As I left it last time the rear top “A” arms did not fit due to interferences with the rear shock, which again was entirely my fault due to not modelling the springs in the CAD model.
Below shows the revised version bottom V the original top…
Thankfully the wheels don’t interfere with the springs with a bit of room to spare at full droop which is a bit of luck, the wheels on the rear look pretty good…
However here is the next self inflicted stuff up. The wheels are from a 2008 C06 model which I thought would work with the Z06 big brake kit I have, however they won’t and it would take about 20mm of wheel spacers to get them to work, which I’m not happy about so the wheels will go on eBay soon and a set of Z06 wheels will be sourced.
With the rear suspension assembled I could try the CV joint for a fit, as expected the CV Boot interferes with the shock unit and shorter boots will need to be sourced. At least this is how I expected it to be and not a surprise!
Also on the suspension I’ve made the 16 spacers to go either side of the rod end joints on the top “A” arms (which give some castor adjustment if required) and the 8 spacers to go in the dampers to bring the bolt size down to 12mm from the delivered 15mm which I thought was a bit excessive. This leaves another 16 spacers to make to go either side of the shocks
Now having the Ultrasheild 5 point harnesses to hand which I am going to use, I’ve been able to trial fit them and finalize the 5th mounting point. Below you can see the floor parts of this all tacked in on the passenger side. Now it’s done I realize I could have done away with the diagonal tubes holding the seat bracket and combined them with the tube which supports the fifth point mounting, but that can wait for the MkII car.
The next realization was the shoulder mounting points as installed don’t work with the harness I have.
I was going to use eye bolts with clip in ends, but there’s not enough room between the back of the seat and the roll frame for this and the 3 bar length adjuster, the result is the 3 bar adjuster either ends up against my neck or further down on my chest, niether of these I like the idea of.
So they’re going to be cut out and I’ll go back to the idea of a round tube welded into the roll frame which the harnesses wrap around. The picture below show how the harness gets wrapped on the tube to prevent slipping (from Schroth)
Next was dealing with an issue that I had been aware of for some time which was that to get the engine in and out the adaptor plate and flywheel had to be removed from the engine, which long term was not going to work, so the offending tube needed to be removed and replaced with a bolt in version, for this I made the brace and brackets, welded on the brackets and then cut out the tube.
I hoped to heck that the frame would not spring too much in any direction after the tube was cut out and sure enough it moved a little as is inevitable but I’m still able to get the brace to fit. The 6 bolts in it are overkill I suspect but it’s done now. And the aim was to get a joint that would resist bending and get more than one or two of the bolts working in shear.
Yesterday I dropped the engine and trans back into the car, the aim being this time to get the exhaust mostly sorted and to have a go at getting the thing to fire up, just so that I know it’ll run in the end.
The original headers are fairly horrid but by swapping their sides and re orienting some flanges they now basically fit but there’s a bit of work to do to get the original cats fitted up, this is all being done to keep the engine and emission systems stock, which should help with registration.
The idea is the exhaust will look something like this when done…
The next thing I’ve started is the front steering tie rod extensions these are made from ¾” hex steel, the Ford steering rack is threaded at M14×2 and I had thought that the GM steering ends were also M14×2 but that’s wrong and now I think it’s M14×1.5, anyway the ends not being machined to final size until I know for sure.
One last thing I’d previously bought an Ozito cold cut saw well this worked well for a time until the blade went and the vise broke, so I took it back (thankfully there’s a 3 year replacement waranty on their stuff) and got my money back. Then I replaced it with the saw below from Hare & Forbes which was basically $25 more than the Ozito device and so far I think the thing is great. The blade that comes with it is rubbish, but good replacements are $11 each. I wish I’d has this thing at the start of the project, oh well.
The lower A arms have hade the ball joints fitted, this was not cheap, but I know the job was done properly. Apparently the Moog parts were sufficiently different in size that each part needed to be bored uniquely.
Now that was done it enabled the first trial fit of the suspension to the frame…
Below is the front left, which looks good to me.
With the damper out the suspension is able to drop some more so one of the worries I had on running out of travel in that direction has been overcome at least.
