zep's Gemini Coupe

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I finally got around to fitting the rear wheels to assess how much room I have in the wheel wells and see how much I need to shorten them by. Turns out I have hit a snag that might turn into a blow out of a range of proportions.

Here's where I'm at with the fitment:

Looks like I have about ~33mm to try get in the arches. Looking from the other side, there is about 50mm between the tire and the chassis rail, so I figured that's not too bad. However, there is a decent amount of meat where the inner and outer guard skins meet, so I'm really working with only about 10mm of extra space in there. From the outer fitment point of view, I will definitely have to pull out the guards some -the plan is to keep them looking as stock as possible. I thought I could remove the inner skin where it meets the outer and weld it back in higher - not sure if this is a legit thing to do or not? Do I need double skin all the way down?

The other issues is this:

I only have about 7mm of spline I can cut off. And because the axle tapers in, I can't put the splines in the exact place I need them to be if I were to cut new ones. I've spoken to a bunch of diff places and none recommend filling and cutting new ones, so I figure I have 3 options.

1. Find some longer 5 stud axles that I can cut off after the taper and respline. I've looked around and turns out 5 stud ones (with the right centre bore diameter for my wheels) are pretty hard to find. Most seem to be 6 stud.

2. Get some billet axles. There are PLENTY of places that will make axles to a custom length in 30 spline and whatever stud pattern you want. The main problem is that none of them make an axle with the hillux bearing size. I could go down this route and try to find a bearing that will match the housing on the outer and whatever axle I choose on the inner. I did a quick check on ford 9" and couldn't find any in the right specs. I need to look a bit harder and longer as there are heaps of different axle diametres out there.

3. Convert to full floating. Today I spoke with a guy who makes full floater kits. You cut off the housing flange and weld on the one he give you, buy his axles which will be made to fit, and bob's your uncle. This is considerably more expensive than just buying axles and from what I've read, the only real benefit comes from if you ever snap and axle, which I feel like I'm unlikely to do.

Any thoughts on this?

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I have since has a chat with a man who knows everything about Hilux rear ends and have been assured that I can use any axles from any Hilux or Hiace. Now I just need to find the widest one possible!

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Wow! I really haven't updated this in a while. There's been a bit of progress in the last 7 months, but not a heck of a lot. I've been mucking around with brakes, dashes, diffs and cooling.

In the end, I decided that shortening my axles the "build up and machine down" way was going to be okay, so I sent them to Howat Engineering and had 35mm lopped off and the splines cut back on.

I then took the housing to Tin Tricks where it had the Gemini mounts cut off, was shortened and had the 4-link brackets slid on.

I left the ladder bar mounts on so it still had a way to mount to the car when I had to move it. Turns out I was spot on with my measurements. The wheels just sit inside the arches - will need some work done to get unobstructed bump - and I have about 15-20mm clearance on the inside. So pretty happy.

I've also spent a bunch of time prototyping up some parts with the 3D printer.

Throttle body adapter:

Brake caliper adapter:

Master cylinder adapter:

And for those of you who recall ages ago I was trying to make a new tacho face for my dash, I've gone in too deep. I've designed and printed up an adapter which uses all the stock mounting points and screws, as well as a new face which has the cutout for my CAN screen:

I then had it MJF printed in PA20 nylon. Unfortunately it warped so I need to have another go and add some ribs in to strengthen it.

I was planning to paint it myself using modelling paints, but I'm not sure that I have the ability. I spoke with Charlie's Pinstriping out west who said they could do it. When I get around to fixing up and printing a new version I'll take it up.

Last thing that I've been doing for quite a while is working with Ross Performance in Australia to develop a harmonic damper and water pulley for the Isuzu 4Z engines. They have pretty much finished, I'm just waiting on one or two people to test some 3D printed templates to make sure everything lines up.

And lastly I have been talking with Skeleton Welding down south to build me a new radiator. It's been a bit of a packaging saga to try and fit the radiator, intercooler and oil cooler up front. But I think with a bit of ingenuity I'll be able to make it work. Speaking of the oil cooler, I got this "cool" one from CSF:

The car is now in at Shores NZ having the 4-link boxes welded in and the rear turrets strengthened for coilovers. So progress is happening!

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Things taking a little longer than I had hoped, but yesterday I got some good news. The 4-link boxes are in and I'll go and have look on Friday and figure out what the next steps are.

