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Nice work it looks like it belongs there
 

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Discussion Starter · #142 ·
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Discussion Starter · #143 · (Edited)
A couple of things came in that I ordered.

A 16 psi lever-type radiator cap for my coolant surge tank I built previously.

And in keeping with the low buck nature of the turbo engine build, I got a stock-type plastic VW/Audi turbo bypass valve for about $16. On my previous Opel GT turbo kit build, I used a VW/Audi billet aluminum aftermarket bypass valve that was about $100. But this engine has a $250 turbo, so no way was I spending that kind of money on a BOV/bypass valve.

Today I ordered an old school analog stopwatch from eBay, which will be mounted to the dash of my Sportwagon for a retro-inspired rally look. It’s a German-made Hanhart stopwatch, which was honestly not my first choice. I really wanted an old Heuer stopwatch, but most of those in running condition were $200-$500. Ouch.

The Hanhart stopwatch only cost me $43, delivered.


I’ve also decided to add an aftermarket heater under the back seat. I made a cardboard mock-up of the heater box to check for clearances.

I was originally going to put a 750 watt power inverter near the battery, but I found a better place was under the hinged access panel I created between the rear shock towers.

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Discussion Starter · #144 ·
I finally took a few moments to check the appearance of my slimmed-down rear bumper. It certainly looks less bulky. I think once it’s fully welded, sanded and painted it will look pretty good.

Here is the ‘before’ and the removal of the original bumper
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Discussion Starter · #145 ·
And here is the ‘after’.
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Discussion Starter · #146 ·
Here’s the battery box I built looking from the underside. You can see that is still quite a bit higher than most of the undercarriage. If this were a road-race car, the battery could probably have been lowered an additional 3-4 inches safely!

You’ll note that this car, being a 1975, has the fairly rare aluminum torque tube. I’ll be replacing the aluminum torque tube with an earlier steel torque tube.

If you are asking ‘why?’, the reason is two-fold. First of all, the ID of the aluminum tubes is smaller. In fact, the torque tube inner shaft can’t be removed without taking the front yoke off first. So in order for me to fit a sleeved inner torque tube (to handle higher HP), I have to use a steel outer tube. Secondly, the aluminum outer tubes are just plain weaker. Fine for modest HP, and they are 1/2 the weight of steel. But not suitable for really hard use and power.
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Next I chopped off the custom 2” exhaust that was on the car. It was pretty nicely executed to be honest, tucked up very tight to the body. The only place that wasn’t well done was the over-axle tube. It had clearly been hitting (and bending) the panhard bar.
I chopped it into 4 pieces, and the amount of carbon that came out of the system was off the charts! I’m guessing that this car had been very poorly tuned and was running pig-rich for years.
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While I was under the car I also scraped the oil that was on the center diff housing. It was more the consistency of pine tar to be honest! Mixed with dirt. Nasty stuff.

More PO nuances were discovered, like the fuel pump wiring. It had a Facet interrupter pump fitted where an EFI pump once was. The power feed wire was extended, wrapped over the brake line on the differential, finally attaching to the pump. And the ground wire…the ground wire was just twisted onto the base of the pump, the other end twisted to a screw on the chassis. Jeez…..

No wonder I have trust issues.
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geez that crap coming out of the exhaust looked like the end of a fire pit LOL
I still can't get over the spare tire fitting in there so well
 
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Discussion Starter · #148 ·
I finally completed my new rollcage main hoop template. It’s made from 3/4” poplar so it’s a bit sturdier than the cardboard or 1/4” plywood that I used to use.

I will be narrowing the base of the main hoop where the tubes land on the pedestals. I need a little more clearance for the side interior panels to clear.
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Discussion Starter · #151 ·
I just tinkered a little bit on the Sportwagon today, some other jobs took priority.

Using masking tape, I’ve pretty much figured how I will route the rollcage door bars, and the overhead gussets.

Typically I would use a ‘taco’ gusset at those corner junctions, but I get the feeling that welding access to the top of the gussets will be minimal even with my removeable baseplates. I decided I will use tubing gussets instead, which are still legal for hillclimbs. Access to weld the tubing is much better.

In addition, I will use tubular gussets to attach the rollcage main hoop to the b-pillar of my Sportwagon. They will bolt to the original upper seat belt mounts.

I then cut out base plate reinforcements for the main hoop from 14 gauge mild steel.
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Discussion Starter · #152 ·
While searching for parts in my shop basement, I re-discovered a cylinder head I had which was pretty much fully machined many years ago for a stillborn project, but along with all my Opel parts it spent 6 years in a damp barn. Unfortunately this cylinder head, though bagged up, got wet when part of my barn flooded. The bag had a tear in it, and it filled partially with water, rusting the bottom end of it pretty well.

The more I thought about it, the more I liked the idea of utilizing it for my turbo EFI 1.9 engine.

First of all, it is my preferred 1971 1.9 10-bolt 4-bearing head.

It had already been magnafluxed, 5/16” bronze guides installed, spring seats machined, and hardened intake and exhaust seats fitted. It had been machined .075” (flat ) to reduce the chamber volume from 54.2 to 43.8 cc’s. I had already started to do some porting work too.

