at the rear. I haven’t yet removed the front springs to understand constraints there…

Edited by PRN2K on Thursday 8th February 18:52

More excellent work.

IIRC, the Vitesse sat 30mm lower all round. I don't recall any differences to the other front suspension components.

If lowering further, I believe people have had trouble with static camber, bump steer and camber gain, etc. - all typical McPherson Strut lowering issues. Obviously the Vitesse suspension set-up was firmer. If you're looking for, say, 30mm lowering without compromising ride quality, you might run into some of those issues, but overall 30mm should be fine.

Serious lowering would most likely - ideally - require moving the ARB mounts, rack and radius arms up relative to the chassis, or accepting compromises in handling, tyre wear and so on

[PRN2K]

You’re correct that Vitesse was 30mm lower, and Rimmerbros can provide those springs & allegedly 60mm lower options (which is probably going too far!). However, front and rear spring packers to raise the ride height to around a 45mm drop are easy to make.

I do think rear Nivomat self-levelling was introduced in part because of the oversight with the low hanging exhaust which restricted bump travel. And again,fortunately RimmerBros can offer the stiffer rear springs to suit non-Nivomat dampers.

Reference front camber correction, an offset spacer between strut and top mount can address both a 15-20mm ride height increase and camber/castor correction if required (or just re-position the studs on the top mount bearing rather than re-drilling the body).

Having said that, the front subframe has protruding mounts that could be removed to raise both links and roll centre if the sump was ‘re-shaped’:

|https://thumbsnap.com/rU7e1dRp[/url]

And if necessary, rather than shimming the steering gear, I’d probably fit Rose-jointed track-rod ends like the Moggy to tune Bumpsteer to around 5deg/m toe-out.

One advantage of the VDP front spoiler is that it doesn’t compromise lowering like the later Vitesse item so I just need to understand the other speed-bump clearances etc. And I see no real option other than adjustable dampers to tune control with the final solution. I have GAZ adjustables on the Moggy that were built to my spring rates (and superior to generic Spax options) so I’m quite happy to use them again.

Edited by PRN2K on Saturday 10th February 01:19

[PRN2K]

I’m long overdue proving an update. No, I haven’t given up but the constant rain over recent months did curtail my enthusiasm to be working outside-so I’ve been focused on work and family matters instead

All I can therefore add is both axles rebuilt:



And at the front, that includes new oil hoses and clamps for engine oil, gearbox & new PAS cooler








I also removed the air horns and fitted a pair of more discreet items



I’ve disconnected the electric fan to first establish if the OEM viscous fan works correctly and if therefore it’s actually even necessary; the irony being of course it blocks some airflow so may be causing overheating unless activated!

I also filled and bled the brake hydraulics



And a refresh of the wiring loom to address cracked injector wires and a few broken connectors





So, not huge progress but she’s slowly coming back together, and the weather is finally looking much more appealing…

[Flying Phil]

Thanks for keeping us updated. Nice to see the RV8 being appreciated.