EG Civic / S15 Silvia – Buttoning things up

We’re already up to Part 5 of the Impossible Fabrications / Nulon EG Civic build. In this installment we start at the back of the car to see the rear suspension framework finalised, and an alloy fuel tank fabricated. Then we work our way along the tailshaft and custom transmission tunnel, before heading to the front of the car where the bay is resprayed and the engine re-fitted. It’s almost time for SR20DET  RWD Civic burnouts!

Click here for the Nulon Civic / S15 build index.

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With the front and rear ends now tacked in, we had an idea of how its all going to work, the list of things that we now need to finish to get this car driving under its new power plant is getting bigger now not smaller.

First on that list was to finish the front and rear towers. This means Grub was off to see Neal from Rustride to roll out the rear shock towers so they would look like a factory setup. Rustrite forged a name in the Automotive world for simply being the best in the business and re producing panels that are no longer available or affordable to get, while we where there he was making, Mini door skins, VW Combi split window surrounds, LJ torana boot lids, the list goes on.



Grub made a template to get the shape from the top of the tower, this means less molding work once we shape the towers. It also means we can make the towers at another shop and check they are the correct size before we bring them home.


This just proves the right tools and equipment are key in a build like this.  Once we found the center line of the tower, it only took about 10 minutes to roll them out.


To get the towers matching up with the body, we made wooden templates to match the shape of the Civic. Once we make 2 for each tower it was time to mold and shape the towers in place.


The time consuming part was to hand fit the curved towers, This was made up of trail fitting, hand shaving the high points and re fitting again.


The design that Impossible fabrication created will look factory once painted, The extra time spent on marrying up the towers has really paid off.


One of the desired outcomes of this car was to keep a flat boot. This means the fuel tank has to be under the car somewhere, the problem is we have a diff and a drive shaft in place so there was no real room for a fuel tank, That was until Lyle from Gunna Welding and Fabrication dropped past and came up with a solution. He is going to make us an SLR Torana style drop tank off the rear subframe that will be hidden by the rear bar.


When Lyle came back with this tank we were in shock, his craftsmanship and attention to detail is second to none. We couldn’t of been happier.


Check out the welds. Lyle had this tank, designed, fabed up and welded in less than 1 week.


Because the Civic will be used for lots of different types of Motorsport we needed to make sure the tank would give us a constant flow of fuel. Lyle put 3 baffles in the tank with 100m holes and a 5mm gap along the bottom. On top of this he created a swirl pot (Mini surge tank) in the pick up which means we dont need to run any other tanks in this car to handle 500HP plus.


To meet engineering standards we still kept the tank 200mm from the back (metal) of the car, Grub also put his skills to use by fabricating a rear crash bar with 3 crumple zones built in. We will show you more of this feature once the build is complete. The tank fits like a glove, what we were worried about is that we didn`t have enough room to fit a tank big enough to drive on the street. Guna Welding and fabrication got this tank in the space we gave him and managed a massive 44L which is 15 liters more than we thought possible. Check out his Facebook page for the full build on this and other tanks. He is simply the best in the business.


This was the real test, we wanted to get the tank under the car but not draw too much attention to it. The tank cant be seen from behind the car, unless you are sitting on the ground and looking for it. The car is really coming together, now its time to focus on the front end.


With under a week to go we had to really start pulling our finger out and build this Civic. We had about 5 days to finish the build and about 3 months work of work to do. The front and rear ends were tacked in so the next step was to fabricate a tunnel and firewall, not only was this going to give us the room for our drive shaft and gearbox but it was also going to play a major part in strengthening the chassis, Civics are not meant to be RWD so the chassis needed some love to be able to withstand what we are going to throw at it.


We tacked the tunnel in it was time to bolt everything back in to make sure we had the clearance needed, and nothing touched. Using a custom one piece drive shaft saved us alot of time (and money) we had to extend the current 2 piece shaft by 55mm which doesn’t seem alot but to think that the Civic wheelbase is LONGER than S15 keeps spinning us out.


Some things are meant to be… Would you believe that the 200sx steering rack more or less bolted in. Grub worked his magic on a donor column and we managed to get it to bolt up to the civic body. Tick one more thing of the “to do list”


Next up was the firewall, We needed to make sure that we had enough room on either side, while still maintaining the factory look from the outside. It also meant that we have to relocate our brakes and clutch as they used to run behind the motor.


We cant give away all our secrets, but once we finished the firewall it was time to give the whole engine bay a once over, Joel and Grub worked through the night to get this engine bay sorted, cleaning all the holes up, smoothing it all out, Joel even used the factory sealer along the joins to give it the Factory Honda (ish) look. Not bad for a 3:00am finish.


One engine bay ready to accept the SR20 it was built for. The bay looks great, this is whatr you get when you spend the time and get every last corner of the bay ready before painting. We decided to paint the engine mounts black again as it would match the motor much better. Now for the exciting part. We get to start bolting things on for the final time.


This photo just goes to show you how much work went into the front end of this car, Grub fabricated new chassis rails, filled and strengthened them. This is the finished product. Joel wasted no time, mounting the brake booster, battery, Headlights and wiring, we also started running the engine loom and fuel lines.


Fuse box is in, Those 200scx shock towers look factory, Impossible Fabrication did an incredible job making this car look as neat as possible.


 Brendo got a new haircut and decided he was going to help. Thanks mate, couldn’t of done it without you.


  We run GKtech fans on all our cars and the civic would be no different. 50% more airflow would help greatly as we are running the front mount cooler inside the front reo. it took about 2 minutes to install and looks heaps neater than factory as well.


 New fan fitted, it was time to mount this baby in its final resting place.It was alot easier to keep it all together, but did take 3 guys to line up the suspension, engine mounts and gearbox mount. Lucky at this stage in the build we couldn’t keep people away.


Like a glove..  The engine bay looks amazing with paint and removal of the old mounts… now its time to start bolting it all together and see what happens…

Stay tuned for the next blog, it might involve a civic getting kicked out of an airport for doing burnouts…


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