Time for a "freshen-up" of our 1000TC

[pheyden]

My helper had some extra time, so I set him with the project of installing new polycarbonate rear and side windows. I made them a bit thicker this time, so that they approximate the thickness of the original glass.

rear window new.jpg (58.11 KiB) Viewed 555 times

side window new.jpg (55.44 KiB) Viewed 554 times

I placed a number of "aircraft" type window vents in the top edge of the window to help depressurize the inside of the car when it is run with open door windows, as is required for many clubs in the USA. In Europe, where you can run door windows, the door windows will have window vents that look just like the ones in the rear side windows. These can be rotated forward to catch fresh air.

[RaceSport]

I take it you have to use a webbing over the window apeture then to stop your off/side arm flailing out in the event of an accident..ie a roll for instance!
Why does this rule apply?
To stop you baking in the car in your climate perhaps!

Causes a bit of aerodynamic drag i should think also!

Yours David L

[pheyden]

Yes,

I will be installing a window net, and I also use arm restraints (as in a formula car).

It is a safety thing. They want course marshals to be able to reach into the car without having to deal with a window in place.

Yes some air is trapped, but I have yet to install the wind wings (which will help)and that is why there are vents on the rear and side windows.

Paul

[pheyden]

In between customer work and fixing machine equipment I had an opportunity to install the "replacement" wind wing windows in the doors. Normally these would be glass and have a rather heavy metal frame. This Lexan version of the window weighs in at 60 grams as compared to 500+ grams for the glass unit.

New windwing.jpg (59.25 KiB) Viewed 499 times

I also added a small 'rotating' vent to the windwing. This can be closed if required, but in the open position provides some air flow to help in defogging the windshield on a rainy/damp day.

I found an interesting way to attach the window to the door. I used what are referred to in the book-binding industry as "binding bolts". These are a male and female bolt that threads together. On the outside is a screwdriver slot and in the other side of the window is just a rounded boss. These are also sometimes referred as "sex bolts", because of the way that they engage. I found some make of aluminium and they worked perfectly for this Lexan window installation. If required the window can he easily and quickly removed, unlike with rivets which have to be drilled out.

[pheyden]

My co-worker also finished putting in the remainder of the roll cage. I can now finish off the final part of the electrical installation.

The next job is to reinstall the aluminum floor plating under the driver's feet and the driver's seat. I would like very much to find one of the original 1000TC seats and install in on the passenger side. When I did this refit of the car I moved most everything out of the passenger footwell so that on race weekends when they have "drive arounds" for visitors, I could quickly fit the extra seat and give some kids a couple of laps of the circuit.

I also purchased all of the material to make the "suface plate" for the measurement of the suspension system. The plan is to put down three 4 x 8 sheets of MDF, making a 8 x 12 ft base. I checked the floor with a laser level today and its remarkably level. The plan is to paint the MDF before putting it down, to provide a water resistant surface, that can be easily kept clean. After it is laid down I plan on putting aluminum angle on all of the edges to protect the surface and to tie the three sections together.

The vehicle will be positioned "above" the surface plate on concrete blocks. These blocks are 45mm thick and I plan to use 5 of them stacked on top of each other at each wheel. Then the final block will be a granite block 25mm in thickness. This will put the car about 300mm from the ground and make taking measurements much easier.

In place of the four wheels/tires I will machine up 4 "hub plates". These have a 98mm bolt pattern so that they can be attached to the wheel hub at each corner of the car. The bottom edge of the 15mm thick plates will have to roller bearings that roll in a lateral direction. This allows the car to be raised and lowered without the problems associated with tire contact patch friction and travel.

While I will certainly use this layout to make all of the alignment of the new suspension easier, I also plan to record a 3D data set for all of the suspension points of the Fiat 600 chassis. By doing this, and then entering it into a 3D suspension design package, changes in the suspension can be modeled to see what effect (positive or negative) a proposed change might make. I have been wanting to do this for a couple of years, since buying the modeling software package, but never had the opportunity to do all of the digitization.

The MDF surface becomes the "horizontal" datum with all points recorded as a point above the datum. The front axle centerline will become the transverse datum, and the centerline of the vehicle is the longitudinal datum of the car. All measurements are noted as either positive (+) or negative (-) depending on which side of the datum line they appear. The horizontal datum will only have positive numbers, but the other two datums will have positive and negative numbers. As such, the right, forward inner end of the upper a-arm will have three identities. First it will be "x" millimeters above (+) the horizontal datum. Second it will be "x" millemeters to the right (+) of the longitudinal datum. Third, it will be "x" millimeters forward (+) of the front axle centerline. So each of the important locations of the entire suspension will be "located" within the 3D model.

