1967 Lamborghini Miura P400 (Topo)
Total restoration
Restoration log by Dan Mooney




 

 

1967 Lamborghini Miura - Chassis # 3051

This Lamborghini P400 (production # 36) has been languishing in its current disassembled state for almost 40 years. Affectionately named 'Topo' by its longtime owners, the car is currently undergoing a total restoration in the Team CJ Workshops.

Purchased new by renowned gentleman racer, oil heir and sportscar personality Toly Arutunoff, 3051 has a fascinating history. Toly ordered the car while visiting the Lamborghini stand at the 1965 Torino Motor Show, believing it to be just the seventh Miura order placed. Toly raced the car several times shortly after taking delivery in the summer of 1967, and also used it as his daily driver for several years.












 



Update report - September 9, 2020

The following images show Corey honing the new liners to size.



Forged pistons are installed at .0035" clearance
Corey honing liners to size using our custom
torque plate
















Update report - August 21, 2020

Corey has now surfaced the tops of the liners so they are all perfectly square and protrude above the deck precisely .003".






















Update report - August 18, 2020
The following sequence of photos show Corey installing the new cylinder liners. During the installation process we used an arbor that Corey designed that is installed inside the main housings. Holes machined in the arbor allow us to insert a large threaded rod which helps Corey position the installation alignment tool centrally in the bore. With the cylinder counter bores heated to about 240 deg C, they expanded to approximately .002" larger than the new liners, which dropped into place perfectly. Once the block cools, the liners are installed at a press fit of at least .0035". The same arbor and threaded rod was then used to make sure that all of the liners were pulled and registered all the way down.







Preparing to install the new liners
Corey double checking the sizing one last time











Confirming the requisite press fit in the cylinder
counter bores










Special arbor and installation tool for the Miura block











Heating the counter bores to around 240 deg C
Installing the first of the liners

























































The liners will now be surfaced to ensure they are
the requisite height above the deck surface































Update report - August 5, 2020


A new set of bespoke ductile liners for the cylinder block.






















Update report - July 23, 2020

Corey has now completely rebuilt and reassembled both cylinder heads.






































































Update report - July 13, 2020

We have now completed all of the machine work to the cylinder heads, which are both ready to be assembled. The first photos in the sequence show the new radiator painted satin black.
















A reminder of how the cylinder heads looked at
the start of this project





 




Both heads have now been machined, repaired and
restored




























Heads will be assembled in the next couple of days
Some nice gains on the flow bench from Corey's
valve job





Update report - July 10, 2020




Video clip showing Corey surfacing the block


We have now removed all the old liners and surfaced the decks. Funnily enough the only flaw that remains in the deck surfaces is scarring from an old weld that was undoubtedly done at the Sant'Agata factory in 1967!




Machine out the original liners











A rarely seen view of the water jackets inside a
Miura cylinder block











Preparing to surface the block deck surfaces



































The majority of the pitting has now been removed
and the deck surfaces are smooth and true











Checking straightness with a straight edge











Remains of a factory weld!
Ready for the new liners





Update report - June 12, 2020



Dan Mooney explaining issues with the Miura block and liner replacement


































Update report - May 20, 2020

Hanging new Carrillo rods on the pistons.



























Forged Carrillo rod saves over 600g from the
rotating assembly
Comparison with Jaguar rod shows just how
diminutive the Miura rod is!

















Update report - May 15, 2020

Honing tappet guides and new forged piston set.



Honing the tappet guides to size























New forged piston side by side with the original
cast version


















Update report - May 13, 2020
The following sequence of photographs show Corey machining the cylinder heads.



Valve seat pockets machined to size











New custom valve seats pressed into place











Valve guides installed and honed










Machining bores for bronze tappet guides











Heating head prior to pressing in tappet guides











Tappet guides now installed in first head



































Installing guides in second head
To be continued!





 

Update report - May 5, 2020


























































Update report - April 21, 2020

Assembling the carbs with the custom oversized butterflies.

























































Update report - March 13, 2020
The first five photos in the sequence below show how Corey in the Team CJ machine shop dealt with the serious corrosion and pitting we found inside the Weber carburetors. Rather than go with an alternative set of carbs, we decided to machine the throats of the damaged carbs to eliminate the pitting, then fabricate and use slightly oversized (41mm) butterflies throughout.



The original carbs were badly pitted and could
not be used as they were
Corey machined the worst of the carbs first, removing
just enough material to eliminate pitting











All carbs were then machined to precisely the same
throat diameter










New butterflies will now be made to
precisely fit the new bores
Align honing the engine block























To be continued!
Align honed to perfection









Jake examining the Miura body after media blasting











































































































Update report - February 9, 2020
This week's update is all about camshafts! We had the cams measured and tested and I am delighted to say that we could not have received a better report card. With no discernible wear, all that was required was a light polish of the lobes and journals and all four camshafts are now in pristine, virtually 'as new' condition.

