Lurksalot Posted June 24, 2005 Share Posted June 24, 2005 Why do some builders wrap up their manifold pipes with the stuff Is it to hide rusty pipes or does it give some performance benefits any ideas ? Quote Link to comment Share on other sites More sharing options...
adhawkins Posted June 24, 2005 Share Posted June 24, 2005 I presume it's partly to keep the under-bonnet temperatures down... Andy Quote Link to comment Share on other sites More sharing options...
pistonbroke Posted June 24, 2005 Share Posted June 24, 2005 Yep purely thermal insulation , often used to stop the exhaust heat from melting / overheating other bodywork bits or engine parts that run close to the exhaust and cant be moved away eg. plug leads, starter motor cables, etc. Quote Link to comment Share on other sites More sharing options...
chappers Posted June 24, 2005 Share Posted June 24, 2005 Apparently, Powerspeed - the exhaust manufacturer in Kent, won't warranty any of their exhausts if the user is going to use exhaust wrap. Dave, from Powerspeed, recommends the use of e.g. heat resistant sheet to protect the vulnerable parts instead, or ceramic coat the exhaust. In a presentation he gave, it doesn't help if the wrap isn't wrapped tight enough because of air between the wrap and the exhaust, and so ceramic coating is better because there is no air between the coating and exhaust - don't ask why, its just what he said. Lagging the primaries also shifts the heat further down the system, so silencer packing might not last as long due to the increased temperatures - apparently! Quote Link to comment Share on other sites More sharing options...
Pembroke Pat Posted June 24, 2005 Share Posted June 24, 2005 surely trapped air is quite a good insulator of heat. It sounds like this chap wants you to spend more on ceramic coating rather than a cheaper option. Quote Link to comment Share on other sites More sharing options...
Blatman Posted June 24, 2005 Share Posted June 24, 2005 Ceranmic coating isn't much more expensive than exhaust wrap. And I don't think Powespeed do the ceramic coating themsleves, in which case there is no advantage to them by saying to get it done. Quote Link to comment Share on other sites More sharing options...
pistonbroke Posted June 24, 2005 Share Posted June 24, 2005 surely trapped air is quite a good insulator of heat. isnt that what he'se saying ? the trapped in heat can't radiate through the air/bandage so it must be contained in the system till it gets lower down the pipe i.e. hotter temp in the silencer Quote Link to comment Share on other sites More sharing options...
chappers Posted June 24, 2005 Share Posted June 24, 2005 Your right blatters, Powerspeed do not do ceramic coating. Apparently, the reason they don't warranty their exhausts if you use wrap is because they have had certain instances where the primaries have become so hot due to the wrap that they have effectively softened inside that wrap and sagged, not helping exhaust performance. Powerspeed gave a presentation at a kentkitcarclub meeting, and Dave from Powerspeed even apologised to Neil foreman (of nfauto.com) for saying don't use exhaust wrap, knowing full well that Neil sold it. I was contemplating using some wrap myself, not that I need to shield any engine parts from heat, but the theory of reduced engine temperatures causing denser air to go into the intake and thus get more power seemed feasible to me, but I have decided against it. Would a bonnet vent instead give any noticeable power gain? Dave did admit though, that there are certain situations where it is unavoidable for exhaust wrap not to be used, because it is the only way to avoid other problems. Kev. Quote Link to comment Share on other sites More sharing options...
Lurksalot Posted June 24, 2005 Author Share Posted June 24, 2005 Dave did admit though, that there are certain situations where it is unavoidable for exhaust wrap not to be used, because it is the only way to avoid other problems. Kev. chappers what might these problems be Quote Link to comment Share on other sites More sharing options...
Boomy Posted June 24, 2005 Share Posted June 24, 2005 Mine is also wrapped in this stuff, web pages suggest it stops up to 80% of heat escaping, is that really true? As it is now my feet feel like they are on fire when i drive about so i'm also not sure if i should remove it or maybe add bonnet vents. It sure do get toasty under there! Quote Link to comment Share on other sites More sharing options...
Lurksalot Posted June 24, 2005 Author Share Posted June 24, 2005 Boomy That was to be my next thread I was given a ride in a prospective purchase and the transmission tunnel felt like it was ready to fry the sausages Do I assume this is normal Quote Link to comment Share on other sites More sharing options...
Boomy Posted June 24, 2005 Share Posted June 24, 2005 Boomy That was to be my next thread I was given a ride in a prospective purchase and the transmission tunnel felt like it was ready to fry the sausages Do I assume this is normal Well mine is only a 1700ish X flow vulcan jobby yet even the gearstick gets quite warm as do the bits you mention. I also have quite a large opening by the pedals so no doubt plenty of engine heat flows in that way. The car has been fine pretty much in temp terms with it only creeping up to 100 on the temp gauge once.That was a few days ago on one of these very warm days but wasn't while sitting in traffic etc though. I also noticed it was down to the minimum mark when i got home in the water bottle, so i either have a small leak (this is possible as the last owner did mention it) or something else is going wrong. Normaly it sits around the 70/80 mark and i flick the fan on if stuck in traffic and it has been fine.So maybe due to outside temps and a small water leak it was enough to make it get extra toasty on that day! But either way, it does get very warm yes.I hope that is normal aswell now Quote Link to comment Share on other sites More sharing options...
Blatman Posted June 27, 2005 Share Posted June 27, 2005 Do I assume this is normal Yup. The tunnel and footwell will get pretty hot. Mostly because when you're on the move all that hot air is being blown backwards to the footwells and down the transmission tunnel... FWIW, my sprint car has wrapped exhausts to try to reduce underbonnet temps. I am sceptical about increased power benefits, but saving the alternator from frying is a worthwhile enterprise. My exhausts aren't sagging. To sag, they'd have to get beyond red hot, which they just won't do during normal running. Unless the exhausts are made from thin wall tubing or aren't particularly well supported, I can't see why they should sag. A bonnet vent just to let hot air out won't find you any more horsepower I wouldn't have thought. So, IMHO, use the exhaust wrap if it provides a benefit to you... Quote Link to comment Share on other sites More sharing options...
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