The other day I was chatting to someone who had chosen to wrap the intake pipework of a CAI with a gold tape to reduce the heat absorption and ensure the air getting into the system was as cold as could be. Given the temperatures in modern petrol cars can generate under the bonnet this seemed to be a very wise choice of modification, so I decided to go away and investigate further.
For years there have been various products available for reducing underbonnet temperatures. Exhaust wraps, reflector blankets, firewall plates, high performance cooling system additives etc., and I wondered what else was available, and why these days no one seems to use this stuff to counter heatsoak. People spend small fortunes on twintercoolers or enhanced FMIC's, which although VERY worthy are actually on half of the story. The IC's only go some way to rectifying intake temps rather than resolving heat related issues at the root cause of the problem.
There is a site I've found, courtesy of a member on another forum, called: http://www.agriemach.com/
There are a range of products for wrapping exhausts, intake pipes, electrical protection, blankets etc...
Products that particularly caught my eye were:
1) Titanium exhaust wrap (link)
2) 4 cyl turbo insulating kit (link)
3) Pipe heat shield (link)
4) Reflect-a-gold pipe wrap tape (link)
5) Radiator relief cooling products (link)
It is widely accepted that heat not only robs engine power / efficiency, but excessive heat reduces the lifespan of underbonnet electrical and mechanical components. Whilst tolerances for this will be factored in to cars during the development phases of OEM testing, when the consumer decided to go for stage 1, 2, or 3 modifications there is a natural requirement to increase the capacity to cool things down.
What can I get for free?
There are some very basic 'for free' things you can do, which include careful driving during start up and warm down. Ragging your engine whilst cold (when the engine has not had time to circulate / thin the oil) is a major contributor to wear and damage. Less known is that by having a managed approach or 'cool down' regime, by running the car at much lower RPM for the last few minutes of your journey also helps tremendously. The oil can continue to run around the turbo as it cools meaning you get less coking of the oil in the turbo once it stops pumping (particularly if you car doesn't have a timed pump system). A high quality oil which is changed regularly will help to increase the life of your turbo. This heat up / cool down process will extend performance and longevity, but will not specifically reduce under bonnet temps.
Phenolic gaskets
Another product that seems to be recommended by serious enthusiasts, although it is something I would personally change unless the OEM product failed is a phenolic inlet manifold gasket. This heat insulated gasket stops the transfer of heat from the main block into the inlet manifold again reducing intake temps.
WMI
More recently we have seen the use in the UK of WMI (Water Methanol Injection systems), which inject a constant controlled flow of water/meths into the intercooler. These significantly increase the density of the intake air, and reduce the intake temps and the effects of detonation. Whilst a very useful mod, the only problem I see with this is that you have a supply side issue where you are having to constantly top up / purchase methanol. Whilst I see the benefit completely for track days or performance runs, unless you have a very large reserve tank it could become a burden over time for high mile daily drivers.
NOS
N20, or Nitrous Oxide causes a large drop in intake charge temperature, resulting in a denser charge, further allowing more air/fuel mixture to enter the cylinder. Nitrous oxide is sometimes injected into (or prior to) the intake manifold, whereas other systems directly inject right before the cylinder (direct port injection) to increase power. Personally, again as you are carrying tanks (which need refilling), it's not a route I'd go down (particularly as I run cars which are within a warrantable window). Street racers and Fast & Furious types will go giddy for it, but although its become a more progressive technology in recent years its still a bit of a one pop shot for my liking.
Cold Air Intakes
Various companies offer CAI's, and with the eagerly awaited Forge Twintake we will shortly be seeing another evolution of this product genre come to market. Getting a pure cold air intake feed under the bonnet is not easy, as the CAI itself will attract heat from the high underbonnet temps. If you run an open cone system with shrouding you will inevitably get some engine heat filtering back into the system. Getting good cold air fed to the filter from optimized vantage points (front fog vents), inner wing arches etc. can be useful (use good quality flexi hose - heat insulated), but beware of potential water ingress. Always recommended as the OEM systems are often restrictive, particularly now engine covers are used to house the air filter. As VAG cars don't have bonnet venting as standard you are always fighting the tide!
Lower temperature heat range spark plugs
Many tuners recommend running a spark plug which is one heat range below the OEM one when your car is heavily modified. I must admit I am not entirely sure what the outright benefit of this is, and can only assume that the detonation process with the richer fuel / air intake benefits from the lower spark plug temp range.
I'm often surprised to see how much money is thrown into modification, without a balanced view point to tether the control factors relating to heat issues. Whilst it's great to come on a forum and say 'I've got a Milltek', or 'I'm running stage 2 spec', it's not so sexy to come on and say you are looking to spend some cash on cooling based on the increased boost pressures you're now running. Cooling per-say doesn't come with much of a label beyond a Forge FMIC, so carries very little kudos.
Lately you see people who's rolling road figures are some way below what they had hoped for, and I believe in some cases it is because all the effort is thrown at performance modifications rather than preventative control mods.
