75wagon's GD sedan, now wagon project...

[turbosigma]

thermostat housing - check some of the 4 cylinder Toyota's. They have a removable remote thermostat.

If your interested will try and get a pic.

[geezer101]

Full points for lathe turning a plug from timber Dave! And then using the plug to recut the resin once it's dried... Nice work

[75wagon]

A little bit each night is the best way to get a big job done.
Here's one step further...
I rubbed back the glass filler layer, and gave the mould a try. I need to gelcoat the finished item, carbon material just wont work for this kind of shape






This is still only early stages, I have learned a lot from this mould pull. I need to do a shorter first lay up, I'm losing the step as it drys.
As long as you learn something everyday, it's a good day

I'm still trying to work out the best way to form up a mould for an equal length intake manifold.
My current way of thinking is to make one out of carbon fibre. I have the resin to withstand heat and chemical so once I have the mould build method sorted, I should be sweet as
The aluminium manifold is something I have decided not to pursue anymore, it's too difficult to get a free flowing equal intake length manifold.

Dave...

[75wagon]

Here's what I'm up to.
I've managed to successfully pull a tube off my mould. Unfortunately, the mould I'm using isn't smooth enough, so I have to rub them back.






That lip is damn difficult in fibreglass.

[75wagon]

4th Velocity tube finished today.

4 tubes cut and ready to join


Joined and placed back on the carbs so they dry straight and properly spaced


Underside view of carbs showing joining method


Next job, design and construct my plenum, the narrower the better as it will give me more room so that my intake runners can be as long as possible. 280mm from head to strut tower doesn't give me much room to play with which is why I'm going to run a remote filter housing.

[75wagon]

I'm now working on the final design of the remote air cleaner that will also house the battery, in an almost factory location.












There is plenty of work to do still, and there is plenty still to work out.
I am using a VL Commodore EFI airfilter, and MDF to construct the box. Once it's all cut out I'll be fibreglassing the box together, and then laying up carbon fibre over the top.

[Benharjon]

Looking Great Mate! Cant wait to see the finished box!

[A112H]

Just a thought looking at the pics. Have you got enough height clearance between the bonnet and the battery to lay the air box flat and sit the battery on it?

[geezer101]

Just a thought looking at the pics. Have you got enough height clearance between the bonnet and the battery to lay the air box flat and sit the battery on it?

Oooooh, so many bad design flaws in that idea I don't know where to begin... Pulling the battery out to replace a filter? The weight of the battery on the filter enclosure? What about the occasional splash of acid when checking/topping up the battery? I think Dave's on the right path with a remote panel filter. It will be compact enough to sit in there with minimal hatchet work. If you can make it into a drop in/pull out cartridge that will seal up properly, it'll be a winner.

[75wagon]

Have you got enough height clearance between the bonnet and the battery to lay the air box flat and sit the battery on it?

I thought I had made all the crucial measurements, but it seems I was a bit out.
I've had to lose the front panel of the airbox I was making due to battery to bonnet clearances.
I've been reduced down to 85mm from the radiator support panel from what I though was 110mm. I have lost this due to the front wheel arch. The further I go back, the higher the battery has to sit.
There isn't anyway possible that I could raise the battery any higher (which is what i'd have to do to fit the filter flat under it). I have a 30mm space in the void under the battery, but the gap inside the box I have constructed is 30mm ID. For the filter to work and have enough flow under the battery, I'de have to have more then double that, and the battery would be poking through the bonnet.

I'm dealing with a pretty tight space, and I didn't realise exactly how tight till today.
I hope to have this sorted and finished off soon, then I can start constructing my intake plenum, and intake manifold also. I can just imagine how much fun that is going to be

[75wagon]

I've done a bit more and it shows more of the complete design.

[A112H]

Looks good, where does the intake come from?

[75wagon]

Looks good, where does the intake come from?

For air flow into the filter housing the best I can do is to pull the intake air through the headlight holes, and more from above the radiator support panel.
There is more shrouding to go around the front (in an attempt so it separates the intake air from that in the engine bay).

If you mean where does my intake for the carbs come from to mate up with the back of the filter set up, well it doesn't exist yet, that's the next job, but from trial fitments it should be pretty much inline with the outlet from the filter box, but it will be higher. I purposely kept the outlet low so that the distributor is easily accessible.

[75wagon]

I've spent the day on this...
The worst part is that nothing in the engine bay is square, so nothing is easy to make to fit in there.
The amount of time I have spent trying to profile things to meet up with the panel work is unbelievable.


Revised battery carrier has changed a lot of things, but at least now, I wont be limited to what battery I can run






Due to not enough measuring, I ended up losing the front of the box that I wanted to run, so I have tried to compensate by maximising the shape of the filter housing to the shape of the car. This way, I should be able to make the most of any available air coming into the front, and hopefully, at freeway speeds even be able to create some positive pressure in the intake.


I've raised the top of the intake filter hosing to try to maximise natural airflow.








Unfortunately I've had to interfere with the outlet size due to battery size.




Start of carbon fibre lay up...