Before the cylinder heads were disassembled, we noted that the camshafts were very difficult to turn in the cam saddles. In fact all four cam tunnels required an align hone, which you can see Corey performing in the photos below the camshaft report. Following the align hone, cam saddle clearances were a consistent .002" across the board and the cams now spin freely.







Corey align honing the cylinder heads












One of the cam caps after the align hone
was completed
Trial fitting cams and measuring clearances











Jake explaining corrosion issues with the Miura body shell




































With the body now mounted on one of the roller-hoop rotisseries, we have started cutting away some of the obviously corroded panels prior to media blasting everything back to bare metal. Unfortunately, some previously installed repair panels also had to be removed revealing some severe corrosion lurking beneath.



At first glance, the monocoque doesn't look too bad











Unfortunately, closer examination revealed some
serious corrosion issues












This panel had been replaced in the past










Not a pretty sight beneath











Another suspect looking repair panel
More rust lurking beneath










2 of the worst looking repairs I have seen in a while
Yet more rust lurking beneath




Earlier this week Josh disassembled the short block and transaxle.

















View inside the crankcase

































































































































































The following sequence of photographs shows the disassembly and inspection of the Weber carbs. We already knew that this car was one of the first Miuras ordered and built, and the extremely low Weber serial numbers (16, 52, 59 and 88) mean these are almost certainly the original carbs.



The Miura's carbs have been carefully stored for
over 40 years












Carbs have suffered from corrosion and exhibit
significant pitting










Previous epoxy repairs at the base of the fuel bowls























This is just the 16th Miura Weber carb made!
Carbs now fully torn down and inspected










All component parts carefully stored





Corey has been busy machining and trial fitting all the various components for the valve train. He has machined custom valve guides, tappet guides, valves and spring retainers.




Machining the first valve guide











This protruding step inside the spring pocket will
be removed
This modification is necessary because of the
upgrade to valve seals










Machining a mock-up valve












Machining a tappet guide from bearing bronze stock











Head is counter bored to receive the tappet guide










Tappet guide pressed into place
Mocking up the valve spring retainer










New retainer design allows the use of
shims to achieve desired valve lash
Trial fitting valve train










Smaller, lightweight tappet in place inside
tappet guide





Front and rear suspension has now been restored, rebuilt and loosely assembled.

































The first six photos below show Corey dealing with a broken and seized stud. The next photos in the sequence demonstrate how we are going to put the valve assemblies on a strict diet!

The original tappet buckets are unnecessarily large and heavy, and they ride inside aluminum tappet bores that have been damaged due to contact with the steel tappets. The springs are also unnecessarily oversized and heavy, which in turn means the spring retainers are also on the portly side! During the rebuild we will be using smaller, much lighter components in the valve train, and also press fitting new tappet bores. The new custom spring retainers will allow us to use a more effective shim system to set and adjust valve lash, and we also be using custom guides that will allow us to retrofit valve seals throughout. Even before we have compared the weight of the old valves versus the custom valves we are having made, we are seeing a weight saving of 80g per valve assembly, meaning 1,920g across all 24 valves.




Broken and seized stud























Installing the new threaded insert











Putting the valve train on a strict weight loss program
Original tappets, springs and retainers are all
unnecessarily heavy










Original spring retainer
Custom TCJ retainer










Original valve springs
Custom TCJ valve spings










Original tappet
Custom TCJ tappet










80g weight saving per valve assembly






Disassembly and inspection of the cylinder heads.















Removing the large and very
heavy tappets



































Original bronze seats and a scary looking valve job!
Overall cylinder head castings are in excellent
condition with no serious corrosion evident




Time to get the engine and transaxle rebuilds underway!

Although we understand this engine had a partial rebuild performed many years ago, it has not been run since and is actually seized at this time. Having removed the cylinder heads, it looks as if the heads have been serviced but the bottom end does not appear to have been rebuilt. Although we have yet to tear down the short block, it appears that the original Borgo pistons are still installed.
More on this as the disassembly progresses.





























































































We have now blasted the front and rear bonnet subframes back to bare metal and sealed them with epoxy primer. Both subframes will be repaired prior to painting, especially the rear subframe, which is quite badly corroded in the area where the hinges are attached.



Front subframe is more complex than its
rear counterpart
























Rear subframe has some significant rust that will
be dealt with prior to painting











Corrosion at the pivot point for the hinges
















The following photos show the reconstruction of one of the damaged (previously repaired) control arms, and also an absolutely beautiful new fuel tank.



