How I built the "Flying Brick"

Started by MD, August 29, 2011, 10:18:35 PM

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MD

It all started with an itch. Greg Summerville and I were sitting around his workshop dining table on a typical Saturday afternoon knocking back some wood smoke oven meat pies for lunch and listening to the Goons Show on radio. After nearly choking on my food from the jokes, we decided to settle down and just talk shop like guys who love cars always do. Pretty soon the subject turned to race and rally. It had been around 10 years since Greg gave up rallying and he felt as his life was going stale. Me on the other hand had never been racing but was also looking to recharge the batteries with some sort of new activity.

Before too long we looked at each other and said, why don't we go club racing with the Alfa boys? It took about two minutes to decide on the car and who was going to do what. A week later I bought a clapped 2 litre Alfetta sedan, put it into a corner of the workshop to give it is new home and the birth of the Flying Brick had commenced.

While Greg worked on earning a buck and finishing jobs that were headaches through the week, I soldiered on with doing all the goffer jobs like stripping the car down to its last nut and bolt. Removing all the sound deadening materials inside and out in preparation of fitting a roll cage and full seam welding. Installing re-inforced front sway bar mounts that usually break off with big bars.Fitting rear dedion strap fixings to limit suspension droop. Engine bay cross bracing mounts and a host of minor body improvements.

Before all this happened, I made a body rotisserie so we could fit the car body to it and work on it with ease. This proved to be a great asset for making the roll cage, seam welding and overall fabrication work. It was also used in the paint booth to thoroughly paint the car inside out and top to bottom –literally.

Of course panel defects were repaired along the way and some serious weight reduction was also done at this time as the photos will show.

My design for the roll cage made strong emphasis on the rear suspension as the transaxles do all their driving from the rear. Get this right and the front will be a lot easier to sort out. Under utilise this small advantage and you may as well be driving a front box car with a live axle. So fixing the roll cage to the rear inner guard as it most often is, is not the answer. The cage should be tied to either the spring bases or the damper towers and reinforced accordingly to prevent flexing of these areas.

Why did we choose a transaxle sedan of all things? Well, it is sightly less weight than the coupe by some references. It has a 100mm longer wheelbase so that it is less twitchy. More headroom. Much cheaper to buy and runs the same mechanicals and suspension. With speeds of around 160kph (debatable) at the end of the Lakeside main straight for most Alfas, the air drag of the box verses the wedge seemed almost irrelevant. However the main reason we settled on the transaxle was that most of the winning club cars at the time were 105's. None of the transaxles that were competing seemed to have been developed to their full potential and so the time was ripe to set cat amongst the pigeons and have a crack. So we did. Here's some pics.
To be continued...
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

MD

Continued photos..
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

MD

#2
..and some more.
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

MD

Last of this batch of photos.
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

scott.venables

Boy have I been looking forward to this thread!  Thanks for posting MD.

Cheers,
Scott

MD

Thanks fellas. Hopefully by the time the topic reaches the end, some inspiration will flow onto guys who are a bit tentative about starting a project of their own as we cover all aspects of this car.

I had a vision once that considered what an interesting experiment in Australia wide collaboration it would be if we all collectively contributed what we know to build an AROCA car of a certain capacity and class to challenge other clubs who support other makes in what might be called  "The Australian Auto Clubs Challenge". Love to see it happen in my lifetime to see how Alfa would fare.

Back to reality, stay tuned for other instalments as I have time.
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

MD

A couple of weeks later the body came back from the paint shop. Here we see the car taking some sort of shape and some clues to its eventual set up.

From the outset, I had a fixation that we had to retain the torsion bars otherwise to me it wasn't an Alfetta. We did give it coil overs as well to get the spring values up but that decision cost me an extra 14.5 kg of weight - something to keep in mind if you have the same puritanical views.

This body was eventually fitted up with acrylic windows all round except for the front screen. The headlights were just visual thing to allow more air flow into the engine bay and this proved to be too much of a good thing in later life for it but was eventually fixed I think.

The original fuel tank was retained as it had a perfect placement. Due to the removal of the rear divider, the filler neck and breather were fully encased for fire protection. The tank itself was modified by installing an in tank lift pump (VL Commodore) and a return line connection.

You will see that the front and rear bump stops were removed as the suspension only had 35mm travel. In race trim, the front rails were 80mm above the ground which made the car very low. Now this was part of the overall handling specs which we shall discuss in the suspension part of this topic. However, it was the biggest pain in the butt as it wouldn't go onto any hoist without first getting a lift up from an ultra low racing jack! And lets not talk about getting it onto a trailer. We needed 4.5 metre long ramps especially made to get it on and off the trailer. As they say, no gain without pain. Lesson here, if you want it low, be prepared for some issues.

The so called "air dam" was deliberately installed as a conversation piece. It had no other practical value whatsoever. It had supporters and others less than enthusiastic about it .With my sense of humour, I naturally had to give the 105 boys a bit of a rub up given all their wins and so I quickly named it my "105 nudge bar" and that's how the shit fight started..( as the joke goes) ;D ;D
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

MD

some additional detail.
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

MD

a bit more cause this is the only way I can cover the topic
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

MD

and to round off..

I will be covering the suspension next.
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

MD

Perhaps a list of the set up is as good as any approach followed by some photos that should be self explanatory.

·   Modified and adjustable roll centres front and rear
·   Inverted lower control arm ball joint.(ex Gemini) (needs 16" rims)
·   105 castor rod ball joint
·   SZ bushing to rear "A" frame
·   Adjustable watts links with rose joints
·   480lb Coil over Koni yellows together with 22mm torsion bars at the front. Total 600lbs.
·   420lb variable rate Springs at the rear and Koni yellow dampers
·   All dampers adjusted to match spring rates.
·   Modified bump steer geometry (about 80mm)
·   3.5* rear camber 0* toe
·   Hub conversion to 114.5mm PCD to facilitate much greater wheel selection
·   16x7 wheels, 35–ve  offset and fitted with 205x45x16 R series medium hardness tyres
·   No rear sway bar

I had envisaged a swanky adjustable front sway bar that would need a lot of experimentation to get the handling right. Before I did that  we fitted an original 22mm sway bar to get some idea of how much bar it needed. It turned out perfect straight out the of the box !! So it was pointless to do any more.
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

MD

Suspension continued..
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

MD

Continued some more..
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

pep105

Great thread MD

What a smorgasbord of Alfetta modification delights. Love the interesting and methodical approaches to the development of
the flying brick. Can only inspire others.

This is transaxle porn!  forget big naturals.com  ;)

As you were

Pep

Current
'74 GT 1600 Junior  (Currently under restoration)
'84 Alfetta GCL Sedan
'02 Vespa ET4 150
'05 GT 3.2
Past
'82 Fiat 131 Superbrava Mk II
'82 Alfetta GTV 2.0
'88 75 Twinspark
'80 Alfetta Sedan
'02 147 Twinspark

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Great thread- keep up the good work!
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