SIII 6 cylinder to 4 cylinder conversion - Land Rovers Only

Bryan B · 08-21-2009, 10:46 AM

I have decided to change my SIII 6 cyl (RHD)to a 4 cyl. Does anyone know if there's a bellhousing adapter available? Or does anyone have an extra SIII 4 cyl bellhousing that they don't need?

Bryan B · 08-22-2009, 05:19 PM

No quick answers so I suppose that no adapter exists (I suspected that). Just posted a wtb in the classified section.

antichrist · 08-22-2009, 06:38 PM

You don't need an adapter, just get a 4cyl bell housing and swap it for the 6cyl bell housing on your gearbox.
You'll need new engine mount brackets on the chassis as well.

Bryan B · 08-23-2009, 09:10 AM

Thanks antichrist. I suspected that a 4 cyl bellhousing would be the way to go. Know where I can get one? As for the motor mounts, I'm considering my options. I am putting this all back together on a Designa coil chassis that has mounts for a 200tdi, so I think I should be close on the 4 cyl motor and transmission mounts. But as far as I can tell that leaves my transmission levers too far forward (I have 6 cyl bulkhead and tunnel). So do I move the motor and trans back to the 6 cyl position. Or is it easier to get a new tunnel and different drivelines for and leave them in the 4 cyl position? Hmm.

antichrist · 08-23-2009, 09:35 AM

If I recall correctly the 6 tunnel is different than a 4 so you can't swap the parts. The only conversion I've done to a 6 is a Perkins 4.203 so can't say for sure going to a 4cyl.
Why are you going to a 4cyl? The sixes were decent engines as long as you maintained them properly. With the side exhaust valves people tended to skip adjusting them and so they'd often end up with burned valves.
Parts are a bit harder to come by, but all the tuneup stuff is easy to find. And the rest can be found with some looking.

In any case, I think, but don't quote me, your best bet is to leave the gearbox where it is and move your 4cyl back to mate with it (with the right bellhousing of course). Your fan will be too far from the radiator, but you can easily fit an electric.

Bryan B · 08-23-2009, 12:13 PM

Good question. The number one reason - I want a diesel. Number two (and you hit the nail on the head with this one) - 6 cyl parts are a pain to find. My 6 cyl still runs pretty well (read: barely smokes), but I shudder every time I start looking at parts for a rebuild (cost, and some appear to be made of unobtanium). I figured that since I'm doing the chassis swap anyway, I might as well swap the engine while everything's apart. Also, I've already got the trans. apart to replace a bad 1-2 slider, so now is the time to change the bellhousing if I'm going to do it.

Anyway, thanks for the help. Hopefully someone can point me to a 4 cyl bellhousing so I can keep the wrenches turning.