Damaged control arm had been previously repaired
by brazing washers around shock mounts











Fabricating a new shock mount
New shock mount welded in place










Factory did not clean back welds, so we left our
weld beads to look as original as possible
Shock mount holes indexed and drilled










Fabricating the new fuel tank











The finished article





We are very fortunate with this project that the car came to us with a large number of extra spare parts. As we begin rebuilding the suspension and steering, we have already needed several of those replacement parts, including an alternative rear hub carrier and some major steering rack components.



About to tear down the steering rack
Steering shaft is badly corroded










Fortunately we had a good used replacement
on hand
Rack housing blasted and cleaned up






















Original and rarely seen Oralian steering rack
damper











Badly damaged original rear hub carrier
Thankfully a good replacement hub carrier was
included in the spare parts that came with car






















Suspension control arms have been crudely repaired
and will need extensive repairs
This piece has a washer welded in place as part of a
previous repair











Original Armstrong shocks will be replaced with
Konis





Lamborghini Miura bonnets (and rear engine covers) are extremely susceptible to galvanic corrosion because of the way the aluminum outer skin is fitted over the top of a lightweight steel subframe. The following sequence of photographs show the removal of the bonnet outer skin revealing significant corrosion in the outer flanges of the aluminum panel.



Preparing to de-skin the Miura bonnet












Rivets are first drilled out










Folding back the alloy out flanges reveals
significant corrosion












Galvanic corrosion is present wherever steel meets
aluminum










Lifting away the outer alloy skin











Extremely lightweight steel bonnet skeleton
The alloy bonnet skin weighs 32 lbs










Interesting to note that the chassis black paint was
applied AFTER the subframe and outer skin
were assembled together
The front wheel arches must have been installed
prior to any black paint being applied






De-skinning the engine cover has revealed a fair amount of galvanic corrosion everywhere that the aluminum skin came into contact with the steel frame.




Rarely seen steel structure that supports the
aluminum outer skin











The rear cover skin weighs a mere 21 lbs























Removing the steel wire from the bottom edge of
the allow panel





























Removing the aluminum boot floor assembly and corresponding inner wheel arch panels. The boot floor was held in place with 132 rivets.


















































































Yesterday we were delighted to receive a visit from Topo's owners. Rob and Jan visited the Team CJ Workshop to deliver a van load of spare parts and to check in on progress with the Miura. Among the many boxes of parts were Topo's original seats which had been restored and re-trimmed in Michigan in 1984. Interestingly, there was also a spare (third) Miura seat still in its original hide cover, so we were able to compare the untouched original seat with the restored seats. The Michigan trimmer did an outstanding job and replicated the original factory padding and stitching extremely well indeed. Thankfully, Rob and Jan also did a great job of protecting and storing the restored seats in the ensuing 35 years, so they remain in perfect condition to this day!

The first few photographs in the sequence below show Francis stripping the bonnet back to bare aluminum. The fourth image shows galvanic corrosion at the right/rear edge of the bonnet.




Francis stripping the paint and primer from
the bonnet











The green layer is an etching primer that adheres
extremely well to the aluminum
Typical galvanic corrosion where aluminum
meets steel










Bonnet is now stripped to bare aluminum
Rob and Jan checking in on Topo










An original factory Miura bucket street
Interesting to observe the original factory trimwork










Note how the factory finished the trimming beneath
the seat base
Topo's seats were restored in 1984










Comparing Topo's restored seats with the original
I'd say the trimmer did a superb job back in 1984!




The following sequence of photos show Francis stripping the paint, primer and filler from the rear clip. The rear wings and boot compartment are aluminum, whereas the transverse braces running across the body are steel.



Francis using 'aircraft stripper' to remove paint
and primer by hand
It looks very much like factory primer and one
coat of paint










The aluminum panels that form the rear clip have
suffered only very minor damage
























Note magnet attached to the steel brace panels






















The panel behind the rear window is also steel
Time to strip the bonnet!






















Rear bumper grille appears to be in its original finish
Interesting that it does not have the hardwood insert
noted in chassis # 3186 (also a 1967 P400)











Comparing the original 'satin' finish to a
traditional 'chassis black'










Fuel tank is not in great condition and will
be replaced











Insulating panels






Off the road since 1980, this 1967 Lamborghini Miura P400, affectionately known as 'Topo', is about to undergo a total restoration in the Team CJ Works.

The first owner of this special car was legendary racer, collector, raconteur, author and car guy extraordinaire, Toly Arutunoff. Mr. Arutunoff bought the car new in 1967 and immediately took it racing - because that's the type of thing he did!



Toly Arutunoff with Topo in 1967
Only Toly Arutunoff would buy a brand new Miura
and take it straight to the track!











Toly racing in Montgomery, Alabama in 1968










In the owner's garage, awaiting restoration























Loaded up and bound for the Team CJ Works
Bye for now!











Safely in the Team CJ Works


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