I would show you a picture of the other side except, I made two left hand side upper arms, Doh! At least I can count that as a spare and not scrap.
Next is the rear, which looks good except the damper interferes witht the top A arm so it can’t attach to the upright! Doh!
I had not modelled the springs in the CAD model and this has come back to bite me, sure enough now I’ve put them in there’s an interference in the model just like the real thing. I should have known better, luckily the fix is quite easy, just to cut of the brace tubes and move them out 20mm should do fix the issue. (Note the upright is on the wrong side, the tie arm will be to the front when the right part is on there).
So moving on, I’ve also begun the steering rack support, below is the MkI version…
This one I got carried away with and fully welded off of the car, which meant it warpped like hell, then when it was offered up to the frame I realized I’d read the drawing wrong, so a few wasted hours there then.
When I’d done it I didn’t like the design anyway so back to the PC to redo the design to use angle rather than box for the vertical tubes. Then I got lucky and found an even better piece of steel in the scrap bin of a local steel fabricators, so the MkII below was made…
Note its just tack welded, then it was tack welded into the frame…
And with the rack in place…
Or not as the case may be the CAD, predicted the rack would interfere with the two outer frame tubes, which it does and the next job is to recess and reinforce those, this I’m not worried about as the 50mm wide tube was a convienient size for construction but is excessive for the load on the tube, and I’ll be taking 15mm out of it at most.
Lastly I’ve made the required threaded inserts to support the the seat harness eye bolts. Again these are way excessive strength and weight wise but its not that much weight in the grand scheme of things.
These started off as 40mm steel bar, the eye bolts are 7/16″ UNF this and some other parts have shatered the dream of having the car fully metric.
Over the last week I’ve had some time to do some concentrated work on the car, the main thing is finishing the suspension ‘A’ arms, all 8 are done now I’m guessing there’s roughly 8 to 10 hours work in the fab of each one.
Maybe I’m slow maybe TIG welding is that slow compared to MIG in a day I can got 2 welded together having prepped the components previously so there’s 3 or 4 hours in welding one together when all the stuffing about is taken into account.
Then there was all the lathe work for the various tubes and fittings at the corners of each one.
Next for these is to take the lowers to have them bored for the lower ball joints and get those pressed in, a good wire brushing and painting is in order as well.
I’ve also got a few other bits tacked onto the frame, below is the beam which will act as the support for the upper harness mounts, through the holes there will be top hat section bosses inserted into which the eye bolts will thread.
A recent business trip to the USA enabled me to retrieve some parts piled up at a buddies place…
These are Corvette C5 axles the inner is no use to me and the shafts were too short, so for ease of transport they were cut down to just the parts I need. These are stupidly expensive to buy new just the bits I needed, so this was the best way to go.
These are the parking brake assemblies, they fit inside the rear discs, as the stock Corvette solution its too easy just to follow, finding the parts for sale was the hardest part. I expect most of these get trashed when the cars are broken up.
The 1UZFE motor often came with a hydraulic pump to power the cooling fan, to ditch this another pulley bracket is required to keep the serpentine belt routing usable, the old pulley won’t fit either, so a new one of these is required.
That’s it for the moment, at least I’m home for a little while now, so hopefully some progress can be made.
Since the last update the 4 upper suspension ‘A’ arms have been completed and one of the lower ‘A’ arms has also been completed.
Also I got the point where both seats are mounted, the drivers being adjustable which is a legal requirement here in Western Australia.
I finished fully welding together the box structures which form the base for the engine mounts in the frame and these are now tack welded into the frame also the transmission mounts are finished as well.
Since the pictures below were taken the engine and seats have been removed and the car is now back on the rotisserie to complete the welding on the engine mounts and a few other identified pieces.
Whilst the engine is out I’ll be making the stock headers fit by swapping their sides (minor tweaking required), which means between the air box and cats the engine will be entirely stock, which should help getting the thing on the road.
Beyond this 5 point harnesses have been sourced, so have C5 Corvette drive shafts and parking brake assemblies.They’re all in the USA still at the moment which is not helping but at least they are bought.
A few things happening lately have prodded me to do a quick update on the project.
