A little bit of an optimisation, someday soon I may get around to start building it.
Planning an update to the exhaust, starting early in the morning or coming back late is a bit of an issue. Dispite the sound passing SVA it’s a tad disruptive. Also on long trips at 50mph you get quite a bit of resonance.
This setup using Varex X-Force back boxes gives the best of both. Open it up and it’s a straight through perforated style muffler same as the magnaflow boxes on there now and when closed the sound is reduced to stock or lower levels.
Pipes by Jetex same as the current exhaust – great quality and lots of choice.
V band clamps from eBay, will have to see how the quality lasts on the clamps.
Example of this type of system on a Ford 289 small block V8 (Original marked in Video had two tiny bullet mufflers and it literally made your ears ring after 10mins of driving, was also a two pipe system. New varex setup also added an x pipe)
Now I just need to find time to build the new one! Doing a bit of planning in Autodesk Fusion 360 – which is aviable for free if you’re a hobbist, well worth a look if you’re into playing with CAD.
This shows some jetex parts to bridge the height differene between the exhaust run and back box height:
Turned a suitable bushing on the lathe for the clutch to pivot around on to the pedal:
Assemebled and in place, the 3d printed part feels very solid. First time I bolted up the pipe to the front the banjo joint didn’t seal up enough – lots of fluid everywhere… added an extra washer and it’s all good now:
The clutch is now quite similar to how it was originally, but without lots of movement of the master cylinder. It’s now much nicer to drive again.
Engine service has made a big difference, it’s a lot smoother and quieter again now. Setting the valve clearances as reduced the M20 rattle by quite a lot.
I can also recommend the ATE pads, they bite much better than the jurid ones that were on there.
It was also a good opportunity to re-glue a lot of carpet in the footwell where the spray mount glue had failed over the years.
A few minor things need doing before the MOT – one ball joints rubber cover is rotting away and the upper control arms need some extra large washers adding on the inside – there’s a bit of movement on the drivers side.
I had help today – nothing like being upside down with your feet in the air in the foot well with a cat wandering over you:
3rd design set for the clutch bracket. As we ran out of ColorFabb HT filament it gave me a few more days to consider the design so I’ve revised some angles:
All 3 versions, note the middle one didnt finish printing:
Extra support structures
Clearance for the fluid fill. You can see the layers don’t look very smooth – that’s by design as it makes the print stronger by having thicker layers. For a display piece we’d print with much finer layers that which would look a lot smoother. As this is a functional piece you can’t see it doesn’t matter.
Watch the print!
Ran out of ColorFabb HT with a bit to go on the print unfortunately, however this is a great strength test piece. It’s very strong already with 2/3 of the triangulation structure missing. This part will work in the car, no need to remake in metal.
I may make a few more design tweaks before starting another print. More material is due at the end of the week.
Mike on mad about kit cars brought up a point about pedal / master cylinder angle. The standard placement moves the piston in at an angle which can cause failure – I’m going to check this on the car make sure the master cylinder won’t get damaged.
V2 clutch bracket with room for pipe and holes to bolt to the top of the scuttle.
If this were printable as usable part then I’ve done an extra version with more structure and cleaned up edges – there would probably need to be more material to the front mount point as well:
Updated: going to try a 3D printed one using ColorFabb HT
Added a load of extra structure to strengthen the part were it’s bolted.
The print is sliced like this giving the most strength in the direction the force of pushing the clutch would go through the part.:
The yellow lines are the movement of the print head, the black cylinder is the print head, it’s shown with the top 1/4 left to go, the corrigated stuff is support material – without it gravity can take effect and the runs of plastic can sag. It’s set to print with 100% fill so that it’s as strong as it can be. The prototype had less fill which saves both print time and plastic but is not as strong.
10 hours into the print:
3D model of the clutch bracket prototype made with Autodesk 123D
Printing the object on an Ultimaker 2+
The 3D printed object, which is incredibly accurate:
Clutch master fits on the 3D prototype print without any adjustments needed. The design needs a bit more clearance for the fluid feed pipe and it needs to be extended forward to make use of my second scuttle mount hole. I can probably add more re-enforcement where there is room.
Fits into the car too!
Added a hole for the scuttle mount and tested the spacing for the pedal fit.
A few cm forward of it is the second mount hole so the bracket can be lengthened to make use of it.
Next step is to refine the design and create a metal version.
Since first installing the brakes a spring has been missing off one of the pads which means the passenger side calliper rattles. I decided to switch from the jurid to ATE pads – the ATE’s bite a bit better initally than the jurids – something I’ve found on my daily drivers. Also the ATE pads are OE for E46 / E9x.
A few bits of rust, here under the drivers door:
Chipped off, brushed and some rust remedy:
Sprayed with rollbar and chassis paint, you can see the hole in powder coat but I’d rather this than have the surface rust carry on creeping:
The wing mounts had also started to rust, so took these off while the wheels were off for the pad change. Also cleaned up any chips in the powder coat on the front suspension:
Refreshed with new nuts and bolts:
3D part has also finished printing, need to how this fits:
The clutch slave failed – not sure why, perhapse the master cylinder was pushing too much fluid into it. The reason is not so important, I’ve decided to use the BMW master cylinder as this will be matched to the slave. Unfortunatly the original design for the clutch attachment is very poor – the whole pedal box twists.
Therefore I’ve started protyping a new bracket design that will be a strong mount for the master cylinder with a bracket the bolts up through the top of the scuttle – already re-enforced for the pervious alternative clutch arrangment.
I’ll 3D print this bracket for test fitting and if it works OK I’ll try to recreate this in aluminum.
A couple more hours: