I've always loved the look of the BNR34 V Spec II rear diffuser, unfortunately they're expensive second hand and even carbon fibre copies are £1k. So i decided to attempt to make my own using inspiration from it. I'm by no means a fabricator so please be easy on me lol
The first decision was material, I wanted the brackets to be strong, the main diffuser strong enough to be sturdy but doesn't weigh a tonne. I decided to use 2mm thick angle iron for the side and rear brackets and 1.5mm steel box section for the front bracket.
Looking at mounting points and there is a part of the chassis that sits lower than the bumper, this should be ideal
The diffuser and fins were going to be made out of 0.9mm sheet steel. I did think Aluminium as its easy to work with but its too soft IMO. I started off with a card board template, unfortunately the exhaust sits too low at an angle for the whole diffuser 'body' to be a single piece. I tried cutting a hole to try and clear it but it left minimal material at the bottom and it would eventually snap.
So i went with a 2 piece design instead
I started off with the passenger side as it was smaller and easier to mount. A slot was cut for the exhaust hanger with enough room for any movement. The rear is braced with a piece of 2mm flat bar which uses a bolt in the wheel arch to the right side of the shock absorber.
The box section bolts through the boot floor, this helped angle the diffuser down rather than having it flat. This was the first prototype for the box section, later on I made it longer so it covered the width.
You may remember me making a rear tow hook awhile back. I decided to incorporate it into the design by cutting a slot, again enough roof to not catch it when fitting/removing.
I seeked help from some friends as I don't have the skills/equipment to weld or fold sheet metal perfectly.
With the fins folded I could mock the ends up. These would be bolted on and use the same mounting points as the diffuser itself
The rear bracket was made and mocked up at the same time. I also marked the holes for the centre fins ready for drilling. At this point I decided to give the front of the diffuser a minor bend upwards rather than leaving it straight.
With everything fitted for one final time,checking clearances and everything was solid and not rattling/vibrating it was time to drop it off for powder coating. Originally I thought about having it done in black, but with the lower black trim just above it, I feared it may get lost and wouldnt be seen. Only other option was silver, the powder coater only had a satin silver so I bit the bullet and went with that.
I ordered stainless nuts, bolts, washers and rivets for the final fit
I've made flat under bumper splitters, canards and other little bits and pieces in the past but this was certainly my biggest challenge. I think its turned out very well
Well that is an art I would like to master,metal fabrication that is.
That does look very good although I would have gone black but that would be my only change but it is easy to be critical from a keyboard. It is a job well done and thank you for uploading the pictures.
On Monday 27th July we welcomed our daughter Mia Rose into the world. Mum did an absolutely amazing job and active labour was just over 3hrs long. She's yet to go out in the R34 yet as we still need to sort out the car seat (isofix in the daily Mazda 6 is a god send)
After damaging the Work Emotions back in February, they were refurbished during the Covid-19 lockdown. From the factory in Japan the inside of the spokes are darker with a very bright outer face. The company were able to replicate it,but unfortunately the outer face is slightly darker. I had all 4 wheels done so they all match and they look just as good as before!
The car is filthy and is in a need of a deep clean but couldnt resist getting some photos
In September I was lucky enough to attend the 2nd show of the year dodging the national lock downs, this was Modified Live Snetterton. Would have been rude not to as the circuit is only a 20min drive away.
On the drive home the car threw up the TCS,SLIP and EML lights on with no change in the drive of the car. I took it to work the following week and I experienced a very bad misfire on the way in.
Not having access to Nissan Consult I did the paperclip trick and code 21 appeared, which points at the coil packs.
I removed the coil packs to check the resistance to find 4 out of 6 had no resistance. I'm guessing they're fine on initial start up but break down when they get hot (driving for 10mins after start up the misfire reappears)
I also noticed 3 out of 6 cylinders had oil down the spark plug chambers and on top where the coil pack sits. So I started to strip it down while I wait for a replacement gasket and half moons to arrive from Conceptua Tuning.
This was the first time working on the engine especially an RB, and wow what a ball ache this was haha
With the gaskets and spark plugs changed it was a waiting game for the OEM coil packs to arrive from Auto Extreme
Refitting is very straight forward so it didn't take too long to put everything back together
With the car reassembled it was time for a test drive. What better way than a 100 mile trip around the Norfolk coast. The car didnt play up at all and ran like a dream. An added bonus Mia had slept for the whole time, winner!
I'm looking forward to the salt free roads so I can enjoy this again
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