Photos to come when available.

[pheyden]

Well, I would not believe it had I not seen it myself. The car actually sitting on tires back on the ground (well almost ground). Here is the chassis alignment platform that I described in the previous post.

Car on Platform1.jpg (55.57 KiB) Viewed 486 times

The platform is very flat with less than .5 degree of inclination from longitudinally and absolutely flat in the tranverse datum. Here I have a portable laser set up to check the "rake" of the chassis. Just straight off the jack stands the rear suspension is about 1.5 inches lower than before, but has only two degrees of negative camber. At the moment the front of the car is too high, but I have not added all of the lead weights in the driver's seat to make up for the driver, or the weight in the luggage compartment to make up for the 60 lbs (27 kilo) of fuel. Once this is done the front should settle and then I can reset the chassis. I would like to lower the car another 0.5-0.75 inches (12-18mm) and then have a small amount of rake, so that the front is slightly lower than the rear.

Car on Platform2.jpg (56.96 KiB) Viewed 489 times

The front suspension will be the first place that we start. At the moment the ride height and the camber in the front are not equal. This is not surprizing as many of the parts on the front of the car have been modified or renewed.

I will start out by first determining the centerline of the car and then establishing the front axle location at 90 degrees to the centerline. Once we have the lower a-arms so that they are equidistant from the centerline (longitudinal axis), then we can adjust the upper a-arm to give us the caster that we want. Once the caster is established then I want to double check the amount of negative camber and then finally set the toe-in.

Having accurately established the front axle location, the next thing to do is to measure the vehicle track in the rear and to adjust the trailing arms so that the vehicle wheelbase is precisely 2 meter. This is the homologated wheelbase for this chassis. It is interesting to note that with fully adjustable front and rear suspension you "could" lengthen the wheelbase slightly (thereby also changing the front / rear weight distribution) to put slightly more weight on the front axle. Once the wheelbase and track are established I would propose to do cross-chassis measurements to double check the results.

After all of these adjustments have been made, then attention then turns to documenting all of the suspension point locations as described in my earlier post.

[pheyden]

One step further. The car is now up on its platforms.

Car on setup blocks.jpg (50.06 KiB) Viewed 473 times

As I do not have a lift, this was the most convenient way of getting the car up in the air far enough to make the required adjustments and measurements. Under each wheel are two linoleum tiles with grease between them. This allows the car to settle to it's normal settings without having to roll it back-and-forth. At the front this also acts as turning plates to allow caster to be measured.

[evannice]

Paul, that is a fascinating approach. I look forward to reading how this works out!

Eric

[pheyden]

Evan,

Well, for an expenditure of about $30.00 I have a system where I can level the flatforms and have turning plates in the bargain.

Now that the platforms are leveled, and weight equivalent to the driver, fuel load etc. has been added to the car. The next thing is to bring the tires up to running pressures. Next we established the centerline of the front cross-member (chassis X axis) and aligned the lower a-arms so that this axis runs through the middle of the lower kingpin housing attachment or the a-arm. We now know that the lower a-arms on both sides are aligned to the cross-member. The actual front axle center-line will lie slightly behind this X-axis, due to kingpin inclination and caster. We next checked the caster of both front uprights and it was adjusted for - 7 degrees.

Next, I will use a weight checker to measure the corner weights of the car. I will put a photo of the process here as soon as this is done (and I rebuild the weight checker which had a hydraulic fault). I am hopeful that I can introduce some small amount of rake in the car, for aerodynamic purposes, however if this upsets the weight distribution and balance too greatly, then I will settle for a good setup.

My co-worker has already transferred the x-axis datum to the floor under the car. Similarly he established the vehicle center-line for chassis and transferred this to the floor under the car (the Z datum). The floor itself is the Y datum and represents a reference horizontal surface. Hence a point where the X and Z datums intersect, on the Y datum would be noted as X=0,Z=0,Y=0. The point for the attachment of the ends of the anti-roll bar might be as follows:

X=+406mm, Z=-14, Y=(total height - pad height) +100mm (Left side of bar)
X=-406mm, Z=-14, Y= (total height - pad height) +100mm (right side of bar)

As you can see the only change was in the X dimension, as it denotes the distance from the center-line of the car. This same method will be used to digitize each critical point on the chassis and suspension. Then using a program called SusProg3D all of these points will be entered. This will allow us to model the movement of the suspension in software.

