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E- mail sent     gmholdman.

Thanks RET... I'll investigate a bit further.... I think that mod was done about 20 years ago and the bloke who did it has unfortunately passed away.

Cheers,
JayJay

Thanks but the part that is broken is the stub that is attached to the metal part of the vent window I will have to try and get a complete assembly or try to silver solder maybe.
Found an assembly but they are asking a ridiculous price for it. I'll see how i go repairing it.
 

If you get stuck, here is one option:

https://www.kingswoodcountry.com.au/buy/holden-vent-window-handle-fe-fc-fb-ek-pair.-quarte/VH1001

Cheers,
Harv

I have nearly finished my build but I have a broken FC LHS vent lock any able to help me out?

I admire your knack of making complex stuff understandable to a dill like me 😃


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Craig,

You wrote, "you will need to rejet the carbys or they will run rich as you are doubling the fuel intake which will be too rich at idle/low revs and foul plugs"

This is a common misconception, but in fact isn't true. 

This got me thinking. Bear with me... I've been trying to dissolve some of this fluid mechanics stuff in ethanol for the last 30 years.

There is some complexity here when changing from singles to twins (or triples, or fourtles  ). The inlet manifold flow path is very different, and gas density changes in venturis can screw with Bernouli's ideal world venturi model. Ignore that for now, as grey motors are not that precise.

Agree that the main jetting should be very, very close to needing no change when going from singles to twins or triples (or fourtles). The trick here is that the venturi pressure drop is dependant on the square of the gas flow through it. That same pressure differential is what the main metering jet sees. The liquid flow through the main metering jet is dependant on the square root of the flow through it. Simplifying the mefs, the square and the square root cancel each other out. This means that no matter how many carbs you add, as long as they see their equal flow of gas, they will meter the same amout of fuel.

The power bypass valve system is driven by the same pressure differential, so in theory no need to change the power valve either.

But...

The above applies to the main metering system, which is driven by the venturi. The idle system is not... it is driven by the inlet manifold pressure (this is because the main metering jet discharges into the venturi, whilst the idle system discharges into the throttle body. Simplifying a bit, the inlet manifold pressure does not change much with singles, twins, triples or fourtles. Adding more carbs, they all see the inlet manifold pressure, and they all deliver (roughly) the same idle fuel flow as a single. This means that when going to twins, you need to wind the idle system right down. There is an overlap between the idle system and main metering system, so getting the idle right not only effects the idle quality but also the main metering quality. If you are lucky, there is enough finesse in the idle mixture screws to rest the idle after going to twins, triples or fourtles. If you are unlucky the idle mixture screw is not so fine when it is close to it's seat. In that case a change to the idle tube is required.

The accelerator pumps are independent (roughly) of vacuum, but with twins, triples or fourtles you now have twice, double or four times the fuel shot each time the loud pedal is depressed. The pump circuit thus needs a tweak to deliver less fuel, though for a relatively rough grey motor the average owner won't notice a difference.

Cheers,
Harv

Hi JayJay,

It's beyond doubt that the tunnel has been modified to allow that gearbox to fit. The only non-grey gearbox I am aware of that you fit in the stock tunnel is a 4-speed from a Datsun 1600. (There is also possibly an MG 4 speed that fits, not 100% sure of this.)

The EK auto had a much bigger hump than the manual FE-EK to accommodate a Hydramatic, and this was always the go-to floor alteration back in the day. But EK auto floors aren't easy to come by any more, so fabricating your own seems to be the route most people have to take these days.

All of which is to say yes, your floor must have been modified. Will it fit a Trimatic? Probably, the Celica box is a fair size. If your car has an EK floor, a Trimatic will definitely fit.

If you can post a photo of the floor someone can probably tell you whether it looks like it was an EK hump. But if it was fabricated from scratch, you might have to get under it with a tape measure.

Hope that's some help.

cheers
RET

G'day Everyone,

I recently bought an FC Special Sedan which already had a Celica 5 speed transmission behind a red motor installed.

Would it be correct that the tunnel had to be modified somewhat to accommodate this?

Also, if I wanted to swap out the Celica 5 speed for an auto, would a trimatic fit without any additional modification to the tunnel?

If not, is there another auto which would fit in that space without further mods to the tunnel.

Thanks for your help!

I tried to get some from SpeedSpares but they are an item which is on back order... I ordered them in January and they still haven't come in so I just cancelled the order.

I would try contacting them first to see if they have an update on when these will be available.

Cheers!