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View Full Version : Chassis modifications before powder coating



gpaterson
12-23-2015, 11:13 PM
I thought I would take the time to share with other builders the slight modifications I did to the chassis of my 818. There is nothing particularly original here, I more or less gathered all what I thought were the good ideas from others in the forum and put them into my car. I am sure there have been quite a few improvements and innovations from when I did my chassis about 15 months ago. There is probably nothing I wouldn't do again either.

So here is the list.

1. Locate the fuel tank in front of the car rather than behind the seat. This had a few knock-on adjustments like having to change the gear-shifter so the cables faced rearward so changed it for an MR2 shifter (an easy change). It also was cheap, shortened the cables making it a better feel. To maximise the size of the tank for using on the track part of the front chassis was modified so the tank can be removed. The tank placement provides better weight distribution. It was custom made but an off the shelf tank is probably able to be purchased in larger markets than New Zealand. I used all the Subaru bits including fuel pump and gauge.

You will read comments that the cabin is ok for people 6' (183cms) and taller but don't believe a word of it. I am 182cms and feel the single biggest compromise the designers made is on leg room. I have largely engineered around it but I will say it is a compromise between pedal position, seat incline and keeping the top of your helmet below the roll bar.

2. Locate the intercooler at the rear of the car. Granted the coupe has better intercooler air flow but I felt that the S was significantly compromised by its air flow into the engine bay and through the intercooler. I also think that heat soak off the engine is a WRX issue so took the opportunity to engineer around it and the pipework wasn't complex. The intercooler frame serves to mount the wing (purchased in NZ). The intercooler has twin 10" fans to provide cooling when the intake temperature increases e.g. when stopped - a cheap unit for Jaycar. I use the windscreen washer tank to put water onto the intercooler.

3. I always intended to have a hardtop as it rains in New Zealand so fitted an air conditioning unit. I used the Subaru components and a cheap evaporator ex China. Job done. Lots of other minor interior modes to keep in simplistic at dash level and fully featured in the console.

4. To avoid the look of a kit car interior I have used the WRX centre console. Worked well with the other shifter mods and everything that goes from front to back goes through the tunnel except cooling pipes. I will use an Android tablet for supplementary gauges, track timing, music and everything else I need mounted into the WRX console. Not yet done but seems to fit very nicely.

5. Made up a custom set of cooling pipe elbows. Makes it easier to bleed (not easy but easier!). Need only to have the pipe mounts figured out at this stage.

6. Had to start from scratch with the pedal box. What a dogs breakfast - maybe the internet doesn't work in the USA as buggered if I know how they thought the right hand drive pedal box was ever going to fit. I think FFR have changed it since.

7. A proper harness bar. Has created a headache or two for doing the body work but it is at the recommended angle for the race seats I am using.

8. When I got my kit there was no windscreen wiper factory mod so I fitted a Benz W203 single wiper. Wasn't easy and probably would look for something better if I was to do it again. It has created a few issues with bonnet fitment but certainly looks better than the factory attempt. My advice is to do it yourself if you are up to it.

9. Numerous tabs and mountings like some tabs to mount a bash plate under the engine that can be removed to change the oil. Numerous small changes to the mounting of engine accessories, wiring and fuse boxes.

10. For New Zealand compliance you will need to weld in the seat belt mounts. Justin at the LVVTA has the design from Junty's car and mine are different from his but ok also. You will also need to weld a decent gusset on the top seat belt mount as the standard FFR mount will not pass NZ compliance. Ignore that if you only intend to use a harness - mine car has both.

After all that was done then I got my chassis powder coated locally. Cost about NZ$600 (about US$400).

If any one wants photos of the mods or more information I am happy to continue this thread. Conversely if I have bored you to tears, thanks for indulging me.

Merry Christmas people.

Kind regards
George

Flamshackle
12-24-2015, 03:44 AM
i thought i would take the time to share with other builders the slight modifications i did to the chassis of my 818. There is nothing particularly original here, i more or less gathered all what i thought were the good ideas from others in the forum and put them into my car. I am sure there have been quite a few improvements and innovations from when i did my chassis about 15 months ago. There is probably nothing i wouldn't do again either.

So here is the list.

1. Locate the fuel tank in front of the car rather than behind the seat. This had a few knock-on adjustments like having to change the gear-shifter so the cables faced rearward so changed it for an mr2 shifter (an easy change). It also was cheap, shortened the cables making it a better feel. To maximise the size of the tank for using on the track part of the front chassis was modified so the tank can be removed. The tank placement provides better weight distribution. It was custom made but an off the shelf tank is probably able to be purchased in larger markets than new zealand. I used all the subaru bits including fuel pump and gauge.

You will read comments that the cabin is ok for people 6' (183cms) and taller but don't believe a word of it. I am 182cms and feel the single biggest compromise the designers made is on leg room. I have largely engineered around it but i will say it is a compromise between pedal position, seat incline and keeping the top of your helmet below the roll bar.

