Projects - Page 2 of 3 - Promotive Engineering

Every kid’s dream – a 935 K3!

November 23, 2016 by Promotive Leave a Comment

When I was a kid, my bedroom walls weren’t lined with posters of Pamela Anderson, they were lined with posters of the all conquering Porsche 935s. And ever since I have wanted one. Or more to the point, I needed one! Watching them breathe fire down the Mulsanne Straight at the Le Mans Classic a few years ago really didn’t help my need either…

Meanwhile, I have been wondering what to do with a car we affectionately call Cupcake, an ex-Porsche Cup racer. Being built on an early model shell that is in unbelievably good condition; and the ever increasing values of the long nose cars; the smart move would be to restore it back to standard. I have never been that smart, so I ordered some late 935 K3 panels and hunted around the workshop for the angle grinder…

Removing the existing 930S body kit was quite cathartic! I don’t know what Porsche was thinking when they came up with the slopenose body in 1981 – it has always been a bit embarrassing, it is like the ugly lovechild of a 944 and a 930 – and no one likes a 944! Then again, it could be argued that painting it a three layer pearl pink could also be considered a bit silly. I was young…

It was like Christmas came early when the kit turned up! It was pretty painless compared to some of the other kits I have ordered for customers. I had to sit the panels on the car to see how much work was ahead of me. As you can see from the photos – a lot!

The one piece nose is going to be pretty straight forward. Unfortunately the existing splitter isn’t a good fit so a new one and matching flat floor will need to be laid up. The rear is a bit more complicated. The panels aren’t too bad but I want a fit that is better than the average race car so it isn’t going to happen overnight. A 935 is 2 meters wide and in original form ran 19 x 16 inches wide wheels so it makes the existing 16 x 13 inch wide rear wheels look a bit silly. Heck, it looks like some really bad quality VW kit car at the moment! I better sort out some decent sized centre lock wheels. I really need some old school centrelock BBS wheels with the fans…

935-k3-mockup-side

Audi S1 E2 Group B Replica – update

November 15, 2016 by Promotive Leave a Comment

This project is moving along at a glacial pace… To be fair, there are still a few customer projects that were booked in before this one so I can’t really get stuck into it yet.

The shell has been stripped and shortened by about 320mm. That makes the wheelbase of these Group B replicas about an inch shorter than a short wheelbase / pre 1969 911! Scary! At the same time the windscreen angle needed to be changed by using the ‘A’ pillars from Audi 80 roof welded in at the firewall plenum, which in turn was chopped down and replaced with the period correct shape Kevlar roof and ‘C’ pillar section. Sadly (or not) we sacrificed an entire Audi 80 just the windscreen frame. The amount of parts being reused from the original the Quattro could be counted on one hand too, I guess the more parts that are sent metal recycling, the more collectable these things get!

The correct roof is actually wider at the top than the standard heavily raked Ur Quattro screen and roof so luckily everything lined up nicely once the frames were widened. The ‘B’ pillars also needed to be chopped down and made narrower to be more authentic, and the correct door frames were then grafted on to match the rake of the new roof. A great job if you think jigsaw puzzles that don’t have the correct shaped pieces are fun…

Next, an oversized centre tunnel was added to make roof for the hefty sequential gearbox, an exhaust system and water cooling lines for the rear mounted radiator. The rear floor was replaced by a sheet section and some temporary wheel tubs were added.

It is pretty exciting to have the shell recognisable as a car! I will have to hang the rest of the panels on it so they retain their shape, but the rollcage and fabricated strut towers are the next items on the substantial job list…

1957 Gaggia Monte Carlo Restoration

November 15, 2016 by Promotive Leave a Comment

This is not the normal type of project here, but copious amounts of coffee is absolutely critical to my thought process!

I have had this late 1950’s Gaggia Monte Carlo two group lever coffee machine sitting around begging to be restored for just too long. I recently I found the seals and parts that I have prevented me from using the machine, so I thought I would spend a little bit of time to give it a new life.

: The original heads in a sorry state after years of neglect!

: The frame was blasted and powdercoated. The boiler had previously been blasted and new elements installed.

: It was easier to machine new nuts than try and find original ones.

: The finished nuts next to the originals.

: TIG brazing the dints and pinholes in the heads.

: The first polish, almost ready for a copper coating before repolishing

: The parts as they came back from Pacific Plating. They look amazing!

: The pistons were hard chromed but one needed a thread repair which was achieved by welding a new base onto the rack.

: Dummy assembled (in more ways than one!) to test the fit with new seals and boiler control.

It is a sensational looking machine! It is almost done now, with a bit of tuning and a pair of original steam wands and a bakalite knob and an original indicator bezel – the coffee will flow once more!

