Master brake cylinder testing

Now I've read many say that one should just have faith in your basic ability to do up some brake unions and if there are any leaking joints when the body is on (the brake master cylinder is fixed into the body before it goes on so difficult to test in that configuration unless the body is stored next to the chassis. Mine is 50 feet away!)

Whilst I have some faith in my ability I have less trust that I know how the Rover 200 series master cylinder works so I'd rather get to the bottom of that now.

To that end I have made a plywood bracket to fit the master cylinder in a near enough approximation to its final position so I can test both the cylinder and and the brake system before fitting the body.

Finding the rear part of the dual cylinder not working to start with I separated it from the big vacuum disc to clean out some more.

Flushing brake fluid through does the trick, all the gunk is cleared and both pistons pump well.

The reservoir master cylinder is reattached to the vacuum chamber.

The last thing before filling up with fluid is creating remote bleeds. Kits are available but not really necessary, just some more brake pipe and a couple more unions with a bit of thought to routing and I have remote bleeds available the moment either rear wheel is removed.

Above rear offside. Below nearside.

Once I'm happy that the system has integrity I will attach these as per the rest of the brake lines.

brake lines pt 4

The final run. With the engine out I can get in with fitting and attaching the main run between the rear brakes to the front. My drill is too big to drill in the rear end of the tunnel however Machinemart / Clarkes do a right angled drill chuck to aid with such things.

The two main things here are to ensure the run doesn't foul where the body needs to sit and secondly to ensure the fixings comply with the IVA manual. From all I can tell (and others before me) that whilst it specifies that electrical wiring need fixing every 300mm, break lines (under the category of hydraulic pipes) need fixing appropriately. Most seem to do 300mm or less. I'm doing 200mm because I have enough clips to do so.

I'm also not that keen on rivnuts - threaded inserts that are fixed like rivets. I'm happy making my own threads so out with a metric m4 tap for my some head hex bolts, with spring washers.

Once again the ratchet straps come in handy as my second pair of hands making things easier to route and fit.

The pipes actually will go vertical to the master cylinder body connection about 6inches from the inner rail hence the masking tape a temporary fixing!

With fixings in place.

Next up testing the master cylinder and the unions.

Christmas hiatus

Time for a bit of a pause. I've nearly run out of bits that I can install in the logical process at the moment - need to acquire some more parts namely all the things for the fuel system. The dependancy being things I need to fit whilst the engine is out. Being natually optimistic I'm hoping that once I've done these things the engine will go back in and stay in! I'm sure "famous last words" spring to mind.

So what's needed:
Fuel pump capable of delivering fuel required for the V8 - from memory a rating of 225 gph at 4bar seems to be lodged in my mind. To put another way a Bosch 044 is the EFI pump most seem to recommend. Secondly the fuel system needs regulating to keep the pressure at the injectors at 58psi.

Yes I know I'm mixing my metric and imperial units but so does everyone else!

The one item I cannot source from elsewhere will be the AK fuel tank. Whilst AK could supply the required dimensions I don't plan making it myself. Jon builds it with a built in swirl pot to help alleviate fuel starvation under heavy cornering etc.

Finally I need to consider filter(s) and fuel pipe and routing.

I'm continuing to research the various options. I'm leaning towards the following at the moment:
a high flow about a 20 micron prefilter which flows into
a pump which drives into the
regulator / small particle filter about 5microns - the combinted one which is used in many LS swap projects in the US is the one from the LS2 Corvette made by Wix.

All these would mount towards the rear end of the chassis next to the prop shaft - allows a short return line versus putting the regulator in the engine bay and running a return line all the way back along the chassis.

So these along with fuel tank will be the next purchases in the new year plus other items in my engine mods / config post coming soon.

Brake lines pt 3

So having gone as far as I could with the engine temporarily stored in the chassis I now need it out of the way so that I can get full access to the transmission tunnel.

I've fitted the transmission controller back into the transmission pan, sheared a bolt and removed said bolt. See transmission TCM post.

The metal frame work which supports the body shell on top of the transmission tunnel presents a small obstacle when getting engine out with garage door shut but with a bit of jiggling out it comes. I measured up for the prop shaft before removal but it's goin to be ages before I get that so a bit pointless at this stage.

Look at all that space

As you can just see I could probably have placed the T-piece 3 way junction in a better place as with my modified chassis there's less room for the main front to rear run to double back on itself but a bit of careful bending and all is fine.

