DIY Exhaust

So I have an MOT to get through.

My exhaust has rotten through just behind the mid box. So I order a new mid box. As I was fitting that, I found the front pipe had also rotten through at the elbow coming down off the turbo. So I've got a new one of those.


The new pipe and the old pipe are not the same. The car WAS a v8 petrol, and is now a 300tdi. There are bits and pieces left over and getting the right parts can be hard, and the old exhaust is almost certainly welded to fit. I'm in the mod to extend and change the 'new' front pipe so that it fits.

At the moment I'm thinking the flexible sections available online that you weld in. Easy and simple. I will need one to join the cut I need to make the elbow section the right length, and one to extend the main part as it's too short.

Does anyone want to weight in before i cock this up?

Try and put together something with as many standard parts as possible, makes next change simpler.

If they have only changed the engine you should be able to get a standard 1 to fit.

The only thing I done was to have a rear straight through pipe as the box by the mud flaps kept rotting out.

Hicap phill said:

If they have only changed the engine you should be able to get a standard 1 to fit.

The only thing I done was to have a rear straight through pipe as the box by the mud flaps kept rotting out.

Click to expand...

I keep thinking that, But I just can't seem to find the right front pipe to fit, and it's costing me time more than money to keep trying different ones.

The pipe I have taken off has to be a welded job, as it has the correct end to fit the 300tdi turbo (3 bolts + gasket) - and the right end to fit the middle box that was on the car (3 bolts with collar). A 300tdi front pipe has 3 bolts one end, and then two at the other. So while I think it would be best to not muck about welding things and having the same problem next time - I'm going to do it now, and regret it later.

I’m lucky we have an exhaust manufacture near me who builds to suit. Mines a 200disco into a 110. Down pipe has been cut and angled more

I’m sure @bankz5152 built his own.yes it may be a td5 but he may know where to get the correct items from

@NiallRussell rattled my brain & this is who I use for racing parts.
So what you need is a down pipe cut & re welded with your flexi.? You have the ends on the old exhaust

It costs as much to make your own standard one as it does to buy new.

Just bought a new oem spec mid box and rear box for a customers 90, £150.

My 3" downpipe and rear pipe cost £180 in materials...

If your engine is in the standard 300tdo position, right up to the radiator, then a standard 300tdi pipe should fit.
Where does it foul? If you can't actually get it in place, you have to jack the front end up slightly, to open up the gap between the axle and chassis.

I had a long talk to my wife about this - and she has correctly persuaded me to buy a complete 300tdi exhaust system (not much money) and replace totally, so I won't have this problem again. Pitty as I enjoy the process of bodging things, but my bodges are terrible.

Just thought I would put a little update here. I ended up having to do some mucking about with new mounts as I didn't really think through all the repercussions. I bought the little mounting hooks and the rubber and it was easy enough.

Then I discovered that the engine is clearly a little aft of where it should be. Or the gearbox mount is, but either way the front pipe wouldn't fit, The 'bend' wasn't right and it was too long, it just couldn't weave past the gearbox mount, and fit to the turbo. I ended up cutting the front tube, shortening it, and rotating it slightly when i put it back together with a clamp. Easy and worked perfectly.


There is a slight 'twist' on the box, but it doesn't add up to much.


This is the clamp. was about £15, didn't feel like welding it, as it was much easier to loose clamp it and rotate it to the perfect path once fitting. Then just nipped it up.


I need to do a hanger here of the transfer box bolt. It's a common mod (as far as I believe), where it just hangs of the same bolt that currently has the speedo cable tidied away.


Gearbox mount


managed to get it to fit through nicely


Had to use a ton of spacers to get the exit pipe free of the body work


just for reference here is what i took off.