[gaPhil]

Impressive, looks awesome mate!

[Benharjon]

Great work mate, Its gonna look real impressive when its done! Interesting to see how effective it is too! Keep it up

[ISKA8]

Hey dave how are buds,been a while since ive been on,nice to see the build is in the process and coming up great..as you might already know i gave the sigma to my little brother as a birthday present and we also bought the quad carb setup like your,just want to know how much room you have between the webbers and the strut tower once bolted up? i noticed that you have made fibreglass trumpets but do the stick up or point towards the strut tower?

[75wagon]

Good to see you back on ISKA8

just want to know how much room you have between the webbers and the strut tower once bolted up?

I have 280mm between the block and the strut tower. I am going to make the intake manifold myself, and also an intake plenum that matches up with the remote air filter that I am constructing in the pics above.
It doesn't give me a lot of room, but I am going to try to make the intake runners as long as I possibly can. I am aiming for 120mm but we'll see how it ends up. I collected some stuff today to start construction of the intake manifold, it's going to be time consuming and complicated, but I hope to end up with a good result. I will be making it from Fibreglass/Carbon with a chemical and heat resistant resin, it should prove an interesting experience, I am learning more an more about glassing the more I do. I did a 2 year polymer processing course that I completed back in 2000. This is the first time I have used that I learned.

i noticed that you have made fibreglass trumpets but do the stick up or point towards the strut tower?

Towards the tower.

nice to see the build is in the process and coming up great

Progress is slow, and this is just the thin edge of the wedge, there is so much more to do, I just want to get past the stuff I'm unsure about first then move onto paint and panel.

Dave...

[ISKA8]

cheers for that Dave..i actually bought the carbies off a guy from this forum and they already have runners on the with the manifold plate..hmm ill measure the runners and see what room i have left,if any..oh and its nice to be back even though i dont own the siggy no more but still in the famil..lol

[A112H]

Just noticed something Dave, how will you replace the filter? I think it was either late model Evo's or Toyota Aristo's that have a similar set up and they have a door/flap set up on the top. You just open it and the filter slides in and out like a toaster. Might be too late for that but an idea anyway

[Scorpma82]

OOOOOOOh , make sure you put in a crumpet setting in ur airbox then

[75wagon]

how will you replace the filter?

All I was planning to do was remove the housing

[Scorpma82]

as a suggestion.....cout you cut the top section off on the air box and put in some form of door hinge?.....so it fold open at ur discression?

[75wagon]

cut the top section off on the air box and put in some form of door hinge?

Why would I do that?
Isn't the idea to create positive pressure in the intake? Wouldn't introducing a hinge create an air leak?
I'm also playing with millimetres, I have made the box the largest I can, any more additions may cause clearance problems?
Just so you guys know, the plan is to make a scoop/funnel that sits behind the grille that captures as much air as possible, so hopefully, at highway cruising speeds, I can create a positive pressure in the intake, and therefore maximise throttle response... well that's the plan anyway

[Scorpma82]

OH im not saying anything -ve....i think its a great design......but i was thinking (not that i mentioned it) that you couls maybe line edging with a rubber seal....i don't know

But i'm guessing you'd want resonably easy access to what a rather disposabke unit.....even if the filter is washable, you'll be removing it just as often as any other air filter unit.


None the less, great work....looking forward to see how it blends into the engine bay

[75wagon]

Shit just got serious.
Phase 2 starts now.
Original carb and manifold is out as of this morning, now I can see for certain, exactly what room I have.






Working out approximate location for the carbs...


The space between the carbs and the remote air filter outlet isn't all that big? Looks like that piping will be pretty short :/

but i was thinking (not that i mentioned it) that you couls maybe line edging with a rubber seal

That's what I'm planning to do.

[75wagon]

Started making my jig for the intake mould.


That's a 60mm lift, with a 15 deg angle for the carb positioning.












I originally planned to use flexible conduit, but it ended up being a failure.
I switched to cardboard rings, using a flexible tube to locate, then masking taping the outside to hole the desired shape. All the pipes are approximately the same length, and actually share the same curvature, the only thing changing is the rotation of the pipe.
Next step is to apply bog to the outside and sand smooth, doing my best to keep a constant 40mm ID...
I then need to make the cooling ducts, and thermostat housing

[geezer101]

I switched to cardboard rings, using a flexible tube to locate, then masking taping the outside to hole the desired shape.

Did you see this idea somewhere or did you come up with it? Either way it is a unique bit of lateral thinking to jig up a section of pipe. I think you're going to be forced to make even shorter runners to accomodate the plenum...

[75wagon]

Did you see this idea somewhere or did you come up with it?

I originally came up with the idea of MDF discs with rubber tubing on wire. But decided it was too much work by the time I filled it all up.
After I had the failure with the flexible conduit today, it was just a case of I had cardboard on the table, and had the hole saw out. It started as a bit of a joke, but it's actually working quite well.
And no, I hadn't seen it before, like always necessity was the mother of invention.

Dave...

[A112H]

Any reason you couldn't space the carbs further apart so you could run straight pipes into the head?