Motorsports can be so frustrating!

November 9, 2016 by Promotive Leave a Comment

So, so frustrating!

Targa Tasmania was going so well for car 806 until an unfortunate overtaking accident left made a mess of the car…

After all sorts of delays with available panels and parts, I finally got the car back here with only three weeks to get it ready for the event, Targa High Country. While the panel shop did an amazing job of straightening the shell out (everything fitted and wheel aligned / corner weighted perfectly); it wasn’t just a case of bolting it all back together. On top of the normal pre rally prep and a couple of upgrades, there was fire damage to the wiring loom, impact damage on every corner where every bracket and part needed replacing or repairing, as well as repairs to the engine and exhaust, crack testing and inspections for the gearbox and drivetrain.

We got through the job list in the limited time available. The car even had time to get a new wrap job and a test. Even the air conditioning was re-gassed! I finally caught up with some sleep thinking we did a pretty good job!

That was until I got a call from the event… After all that work and late nights – the fuel pump randomly decided it was time to stop working! It wasn’t even that old! So frustrating – who would have picked that to fail!

And yes, I have CAD drawn up a new fuel tank top insert for a dual pump upgrade before the next rally…

Reverse Engineering with Ease (Relatively speaking)

September 10, 2016 by Promotive Leave a Comment

The 3D printer has been fantastic for prototyping and checking CAD parts before I send them to the CNC for production. It has saved countless hours on designing parts like the roller tip rockers for the Lycoming engine. Changing motion ratios and optimising the tip geometry couldn’t have been done easily or as quickly any other way without a complete and accurate 3D model of the cylinder and other critical parts.

The parts still needed to be created on CAD with no accurate reference to the original part. Until now! Parts like the standard Lycoming rocker couldn’t easily be measured with my digitising probe or the camera loaded into the CNC so I have been exploring other options…

Metrology grade 3D scanning can easily be outsourced these days but the time and cost of relying on other companies is just painful – I haven’t had much luck with either! After a bit of research and a few trials I settled on a fairly new release to the market which on specification seemed to fit my requirement nicely.

I haven’t had a huge amount of time to play with the scanner yet but the first results seem really promising, especially with the automated turntable. I scanned in the standard Lycoming rocker to see the quality of the model which made measuring the standard angles and dimensions really easy. As a test, I also scanned in one of my 3D printed roller tip rockers. I sent the resulting model to the printer to compare the scanned model with the original and amazingly, there were no real differences that could be measured with a vernier caliper! Pretty impressed with that! The advertised resolution drops off when scanning larger parts like body panels but I haven’t tried that yet.

I tried a twin plug 911 head that was lying around to see if my dreams of easily making a billet head were going to come true, but it seems there isn’t a lazy option with the complex geometries. The resolution is amazing with the texture camera. You can see every little surface mark, but I really need spend a bit more time with the scanning technique. It looks a lot easier in the sales video! What they don’t also tell you in the sales video is that after the initial purchase, you need to spend the equivalent cost of a car again on yet more software to make it easier to create the solid model from the scanned model so the scan is useful for actual reverse engineering. Otherwise it is only really good for making high resolution bobbleheads and simple changes to existing parts.

I know there are a few motorsport teams that are using this scanner now so it will be interesting to see how it works out for me!

It’s a bird, it’s a plane…

April 25, 2016 by Promotive Leave a Comment

The year is flying past at a great rate of knots! Something that is still not flying along at the moment is the plane project – but did finally reach a milestone over the long weekend!

Yep, the power assemblies were finally bolted on for the final time! Other than the bare cylinder and the rocker cover, there isn’t anything Lycoming in these jugs either. A mind-numbingly large amount of time has been spent designing, installing the custom valve train and machining the (really) high compression pistons. Even more time was spent on getting the porting right so that lazy air has an easier path in and out of the engine. It took a while but you can’t rush art…

The split plenum manifold and tuned length exhaust seems to have worked out quite nicely too. I am quite concerned about how loud and antisocial it is going to be… Anyway, at least it looks good – the photos really don’t do it justice at all.