I also heard from Skeleton Welding that my core has arrived, so should be getting that sorted to soon too! Pretty happy with the progress.

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Almost done with the 4-linking. Tim has opened up the tunnel so nothing can hit at full bump, and closed up the channel that was cut for the old ladder bar.

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The car is back home now. The brackets and tunnel are done. Next bit to do is buy some coilovers for the rear and mount them up nice and neat. I've decided to swap the upper rear mounts from single stud to and eye, for ease of buying the coilovers as well as strength.

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It's been a while since I've updated. Not a heap of progress. I'm at a place where I need the rear shocks (at the very least) so I can finish up the diff and coilover conversion. At the same time I'll sort the front gussets and then we should be ready for paint.

Otherwise, here's a few pics of what I've been up to since my last post:

The fender mirrors I got from Malaysia were in pretty good knick apart from the plastic mounting plates. I spent a bit of time mucking around with Fusion and managed to print out a pretty decent replica. I'll probably get them printed in nylon when I actually put it all together. Also had the hardware chromed so it should last a while - not beautiful but you don't see it and it should do the job.

I picked up a MUA-5 Rodeo gearbox which is larger and stronger and allows me to switch to a hydro clutch. Bolts on and works with my existing flywheel. The remote shifter is super gross but unfortunately the gemini one, while I could easily mod the bolt pattern, is about 5mm too short. It shifts but I'm not into it. I'll figure something out.

Bought an old barry's parts collection for no real good reason other than to have some spare parts. Anyone want a set of 4x100 Rostyles?

Took a mate's gem out to be corner weighed at Road Race and Rally. Needed this figures for the getting the shocks made, which I'm waiting for from Shockworks over in Aussie.

Been mucking around with printing new demister funnels since every stock one in the world has snapped at the bolt holes.

Also had a go drawing up headlight surround clips. These will definitely need to be printed in something stronger too.

@Jerm CNC'd up the Bosch DBW throttle body adapter that I designed. Super happy with how it came out.

Got some new SSR centre caps made up in Japan. These are the MKII style, but I like the picture better than the MKIII one.

I drew up and had laser cut a new dash panel for all the different switches I need, including the bluetooth stereo. Took ages to find a font that was similar to the original!

Unfortunately I had to ditch the Brembos as I could just not make them fit with the SSRs. I even bought shorter bolts and they still hit them with the deepest offset disc I could run. So I swapped for Wilwoods and bought some new Znoelli rotors for front and rear. Front ended up being s13 Silvia 4 stud rotors. I drew up and printed a new caliper mount, the one in the pic is not quite right. Thanks to @slacker.camfor helping me do the hard measurements yesterday and for helping me redrill the rotors to suit the Gemini hub. I've drawn up a new one that should be perfect.

I also finally welded up the Wilwood brake master cylinder mount. Pretty happy with how it came out. I have also decided to run the plastic reservoirs as it's just waaaay easier.

That's about it!

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This week, two long term parts of the projects have arrived, like a fine wine plucked from the cellar. The first is a pulley set from Ross Performance Parts over the ditch. Isuzu 4Z engines are old but are having a revival among enthusiasts striving for good reliable power. For most of us, this means we have to develop new parts. While I'm waiting on others to develop parts for the top end - a new cam, high ratio rockers, etc - a few days ago I finally got my greasy mitts on this harmonic damper and waterpump pulley that I commissioned Ross to develop over a year ago. We got a group buy together and made it happen, and I am beyond stoked with how it turned out, but let's let a picture do the talking:

Look at them! The majesty! The next part started off as a simple request for a nice crossflow radiator and spiralled a touch. A huge thanks to Skeleton Welding down in the depths of the Mainland for putting together this intercooler / oil cooler combo for me. Well, he made the intercooler and modified a CSF oil cooler to fit nice and neatly. They turned up this afternoon and... wow! Such craftmanship! A perfect fit with zero ability to see the car in person. I opted for no in/outlet piping so I can get it all lined up at a later date, but it is looking great. Now that I have this, I can measure where the radiator needs to be mounted, and using the Ross pulleys I can figure out where the fan and (hopefully) shroud need to be positioned. This pictures, you ask? Just look!:

A last update follows on from the post above. You'll have seen the new dash switch plate I made, trying to look as retromod/periodmod as I could. Well I finally had a go at trying to get the stereo switches to work. Now that I've finally got a 12V  signal on the work bench I could finally have a go. Here's a video proving it works!

