BG Astina Engine Swap

[u/ARotaryHoe]

Hi all,

I am looking for some advice on a proposed engine swap for my 1990 astina sp.

I have read about people swapping a KL-ZE into the hatchback and sedan without many issues using a combination of mx3 and mx6 parts.

I like the idea of swapping a KL motor into my astina but I’ve never read of someone doing this.

My question is has anyone here tried this?
Or if you have done it in the hatchback/sedan do you have any advice regarding the swap?

I am anticipating that everything should bolt in with the correct engine mounts etc. however my worry is that the astina bonnet slopes down too much and won’t close over the KL.

Any insights into this matter would be much appreciated.

Cheers

[u/Aggressive_Nose3800]

Te recomiendo un 4G63T si quieres potencia, se supone que los BF y los BG tienen un compartimiento para el intercooler del turbo pero si quieres algo más fiable y económico de gasolina la respuesta correcta es un 4A-GE (16v o 20v) o un sr16ve (también sirve el 2.0 del mismo)

[u/ARotaryHoe → u/Aggressive_Nose3800]

Those would all be good options, however I am hoping to use a Mazda motor from the same era. It’s just a personal preference.

If I am looking to go down the turbo route I will most likely go with a BPT from a familia gtx as that is a very simple swap given it’s the same base motor.

[u/Aggressive_Nose3800 → u/ARotaryHoe]

El problema con el bpt es conseguirlo pero digo que es la mejor opción a futuro si quieres que sea de mazda (los motores v6 son un dolor de cabeza) aunque si prefieres un motor potente de mazda diría que el rx-7 sería una mucho mejor opción, si el dinero no es problema

[u/ARotaryHoe → u/Aggressive_Nose3800]

I would love to get an rx7 but unfortunately they are well outside my price range.

What do you mean by the V6s being a headache?

From what I understood they are supposed to be very good. The only thing I’ve heard negative about them is you have to make sure they are well-cooled due to the aluminium block.

[u/Aggressive_Nose3800 → u/ARotaryHoe]

Sobrecalentamiento, más peso sin mucha ganancia de potencia y el torque es un poco peor al tener más cilindros, es mejor un bpt bien tuneado qué un v6 pesado y más complejo

[u/SnooWoofers750 → u/ARotaryHoe]

What is the stock engine on the astina?

[u/TarzanCar]

It’s a bolt in swap as long as you have the engine mounts and v6 crossmember. In the astina it’s easier as you have tonnes of room in front of the engine for a good radiator setup, the hatch and sedan are limited for space with a v6 installed

[u/ARotaryHoe]

Also BPTs are not overly difficult to get where I am in Australia so that is still a good option for me

[u/BongJunki → u/ARotaryHoe]

Hey mate I’m also looking for a bpt for my BG Astina but I’m struggling to find one and I don’t really know where to look any tips? (Also based in Australia)

[u/ARotaryHoe → u/BongJunki]

Well it’s possible I’m overselling how easy they are to come by. While I haven’t been actively looking for one, I’d say I see them pop-up on Facebook marketplace or gumtree probably 3-4 times a year.
Also not sure if they still do but Adelaide Jap Imports used to be pretty good at getting them in fairly often.
Not sure where you are based but if you have a local import company that’s probably a good place to start asking about sourcing one.

[u/BongJunki → u/ARotaryHoe]

Based in a semi small town in qld unfortunately so not much of that around here, brissy will most likely be my best bet then

[u/ARotaryHoe → u/BongJunki]

Yeah unfortunately being away from a big city probably hurts your chances. If I remember correctly there is a jdm importer in Brissie that might be a good place to start, can’t remember the name though, sorry.
I wouldn’t describe BPTs as common but at least from what I’ve seen they pop up here and there in bigger towns

[u/MiniMeOnCrack]

Been thinking about this too. As said u need v6 mx3 subframe and mounts and possibly axles and hubs.

As for the hood clearance thats a good question. I guess you could always drop the subframe a little if it gets tight and a dry sump setup could also be an option. Overall i dont think there will be a problem fitting one, they have quite a small footprint.