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Discussion Starter · #1 ·
I have been intending on starting this thread for a little over a year now when I first started the project but am just now finding the time to do so. I was finally able to purchase my all time dream car in July of 2015. It came out of Oklahoma with 55,000 miles on it. It had a broken rear axle so it couldn’t be driven. Unique upgrades were a big brake kit, Hercules Muci wheels, Carbon Kevlar Spec clutch, and an MSD ignition. Despite many negative posts about the car on forums I bought it without seeing it myself but did have it inspected. For the price I paid I expected to have to go through the entire car but it was quite a gamble! Below are some pictures of it when I first got it.

I bought the car with a broken rear axle so needless to say, that was first on my to do list! I looked into having one made at a local machine shop that specializes in axles but went with the factory one instead. Custom would have been about $500 vs. $2,500 for factory. Still trying to figure out how you break an axle on a Diablo, not only once but twice!

Once I was able to drive it I came to the realization that it overheated after driving for about 20 min. It was quite a journey figuring out what the actual issue was and once I discovered what the issue was I felt like such an idiot for not figuring this out right away.

Tip, if you don’t have heat, and your car overheats, it’s probably your heating system not your cooling system! In Southern California we don’t really need heat but I should have check that first.

In my hunt to find the issue I replaced, radiator cap, temp sensors, rebuilt water pump, replaced and tested thermostats, flow tested radiators, and lots and lots of bleeding. I even took it to my local independent shop and they diagnosed it as bad temp sensors and air in the system. I finally decided that it must be a bad head gasket leaking air from the cylinders into the coolant. Since I was planning on pulling the motor and doing all of the gaskets anyway I figured I would go ahead and do the head gasket and hope that was it. I had also done a leak down test and found that the valves were far out of adjustment.
 

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Discussion Starter · #2 ·
Although I knew it was turning into a huge project I was actually really looking forward to pulling the motor. Having read other treads and how-to’s on this I think the only tip I have to add is to leave the mounting brackets on the front of the transmission and just unbolt the shift lever assembly and let it hang down next to the mounting brackets. It really just takes one person guiding the shift lever and transmission out as another lifts and adjusts the angle. Also, use a load leveler mounted lengthwise to the engine. You can set 2x4s going across the cam covers to keep the chains from hitting the cam covers
 

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Discussion Starter · #3 ·
Once I got the engine out and started taking things apart I realized just how good it was that I chose to do this sooner rather than later. The first find was a 8mm sheered off bolt and plastic debris in the oil pan!!! Turned out this was from the top center chain guide. I can’t even imagine how this could have happened! Any ideas? It had a long way to make it down to the oil pan. Luckily there appeared to be no damage to anything else along the way other than a flap in the oil pan that had broken loose as well. Next I found that there was significant build up on the pistons (it had been running very rich) and in the valves, along with many leaking valve seals and valve guides that were too far gone.
I brought the heads to a very reputable local automotive machine shop to do the valve work. I had them check all valves for straightness, grind valves and valve seats, new guides, pressure test heads, machine flat (heads were slightly warped), and adjust valves. They did all of this for about $2,200. I was quite happy with their work and it seemed to be a very good value.
I of course replaced all gaskets and o-rings including the head gasket and also the chain guides.
 

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Discussion Starter · #4 ·
While the engine was out I repainted the engine bay, cam covers, intake manifold, air filter boxes, relay box, frame, rear grill, taillight surrounds, etc. I also replaced most of the nuts and bolts or had them re-plated in gold zinc. The fresh yellow zinc looked so good that I went ahead and re-plated almost all of the yellow zinc parts in the engine bay. It really makes a BIG difference! I also had the throttle rods nickel plated. I also replaced all of the old hoses with steel braided hoses.
 

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Discussion Starter · #6 ·
Many of the bushings were in desperate need of replacing. Some appeared to be in good shape so to be easy on the budget, I just replaced the ones that were in poor shape. While I had the control arms off I went ahead and sandblasted and repainted them in satin black along with the springs and rear shocks. I bought new Koni shocks for the front. The bushings were actually quite easy to replace! It was probably about an hour of press work.
 

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Discussion Starter · #7 ·
I decided to switch from the Hercules wheels to Speedline Murci wheels. It turns out that the speedline wheels are a little small on the inner diameter. My 390mm rotors no longer fit. I was able to turn the rotor diameter down slightly along with taking about 100/1000 off of the mounting brackets to get them to fit. After doing this and adding 10mm spacers I found that they fit but when driving on streets with lots of small stones they would get kicked up and stuck between the caliper and the wheel. To fix this I took a small piece of furniture leg padding and epoxied it to the front of the caliper to act as a brush for any stones and debris in the wheel. Working great!
 