After having aligned the lower front a-arms, I decided to do a quick check to see how far off the wheel base of the vehicle might be off. After all, a car that has been raced for over 20 years might be a bit off. Surprisingly, just using a tape measure, it measured within .2cm side-to-side and within .5mm of the specified 2 meter wheelbase. When we get to aligning the new tubolare trailing arms, we should be able to get this right on the money as it is suspended in adjustable joints.

Stay tuned for more reports as we work through all of the steps of setting up the chassis and suspension.

[pheyden]

More progress to report. I received my cylinder head back from the porting shop this afternoon.

New Head 2010.jpg (45.52 KiB) Viewed 405 times

New combustion chamber 2010.jpg (45.75 KiB) Viewed 400 times

I decided to use special Ampco copper seats this time around. They sure do look good. You will notice that the guides are for the new 5mm stem valves which are 31.45 and 27.5mm respectively. This is the largest valve that I feel comfortable with.

The chamber is like the original Fiat 850 chamber and has a volume, with the 0.040 thick steel multi-layer head gasket, of around 19cc. This makes the compression ratio around 13:1.

I have also chosen to use lifters which are fashioned after the TCR lifter. Here the push rod seat has been moved from the bottom of the lifter body to the top of the lifter body. In the TCR implementation it was done this way because of the acute angles that were required to make the valve train in this head work.

TCR lifter.jpg (36.2 KiB) Viewed 399 times

Using this lifter has the following effects. 1) The lifter does not fill up with oil. 2) The associated pushrod is 35mm shorter, making it both lighter and 1.7 times stiffer than the longer pushrod.

2010pushrodcomp.jpg (44.73 KiB) Viewed 318 times

To further decrease the parasitic losses associated with the push rod bores, these will be enlarged and bronze inserts pressed in. These bronze inserts will be relieved internally to present a smaller overall friction area for the lifter, which will be isotropically polished and DLC coated. One area that I am still investigating is whether to make a new lifter, with a head that is 2.5mm larger in diameter than standard. This would allow even more aggressive cam profiles, perhaps even with asymmetrical lobe configurations. These would not necessarily have more lift, but would open the valve quicker, keep it at maximum lift, and then have a much more gentle closing ramp to make sure that there was not valve bounce. In total this would increase the overall area under the curve.

Stay tuned for more reports.

[jovan_abarth]

Paul It looks great! Just continue with this pace and your TCR will shine in full brightness!
Only if you can put your images bigger or send me a email or Skype ..

Best regards,
Jovan

[pheyden]

This last weekend I was able to install the new axle assemblies in the new trailing arms, and do the final fitting of the lightened CV joint. These special 94mm CV joints have had a large proportion of the material (weight) removed.

lightened CV joints.jpg (44.32 KiB) Viewed 353 times

lightened CV joints2.jpg (48.44 KiB) Viewed 353 times

In the following photograph you can see that the suspension is sitting very low at the moment. This confirms what we found when we measured the rake of the car. The rear at the moment has -4 degrees camber so I will probably raise the rear slightly.

lightened CV joints3.jpg (49.98 KiB) Viewed 353 times

I am keeping true to my mantra of "lower rear weight" in almost all of the modifications that I am working with. The lightened CV joints are just another example or every little bit counting. An added benefit is that it lowered the "unsprung" weight of the rear suspension.

Keeping that same idea in mind, I have made inquiries about casting the next batch of PBS 2-piece sumps, and the 3-piece wheeel centers, in magnesium, rather than aluminium. The magnesium oil sump should save about 5-6 lbs and the magnesium wheel centers are 2 lbs lighter each. That is another 8 pounds saved.

[pheyden]

2010head1.jpg (53.06 KiB) Viewed 315 times

I started putting together the rocker arm assembly for the new motor today. This utilizes the hard-chrome plated shaft and a full set of aluminum roller tipped rockers.

2010head2.jpg (52.6 KiB) Viewed 314 times

2010head3.jpg (56.2 KiB) Viewed 316 times

In between rocker arm pairs is an aluminum spacer. There should be about 1mm of total end play for two rockers and a bush, so as to keep then rockers from locking up when then get hot and expand. Standard adjusters are used standard lock nuts for the moment. I am working on some lighter weight lock nuts for the future.

These photos also show the 5mm stem valves and associated components. This means smaller, lighter springs, titanium retainers and cotters. Overall the weight of the components on the valve side of the rocker arm has been reduced by 34%. The aluminum rocker arms is not any lighter than the standard steel unit, because of the volume of material required. The roller tip does reduce the friction component at the tip-to-valve stem interface.

