Water heated inlet plumbing

Post by **winger300** » Wed Sep 26, 2007 12:39 pm

I have a "Daytona" inlet manifold, identical to the Minispares one with the water pipe fitting.

But how sould I connect it on my Series II? I dont have a water pump bypass hose, so the only place I can see to connect it is on the heater tap somehow?

What size water hose should be used?

Thanks

Post by **bmcecosse** » Wed Sep 26, 2007 1:38 pm

Don't bother - leave it unconnected - the colder the ingoing charge, the better. Yes in winter you may see some ice forming on the outside of the manifold - but don't worry - it'll work fine.

Post by **winger300** » Wed Sep 26, 2007 3:40 pm

is it not better for fuel economy?

Post by **picky** » Wed Sep 26, 2007 4:59 pm

having hot water going through the manifold will increase economy and reduce power, as the heat vaporizes the fuel better, but also reduces the density of the charge - so less charge gets into the cylinders. One of the advantages of fitting a water cooled inlet manifold is so that you can disconnect the heating facility - a bit more difficult when the inlet is cast with the exhaust! I found that a 1098 without any inlet heating connected is very rough running in winter when first started. if you connect it inline with the heater, then turning on/off the heater also turns the manifold heating on/off... so if its cold enough to have the heater on then the engine gets a heater too!!

Picky

Post by **winger300** » Wed Sep 26, 2007 6:59 pm

That's what I was thinking... so where can I buy the hoses? and what do I need to buy?

The pipe to the heater tap needs extending to the manifold, how can I connect another pipe up to it?

Post by **picky** » Wed Sep 26, 2007 7:15 pm

should be able to buy rubber hose by the metre from a motor factors... measure what inside diameter would fit. So you need one piece leading from your heater tap to the manifold, and then another piece leading from the other end of the manifold all the way to the heater. about 2metres should be long enough I think?

Picky

Post by **bmcecosse** » Wed Sep 26, 2007 7:59 pm

If you really MUST connect it - just take the hose off the tap and extend it to one of the pipes on the manifold - then run a new hose from the other pipe - back to the tap. Note this will rob some heat from your already miserable heater - you may prefer to try to use the water after it has flowed through the heater - but then it won't be very hot!
Really - it won't make any great difference to the running if you don't connect it - and all the twin carb A series engines (Spridget/MG1100/Cooper S etc etc) mangaged just fine with NO inlet heating - in some cases this lack of heating was the only reason the engine managed to develop a wee bit more power over the standard version. The cold inlet charge on a standard engine is worth 2 maybe 3 bhp - and if the manifold also flows better and has a bigger/better flowing carb then add another 3 bhp for that.

Post by **alex_holden** » Wed Sep 26, 2007 8:46 pm

bmcecosse wrote:you may prefer to try to use the water after it has flowed through the heater - but then it won't be very hot!

Surely the jacket doesn't need to be very hot if it's mainly there to stop the manifold getting so cold it ices up? Plumbing it into the return sounds like a good plan to me.

Post by **bmcecosse** » Wed Sep 26, 2007 9:23 pm

Aye - it's just a bit more difficult to intercept the flow that way round! Mine is not connected - and most Mini owners never connect these. the ice that may form on the manifold does no harm - it's not the same as carb icing which can only be cured by feeding hot air into the carb. Heat from the manifold will never travel back to the carb against the gale of freezing cold air and rapidly evaporating fuel rushing in the way - and there's a plastic insulating block too just to make sure !!

Post by **Roni** » Wed Sep 26, 2007 10:57 pm

Mine is plumbed in after the heater. Without the heater on the manifold has no water through it and the car is a real choke addict and takes a while to warm and run properly. With water through the manifold,heater on, it is much quicker to warm and give stable running. Once it is warm and out on the open road it seems to run better with no water flow through the manifold.

Post by **RogerRust** » Thu Sep 27, 2007 8:25 am

So I should remove the ugly copper pipe and connect the heater connection on the bottom hose to the front of the manifold and the rear of the manifold to the heater and then through the heater back to the valve at the back of the cylinder head?

Post by **bmcecosse** » Thu Sep 27, 2007 10:53 am

That's it!