Projects and Updates - Page 3 of 4 - Promotive Engineering

It’s a bird, it’s a plane…

April 25, 2016 by Promotive

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

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…

https://youtu.be/O6oYyzDm1aA

Ceramic Coating – bling with function!

November 24, 2015 by Promotive

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

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!

GT2 v2.0…

July 6, 2015 by Promotive

The GT2 is progressing. Slowly. It looks like it is still only half a car, but it will be twice the car it was…

Unfortunately, the panels that we ordered were the worst quality I have come across in twenty years so a considerable amount of time has had to be spent on getting them to fit. I really want to make the rear panels clip off in one piece but I am behind schedule already so I cant deviate from the brief… At least the front is mainly fitted up and I am just need to keep the CNC running to make all of the little brackets and smaller parts.

While the rear firewall and panels are not yet finally mounted, it is easier to do the plumbing and mount the suspension. The rear links will be fitted in the next week so the new engine can be fitted and the turbo manifolds for the EFR turbos fabricated. The intercooler will be fed by the massive air scoop that was used previously so that can be fitted at the same time. The engine can be then dynoed and fitted…

There is still a few long days ahead before it looks like a car again!

Dyno upgrades

July 2, 2015 by Promotive

I have been busy lately on a few big builds and have managed to find some time to do some upgrades to the engine dyno that I have been wanting to do for too long. While some of the upgrades are purely practical and allow engine changes to be quicker, I have also added significant over capacity to the cooling system to engine temperatures can be optimised.

I have become really interested in the fuel testing lately and comparing different race fuels. I have added a flex fuel sensor to the dyno now which show how the ethanol content some of the cheaper competitors race fuels have and the consistency (or lack thereof!) ! It is a cheap way for them to increase knock resistance but it isn’t the best way of producing power…

I have upgraded the knock sensing in the cell as well. In addition to the two channel Vipec knock amplifier and headset, I have added a dedicated vibration sensing module. It is now easier to fine tune the knock sensors on a setup so there is less false readings and make it easier and faster to setup individual cylinder tuning. The new system will also analyse the vibration signature of an engine over time (FFT) and will show well balanced the engine is and the point of the imbalance. By looking at the spectral analysis you can distinguish the imbalance from a weak cylinder, a clutch or the cooling fan etc. Cool stuff!

Just need a more room on the console for all the readouts and instrumentation now! Maybe a lounge chair as well.

The Rally Golf…

June 30, 2015 by Promotive

Normally only 911s are allowed into the workshop. I have made a couple of exceptions lately, one being the short wheelbase Group B Audi replica and the other is the classic rally Golf Mk1 that is destined to run in the Australian Classic Rally Championship. This has been a massive ground up build which I will elaborate on in a later post and actually take some decent photos…

The exciting news is that the Golf is finally alive! I am yet to tune the massive 50mm carbies (- yes old fashioned carburettors!) but the induction noise of this engine is amazing. It should be too considering how ridiculously high compression is, and of course it is designed to run on the ETS Extra Max race fuel.

I am sure the sound of this car will be confused for a big bore sports bike in the distance because the ratios in the dog box are so close…

With just a few final touches to be made, the test day is not too far away!

Feeling Blue. Not with this RS Tribute!

May 4, 2015 by Promotive

This photo will be recognisable from the main page of my website perhaps. The wheels on this RS Tribute really were so spectacular that my (very) armature photography skills couldn’t really capture the gloriousness of the detail when seen in person. They really set off what turned out to be a very tidy 911!

The wheels were 15 inch Braid RSR style wheels but these ones are not the standard finish as supplied by Braid. They were stripped, anodised and dipped in paint to create perfect paint edges and then the lips were polished to give the final touch. I think they have turned out nicer than the Harvey Weidman wheels… Of course, the venerable Michelin TB15 tyres completed the look.

The sad thing about having such nice wheels is that the stunning RSR replica brakes were hidden away! I completely rebuilt the suspension and vapour blasted the arms before replating everything, fabricating some RSR style sway bars and fitting the 2.8RSR brake kit from Zuffenhaus. The calipers are stunning! The shocks were revalved to match the new spring rates and the result was a bucket full of fun!

A Tilton pedal box was mounted onto a reach adjustable mount so the correct pedal position could be found and the brake balance could be perfected. The pedal box was hidden under a custom carpet set and everything that a modicum of shine was powdercoated satin black.

The aim of this car was to have a fun toy for the weekend but it also turned heads everywhere it went!

Mexico Blue is such a striking colour!

KnockLink

April 7, 2015 by Promotive

Every now and then I come across a cool little tuning tool that actually works.

I have been using a Vipec knock ear on the dyno for a few years now. They have an algorithm that filters out background noise quite accurately. When used with a matching Vipec ECU, they have a similar system to Motec in that they listen to a tuned frequency within a specified window. It takes a fair bit of time to set either system up but it is the only way to set up accurate individual cylinder knock control.

The new little KnockLink is made by Link who also manufacture the Vipec ECUs. This great little light is really simple. You just need to mount a suitable knock sensor (or use the existing ones on 993 or later engines) and fasten the light with the supplied mount. The wiring is simple too. Two wires go to the sensor plus 12V power and earth. It self calibrates on engine start up and will flash to warn if knock is present. It won’t adjust the timing but at least you will see that you have a problem!

Very handy for early model 911s that aren’t running fuel injection or good quality fuel!

I have a few of these in stock now. The RRP is $275. I can also supply a suitable knock sensor.