Question ❓ those that have "hotted" up there g150. What sort of power figures are you getting?
Thanks Sean?

That's like asking a lady what colour knicker's is she wearing.

Nah just how big the skid marks are in them

I was hoping you would see the funny side of it. I have dyno sheet somewhere from 1 of mine running twin webers. Wasn't big figures but it revs pretty hard. I was a little let down at first by the figure but driveline 14 inch wheels and so on dyno Guy said close to 100hp flywheel. I think the twin cam is around 120hp and little hottie will feel as good under foot. In saying this I have a hottie a 2ltr twin cam and a 1800 twin cam and the 1800 eats the 2 litre no question.

I do have a sense of humour on a Friday 100hp sounds good, I'd be happy with that . The thought of engine swaps had crossed my mind but really want to keep it pretty original

bore them out 1600 Gemini pistons and rods depending on the pistons watch your deck clearances. This will lift your compression a little. some head work and get them breathing. They go all right.

Got a specific piston kit to keep an eye out for?

Someone might
I use second hand 1600 rods. As for Pistons? some have been fine others have needed decking. Depends on pin location I think.

A road / race version round this way had 1.6 Gemini pistons and rods, head work, decent cam, the normal stuff, and did 122 at the flywheel with twin Webers.
The Webers were way too big and the manifold was too short, so a swap to 1.5 inch SU's and a long manifold gave a bit more. Wasn't dynoed with that set up but you feel the difference driving it.
The EFI 2.0 twin can was 124hp from new, and a change to Webers will give another 10 without a touching it. A Gemini 1.8 OHC with the right head, cam, Webers, exhaust etc will give 150 odd all day, so 120 is pretty good from a 1.5 OHV if you still want it drivable.

1.8 vs 2.0 is an easy answer.
1.8 has the same stroke as a 1.6, so revs hard. Gives more HP but you have to thrash it.
2.0 has more stroke so doesn't rev as well, but give more down low.
Under 6000 rpm I'd have a 2.0, over that go 1.8. That's why the Gemini guys use the G180 SOHC, hang a huge turbo off them and see 8 - 900 HP and get 9 second qtr mile times and upwards of 150mph trap speeds.
1.6 will rev its nuts off but doesnt have the capacity to make matching or better HP. 1.5 is even worse off.

new Gem pistons are getting much harder to find, according to local engine re-builder.

Good info guys how much do the bores have left after the Gemini pistons?

Tons.
Just makes them the same as the GT.

Donkey's G150 3b is stock other than some headwork (shaved 1.3mm, intake mildly ported, exhaust somewhat extensively ported and heavier single piece Ford Courier valve springs) and he goes pretty well but starts to starve of fuel at about 5500-6500RPM.
I now also have a freshly rebuilt set of twin 1.5 SU's ready to bolt on (short manifold unfortunately but plan to modify later) + I also have a NOS distributor and elecy ingnition set to go on at same time. Fan will be gone and a thermo fan fitted in it's place, new bigger exhaust pipe going in (std exhaust manifold being retained for now as they flow pretty well anyway) and a bigger elec fuel pump for a bit more flow at top end rev (which is where Donkey lives most of the time)
He will then go on the dyno once it's all done and I will let you all know the results then.

He will also be getting a custom alloy 60Ltr fuel tank too, ready for some epicly long road trippin

Something to look forward to. Unlike the body work. have I mentioned before I hate frigging rust? What's the best gemini piston set to keep an eye out for? standard,flat top, domes? There is a set of standard type on ebay atm. Also seeing as I'm asking a million questions I've got another, what 5 speed is the best option?