OK, lots to say on this, some of which may hurt. I'll try to keep it constructive. 1) the block will hold a lot of heat, but this is effectively managed (in normal operating conditions) through the cooling systems (oil and water). Yes, it has thermal mass, but we can't just 'do without it'... so its a necessary evil. 2) Heat wrap such as the kevlar bandage type, work, but issue is they cause parts to prematurely corrode. I really dont plan to have to replace rusted thru exhaust manifolds every 5 years... Its not going to work on a block (given), but can be ussed to shield other parts. radiant / conductive heat is always going to be there, so cannot effectively mitigate (unless you can completely seperate the turbo from the engine block, its not gonna happen). 3) they do use heat coatings. But for the price / average punter its not worth it. Surely you've seen every other post by Tech@EPR who coats everything in his weasel snot to help oil adherence / repelling and prevent heat through increased friction. 4) heat sinks... this made me crack up with how wrong it is. Heatsinks need airflow. There isnt much of that in an engine bay. If I have a heatsink with no airflow, whether I have a gram or a tonne of material, they will all be the same after a long period of heatsoak. I appreciate your out of the box thinking, but its all either A) wrong, or B) already been done.
As for the original question the most thermally conductive material listed there is aluminum, remember there are 2 sides to this equation I suggest you will be releasing more heat from the turbos than absorbing from the engine hence the use of intercoolers.
I appreciate you being constructive so I will try to reciprocate. 1) Yes - Internally it is controlled by water and oil and yes it is somewhat a necessary evil (unless you have ceramic piston blocks) but externally not so much as the large mass of radiating heat provides ambient heat radiation to other components that would otherwise be considerably cooler without it. The fact that many high end performance car manufacturers (such as Audi etc) are now including large heat shields around blocks in crucial areas somewhat testifies to the viability of doing this in thermal management engineering. Whether it is justifiable in a 300zx depends somewhat on application. 2. It is actually completely unjustifiable to say that your manifold will corrode away to completely nothing within five years because of heat wrap - I know this because I have previously had cars running for ten+ years with heat wrap around manifolds and when removed had no major signs of corrosion. Every-time you start it up any moisture is completely dried out and sure when you turn it off some moisture is absorbed and can effect iron components but the fact remains I - from experience never had any trouble after ten+ years! Seems like you have gotten information from either some bright spark blogs/ bloggers or perhaps someone out there stored there vehicle long term in damp conditions for five years and came back to find it rusted to the point it was completely destroyed and blamed it on heat wrap when it would have rusted out in those conditions in the first place. In addition there are some heat wraps that absorb less moisture than others and this can reduce it, so I find this argument somewhat hard to defend. Heat / thermal and ambient radiation only exists if you want it too - given the above statements - disconnecting turbo's to reduce ambient heat is not required. 3. As I said high end racing teams indulge in this in many different applications even including F1 etc - I would think there is some viability in this given there high end engineering skills and millions of dollars in research but accept that cost may be a factor, but you never stated this was a consideration at the beginning. 4. LOL :rofl:- You have actually cracked me up by saying that heat-sinks need airflow to be effective! The actual scientific facts are that heat-sinks are more effective with airflow but are actually still somewhat quite effective even without airflow by the simple fact they use the surface area to transmit the heat by radiation. Another fact is that there is actual airflow in under an engine bay even in the most cramped conditions - this has been conclusively proven in so many tests - that it is actually quite laughable as you would put it. Don't believe me on any of the facts stated here - go and ask a qualified engineer or do some more extensive research! Very small heat-sinks on high temp chips in consoles with no airflow at all are used for this reason! You stated the thermal abilities of metals in your first post but now your retracting it based on it being in a heatsink??? :rofl: Go and do some more research at the appropriate engineering sites before you disqualify the statement! I appreciate your constructive criticism but its either 1) wrong or 2) already been done in which case I should not have responded in the first place as I did not know, you were restricting the information to that what is UNKNOWN. I am now done with this post! :W:
The best way to eliminate heat soak with piping is keeping that enging bay vented and flowing as best as possible . coatings may help good airflow coming in but more importantly HOT airflow coming out , not too scientific .
Ahh dude? A heatsink is literally just a large surface area made into a compact shape. It cools in exactly the same way any flat surface cools, by transferring heat to the air around it. If there is no airflow, then the ambient air temp will rise to the same temperature as the heatsink. There is absolutely nothing special or amazing or incredibly technical about a heatsink, all it is is an increased surface area to allow more air to come into contact.
