Keep OEM exhaust valves? or go with inconel super alloy?
Mar 9, 2014, 09:42 PM
#1
Keep OEM exhaust valves? or go with inconel super alloy?
So I have my cylinder head off and tested it for valve leaks. ....and they leak... 
The exhaust valves are much worse than the intake valves. Engine has 56K miles on it.
I am wondering if I should just have a valve job done and reuse the OEM sodium filled exhaust valves or if I should go for some inconel exhaust valves?
I'll probably stay with OEM intake valves.
I hear that Ferrea makes the best valves, but what about Supertech?
The exhaust valves are much worse than the intake valves. Engine has 56K miles on it.
I am wondering if I should just have a valve job done and reuse the OEM sodium filled exhaust valves or if I should go for some inconel exhaust valves?
I'll probably stay with OEM intake valves.
I hear that Ferrea makes the best valves, but what about Supertech?
Mar 10, 2014, 02:22 PM
#2
OK, since I am on a budget I decided I am going to keep OEM intake valves and go with Supertech inconel exhaust valves and Supertech viton stem seals.
I am having Port Flow Design in Harbor City, CA do the valve job. Looks and sounds like he knows what he is doing and definitely has the right equiptment.
I am having Port Flow Design in Harbor City, CA do the valve job. Looks and sounds like he knows what he is doing and definitely has the right equiptment.
Mar 10, 2014, 03:28 PM
#3
stock exhaust valve is better. it would be a 35 dollar valve aftermarket. its a filled valve so it stays cooler. and its also very light. the inconel valve sounds cool but its a step backwards
the mitsu intake valve is nothing special. same valve was used for 20 years. doesnt need anything special as its bathed in fuel and it runs cool.
the mitsu intake valve is nothing special. same valve was used for 20 years. doesnt need anything special as its bathed in fuel and it runs cool.
Mar 10, 2014, 04:01 PM
#4
stock exhaust valve is better. it would be a 35 dollar valve aftermarket. its a filled valve so it stays cooler. and its also very light. the inconel valve sounds cool but its a step backwards
the mitsu intake valve is nothing special. same valve was used for 20 years. doesn't need anything special as its bathed in fuel and it runs cool.
the mitsu intake valve is nothing special. same valve was used for 20 years. doesn't need anything special as its bathed in fuel and it runs cool.
Sodium filled are indeed very good at transferring heat from the head of the valve to the stem, and then to the guide and into the head by the liquid sodium moving up and down inside from the head to the stem. Sodium filled does a better job than inconel at transferring heat for applications where EGT's are reasonable and do no surpass a certain point, as in stock applications. But in higher power, higher EGT applications, inconel or super alloy becomes necessary.
I also read this in an online article:
Inconel and Sodium-Filled Valves
A blend that Ferrea uses on both the intake and exhaust side is IN751, which is an inconel material. Used in an engine that sees high heat on the intake side, this material will hold its memory and integrity quite well and is rather flexible. The term “memory” refers to the valve’s ability to shift and move in different positions under extreme loads without encountering fatigue issues.
“Inconel in this day and age is used a lo in our industry; almost as much as titanium. Inconel was brought on by the avionics industry and has made it’s way to the racing, as may things do. Inconel is categorized under our Super Alloys, but we actually create our own blends to that make it handle high temperatures that much better. so instead of handling in the neighborhood of 1,800 degrees, we’re looking at about 2,400 degrees.
Ferrea also manufactures sodium-filled valves, albeit on their OEM side where these valves are primarily limited to. Sodium bases used in these valves are only tested to around 1,600 degrees, which most racing and high performance engines exceed. The liquid sodium travels up and down the stem of the valve, and at the boiling point, the liquid turns to gas. You then essentially have a valve with a hollow neck and excessively high temperatures, the chance of failure is very high.
However, the benefit of the sodium-filled valve comes in the form of added longevity due to the cooling properties of the sodium, and in street cars where temperatures are kept in check and hundreds of thousands of miles are expected, these are key.
Mar 10, 2014, 04:16 PM
#5
Thinking i would be more concerned with how this happened in 56k-- sounds like you are somehow generation either a lot of heat in the cylinder, IE running lean or you had a poor valve job done earlier? Was that head rebuilt, hence the statement the motor has 56k, not the car has 56K?