Naturally it needs to be cleaned up and de-rusted. The deck was slightly scratched and irregular from the rust, so it will need about .005” to .007” of additional milling to correct it.

My thoughts are to re-cut the seats for larger valves. Previously I set it up with some custom undercut-stem 1.625” intake and 1.38” exhaust valves, but the hardened seats can support more. I’m thinking custom 5/16” stem valves - 1.75” intake and 1.45” exhaust.

My calculations indicate that if I use the factory low compression dished pistons, machine the block to get them above deck about .005”, and use this small chamber head, I’ll end up with around 8.5:1 true compression. This is in fact a little bit higher compression than factory flat-tops with stock combustion chambers, BUT, a mirrored/dished piston and small combustion chamber is far more efficient at resisting detonation than larger chambers and flat tops.

In conjunction with a boost-retard ignition system, I think I can maintain very good off-boost throttle response while avoiding damaging detonation. Naturally, the combustion chambers will be fully deburred and polished, and the pistons will be deburred and probably ceramic coated too.
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Discussion Starter · #153 ·
Back on the wagon a little today. Yesterday I got a couple of eBay items delivered.

First was my new extendable antenna. This car came with one on the a-pillar but it was pretty much FUBAR’d. Rather than weld up the holes in the a-pillar and redrill the RF fender, I searched out for an extendable pillar-mount antenna so I could use the existing mounting holes. For $22 it should do the trick. I would have preferred to mount the mast towards the side of the car, but it would interfere with the door frame.
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Secondly, the mechanical stopwatch came in. It works great, looks period correct, and the two holes on the lower flange will provide a good bolt-on mounting point to the dashboard.

Watch Hand Analog watch Clock Watch accessory




I ended up cutting off the welds on the hinge pivots for the rear seat base, since I won’t be using the lower rear seat at all. I was doing great until I twisted one bracket too much while there was still sufficient weld bead left to tear a hole in the floor. Oops. Guess I’ll need to patch that up.
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Discussion Starter · #154 ·
I hole -sawed a couple of 1.25” holes in the rear frame extensions, and picked out all the mouse nesting material that was there, followed by a good vacuuming with the shop vac. Surprisingly poop-free.

An added bonus is I now have better access to remove the clips for the bumper mounts.
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Discussion Starter · #155 · (Edited)
Front bumper removed.

There’s some trickery going on that I will have to correct. This car had some sort of front end damage that was fixed years ago. The front clip was from another car as was the left front fender. I see no wheelwell or frame damage however.

One thing odd is they swapped a lower valance from a 1974-1975 with the cutouts for the big bumper rams, BUT there was another valance for the bumper ram tubes that had tow hooks. The holes in the proper valance are therefore not round, but instead teardrop shaped. This car has round holes in the valance and tow hooks, so the valance is actually pressed up against the tow hooks, slightly bowing the sheetmetal.

I’ll have to cut out the valance holes to the teardrop shape and straighten out the sheetmetal a bit.

I also MIGHT remove all the front end sheetmetal, bead blast it, and re-install it. It’s just off enough at the seams that it bothers me. This way I could remove the peeling paint/primer that wasn’t prepped correctly, get everything aligned correctly, and preemptively nip any rust in the bud. We’ll see. I still want to put this body shell up on a rotisserie and that would be easy to do at that time.

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Discussion Starter · #157 ·
Cool antenna! It's all starting to look pretty cool!

😀
Narrowed bumpers
Recessed battery
TIG welded rollcage
Turbo EFI engine
Getrag 240 gearbox
3.90 LSD rear axle
Watts linkage
Wilwoods and vented front rotors
Quaife fast ratio rack
600 watts of auxiliary lighting



All Gordo sees is, ‘Cool antenna’

You truly are Herr wacka-doodle. Lol.
 

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Discussion Starter · #159 ·
I took a trip down to CT today to the powdercoater. He had my wheels ready a few weeks back but I wanted to tie in my trip with some other chores in the area.

So, I got my 13” x 5.5” 1975 rims done in bright gloss white powder. I’m still on the fence when it comes to leaving them all white like a rallycar would have, or painting the inset areas satin black like a stock rim. I’ll probably mount the tires and put them on the car first to get a feel for the look, and decide later.
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I dropped off the steering wheel spacer and a stock EFI fuel pump bracket to get coated in the satin black textured powder.

I brought a stock steel torque tube down, not to get coated, but to sandblast the ends so I can cleanly TIG weld to the metal. I have some reinforcements to make.
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I also brought the Weber 38DGMS carburetor with me. I forgot the accelerator pump covers (doh!), but I wanted to get the carb cleaned up as it was pretty filthy and corroded. I prewashed it in lacquer thinner at my own shop, and then at the powdercoater’s shop I used his vapor blaster to get the 40+ year old Weber carb looking almost brand new!

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It’s a crazy busy time of the year for them, surprisingly. I think they do 30-40 circle track modifieds and drag race chassis per year. Just nuts how many are always in the shop. The white chassis in the pic below was just being wheeled out of the oven when I walked in the shop. At 400 degrees, it radiates a fair amount of heat!
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Pardon my ignorance Bob but what is a vapor blaster?
The carb turned out like new
 
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