lagging

[pulsarboby]

ive been amazed recently how many cars out there are running fmic's with no pipe lagging:shock:

this to me defeats the point of running a fmic at all. if anything it will be worse than the standard top mount cooler, due to the fact that the pipes are made of thin alluminium which absorbs heat like a sponge.

to all those that are running unlagged pipes, do yourselves a favour;-) when you have been for a run in your car, go lift the bonnet and put your hand on the intake pipe from turbo (above exhaust), it will be red hot!
during normal driving these temps will never be dropped by the intercooler itself, and will if anything be higher than the original tmic because at least the original had a nice thick hard pipe that never ran parallel across the face of the exhaust manifold.
this would be proven by anyone who has an air temp sensor fitted in line!

so bobby's little tip of the day is......get those pipes lagged (cost around £15) or dont waste your money on a fmic setup, unless you just want one because it looks good:der:

 

[youngsyp]

Here, here !! :lol:

Which reminds me, I must lag my OE turbo to I/C up pipe !!

 

[boucherie]

a good point well made bobby, ive lagged my pipe directly from the turbo and past the manifold to offer some protection from the heat but i might wrap the rest of the visible pipework as well ie the bit that runs over the gearbox.

i did used to have my air temp sensor connected just before the plenum, but now use that as a outside air temp indicator

 

[PaulB]

I just thought that when the engine is pushed hard, the reason for that pipe getting so damn hot is because the air has just come out the turbo and is bound to be hot. On the move, with all the air rushing through the grill, I couldnt really see the manifold doing much more to the pipe temp than the air from the turbo is.

I think thats what I mean :lol:

Still might lag mine though if its proven to work.

 

[boucherie]

easiest way to see how much heat comes out off the exhaust is go for a drive and then sit in traffic or pull over and see the heat haze coming straight out of the main scoop, this heat is still coming out while your driving and subsequently heats up the intercooler pipe.

if someone had enough time on there hands they could fit a sensor just past the manifold on the intercooler pipework and fit another sensor pre plenum to see what the temp drop was

 

[Fire & skill]

i wonder if armaflex would do

ive got quite a bit of it lying about

 

[pulsarboby]

I just thought that when the engine is pushed hard, the reason for that pipe getting so damn hot is because the air has just come out the turbo and is bound to be hot. On the move

only true to a small point there paul!
dont forget the air is coming from the inlet side of the compressor housing;-)
so will not be that hot!
most of the heat in that pipe is through the exhaust manifold which sits directly below it, thats why its so hot.
its simple really, if you cool the air going into the front mount, then its gonna be a damned sight cooler when it gets to your inlet manifold. so effectively the intercooler has less work to do.
and what your forgetting is the fact that heat soak is caused mainly at low speeds in traffic when there is no air rushing through the cooler, this is when you get the most heat soak.
and with engine temps being at there max in traffic, all that heat is absorbed straight into the cooler induction pipe, which in turn will reduce performance significantly!

 

[Fire & skill]

the cooler the air, the more dense it will be

 

[youngsyp]

I just thought that when the engine is pushed hard, the reason for that pipe getting so damn hot is because the air has just come out the turbo and is bound to be hot. On the move, with all the air rushing through the grill, I couldnt really see the manifold doing much more to the pipe temp than the air from the turbo is.

I think thats what I mean :lol:

Just to add to what Bob has said, the air that enters the turbo will be fairly cool. It will them be heated by the compression process in the turbo, and through the heat radiated by the hot turbo body. This will then pass through the turbo to unlagged intercooler pipe, where the temperature is maintained or increased by radiant heat from the turbo, manifold and air coming through the radiator. This will then go through the I/C core, get cooled to a certain degree and then, on it's way to the plenum, through the unlagged I/C to plenum pipe, get heated up again.

For the coolest possible charge, you need a partitioned off air filter that has a large cold air feed to it. This can then go through the MAF to turbo pipe, that's had the breather inlet deleted. And as Bob has said, have a lagged turbo to I/C and I/C to plenum pipe. And at the plenum end, delete the coolant heating circuit.

Lagging the manifold, elbow and downpipe, will further reduce under bonnet temps.

All this is very easy and fairly inexpensive to achieve. Not onlt will it increase power, torque and throttle response but, it will also reduce the chances of det !

