Blowing/diesel noise?

Thats the best way i can describe it! You know the old style diesel engines? that sound like a tank? why does mine sound like this? on tickover its fine when reved its still ok-ish but when your low down in the gears building up speed it sounds bloody awful!!

Just had a stainless 4 branch fitted and while it was on the ramps you could here it then, although little bit strange…it kinda sounded like you could hear the exhaust fumes through the manifold?…i dont know i think it may be bottom end but it drives like a dream! carb may need setting up properly but any ideas what it could be? running on 3 cylinders?

there's deffinalty no leakage in the exhaust system.

There's a pipe from the downpipe back to the carb, mine went sounded like a tractor… Check yours they normally have a flexible pipe in the that splits

As above

Exhaust fumes on a 1.3 run through the head  and into the inlet then back down into the downpipe via braided pipe. So you need to block this off at the bottom of the inlet.

hope that makes sense.

Is it worth getting rid of that pipe?
mine has been welded a few times and is holding but next time it goes im looking to just delete it completely. If it serves a good purpose then ill try and keep it

I would keep it if you can. I suggested blocking because there is no real way to attach it to the new 4 branch.

Ahh yeah, just ive known people to remove it completely when it falls off  

I've removed mine! Just takes a little longer to start from cold and warm up!