584 replies to this topic

[JDWhiteWRX]

I installed solid steering rack bushings from Diftech yesterday. I don't want any rubber bushings in this car.

 

[JDWhiteWRX]

Ok mega update time! this work has been going on over the past few weeks but I was saving it for one big post.

 

The steering rack is finally mounted in the chassis, here is the process...

 

First I wanted to have the ability to raise or lower the steering rack vertically just like the inner pivots on my control arms. This will allow me to fine tune the bump steer and also adjust the bump steer if I choose to move my control arms up or down.

To do this I would need some large and long bolts and something strong to mount then to.  

 

Materials cut to size for the mounts

 

 

Tacked together

 

 

Fully welded

 

 

How they mount to the rack

 

 

Then I decided to cut the frame rails further back to line up with the upper control arm mounts

 

 

 

Cut out some end caps using CAD from 3mm plate.

 

 

Welded the end caps on using Tig.

 

 

Then I created a bit of a jig to align the steering rack with the existing lower control arm mounts.

 

 

Then it was just a matter of cutting and notching some tube to connect the frame rails to the steering rack. I wanted to make the steering rack removable too so the engine could come out more easily. This required some extra work and captive nuts.

 

 

 

 

 

So these bits of tube can bolt together

 

 

Then the part of the tube with the captive nut inside was welded to the frame rail

 

 

Then it was just a matter of some paint and bolt it all together.

 

 

Looking at the detail you can see how the rack can be moved up and down. Some spacers will be required. Note the rack now has solid bushings too.

 

 

 

 

I've tried to keep the design as simple and light weight as possible, I am kind of using the steering rack as a large brace to stiffen up the front end some more. I do have plans to add some kind of a vertical x-brace that can be bolted on to tie the whole front end together but I need to finish mounting my oil pump first so I know what space I have to work with.

 

As it is now though the steering rack is mounted very rigid as one mounting face is in the horizontal plane and the other is in the vertical.

[El_Freddo]

Looks good as always Joel!

You wouldn’t add another piece of pipe between the two mount points on the rack? That would eliminate the stress no the rack itself being partly used as a brace like you said.

I bet that took a long time to sort out, like everything else in this build!

Cheers

Bennie

[RX25SE]

Sweet update!

This is really coming along nicely.

 

 

 

 

As it is now though the steering rack is mounted very rigid as one mounting face is in the horizontal plane and the other is in the vertical.

 

 

So no need to triangulate the rack mounting arms?

[JDWhiteWRX]

Yes I will be adding more bracing to the rack but I need to mount some other stuff first to make sure I don't run into any clearance issues.

[El_Freddo]

Yes I will be adding more bracing to the rack but I need to mount some other stuff first to make sure I don't run into any clearance issues.

Should’ve known!

Why we doubt you I don’t know...

Cheers

Bennie

[allpaw4]

Nice work! This is amazing. Shows what some CAD and a bit of skill with a welder can produce! Can't wait for the next update!

Cheers,
Ben

[JDWhiteWRX]

I have put some panels back on the car so that I can measure up the available space for the cooling package.

 

 

It's nice to see it like this, almost looks like a car again.

 

The amount of space in front of the engine is very good. I want to try and do a side by side arrangement for the intercooler and radiator if possible, if not then stacked will be good too.

 

This is just an old radiator from an Impreza for mock up purposes only.

 

 

The airflow will be ducted in through the bumper and exit out the bonnet (hood). Entry and exit about 1/3 the size of the cooling package I believe is best practice?

 

 

I have also received and installed a large shipment of parts from TracTuff in the USA. Not everything is shown in the photos, some of it won't go in until later.

 

Water pump delete with integrated alternator bracket

 

 

I'm using a small D-series alternator but I might need something more powerful eventually.

 

 

This housing cleans up the back of the engine and directs the radiator hose in a more favorable orientation for a RWD car.

 

 

This one deletes the water bypass since it is no longer required with an electric water pump.

 

 

These smaller fittings give me a place to remote mount my oil temperature and pressure sensor and provide a water feed for the turbo.

The larger fitting was part of my dry sump kit.

 

[RX25SE]

Looking really good!!

What is the output of that alternator? I can't imagine this car needing all that much current to to run it.

[JDWhiteWRX]

Looking really good!!

What is the output of that alternator? I can't imagine this car needing all that much current to to run it.

 

 

Thanks mate, its just a 60 amp. I will have electric water pump and electric power steering but that's it really, no headlights, abs, sound system, electric windows etc.

[RX25SE]

I would think 60A is more than enough, even with electric steer.
I assume you will run a small battery for weight saving? I suppose worst case is the battery discharges a little when on track so you have to charge it in the pits.

[JDWhiteWRX]

Reasonably small lithium motorsport battery.

[El_Freddo]

Ooh shiny!!!

Looks good Joel! What colour will the engine be painted in the end?

Cheers

Bennie

[JDWhiteWRX]

I don't have any plans to paint the engine, maybe just the valve cover but I'm liking the red so far.

[JDWhiteWRX]

My new wheels should be here within a week or so and to make sure I can get them straight on the car I had to fix a problem first.

 

The front Mazda RX8 hubs I'm using have a different size thread than the BRZ hubs on the rear. Luckily the RX8 wheel studs are smaller so I can drill them out and press in some BRZ wheel studs.

 

BRZ left, RX8 right.

 

 

To do this properly the The drilled hole should be 0.20 - 0.25mm smaller than the knurl diameter of the wheel stud being pressed in. A 14.0mm drill made my hole 0.35mm smaller but considering the holes will be drilled in a press and not using the precision of a mill this was acceptable as the hole would end up slightly larger using the drill press as some movement will occur.

 

Holes drilled

 

 

BRZ studs in the freshly drilled holes, I started them in the vice and then took it over to my 12 tonne hydraulic press.

 

 

and done.

 

 

So now I don't have to worry about using different size wheel nuts at each end of the car. Ultimately I will buy new front RX8 hubs and press in some ARP wheel studs, this was just a proof of concept and allows me to put some wheels on and start the body work required to make them fit. The car is at least 80mm lower than stock so there is lots more cutting to do around the wheel arches.

[allpaw4]

Nice work! Was going to say that the thread pitch looks different between the two studs. Is the Mazda a 12x1.5 and the suby a 12x1.25? Always wondered why manufacturers do things differently is this regard...

Cheers,
Ben

[RX25SE]

Nice one!

[JDWhiteWRX]

Different thread pitch for sure, all I know is I have some nice wheel nuts that I want to use leftover from my wrx and they didn't fit on the front hubs. I could just buy some nuts to suit the front but the chance of mixing them up and stripping threads concerned me.

[allpaw4]

Yea, I'd be sceptical about using different nuts between front and rear, you'd mix them up for sure.

[RX25SE]

Reminds me of the old Valiants.  LH thread wheel nuts on one side, RH thread on the other. 

 

 

 

It was fun to swap them over when an apprentice had the wheels off when doing a service!