Discussion
www.pistonheads.com/sales/123262.htm
just in case any of you chaps are interested, these are for sale on this link, price is per pair.
just in case any of you chaps are interested, these are for sale on this link, price is per pair.
Ive had them on my 500 griff, and did 300 miles last sunday, and felt that the engine temps were lower, but ballistic banana has just bought some, and he will use a heat meter to do a before and after heat test to accurately see what heat is being deflected, so watch this space.
also now on e-bay.
http://cgi.ebay.co.uk/A-pair-of-Exhau
also now on e-bay.
http://cgi.ebay.co.uk/A-pair-of-Exhau
Edited by clive f on Wednesday 10th January 09:34
clive f said:
hi peter, bb is going to test the temperature of the heat shield in relation to the temperature of the exhaust behind it, to see how much protection the shield is offering to the fan belt and temperature sensors ect in that area.
I was referring to your comment about engine temperatures being lower (I think Steve mentioned this earlier in the thread, too). I'd expect a heat shield to be well worth while to protect components from heat and possibly reduce the intake charge temperature slightly, but I'd be surprised if it had any noticeable effect on the temperature of the engine itself.
If you're just comparing surface temperatures you'll see a huge difference because the exhaust manifold will run up to around 600C and the heat shield should be several hundred below that.
As you say Pete, I did mention it and I was also a little surprised to see the result during the testing as well. It was not something I was expecting.
I did some extensive temperature profiling before finalising on my design. This is where all the data came from in the PH press release. It provided a lot of insight. A good example is when I had a blowing exhaust manifold where it bolts onto the Y piece and the engine coolant temp immediately shot up into the 100+ mark. The fans switched in at low water temperatures. Something was heating the coolent. Coolant levels were fine and I eventually found an exhaust leak. The small leak from the Y piece joint was blowing onto the swirl tank and heating the water and otter switch up. Once fixed, the cooling problem went away. This made me think that the swirl pot could be susceptable and that the heat shield needed to be extended down to directly cover the otter switch etc and backwards to really isolate the components and that this was probably more important than protecting the fan belt.
I did some extensive temperature profiling before finalising on my design. This is where all the data came from in the PH press release. It provided a lot of insight. A good example is when I had a blowing exhaust manifold where it bolts onto the Y piece and the engine coolant temp immediately shot up into the 100+ mark. The fans switched in at low water temperatures. Something was heating the coolent. Coolant levels were fine and I eventually found an exhaust leak. The small leak from the Y piece joint was blowing onto the swirl tank and heating the water and otter switch up. Once fixed, the cooling problem went away. This made me think that the swirl pot could be susceptable and that the heat shield needed to be extended down to directly cover the otter switch etc and backwards to really isolate the components and that this was probably more important than protecting the fan belt.
your quite right in what you say steve,the swirl pot heat sensor does need to be protected, your shield appears to drop down flat in front of the exhaust, whereas mine is curved 
with the bottom edge stopping where the exhaust sits above the chassis rail,also protecting the swirl pot heat sensor at the same time as the fan belt.
with the bottom edge stopping where the exhaust sits above the chassis rail,also protecting the swirl pot heat sensor at the same time as the fan belt. Edited by clive f on Wednesday 10th January 13:17
shpub said:
As you say Pete, I did mention it and I was also a little surprised to see the result during the testing as well. It was not something I was expecting.
I did some extensive temperature profiling before finalising on my design. This is where all the data came from in the PH press release. It provided a lot of insight. A good example is when I had a blowing exhaust manifold where it bolts onto the Y piece and the engine coolant temp immediately shot up into the 100+ mark. The fans switched in at low water temperatures. Something was heating the coolent. Coolant levels were fine and I eventually found an exhaust leak. The small leak from the Y piece joint was blowing onto the swirl tank and heating the water and otter switch up. Once fixed, the cooling problem went away. This made me think that the swirl pot could be susceptable and that the heat shield needed to be extended down to directly cover the otter switch etc and backwards to really isolate the components and that this was probably more important than protecting the fan belt.
I did some extensive temperature profiling before finalising on my design. This is where all the data came from in the PH press release. It provided a lot of insight. A good example is when I had a blowing exhaust manifold where it bolts onto the Y piece and the engine coolant temp immediately shot up into the 100+ mark. The fans switched in at low water temperatures. Something was heating the coolent. Coolant levels were fine and I eventually found an exhaust leak. The small leak from the Y piece joint was blowing onto the swirl tank and heating the water and otter switch up. Once fixed, the cooling problem went away. This made me think that the swirl pot could be susceptable and that the heat shield needed to be extended down to directly cover the otter switch etc and backwards to really isolate the components and that this was probably more important than protecting the fan belt.
I don't doubt that you saw it, but I'm puzzled as to the cause. The most likely explanation I can think of is that the air leak was throwing the lambda reading out - if you're running a catted system. The amount of heat caused by a trace of exhaust gas puffing out of a leaking joint really is very small in the scheme of things and unlikely to cause any direct temperature change.
shpub said:
Personally think it is quite simple as It was blowing directly onto the base of the swirl pot pipe. The giveaway was a sudden desire to remove fingers from between the joint and bottom of the swirl pot before they became rather roasted... 
Fingers start burning at about 50C so it doesn't need much exhaust gas coming out at 300+ to feel seriously hot, I'm still not convinced that the amount of heat that will be transferred to the swirl pot from a blowing exhaust join is significant.
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