 

[Fusion Ed]

Air from the compressor side can easily be in excess of 120deg C, much more if you push it and your turbo is running way passed its efficiency envelope.
A good intercooler will get it to around 10 deg above ambient. After ragging a pulsar most of the pipe heat is from the turbo, stick a temp sensor in it and see for yourself. Agree however that sitting still or in traffic the system will heat up by other means, as the efficiency of everything will fall with no airflow.

 

[youngsyp]

Agree however that sitting still or in traffic the system will heat up by other means, as the efficiency of everything will fall with no airflow.

To what extent would that be the case though ?
I can see you getting heatsoak in the pipe run, that are under the bonnet but, not the core itself. This would be eliminated by the pipe lagging !
Radiant heat from the rad would be pretty minimal, surely ?!

If I can prevent heatsoak on my TMIC (which I have pretty much achieved), I'm not sure it would be worth going for a FMIC then, if that's the case ?!

 

[pulsarboby]

yep agreed paul!





changed my mind, dont bother lagging the pipes its all a waste of time tbh
just let the exhaust heat them up, as the turbo gets hot anyway:roll: :lol: :lol:

 

[stumo]

the cooler the air, the more dense it will be

Does jpward breath really cold air?

 

[youngsyp]

Does jpward breath really cold air?

:lol:

Poor old JP. :doh:

 

[campbellju]

Agree in principle, disgree in implimentation.

Keeping the hot things hot is important too. get some proper lagging and sort the mainfold, turbo and downpipe.

If the ambient temperature is cooler than the outlet temperature of the compressor then it will help a little to cool the pipe.

If nothing else, lagging your manifold first stops you buring your hand on it :lol: After 5 mins I can touch the manifold lagging comfortably.

Jim

 

[pulsarboby]

yep totally agree with you jim also!
but the very least you should do, is lag that inlet to ic pipe!
by all means, if you have enough then do the ex manifold too, this will help immensely to keep under bonnet temps down and give you far better cooling through your ic.




and yes i believe jp does breathe cold air, as he lives in a country which is also dense in foilage, so his ambient temps will be well down, i may actually start calling him the iceman, he is that cool!:lol:

 

[MarkTurbo]

to all those that are running unlagged pipes, do yourselves a favour;-) when you have been for a run in your car, go lift the bonnet and put your hand on the intake pipe from turbo (above exhaust), it will be red hot!
during normal driving these temps will never be dropped by the intercooler itself:

I reckon you should rephrase that bit where you say it will NEVER drop the charge temps ;-) Thats a bit like saying during normal driving the radiator dosent drop the water temperature :lol:

 

[Fusion Ed]

To what extent would that be the case though ?
I can see you getting heatsoak in the pipe run, that are under the bonnet but, not the core itself. This would be eliminated by the pipe lagging !
Radiant heat from the rad would be pretty minimal, surely ?!

If I can prevent heatsoak on my TMIC (which I have pretty much achieved), I'm not sure it would be worth going for a FMIC then, if that's the case ?!

Its not possible to prevent heat soak on the core itself on the top mount intercooler. The fact that air from the top bonnet enters it and leaves the intercooler by the bottom means that the opposite is be true when your stationary or the forward airflow is not enough to cancel out the convection of the heat rising from the core. There are many reasons why a top mount IC is not good. If you were to look at the airflow over the car in a wind tunnel you would see some of the reasons why. Essentially the only way to keep the boost pipework short and have the core on top is to turn to charge cooling and have a rad on the front, otherwise your only other choice is to front mount it.

IIRC you loose roughly 3% power for every 10deg intake temp rises. Also you are much more likely to experience knock if the intake charge gets too hot. This is more of an issue than the power loss itself. Both combined have the potential to create quite a nasty situation.

Another interesting point is that the engine has no idea what temp the intake charge is since its being measured as it passed the airflow meter. This is why the engine responds so well to extra ignition when you have a front mount as the huge buffer zone on the stock map can be made more sensible.

Bottom line is if your intake charge temp maintains roughly 10deg above ambient you have a pretty good setup and nothing needs to change.

 

[Trip]

What about a standard top mount with those C02 spray bars? But you do not want any c02 to be ingested in the intake.

 

[pulsarboby]

I reckon you should rephrase that bit where you say it will NEVER drop the charge temps ;-) Thats a bit like saying during normal driving the radiator dosent drop the water temperature :lol:

you know what i mean markie:roll:
of course the temps will drop, (unless your stuck in traffic) but they will drop even more if you never had a dirty great exposed red hot manifold stuck right underneath the inlet to the ic, does kind of defeat the object of the fmic a little:-D