Alterantive RX8 housing exhaust port

Following on from my previous post, the steel exhaust port insert is great apart from sealing it to the existing liner. Tig welding was possible but definitely not a preferred option.

Next option tried was to pocket out the area where an exhaust port would normally exist and press in a new piece from which a new port could be machined. This option is very involved but worked well. Aside from getting the correct fit for the insert, the most technical part was generating the 3D milling program that blends the exhaust port from typical Mazda port shape at liner to full round profile at manifold mount face:

Rotary engines

After a long time with no progress on the 787B project and many other distractions, I'm finally back working on parts for it!

Right from the outset, the main issue for me (and many others) was fitting a V8 into the car where there should really be a four rotor engine. Fast forward to the present day and I'm now experimenting with rotary engines and the various build combinations that are possible. I have a 1985 Mazda RX7 that came complete with an engine and a load of spare engine parts to get the ball rolling.

I have rebuilt the 12A two rotor turbo engine in my RX7 and a few others now, and whilst everything was dismantled I decided to measure and draw up all relevant parts. Back when I started this project the four rotor seemed almost unachievable not to mention very expensive. Having seen more people building these engines now though , I decided to give it a go myself

In the last year or so since buying the RX7 I have carried out the following research and design work:
- Draw up all relevant Mazda OEM engine parts including eccentric shaft, rotors, stationary gears, counterweights, thrust bearing packages, rotor housings, end and middle plates etc. I picked up some RX8 engine part as well for comparison.
- Look into options for replacing worn out 12A housings, either by way of repair or creating new ones from donor 13B parts
- Peripheral porting experiments with worn out RX8 rotor housings.
- Draw up new designs for four rotor engine including eccentric shaft (5 piece), counterweights, main bearing housings, centre plate modification and direct oil feed system. I managed to gain access to a three rotor and four rotor shaft which I was able to measure up for reference.

Next on the list is to get together all the donor parts, and start machining the eccentric shaft now the material has turned up.

Here is a RX8 housing being machined to accept a steel exhaust sleeve:

New project. Mercedes 190 cosworth track car. This started as a simple restoration but is now going to be a rolling test bed for some new products I am designing. I have sorted a rear control arm kit that replaces all the rubber jointed links with adjustable rod end links. For the engine, I went down the road of recreating a guillotine throttle system but went the roller barrel throttle body route instead. The first revision designs for this are nearing completion.

I am also going to be analysing suspension performance enhancements. I have driven the car for many years on the standard setup. I have a set of bilstein shocks/struts to go on and then I want to develop some coilovers and chassis modifications with the aid of the knowledge I have gained from my current workplace. As a company we have been involved in the preparation of cars for rally and tarmac motorsport events, including winning WRC cars.

Here's a pic of the Mercedes after unbolting everything:

New project. Hillclimb car powered by a ZX10R engine. All parts designed by myself.

It's been a little while but some updates are in order.. Firstly, I am now working at a motorsport suspension and chassis design company. Unfortunately the group c replica is on hold at the moment. Replica body shells, 17" wheels and tyres, brakes and of course the necessary rotary powerplant add up to a fair bit of money that I do not have available right now. I want to complete the project but do it properly and as such it will have to wait for now. I have started on two projects that will allow me to develop some new products.

The first new project is the hillclimb car. I got the chance to buy a crashed ZX10R a few months ago. It was going very cheap as it would not start, electrical problems the most likely cause. With the bike back at home, I went through the on-board diagnosis procedure and located the problem to the ignition barrel sensor. A few days later a replacement arrived in the post and the bike fired up first time! I also came across a brilliant guy who has access to used race car parts. I then managed to pick up a set of F3 wheels with tyres and complete front brakes, all for a very reasonable price. The aim with the car is to keep it lightweight and simple. The bodywork will be far more easy to produce that the closed cockpit group c style car and will end up looking something like the Norma M20.

The second new project is the Mercedes 190 cosworth track car. I have had this car for a number of years, running it as a daily driver. I've taken it of daily duties now though and pulled the bodykit off a few weekends back to see the extent of the rust I spied bubbling at the bodykit edge. Nothing too bad was found underneath. It will require a bit of welding around the rear arches and near the front jacking points but all of it I will be able to carry out myself. The engine in the car is fantastic and feels totally indestructible but with the ageing bosch mechanical fuel injection it lacks the responsiveness of a more modern car. The handling was adequate but is clearly let down by the dozens of old, perished and well worn rubber bushes connecting the rear wheels to the body shell. Whilst working on a customers car the other day at work, I got thinking about sorting a car for myself. The Merc seemed the obvious answer. I've removed the rear subframe, bodykit and interior, found the extents of the rust which I will now repair and then rebuild the car using all the new parts I have designed.

Painting the spaceframe!

I spent a lot of time the weekend before last with my devoted Fiancee, sanding down the frame to remove all the surface rust that has built up. We then painted it with a red oxide primer just to prevent any further oxidation occurring. Although not complete it was nice to gain an insight into what it could look like in a finished state...





I've also stripped down the Audi engine to make sure all is ok internally and to see if there was anything I could leave off during installation into the chassis. It was interesting to see how advanced the engine is. It has a crank scraper, oil drains from the valley routed back the oil pump and a sump interface casting that I have found I will be able to remove completely, fabricating my own dry-sump system and losing around 40/50mm in engine height!

Progress update

I've been making more progress with the front suspension. I've built two wishbones, finished the upright/wishbone mounts and improved on the front suspension arrangement again.





One issue a had with machining the spherical bearing housings for the wishbones was the circlip groove. I do not have any internal grooving tools to hand so I simply machined the housings in two halves, TIG welded them together, and then machined the final bore. All seems ok so far as I've pressed the bearings in and out with no difficulty.

I was on the verge of getting my wheel centres machined up, but until I am 100% sure on the design of everything else in that area I've made a hub adaptor that positions a wheel with one of the original BBS centres fitted at the correct offset.

I had a trial fit of everything this weekend and everything is looking good. Picked up my new TIG welder too. Went for an AC/DC machine so I can fabricate my own fuel/oil tanks etc when the time comes. Next task is the newly designed pull-rod rockers. I've got the needle roller bearings and aluminium billets all ready to go. More updates coming soon....