There is no point getting too excited about hearing noise yet, there is still a bit of wiring and plumbing still to be completed, and the fiddly job of fabricating new cooling baffles. The next big job to tackle is to modify the Edge 540 cowl suit my cold air intake. And then remake it in carbon…

Porsche dyno testing

December 5, 2015 by Promotive Leave a Comment

It seems like I have been spending a lot of time testing fuels these days! I have tested the ETS Extra Max fuel in most of the standard late model Porsches to see what sort of gains can be made just by pouring in the oxygenated race fuel. The various Bosch ECUs respond well to the fuel and the gains have been at least 30hp at the wheels with no other changes made. On cars that have the ability to retune and add boost then the gains that can safely be made are significantly more! It is cheap power and great for track days…

996 Turbo Dyno Porsche 996 ETS Graph

Testing on the chassis dynos has been a great way to check the tune and show the relative gains to be made from the fuel but using a ‘rolling road’ can be a bit problematic. There are drivetrain and associated losses through the tyres, inconsistency with overheating tyre temperatures (particularly with race rubber), wheel spin and the electronic diff controls on some of the Porsche four wheel drive models just don’t get on particularly well with some dynos…

An increase in power is one thing, but what doesn’t don’t show on a dyno graph is the increased throttle response which gives that extra punch out of the corner, and sound of the engine is so much smoother!

I have been using my engine dyno to do a fair bit of comparison testing too. It is no secret that I have never been a fan of premium 98 fuel, the lack of consistency from the pump has always scared me. It is Ok on a car with a factory ECUs that have closed loop controls that wind back the timing when detonation is detected, but on highly strung engines that are used in competition – it is a bit like playing Russian Roulette. Using the repeatability of the my engine dyno, I did some back to back tests comparing P98 fuel to ETS Extra Max. The engine I used was a relatively standard air cooled 911 turbo engine. Like most 911 turbos, it doesn’t have enough airflow over the intercooler so has high inlet air temperatures, and it has the same problem with the oil cooling, particularly after a few laps at the track on a hot QLD summer. It is the sort of engine that is a bit scary on P98 with any reasonable amount of boost.

The graph below shows the runs from the two fuels. Obviously the line labelled ‘Hp(1)’ is P98 and ‘Hp’ is Extra Max. It is a pretty huge difference and the only change I made to the tune was trimming the fuel sites on the Motec M800 to make the lambda about the same. The blue line is MAP pressure so the engine is just running on waste gate pressure for this test.

The engine with a bit more boost. Unfortunately it is running out of airflow but it does have very conservative cams and heads…

ETS ExtraMax boost

And this isn’t the worlds most exciting video but here is the engine in action…

Ceramic Coating – bling with function!

November 24, 2015 by Promotive Leave a Comment

I have never really understood the appeal of chrome. It really only points out that the part hiding underneath is low tech, over weight and its only trump card is that the part is shiny. You could argue that it prevents corrosion on ferrous parts but there are a lot of better options.

One of those high performance options is cadmium plating which has all sorts of great additional properties such as prevention of galling and a neutral galvanic coupling when used with dissimilar materials. I guess that is why Porsche used it so much in the past and why it is still the coating of choice for aviation. Unfortunately is becoming more difficult and expensive to use.

One of my other favourite coatings is ceramic. As seen in the photos, it has a lot of bling to it but has the performance to match. It isn’t only for exhausts systems, I use it for other external parts like aluminium manifolds and internally on piston crowns, combustion chambers and valves to encourage more heat out the exhaust.

The photo of the valves above show one pair that is coated next to the uncoated spares. The beautiful swirl polish finish of the custom valves is gone but heat reduction into the valve is measurable. The intake valve is cooled by the intake charge so it is normal just to coat the combustion side. The exhaust valve has a harder time so coating both sides can be an advantage and take some heat away from the guides. The same goes for the pistons like the GT2 pistons pictured above except a dry film lubrication is applied to the skirts. The coatings on the pistons are such an advantage that I don’t build engines with out the coatings these days…

I just had to include a few photos of the Lycoming 540 cold air induction manifold I just made and had coated. The thing is a monster! It looks like a giant spider – well, a spider that only has six legs anyway… It has injector bosses for calibrated injectors to be fired by a Motec M1, as opposed to the ridiculously basic aviation injection that makes K-Jetronic look like something out of Star Trek; tapered tubes, bellmouths in the plenum and all of those little details that take ages to fabricate and aren’t really seen! The Lycoming cylinders are not crossflow so the exhaust is in very close proximity and the entire exhaust and intake manifolds are therefore coated. (The picture of the merge collectors above are for the same engine).

Another round of Golf…

November 10, 2015 by Promotive Leave a Comment

More pictures and less words this time…

I wanted to take some photos of the hidden parts of the classic rally Golf while it still looks half reasonable. There are plenty of hand made goodies underneath like the control arms and equal length driveshafts and associated bits. I guess I should have washed it before shooting the photos but after a special stage or two it won’t really matter.

The brakes are probably worth a shot too. It isn’t hard to work out which end is which on a front wheel drive car! These stoppers are about as big as I can fit sensibly fit under the Compomotive rally wheels. The massive front MCA struts make me smile every time I see them – you can’t get a better damper!