 The ratchet straps are coming into their own again being my temporary hands to locate the pipe as I make the bends

Putting things back

Another of the big tasks was to put the transmission controller (TCM) with it's new identity, back into the transmission itself. Seemed like ages ago when I took it out and sent off to the States - only a few months in reality.

With the car back up on stands and higher than ever before to give me lots of room it was time to head underneath. If you remember from previous the 6L80E transmission has it's own computer which takes a couple of signals from the Engine Control Module (ECM) like RPM, calculated torque and maybe a couple more - and then makes it's own decisions on gear changes  based on the table parameters in its tuning.

Now it has a new identity of a 2011 Corvette as opposed to 2012 Camaro it should be simpler in operation, no longer requiring incoming signals from a Body Control Module.

The tap shift / flappy paddle gear change runs on the CANBus (internal computer network for cars) which SpearTech have hooked their box of tricks into - effectively a set of resistors which when engaged by the switch, inform the TCM to change up or down a gear when in Sport Mode which in turn is selected by the gear lever selector.

Above shows the TCM unit itself bolted back onto the valve body which in turn is bolted back into the bottom of the transmission. All the Torx plus bolts are torqued to 8Nm.

 

Lots of room and light this time and even one handed socket wrench action shots possible.

Happily inserting this in is alot easier than when I got it out as I actually know what shape it is and what it needs to locate into.

Firstly importantly the rubber grommet seal has to go back into the bottom of the transmission where the four holes are located in the middle of the below picture. I think I must have been a magpie in a prior life - I just love looking at shiny metal!

 You can see some of the clutch packs that contribute to the smooth gear changes, normally these are all sloshing about in transmission fluid.

Seal back in place so now it's time to insert the valve body TCM combination.

Another action shot below, I think my other hand is holding it in place. The glasses whilst not necessarily attractive do make doing this stuff alot easier!

The trickiest bit of all this was actually to get the 3 parts of the control switches all back together as one. Just a bit of jiggling and wiggling best done before torquing the valve body bolts back up as I found out below.

All done and filter back on too. Given the no mileage of this engine and how clean the filter was I opted to replace the original. I will see how this gets on with the option of replacing with one with a larger aperture which the drag racers in the US use for higher flow.

All done. Apart from over torquing one of the sump bolts and shearing it.... luckily after a couple of days of head scratching I got it out, the actual thread on the transmission was ok so locating a replacement and all ok.

It rolls. A milestone achieved.

A milestone has been achieved. With all the suspension on I can put some air into the build wheels and drop the car down off the axle stands to check initial ground clearance with the engine in situ. Whilst the rest of the car won't be 'on board' this is still a good time to see how good or bad it is as the body etc will cleary have an affect however the worst of the weight is in the engine / chassis / suspension.

In my excitement I forgot to clear the decks before taking the photos so there's lot's of clutter there that I wouldn't normally allow in a picture.

Rusty but functional build wheels on.



 

Spot the difference... look below. No axle stand support! I rolled the chassis back and forth to move it a bit across the garage and it rolled very easily - surprisingly easily considering the engine is in too. Very happy.

 

 

 

And a couple from the front too. I'm quite pleased how central the engine is between the front and rear wheels - so many modern cars the engine is as a compromise over the top of the front wheels leading to balance challenges.

 

Final diff bracket

The last item on the rear suspension setup is the AK supplied diff bracket. This bolts to the two chassis uprights and the tail end of the inner wishbone shafts. Fairly simple affair that I'd been holding off until I had light and decent eye protection that I could see out of for drilling upside down.

The bracket is the angle iron piece with the triangular segment to allow fuel line and return to pass through.
The holes in the AK bracket are already predrilled so it's a case of being happy with the alignment and then drilling up. The bolts are fed in from above - there's a cutout you can just see in the upright and then they drop down. I used high tensile M8 bolts with nylocks.

 I need to make a plate or get AKs one for the underside of the diff again to protect fuel hoses from a grounding.

Drive shafts

The last things to be done on the drive shafts are the dust covers, and final torque and loctiting of the hub/shaft joint.

The jury is out as far as the effectiveness of the driveshaft dust covers and most Cobra builds I've seen don't have them refitted. However as I had already stripped treated and por15ed them along with the fact that Jaguar thought the would be a good idea I am refitting them. Just a case of a few pop rivets plus stainless jubilee clips and they are fitted.

I just need to find a suitably sized rubber grommet to cover the grease gun hole - Wards out of stock with no plans to get more. Clearly greasing the UJs before fitting is a good idea.

Inner end of drive drive shaft completed too. 