[pheyden]

After having trial fit all the components, I am now on the final assembly of the motor.

The new pistons for this engine build are 13.2:1 compression.

New block 13.1 pistons.jpg (56.87 KiB) Viewed 206 times

These pistons started life as 13.5:1 pistons, but due to the reduced size of the combustions chamber the tops had to modified to get the compression down. All rings have been lapped and set to 0.011 inch (.28mm) end gap. The pistons are 0.003 below deck, so with the 0.032 (.8mm) thick head gasket, this will give a 0.035 inch (.89mm)squish distance. All edges of the dome have been contoured to minimize flame propagation delays. This particular block had already been retrofitted with 10mm head studs, so I will leave this as-is. At 8000 RPM there is approximately 0.015 inch (0.4mm) of rod stretch/crankshaft deflection, so the squish distance will actually be more like 0.020 inch (.5mm)

Crank scraper.jpg (56.67 KiB) Viewed 206 times

The bottom end is an Abarth 229 crankshaft with reworked Fiat 850 rods and ARP bolts. This is an engine that was run in 2004 and the 850 rods were in good condition, so there was no reason not to use them. You will also see the "crankshaft scraper" in this photo. This is installed at the pan rail and strips the oil rotating around the crankshaft and deposits it the bottom of the oil pan. You will also note that there is no oil pump, oil pump drive or distributor. I plan on using an external oil pump (belt driven) so that I can play around with oil pressures and flow more easily. As far as spark, I have two options. I can run a distributgor off the front of the cam chain housing, or use a distributorless system with a crankshaft impulse sensor, whichever is allowed. This also allows the valve cover to be more easily removed for valve adjustments.

Front chain cover.jpg (71.95 KiB) Viewed 207 times

The last photo shows the Gilmer belt drive extension for the external oil pump.

In the next installment I will work through the installation of the camshaft gear drive assembly and the distributor gear drive.

[pheyden]

In this next installment I started out by fitting the new camshaft and TCR style lifters. As there is no oil pump, or distributor. in the conventional location, no oil pump drive shaft is required. This also meant that careful attention had to be paid to camshaft end play, as the only thing that would control this is the rear cam bearing.

Once this was adjusted I could do the final installation of the camshaft gear drive and "piggy-back" distributor drive. The distributor drive is made up of two small helical gears, one attached to a modified VW Type 1 distributor and the other to the end of the camshaft.

Gear.tacho drive.jpg (47.48 KiB) Viewed 188 times

Next I prepared and mounted the drive cover and the crankshaft drive assembly to handle the alternator belt, oilpump Gilmer belt, and ignition impulse sensor.

Crankshaft sensor.jpg (48.73 KiB) Viewed 188 times

The engine will have two different ignitions systems. For the most part I will use an ECU based ignition system, with as "wasted spark" dual coil arrangement, that uses a crankshaft mounted trigger as shown in the following photo. The ECU will control how much ignitions advance is applied to the motor. In addition, the ECU also get water temperature, inlet temperature and throttle position information which it can use to further modify ignition advance accordingly. At some time in the future I would like to also include a "knock sensor" to detect early onset of detonation. While this is much advanced over a distributor, there is nothing that can be done to control the amount of fuel the motor gets, other than normal carburetor adjustments.

In such cases where the organizing club will not allow me to run the above ignition system, the engine will also car a conventional distributor. This is mounted as in the TCR and gets it away from the cylinder head. This makes doing valve adjustments a whole lot easier,

TCR Style distributor drive.jpg (47.87 KiB) Viewed 185 times

I took the time to mock up the head so that I could check to make sure that all of the ancillaries that will mount on it would fit without any problem.

Inlet 1.jpg (50.18 KiB) Viewed 188 times

Here you see the head mounted with the intake manifold and the carburetor adapters, ready for the Keihin carburetors. I will probably put these back together this weekend. The carburetors received some updates and a thorough overhaul. Here you can also see the plumbing associated with the reverse flow cooling. The next photo shows the inlet to the inverted cooling. Water enters the engine here and exits where the standard water pump would normally go.

Reverse flow cooling manifold.jpg (50.88 KiB) Viewed 188 times

Finally, I mounted the exhaust manifold to make sure that it does not foul the drive at the front of the motor.

coil box on Valve cover.jpg (48.58 KiB) Viewed 187 times

One of the last pieces of the puzzle is to mount the external oil pump and the bottom half of the oil sump. Because there is no internal pump, I have modified the sump so that the pick-up sits in the same location but routes to the side of the pan, where there is an AN-10 connection to the pump.

More to come.......