18 replies to this topic

[doormatt]

Right so due to the standard exhaust on my car being so old and broken that it is now unusable I have bought myself a brand new straight through centre exit twin DTM pipe with an LCB manifold. As I am new to minis I did not realise that the exhaust manifold and inlet manifold were joined on the original system so I did not order a new inlet manifold. I asked a friend who has plenty of experience with minis and he told me to get the water heated inlet manifold from minispares which I have just ordered. What I am not sure about is what the two black pipes which stick out the side are for, and if they are water pipes. I don't think my current inlet manifold has water pipes so what do I do?

 

I am doing this work at a friends garage but I'm going away next week so I need to get it done ASAP as I can't leave my car there for a week.

[jime17]

They are water pipes and they require plumbing into the cooling system to function.

I assume you can leave them disconnected though if you want to use the car straight away. Not sure its truly necessary in this country to heat the manifold. Someone will confirm or pour scorn on all of this im sure

[Tamworthbay]

Some people connect them but most don't. Just bypass it and there is no problem.

[beaker the muppet]

yeah makes sense, those are just for heating the inlet manifold, given that the days are significantly warmer now it won’t make any difference if the manifold is heated or not.... i think

 

if your mini doesn’t have heated manifold at the moment then just fit the new manifold and ignore the heating pipes until you have a chance to sort it out properly.

[klivins]

I had them not connected with no ill effects. When after 3 years I decided to plumb them in, now the choke needed for very short time only. I think, if the manifold has been designed to have water cooling, it certainly performs better when plumbed in.

[doormatt]

Thanks guys

[Mini Manannán]

I had them not connected with no ill effects. When after 3 years I decided to plumb them in, now the choke needed for very short time only. I think, if the manifold has been designed to have water cooling, it certainly performs better when plumbed in.

 

It's not designed for water cooling, it's for water heating the fuel/air mixture.  It had been discussed two or three times in the short time I've been on TMF.

[Tamworthbay]

I had them not connected with no ill effects. When after 3 years I decided to plumb them in, now the choke needed for very short time only. I think, if the manifold has been designed to have water cooling, it certainly performs better when plumbed in.

 
It's not designed for water cooling, it's for water heating the fuel/air mixture.  It had been discussed two or three times in the short time I've been on TMF.

Indeed it has and the main thing that seems to get heated is the discussion. What most people seem able to agree on is that it doesn't make a great deal of difference either way.

OP- if you want to know more on the pros and cons just do a quick search and as MM says there are a few threads.

[klivins]

I would tend to think it can do both, heating and cooling. For instance, if on hot day steaming uphill, your exaust manifold can be red hot, and transfer its temperature to nearby inlet manifold (esp. on standart setup). Having manifold plumbed in water cooling system makes manifold and carb very stable temperature wise.

[Cooperman]

To change the subject slightly, I hope the OP realises that a twin exit DTM exhaust will lose him a few bhp. Not exactly the ideal design of exhaust when compared to performance exhausts like the Maniflow or RC40.

[Gremlin]

To add you may want to alter the fuelling and timing

[doormatt]

Yeah I've realised about the fuelling and timing. And I'm not too bothered about the slight power loss, I got the twin DTM for its looks and sound. And I guess the verdict is that I don't need to worry too much about the two pipes

[Gremlin]

Leave them off permanently, the coolant takes a while to warm up and the exhaust manifold heat will radiate up anyway

[Mini 360]

To change the subject slightly, I hope the OP realises that a twin exit DTM exhaust will lose him a few bhp. Not exactly the ideal design of exhaust when compared to performance exhausts like the Maniflow or RC40.

Not everyone wants 100% performance from everything.

[Mini Manannán]

Or do this to it: