Twiss 0 Posted May 18, 2007 Hello I've gone through the search and have found lots of intresting bits of info but I haven't found yet any thing about what the OEM manifold is made from. As I was thinking of heat wraping it so to keep the gases hotter for longer. But only if this would help the performance. Thanks Vaughn Quote Share this post Link to post Share on other sites
Shaggy 0 Posted May 18, 2007 I believe its made of cast iron. Quote Share this post Link to post Share on other sites
bananawhip 0 Posted May 18, 2007 ha, It's amazing what us Valver boys will do to squeeze out a touch more power isn't it. I was thinking about it myself so let us know how you get on. Quote Share this post Link to post Share on other sites
Twiss 0 Posted May 21, 2007 after some more searching the web this idea seems to have mixed thoughts about the benifets to a cast iron manifold. and also that the chances that the cast iron manifold would crack increases. Any one else get some info or idea/opinion? Quote Share this post Link to post Share on other sites
davidwort 0 Posted May 21, 2007 cream-cheese, no sorry, it's cast iron as said, just in one of those moods today. it's perfectly good as it is, even with a modified head all you really need to do is internally polish/remove casting marks. For the ultimate top end on a valver an all-in-one downpipe and mainfold may get you a few more horses, but for everyday noise, torque, reliability and fitment the OEM manifold and dowpipe is fine. IIRC heat wrap is only needed on a tubular steel manifold/downpipe, the cast iron ones are fine as they are. Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted May 21, 2007 Aye, no need to wrap iron as it retains plenty of heat naturally. Wrapping is only necessary on metal that loses heat too quickly, such as thin steel tubing. It all helps with scavenging, but that's only critical on norm asp' engines. I wouldn't worry about wrapping iron causing cracking.....cast iron does that itself without any assistance! Iron just needs room to expand and contract. I've seen many manifolds with exact bore stud holes, the manny gets hot, can't expand or contract around the stud holes and cracks. Quote Share this post Link to post Share on other sites