For those who have had the tenacity and bravery to stick with this 'war and peace' thread (and I apologize for the length of it now), I'd be really interested to hear your thoughts, experiences, and opinions on this subject. It's certainly a space which I believe is a quite neglected area of modification practice in the 'general public' sector of modifications.
For years there have been various products available for reducing underbonnet temperatures. Exhaust wraps, reflector blankets, firewall plates, high performance cooling system additives etc., and I wondered what else was available, and why these days no one seems to use this stuff to counter heatsoak. People spend small fortunes on twintercoolers or enhanced FMIC's, which although VERY worthy are actually on half of the story. The IC's only go some way to rectifying intake temps rather than resolving heat related issues at the root cause of the problem.
There is a site I've found, courtesy of a member on another forum, called: http://www.agriemach.com/
There are a range of products for wrapping exhausts, intake pipes, electrical protection, blankets etc...
Products that particularly caught my eye were:
1) Titanium exhaust wrap (link)
2) 4 cyl turbo insulating kit (link)
3) Pipe heat shield (link)
4) Reflect-a-gold pipe wrap tape (link)
5) Radiator relief cooling products (link)
It is widely accepted that heat not only robs engine power / efficiency, but excessive heat reduces the lifespan of underbonnet electrical and mechanical components. Whilst tolerances for this will be factored in to cars during the development phases of OEM testing, when the consumer decided to go for stage 1, 2, or 3 modifications there is a natural requirement to increase the capacity to cool things down.
What can I get for free?
There are some very basic 'for free' things you can do, which include careful driving during start up and warm down. Ragging your engine whilst cold (when the engine has not had time to circulate / thin the oil) is a major contributor to wear and damage. Less known is that by having a managed approach or 'cool down' regime, by running the car at much lower RPM for the last few minutes of your journey also helps tremendously. The oil can continue to run around the turbo as it cools meaning you get less coking of the oil in the turbo once it stops pumping (particularly if you car doesn't have a timed pump system). A high quality oil which is changed regularly will help to increase the life of your turbo. This heat up / cool down process will extend performance and longevity, but will not specifically reduce under bonnet temps.
Phenolic gaskets
Another product that seems to be recommended by serious enthusiasts, although it is something I would personally change unless the OEM product failed is a phenolic inlet manifold gasket. This heat insulated gasket stops the transfer of heat from the main block into the inlet manifold again reducing intake temps.
WMI
More recently we have seen the use in the UK of WMI (Water Methanol Injection systems), which inject a constant controlled flow of water/meths into the intercooler. These significantly increase the density of the intake air, and reduce the intake temps and the effects of detonation. Whilst a very useful mod, the only problem I see with this is that you have a supply side issue where you are having to constantly top up / purchase methanol. Whilst I see the benefit completely for track days or performance runs, unless you have a very large reserve tank it could become a burden over time for high mile daily drivers.
NOS
N20, or Nitrous Oxide causes a large drop in intake charge temperature, resulting in a denser charge, further allowing more air/fuel mixture to enter the cylinder. Nitrous oxide is sometimes injected into (or prior to) the intake manifold, whereas other systems directly inject right before the cylinder (direct port injection) to increase power. Personally, again as you are carrying tanks (which need refilling), it's not a route I'd go down (particularly as I run cars which are within a warrantable window). Street racers and Fast & Furious types will go giddy for it, but although its become a more progressive technology in recent years its still a bit of a one pop shot for my liking.
Cold Air Intakes
Various companies offer CAI's, and with the eagerly awaited Forge Twintake we will shortly be seeing another evolution of this product genre come to market. Getting a pure cold air intake feed under the bonnet is not easy, as the CAI itself will attract heat from the high underbonnet temps. If you run an open cone system with shrouding you will inevitably get some engine heat filtering back into the system. Getting good cold air fed to the filter from optimized vantage points (front fog vents), inner wing arches etc. can be useful (use good quality flexi hose - heat insulated), but beware of potential water ingress. Always recommended as the OEM systems are often restrictive, particularly now engine covers are used to house the air filter. As VAG cars don't have bonnet venting as standard you are always fighting the tide!
Lower temperature heat range spark plugs
Many tuners recommend running a spark plug which is one heat range below the OEM one when your car is heavily modified. I must admit I am not entirely sure what the outright benefit of this is, and can only assume that the detonation process with the richer fuel / air intake benefits from the lower spark plug temp range.
I'm often surprised to see how much money is thrown into modification, without a balanced view point to tether the control factors relating to heat issues. Whilst it's great to come on a forum and say 'I've got a Milltek', or 'I'm running stage 2 spec', it's not so sexy to come on and say you are looking to spend some cash on cooling based on the increased boost pressures you're now running. Cooling per-say doesn't come with much of a label beyond a Forge FMIC, so carries very little kudos.
Lately you see people who's rolling road figures are some way below what they had hoped for, and I believe in some cases it is because all the effort is thrown at performance modifications rather than preventative control mods.
For those who have had the tenacity and bravery to stick with this 'war and peace' thread (and I apologize for the length of it now), I'd be really interested to hear your thoughts, experiences, and opinions on this subject. It's certainly a space which I believe is a quite neglected area of modification practice in the 'general public' sector of modifications.
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