LJ80 motor compatible with SJ410 four-speed gearbox?

[SteveD]

I saw somewhere that a gearbox from the four-speed sj410 would bolt right up to the lj80 motor. Anyone know if that is true? Thanks, Steve

[juncopartner]

The SJ410 bolts straight up with almost no mods.
There are actually two types of gearbox, an early model (up to about 1985ish), which is much smaller and similar to an LJ box, and the later much larger gearbox. The later one has a shorter input shaft and has the spigot bearing in the flywheel, while the earlier one has a longer input shaft and the spigot bearing was in the end of the crank.
The early type bolts straight up, but the later type you will need to fit a later type SJ flywheel or get the LJ flywheel machined to fit a bearing (I think its a 6200 2RS bearing from memory, I'll see if I can find a flywheel lying around to check). If you don't fit this bearing your gearbox it willl self destruct very quickly!!!

[juncopartner]

Should have added that this is based on Japanese built gearboxes. Never had anything to do with Spanish built ones.

[ScottieJ]

If you are planning on fitting the sj410 gearbox into an LJ there's a lot of work involved, bolting it up to the engine is the easy bit. You will need to cut out old mounts and fabricate new ones as well a making a new propshaft. You might also need to modify the transmission tunnel. Tbh I'm not sure it's worth the hassle unless you are fitting a 5speed gearbox but you might as well also fit an f10a for a bit of extra power. Or just jump to a 1.3/1.6 with a 413 gearbox as it won't be that much more work.

[Anton]

Or just jump to a 1.3/1.6 with a 413 gearbox as it won't be that much more work.

This is what went through my head - if you're going to go to all that trouble, you may as well go with something that makes the thing drive as nicely as possible.

I think someone even posted recently that they have a 1.3 gearbox mated up to a 1.6 for sale, didn't they? Or am I hallucinating?

[donkeychomp]

Yes but that was an entire LJ! The vit engine wit an SJ 5 speed box transforms an LJ into a ballistic missile. The performance is incredible compared to an 800cc lump. Deffo the option to go for!

[ScottieJ]

Imo it all depends what you want, if it's modified and just a toy then it's a good choice, If it's a tidy LJ80 then there's no way I would cut it up to fit a 1.6! There's very few original LJs left in the UK, nearly all of them have been modified.

There quite a few Chassis and body bods needed.