Aluminum Exhaust Manifold Comparrison?
03-30-2008, 01:07 AM
#22
Platinum Member
Platinum Member
Just something to think about.
If you have a seawater pump failure and the engine overheats - the exhaust has been run dry and I have seen the aluminum manifolds melt from being run dry.
I run Lightning headers and have burned the paint off mine from running dry. ( I run my headers almost dry on purpose to cut backpressure - I have dumps that spray the excess water on the top of my drives)
If you have a seawater pump failure and the engine overheats - the exhaust has been run dry and I have seen the aluminum manifolds melt from being run dry.
I run Lightning headers and have burned the paint off mine from running dry. ( I run my headers almost dry on purpose to cut backpressure - I have dumps that spray the excess water on the top of my drives)
Also have kept spare impellar kit on board as cheap as they are and easy to fix. Beats cutting a weekend short.
Jon
03-30-2008, 10:23 AM
#23
Geronimo36
Gold Member
03-30-2008, 10:25 AM
#24
Geronimo36
Gold Member
03-30-2008, 08:12 PM
#27
NO CIGIE - SS headers can be run dry they will get cherry red - If you begin to try that with aluminum you will have nothing but slag.
Have you ever tried to melt aluminum - I have - I made a nose cone for my Glastron Alpha drive before they were available aftermarket.
I tried to melt the aluminum in an iron skilet - I made a blast furnace and the pan melted before the aluminum did. I then realized that steal melts at a higher temp. I used a coffee can.
The aluminum WILL melt long before the SS will.
The SS headers don't like getting that hot but they won't melt.
Aluminum has a melting point of 1220* (My exhaust temp is at least 1350*) 316 Stainless Steal has a working temp of 2000* and a melting point of 2550*.
How often do you start the boat and drive it off the trailer and then beach it and leave the engines running while you park the trailer. ( My wife was still on the boat.) I came back 5 minutes later to see blue smoke coming out of the exhaust. KISS the rubber connectors good by.
Have you ever tried to melt aluminum - I have - I made a nose cone for my Glastron Alpha drive before they were available aftermarket.
I tried to melt the aluminum in an iron skilet - I made a blast furnace and the pan melted before the aluminum did. I then realized that steal melts at a higher temp. I used a coffee can.
The aluminum WILL melt long before the SS will.
The SS headers don't like getting that hot but they won't melt.
Aluminum has a melting point of 1220* (My exhaust temp is at least 1350*) 316 Stainless Steal has a working temp of 2000* and a melting point of 2550*.
How often do you start the boat and drive it off the trailer and then beach it and leave the engines running while you park the trailer. ( My wife was still on the boat.) I came back 5 minutes later to see blue smoke coming out of the exhaust. KISS the rubber connectors good by.
03-30-2008, 08:19 PM
#28
Panther - My engine was not damaged -- if you lost water flow at WOT it would be less than a minute before hot spots would be forming ( possible melt through ) on aluminum manifolds. Next to the header flange there isnt much water content and it would boil dry in a mater of seconds. and yes aluminum will transmit heat very well but not when it is 1/4 inch thick. If will hot spot.
03-30-2008, 10:03 PM
#29
Registered
I think the Dana Marine exhaust is top quality stuff too. I really like the seperate primary runners within the manifold and riser, but unless I read it wrong even Bobl admitted in his myth busting test column that Dana Marine claims (or had claimed) a 48hp increase by bolting on their manifolds----that's quite a claim, but they fell far short of that on Bob's test engine. Still a great exhaust system and I was very impressed that the Dana manifolds still held their own in comparision with the Lightning exhaust headers!
I currently have Stellings full length tubular headers now...I am blessed...14 years old/350 hours and still no leaks---only seen fresh water, but either way, if I was going to buy an exhaust manifold type of exhaust system it would be between the Stainless Marine or Dana.
Peace ya'll
03-31-2008, 04:44 AM
#30
Gold Member
Gold Member
Join Date: Mar 2003
Location: Grosse ile michigan
Posts: 2,374
Likes: 0
Received 92 Likes
on
36 Posts
I love being piled on, this way we can all brainstorm and learn from each other.....To my knowledge it has been provin more than once that dyno comparisons have been made on big cube blower motors....Stainless gen 111 have come out on top, not in every engine configuration but in most casses....As far as being a metalurgist i am not....But it sure does seem funney how they can give you a five year warrenty?????
Latstly i have gotten my manifolds so hot my hatches almost caught on fire, fried the whole motor, blistered all the paint off the manifolds and after a pressure test and a motor freshen my stainless marine manifolds are back in use....I am simply stating that for the money and the power i would never think of buying anything else,plus every time i tried to save a buck it bit me in the AS$....
Latstly i have gotten my manifolds so hot my hatches almost caught on fire, fried the whole motor, blistered all the paint off the manifolds and after a pressure test and a motor freshen my stainless marine manifolds are back in use....I am simply stating that for the money and the power i would never think of buying anything else,plus every time i tried to save a buck it bit me in the AS$....