After making some mods to my tube notcher I got the last of the fish-mouths cut, the most extreme angle to cut was 26.1 degrees, so then it was time to see all these notched tubes would fit together…
The next job was then to manufacture the jig for welding the A arms on, this was made using some 50 x 50 X 5 EA with 5/8″ locating drilled in it, stick welded (horribly) to a 50 x 50 x 5 SHS, the last hole in that being drilled after the two parts were welded together so as to make sure it was in the right place.
The picutres below show some of the process of putting the first 2 A arms together and the final results…
That’s a bit of luck, it fits!
This end was cut using the tube notcher and offsetting the part to the tool.
First tube tacked on and now for the second…
The finished results.
I’ve also got onto assembling the engine mounts from the laser cut parts. These more or less work but they’ll need adjusting as the engine mounts on the engine I think have turned out to be further apart than I had initially measured, but it should not be too much of an issue to fix the brackets.
Firstly I’ve got most of the tubes for the ‘A’ arms fish-mouthed there’s just 8 ends left to do which require more extreme angles than my tube notcher will currently do, I say currently as I’m going to mod it so it will.
Here’s the parts done to date in a box:
You can see in the picture some of the ends on the right would not be possible with the normal use of the tube notcher, these were achieved by spacing out the cutting tool to achieve the correct offset to match onto the large diameter parts you can also see in the box.
Next.
I got back the adaptor kit from B and C Products which has been done to an excellent standard. This has enabled me to get the engine and transmission joined together as you can see below…
Here’s the plate in more detail…
At this stage I’ve not fitted the flywheel etc, the purpose at the moment is to check the fit into the frame for the car…
Which it does, but only just, the tube running across the rear of the engine may need to be made removable, other wise fitting an removing the engine is going to be a total pain in the but. I need to work out a neat way to make this happen or I’ll leave it as it is.
Here’s more detail on the join, which explains why all the engine side bolts need to be pocketed into the plate…
next there was the job of getting the engine lined up properly in the frame, this was achieved by using a laser level that produces a reference plane…
Some pulling and tugging later it was done…
I then realized that I had yet another trip away from home coming up and a large pile of parts that I needed to get made, including engine mounts, trans mounts, seat mount brackets, damper brackets etc for the ‘A’ arms…
That’s 60 odd parts there to be assembled. The laser cutting was done by Action Laser Cutting for A$159 for all you see here which I think is a good price, espesially compare to the length of time it would take to produce all this by handlet alone accurately by hand.
Things I’ve managed to get done since the last post are…
The steering column support structure.
Note that the brake master cylinders are probably too close to the windscreen for their tops to be removed sensibly, I’ll probably be spacing them back an inch or so and extending the push rods to suit.
Then there was the lower “A” arm outers, I’ve turned up four of these that the lower ball joints push into. Note the poor finish on the parts due to ineptitude with the lathe on my part. The inner diameter of these parts is under size, it is expect that they will deform during welding, once welded I’ll take them to a local shop to be bored the correct size and have the lower ball joints pressed in.
Next is the front damper mountings…
I got lucky recently and found the holy grail of self builders everywhere… The unattended scrap bin! from this I’ve been able to source some 3mm plate as used in these brackets and various other bits of steel to be used for other brackets and jigs.
On the inside of the bracket you can see the remains of the paper pattern that was glued to the plate to give the profile to cut to.
Next is a MDF mockup of the fuel tank, this should hold 50 litres at this size, I’ve cut the width down 100mm from what was initially designed in the PC.
Then there are these:
Which are strips to be welded to the side of the chassis to enable the bulkheads that are in the side aluminium box structures to be bolted to the chassis (hopefully this’ll become clear when they’re on the car)
Lastly this strip has been attached along the lower edge of windscreen to form the support for the windscreen to be bonded to. I wanted something stiffer than straight strip hence the use of the angle but the angle was overkill, so lots of holes to get rid of the excess material.
A small update today, these are the stays for the radiator support, they are made from ½” 4130 Cr Mo steel tube, 4130 was used for no other reason than the material was easy to buy.
The square tube in the middle is temporary just in there to stop the arrangement distorting whilst the frame is on the stands and the proper stays had not been fabricated.