2. Locate the intercooler at the rear of the car. Granted the coupe has better intercooler air flow but i felt that the s was significantly compromised by its air flow into the engine bay and through the intercooler. I also think that heat soak off the engine is a wrx issue so took the opportunity to engineer around it and the pipework wasn't complex. The intercooler frame serves to mount the wing (purchased in nz). The intercooler has twin 10" fans to provide cooling when the intake temperature increases e.g. When stopped - a cheap unit for jaycar. I use the windscreen washer tank to put water onto the intercooler.

3. I always intended to have a hardtop as it rains in new zealand so fitted an air conditioning unit. I used the subaru components and a cheap evaporator ex china. Job done. Lots of other minor interior modes to keep in simplistic at dash level and fully featured in the console.

4. To avoid the look of a kit car interior i have used the wrx centre console. Worked well with the other shifter mods and everything that goes from front to back goes through the tunnel except cooling pipes. I will use an android tablet for supplementary gauges, track timing, music and everything else i need mounted into the wrx console. Not yet done but seems to fit very nicely.

5. Made up a custom set of cooling pipe elbows. Makes it easier to bleed (not easy but easier!). Need only to have the pipe mounts figured out at this stage.

6. Had to start from scratch with the pedal box. What a dogs breakfast - maybe the internet doesn't work in the usa as buggered if i know how they thought the right hand drive pedal box was ever going to fit. I think ffr have changed it since.

7. A proper harness bar. Has created a headache or two for doing the body work but it is at the recommended angle for the race seats i am using.

8. When i got my kit there was no windscreen wiper factory mod so i fitted a benz w203 single wiper. Wasn't easy and probably would look for something better if i was to do it again. It has created a few issues with bonnet fitment but certainly looks better than the factory attempt. My advice is to do it yourself if you are up to it.

9. Numerous tabs and mountings like some tabs to mount a bash plate under the engine that can be removed to change the oil. Numerous small changes to the mounting of engine accessories, wiring and fuse boxes.

10. For new zealand compliance you will need to weld in the seat belt mounts. Justin at the lvvta has the design from junty's car and mine are different from his but ok also. You will also need to weld a decent gusset on the top seat belt mount as the standard ffr mount will not pass nz compliance. Ignore that if you only intend to use a harness - mine car has both.

After all that was done then i got my chassis powder coated locally. Cost about nz$600 (about us$400).

If any one wants photos of the mods or more information i am happy to continue this thread. Conversely if i have bored you to tears, thanks for indulging me.

Merry christmas people.

Kind regards
george

pics pics pics more more more ;)

Bob_n_Cincy
12-24-2015, 10:36 AM
George,
I read every line twice.
You had to tackle a lot of the Wookie designs that I did.
Great to see others pictures, to see if our thought processes are the same. Post away.
I also would not change much if I did it all over. I've already done each task 2 or 3 times on the first car until I was happy.
I do get a chance to do it all over again. First car was Michael's, next one is mine. Starting soon.

Merry Christmas
Han Solo & Chewbacca

gpaterson
12-30-2015, 10:27 PM
Tank location modifications

The tank in #220 was relocated forward to in front of the front bulkhead. This was done mainly to allow more room in the cabin. The second benefit was to provide better weight distribution i.e. moving some weight forward. The goal was to maximise the fuel tank size for track work. It holds about 50 litres I think without space for the brake booster. The work was undertaken by Macbilt in Grenada North.

The bracing is removed forward of the front bulkhead. We drilled 4 holes so that the removable brace can be bolted into the chassis

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That left a sizable gap in the chassis to fit the tank from underneath.

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The removable bracing is bolted back in place when the tank is raised into position.

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As the tank was custom made for the car and uses the WRX fuel pump and gauge. The tank as a bottom fuel pick-up compartment to avoid fuel surge and is filled with baffle foam. The fuel filler is on the front left guard (NZ cars tend to get fuelled on the left side).

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The created a need to run the shifter cables backwards rather than out through the front bulkhead and around. The tunnel was modified and a modified MR2 shifter used (Via Trademe for $45) - I had always intended using the WRX centre console to make it look less like a kitcar with the squared-off tunnel so some mounting points were added at the same time. The shifter cables were also shortened with a more direct route to the shift linkages.

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And with the ABS unit fitted and twin bias valves in place. I am sorry it looks a bit of a mess but works quite well.

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I am yet to fit a mechanical reverse block-off which is easy to do with this shifter too.

To get a better perspective in early go-kart form.

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That's about it.

I would recommend this modification if you are my height 182cms or taller. I still feel space is a little compromised but nothing that I can't live with.

Happy New Year people!!
Cheers George

Kurk818
12-30-2015, 11:15 PM
Links dont work

Bob_n_Cincy
12-31-2015, 01:20 AM
Excellent job George,
Keep up the good work.
I still have to make the structure for under my tank.
What rules do you have concerning reverse lockout?
Did you know that the transmission has a device in it that does not let you go from fifth to reverse?.

Bob

Flamshackle
12-31-2015, 04:10 PM
Great info George! Thanks for taking the time and effort to post it up here...

Have you got any pics of the finished fuel tank installed? Also where did you get your shirter shifter cables from in NZ?