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Discussion Starter · #8 ·
There was some mention of this car maybe eating clutches in an old thread so I was curious to see what condition it was in. When I got it out I was a little surprised to find that it was practically new. I could still see the writing on the surface.
 

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Discussion Starter · #9 ·
It all went back together and in without much trouble. I still have an endless list of things to do on her but that’s ok. It’s endless amounts of fun, especially now that I can really start driving her!!!
 

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Discussion Starter · #11 ·
Still need to figure out a way to avoid scraping the front bumper on everything! Has anyone ever done a plastic skidplate on a Diablo? Here are some pictures of her now.
 

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Discussion Starter · #18 ·
Great job!


Btw, that is correct replacement for original Cavis wires, as they have nearly same resistance.

btw, Is waterpump rebuild staright forward thing, how does this go?
I sent out the waterpump for the rebuild. I think it was about $250. The impeller had a strange crack in it so I bought a WP for a VT to salvage the impeller off that which is the same. I just had them swap that over then sold them the rest of it for $75. I paid $155 of the VT pump so it ended up being pretty cheap. Worst part was getting the pump off. Just took a lot of fitting it with a plastic dead blow back and forth.

Let me know if anyone wants the name of the place that did the rebuild.
 

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Discussion Starter · #19 ·
Great job and great thread! I remember this car when it was for sale. I've always wondered what happened with it. Glad to see that it's getting a new lease on life. I also see you redid the front lip and mirrors back to red. Lookin' good!!
Thank you! I actually haven't even fixed the front lip. I've been concentrating on the mechanicals mostly. I want to find a way of not destroying it as soon as it's fixed, such as a skid plate. This is one of the next things on my list. The lip only looks different because I replaced the black tape with red that matches the car! lol
 

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Discussion Starter · #23 ·
The skateboard wheels should not be used, or if you have them take them off. If any real pressure is applied to them you may run the risk of damage. The main structural frame of the diablo ends in a box section around the trunk area, and skate board wheels are mounted to the small tube frame that extends to pick up the fenders, which is very flimsy compared to the main frame, and if too much load is put on them you will easily buckle those subframe members and lift the fenders up out of whack.
Yes, exactly. I have seen these before and thought about making my own and mounting them to the main frame rails. With them hanging so low though I feel like they could just snap right off on a speed bump or a dip in the freeway at high speed. I'm now thinking of doing some sort of reinforced skid plate.
 

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Discussion Starter · #24 ·
Awesome thread, and fantastic work.

I would be very interested in learning more about the MSD upgrade. The coils and energizers are a weak point in these cars.

Keep the information coming!
Thank you! As for the MSD, I don't have many details as it was already installed and am no expert in that field. Just learning as I go along. I'm an artist by trade. I can tell you that it was Lamborghini Dallas that did the conversion. I have the receipt. I can photograph the setup as best I can and give you details if anyone is interested. It looks like it would be a simple conversion to do.
 

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Discussion Starter · #26 ·
if you can post the details of the invoice that would be great, and any pictures too. I see MSD coils in one of the pictures. Is there a MSD ignition box too, or what is behind those coils?

I'd say for an artist you are a pretty talented mechanic, that's some serious work my friend.
Thank you. Much appreciated! I'm no mechanic, just good at figuring things out. I am honored just to have the opportunity to do these things. Life is good!

Here are some pics of the MSD setup. I can get better ones by removing the air box. Let me know if anyone needs that as you cannot see the wiring in these pictures and I know it's a bit unconventional.

I also snapped a few pics of the relay box which I realized I had left out of the previous photos. The original paint on these things is just HORRIBLE! I completely disassembled mine and repainted.
 

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Discussion Starter · #29 ·
decompiling that setup is something the community would certainly benefit from, thank you. I may let you borrow my LM Console in exchange for me taking a closer look at that setup :)

if the invoice shows the MSD Box # that would be helpful, the rest can wait.

cool setup, I looks like the OEM amplifiers are sitting right on top of the MSD box....very curious. Not an expert in this area either, but want to figure it out.
Sounds like a deal to me! But honestly, I would do it anyway. I can check the invoice for you tonight.
 

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Discussion Starter · #30 ·
Here's the info for the MSD ignition. Looks like it was MSD 6201 and MSD 8203 two of each. with a quick google search this appears to be about $700 worth of pars. Although looking at these online I see that they don't have the connectors on top like mine have. Geno was probably right that these are the OEM amplifiers. They appear to be siliconed on top of the MSD boxes.
 

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