Stoked with this too. Just need to wire in the volume pot to the panel and that's half of it done.

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Shit I'm lazy at updating this thing. Just gonna trawl my gallery and make a few posts.

Aaaaaages ago I posted about trawling Pick-A-Part to find a decent pedal for my e-throttle setup. If you recall, this is what I ended up with - it's from an Outback (stock Gemini pedal on the right):

I was always keen to keep it looking stock, so I built a jig that is very gross but worked well, cut the Gemini pedal off and, after a lot of bending - including the use of a forge to heat up the arm - welded the pedal on. No one will ever be able to tell!

FORGE POWAH!!!

All done! Need to clean up some welds and have it powder coated still.

Let's see if it fits!

So yeah, there's only one bolt that actaully goes in from the stock setup. But that's all good, I'm going to build a new mounting platform for it anyway so I can shim it in and out and fine tune the pedal offset between it and the brake pedal.

 

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Last one for tonight. I bought some new seats. Cobra Nogaro. They are super nice, have inflatable lumbar support and low hips for using regular lap belts.

I am also waiting on some of this Porsche multicolour fabric to retim the cushions.

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Next up are the rear brakes. Not a whole lot to say about these. They're the same AE101 Levin brakes that I used on my Hilux diff before. Pulled them apart, had the external bits gold passivated and the bodies coated by HPC. Bought a kit and put them all back together. I've also got some new Znoelli rotors to complete the rebuild.

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Last bit of the recent puzzle is the suspension, which started probably a year ago. I always had custom springs and a nice uprated Whiteline swaybay up front, but never really got around to doing anything with the dampers. Now that I've gone 4 link, I decided to coilover  the rear and find some suitably good front shocks to match. I spent countless nights measuring and making spreadsheets. I looked into rear coilovers from T3, Fortune Auto and others, and fronts from GAZ, Bilstein, Koni, Avo, Spax, etc. Nothing really seemed to be exactly as I wanted it. So I figured fuck it and decided to go custom. Looking around, I first called MCA but I didn't get the feeling that they would really put in the effort I needed for my setup. Then, while asking @Truenotch what he'd done for his race car, he mentioned Shockworks over in Aussie. I gave them a call and got a real good vibe from them. They were stoked on my project and keen to help, so I got together all the details they needed, including the corner weights of a stock Gemini as seen a few posts above and waited. And waited. And waited. And waited...

I'm still waiting. But now I'm in Melbourne waiting for the Grand Prix to start. So I figure I'm close enough to go out to their shop and give them a kick up the bum. I coax my sister into borrowing a friend's car and driving me out into the Dandenong ranges which is where they are located. I'm glad I did this, because it really lit the fire and not long later, here we are:

Looking damn fine. And now I can finally set off the next season of my Rube Goldberg machine which should see the car back in with Tim at ShoresNZ to finish the diff and coilover conversion and then hopefully off to the paint shop!

The last new bit for the suspension is a Whiteline swaybar for the rear. The car never came with a rear bar so this should be a good upgrade. I borrowed an AE86 one from @slacker.cam to mock it up and it fit good, so I bought one:

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Ooooookay. So the next milestone is done: 4-linking and rear coilovers sorted and some strengthening up front.

Continuing on from my post last August (!!! what?!), now that I have got the suspension parts from ShockWorks, I took the car back to Tim at ShoresNZ to finish off the 4-linking and coilover conversion. It started off with cutting out the old rear turrets and building some butty new ones that are able to hold the weight of the car. Tim builds these as a bolt in mount:

The rest of the rear end included welding up all the link mounts, building new ones for the shocks, swaybar and panhard rod. Tim also made a new panhard to suit the new setup.

I also had Tim build some gussetting around the chassis to firewall interface, as having the side intrusion bars as part of the half cage tends to stiffen the rear up to the bottom of the A-pillar and leave it all flexy up the front. Ideally you'd just have a full cage but I don't really want to do that. So this should hopefully add some strength and stiffening to the front of the car.

Next thing is to get the rear end properly rebuilt and coated. And obviously continue with the other million things I'm working on!

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I'm after some OS hivemind thoughts on two things:

First -  tires. When I had my wheels widened, I went with 7.5 and 8.5. I figured that as 205/50s and 225/45s have very similar sidewalls and the width is not much different (approx 5mm), they should look similar on the wheels. Now most people would probably not pick it, but the I can't stop seeing that the rears are more stretched than the fronts. These are Nankang AR-1s.