True - but a heat-sink can give you more surface area than what you could achieve by applying a flat piece of metal to a flat piece of metal. i.e. if you have 10cm square of metal available you can only apply 10cm square of metal in transferring heat radiation (we are forgetting air flow cooling here for a moment) but a heat sink can allow you to apply the same 10cm square base with up to 10+ times more conductive metal (in heat fins in a finned formation) to allow up to 10+ times more effective thermal heat radiation emissions. There is nothing technical about the simple science of increased area for thermal dissipation The original question is limited in response - as black beast points out - he will only be able to increase upon this by looking outside of the box! I am still done with this post and only responded given you were trying to be constructively critical - which I always appreciate I am not coming back here though - so fire away (the rest)
So shennanigans aside, I'm thinking my plan will be to go with a silicone accordion pipe replacement . From there alloy pipes should do the trick. This will be a good basis to work off if I wish to explore coatings down the track. I've got forward compatability this way. For those interested, I wont be finning my block, or creating a hybrid heatsink/turbo monstrosity. There is a reason air cooled engines died with the vw beetle. There is some interesting opinions around, but I guess that's science: suck it and see. For me, building a fast vehicle is more than just shopping for the most talked about parts and thumbing thru the performance catalogs, is more about innovation, engineering and lateral thought based on your individual application. So no hate when I disagree with what anyone says, I'm usually just of the opinion that it won't work for me... Unless of course you are an engineer, rocket scientist, or have first hand experience and opinions that I trust. Based on what a lot of people here claim to know, versus what comes across as a well researched wiki copypasta, I'm still to be convinced in a lot of cases. If I get around to any tests, I'll keep everyone posted.
+1 It's mentioned above: heat energy travels from hot to cold. If you reduce your ambient (i.e. engine bay) temps to below IAT. That way the hot intake air will dissipate heat TO the engine bay ambient air, instead of absorbing heat FROM the bay. But we all know zed bay gets pretty hot. Black beast is it hard to get the bay temps down a fair bit?
Water cooled inlet pipes & compressor housings would be a good addition to the complexities of a Z32 engine bay, oddly I was just chatting with someone about running a separate cooling system for the turbo core instead of using engine coolant that is up around 80 degrees c. This would reduce heat transfer to the compressor housing while off boost & reduce heat soak & transfer to the intercoolers & pipes etc, then when you stick your foot up it everything will be nice & cool(er)
I can see a lot of merit behind this actually. Youd need what, an oil cooler, small electric pump and associated hoses? Is there anyone else running a system like this? If not ill be happy to do back to back testing when i get round to putting in the new motor.
Edit: whoops, re-read mungyz post and realised he was talking more about the turbos water lines than cooling the piping Probably much more gain to be had just using water-to-air intercooling once you've already got the pump and radiator. I did some pretty rough calculations and got about 3 degrees increase in charge temp running through one metre of aluminium intake at 60 degrees. Compared to the drop in your intercooler that isn't much
I've never seen anyone doing it but that's not to say it hasn't been done. There could be related issues like the turbine housing getting significantly hotter than the core & repeated cycles could possibly cause bolts to come loose - maybe, not likely to be a real issue but just one thought of concern. You'd just need a pump of some sort & lines & a cooler, oil cooler of decent size would work as long as it was in good airflow, maybe put a fan on it. just need to consider power useage for the system compared to any potential gains. No point in spending 50watts to try and gain 5watts for a few seconds. A lot of earth moving equipment & trucks etc have water cooler turbine housings but I've not seen compressor housings water cooled though.
I think for most members here they would get a better return on investment just using a better intercooler...
The thread was about piping, right. The truck sites make references to cooling fins on piping, but a truck engine bay would have a lot more air flowing through it. Logically small improvements in other parts would probably get better results, the physics of all of this is that you are transferring the heat as quickly as possible to a location where you can apply a more effective cooling solution. If someone wants to say that heatsinks don't work in a tight engine bay, it is probably more correct to say heatsinks would be less effective in a tight engine bay if there is limited ability to extract the extra heat that would be released by the additional heat sinks. In electronics a heat sink might be used in unvented spaces because that component might overheat without it. Transferring that spot heat to increase the average heat in the unvented space is preferable if the other components are still within tolerances. In comparison the intake piping (all the piping) isn't likely to melt, is it? A bit of extra heat while the bulk of the heat is moved to another location for more effective cooling sounds OK.
Trucks also tend to run upwards of 30psi, that's a lot more heat in the charge piping so you get more energy dissipating through the fins
Most members yes. Or maybe no, are there more NAs on here than TTs? but people that are trying to push those extra kilowatts and winding up the boost would probably find sequential intercoolers give a bunch of insurance against rising temps