Finally as you can see from the phot above the shaft castle nut is on with the split pin meaning I have loctited the inner third of the driveshaft splines with blue loctite and the castle nuts are torqued and the split pin inserted.

Brake Lines pt 2

Next up the brake lines to the rear inboard discs. Same as the front a 3way union is used to split the rear line for the two callipers.

An m6 set screw tapped an bolted to the chassis. 

Bend both pipes to suit positions

A bit more bending and fitting and then the pipe can have a pipe clip fitted as below.

Next up the long run between front and rear - I will have to wait until I'm ready to lift the engine out for that as it's impossible to drill the fittings even with the right angle drill adapter.

I need to start thinking about the fuel run too as this will need doing at the same time.

Brake lines

Whilst I think about a couple of other tasks I thought I would look at the next 'big' item which is fitting the brake lines. The AK manual gives a good indication of where each of them should run, navigating the major chassis lines.

The key thing about bending this stuff is not to kink or pinch it. I thought about purchasing a brake pipe bending too but the metal is soft enough that with a bit if care it's not needed.

The two main rules are to use something to help form the bend. Aerosol cans from wd40, calliper paint etc plus round bar off cuts make perfect mandrels. There are tools but all the hand ones give is a form to bend around and a lever to apply force.

The other important part is to consider the impact of work hardening - so when bending do it slowly rather than faster as this will help the metal not to work harden giving it a much longer life.

I used masking tape to help locate the bend points from my previously made straight lines.

Others I know use plumbers solder as a pattern making device and then bend from that. So far I've found measure bend  and offer up as a repeated two step process is fine too.

Trial fit and I'm happy with that. Need to order some socket cap bolts to fit the pipe fittings to the chassis.

IVA requires these to be a maximum distance apart. I will be doing closer together to ensure safe anchoring and a pass on that front.

I will have to pop the engine out to the main line that runs to the rear as it's in the way of drilling fixings right now.

Shocking

Ready for a short, sharp, shock?

Actually it was more of a protracted long drawn out affair.

Now I have the nearside driveshaft camber sorted and the outer shaft nuts torqued up to 107lbs ft it seemed sensible to look at the coil over shock fitment.
 

For me this is when the chassis starts looking more like a car when the big springs are on.

Unlike the jag fitment which uses different option at the top the AK uses an extra shock shaft identical part to the one which passes through the middle of the wishbone for the bottom anchor point.
 

Once again though I come up against the evils of powder coat where you don't want it... Inside the upper shaft tube. Now wary of the vice like grip of this stuff I proceeded with caution cleaning the tube out thoroughly to the point where a few good taps with the rubber mallet and the upper shaft is in.
 

Then it's a case of just lining up the lower wishbone with the coilovers which I have set to a starting position of 20 clicks off full plus for the shocker and the bottom edge of the spring nut is 85mm from the centre of the shaft hole. This is Jon's starting config. No doubt I will be adjusting more as in go along one the springs have settled and I start looking at the ride height.

I haven't put the bolts on yet as I want to grease inside the bushes and the lower shaft itself as I forgot in my excitement of getting them on.

No schimfing here.

Ah yes, the Friday pun is back. Or something.

Right. Shimming time on the rear setup for hub camber. AK recommend -1/4 to 0 degrees rear camber. Measuring the offside it came in at + 1 with 2 shims so a bit more to be done there. 

Photo below shows testing adding some more with disc alignment shims as I run out of the camber ones. Order to wards now on its way.

Just enough room to do the bolts up.

On the nearside I went for 3 shims at the outset and hit the jackpot. With the top of the hub carrier supported 150mm from top chassis member directly above using a trolley jack the rear arm is at normal ride height. Measuring gives 0 degrees plumb.

Given I won't be racing around a track every weekend I'm happy with that.

I will double check with a more conventional camber gauge in due course -although this would appear to be accurate when calibrated against my spirit level.

And my wish came true!

Yes! Thankfully the nearside one was much much easier. Thanks again to Ed Ward getting parts through rapidly I was able to tackle the nearside wishbone that had me quaking for a few days after the previous experience.

Again the shaft carrier is wire locked once bolted on correctly.

I decided to take a more subtle approach of finding out where the problem areas were going to be before greasing up the small parts. The tricky bit was the front pivot shaft support in the chassis. But as well as using the ratchet strapping to help pull the diff where I wanted it I also had the trolley jack applying some lift from underneath to get the path as easy as possible.

Once I knew I had a better aligned run I then greased up all the washers etc and fitted the shaft.