I'm not sure if I should just get over it, or try and find some tires that will have a more similar look front and rear... while also being able to deal with a good amount of power. Any thoughts?

Second - where to put my battery. I'm planning to use a FullRiver HC20 and have mocked up a box. I don't really want to put it all the way in the boot, so I've got three ideas.

Under the rear seat delete panels:

(Mostly) under the centre console - it probably covers about 2/3 of it:

Or under the passenger side dash, which will also house the ECU/PMU etc:

As long as it's well fixed down, I'm not sure there are issues with any... maybe under the dash is too close to the passenger in the event of a crash? Running the big-ass cables to the rear seat is kinda annoying, and having it sticking out from under the console might look a bit naff. Thoughts? >>>

 

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What's been happening as of late....? I'm still working on the dash cluster and will hopefully have an update on that in a week or so. Otherwise I've made a change to my fully sick ICE setup. I borrowed an idea from that dude on Instagram "3Dmagicmike" and bought a Fusion marine head unit. It fit pretty nicely into the center console:

It just needed something to make it look a bit more integrated. So after some prototyping I came up with some side covers that also act as mounting brackets:

I'll probably get it printed professionally so it holds up to temps, but I'm pretty happy with it.

I also had a Gemini mate over the ditch make me up one of his exhaust manifolds (p.s. he may or may not have done some work for the MCM boys, but I guess that's for a future episode.

Here's what it looks like on my dirty old engine:

And we did a bit of a mock-up in the engine bay:

This was also to see if the sump clears, which is finally finished. I'm pretty happy with it. It is now no longer lower than the crossmember and has enough room to get a dump pipe under the car. I designed it with some rubber trapdoors so hopefully it works as it's my first try doing this!

I also had my seat cushions retrimmed with the Porsche fabric. Now I just need to figure out how to integrate it into the door cards.

I've also been back to figuring out my front brake brackets and have significantly simplified them.

And that's about it. Other than adding more things to the collection: ARP head bolds, MaxSpeeding rods. Oh, and I mounted the clutch master cylinder though I don't have any photos of that yet.

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So it seems that time flies and not much gets done. It must be time for my biannual update. Where to start...

After at least 5 years of changing my mind on how to achieve it, I've finally finished my "restomod" dash.

I've swapped the locations of the tacho and speedo, made a new tacho face from stratch that mimics the factory option but has a GaugeArt CANBUS panel gauge in there. I've also changed all the coloured warning lights to white symbols on black with the appropriately coloured led behind them. E.g.:

The rear is looking a bit more complex:

Also finished the dash switch panel. I didn't take enough pics of all the development to make this work but I'm pretty stoked with how it turned out.

I also finalised my front brake caliper adapters and had them machined:

Seem to fit nicely:

'

Next thing to do is finish the WSS sensor bracket and pickup ring. My 3d printer is out of action at the moment so I'm a bit delayed there.

I got Kelford to regrind my cam in lieu of the bigboy billet cam that is still seemingly in hiatus in Aussie land:

Bought a clutch:

Lastly I've been working on a new heater system. Need to have the vents properly printed in carbon-nylon or ASA or something, and have the heater core mounting plate cut and folded.

Other things that happened:

- I had to redo the axles as I wanted to have the discs on the outside of the flange, rather than the inside. So with some help from @alfalfa on the tools at the New Plymouth pick a part to get me some Surf axles and Brian at Howatt Engineering, I've now got new, way nicer axles, ready to be reinstalled.

- I've stipped a bunch of suspension components which are currently at the powder coater, including the axle bearing housing that will mean I can put it all back together soon.

- I'm currently doing the thankless task of removing the underbody sealant so I can have the shell blasted - aiming to get it to the panelshop in June.

- The engine is at the machinist and I'm having some custom 9:1 CR pistons made up by JE. Hopefully getting the head to the right people in the next few weeks for a port and valve upsize

- I bought a hoist which I need to install in my garage. Requires some new concrete but also to be able to move the car, which I can't do right now... watch this space.

That's about it. I've probably missed a lot of things, will update as I remember.

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Got some bits back from the powdercoater. Unfortunately the masked up the front hubs wrong so are going to strip and redo them.

Next stage is to fit the bearings and hubs to the axles and recheck my bump clearances now that I've moved the discs to the outside. I think it should be okay but if not, I don't think there is much more than a light massage in it.