Mar 10, 2014, 04:25 PM
#6
Thinking i would be more concerned with how this happened in 56k-- sounds like you are somehow generation either a lot of heat in the cylinder, IE running lean or you had a poor valve job done earlier? Was that head rebuilt, hence the statement the motor has 56k, not the car has 56K?
I have tuned the car myself since and I know that I do not run it lean. The car still made great power despite the leaking valves and lower compression... I wonder what it would have been like with no leaks...
Mar 10, 2014, 09:21 PM
#7
Interesting... I have spoken with Ferrea and Supertech and Port Flow Design and they all recommend inconel or super alloy. It can handle higher EGT's than sodium filled, plus they are solid which is stronger than hollow sodium filled. The boiling point of sodium is 1621°F, when you get there obviously it turns from liquid to gas and the heat transfer becomes very bad.
Sodium filled are indeed very good at transferring heat from the head of the valve to the stem, and then to the guide and into the head by the liquid sodium moving up and down inside from the head to the stem. Sodium filled does a better job than inconel at transferring heat for applications where EGT's are reasonable and do no surpass a certain point, as in stock applications. But in higher power, higher EGT applications, inconel or super alloy becomes necessary.
I also read this in an online article:
Inconel and Sodium-Filled Valves
A blend that Ferrea uses on both the intake and exhaust side is IN751, which is an inconel material. Used in an engine that sees high heat on the intake side, this material will hold its memory and integrity quite well and is rather flexible. The term “memory” refers to the valve’s ability to shift and move in different positions under extreme loads without encountering fatigue issues.
“Inconel in this day and age is used a lo in our industry; almost as much as titanium. Inconel was brought on by the avionics industry and has made it’s way to the racing, as may things do. Inconel is categorized under our Super Alloys, but we actually create our own blends to that make it handle high temperatures that much better. so instead of handling in the neighborhood of 1,800 degrees, we’re looking at about 2,400 degrees.
Ferrea also manufactures sodium-filled valves, albeit on their OEM side where these valves are primarily limited to. Sodium bases used in these valves are only tested to around 1,600 degrees, which most racing and high performance engines exceed. The liquid sodium travels up and down the stem of the valve, and at the boiling point, the liquid turns to gas. You then essentially have a valve with a hollow neck and excessively high temperatures, the chance of failure is very high.
However, the benefit of the sodium-filled valve comes in the form of added longevity due to the cooling properties of the sodium, and in street cars where temperatures are kept in check and hundreds of thousands of miles are expected, these are key.
Sodium filled are indeed very good at transferring heat from the head of the valve to the stem, and then to the guide and into the head by the liquid sodium moving up and down inside from the head to the stem. Sodium filled does a better job than inconel at transferring heat for applications where EGT's are reasonable and do no surpass a certain point, as in stock applications. But in higher power, higher EGT applications, inconel or super alloy becomes necessary.
I also read this in an online article:
Inconel and Sodium-Filled Valves
A blend that Ferrea uses on both the intake and exhaust side is IN751, which is an inconel material. Used in an engine that sees high heat on the intake side, this material will hold its memory and integrity quite well and is rather flexible. The term “memory” refers to the valve’s ability to shift and move in different positions under extreme loads without encountering fatigue issues.
“Inconel in this day and age is used a lo in our industry; almost as much as titanium. Inconel was brought on by the avionics industry and has made it’s way to the racing, as may things do. Inconel is categorized under our Super Alloys, but we actually create our own blends to that make it handle high temperatures that much better. so instead of handling in the neighborhood of 1,800 degrees, we’re looking at about 2,400 degrees.
Ferrea also manufactures sodium-filled valves, albeit on their OEM side where these valves are primarily limited to. Sodium bases used in these valves are only tested to around 1,600 degrees, which most racing and high performance engines exceed. The liquid sodium travels up and down the stem of the valve, and at the boiling point, the liquid turns to gas. You then essentially have a valve with a hollow neck and excessively high temperatures, the chance of failure is very high.
However, the benefit of the sodium-filled valve comes in the form of added longevity due to the cooling properties of the sodium, and in street cars where temperatures are kept in check and hundreds of thousands of miles are expected, these are key.
Last edited by 94AWDcoupe; Mar 10, 2014 at 09:24 PM.
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Mar 11, 2014, 06:39 AM
#8
OK, since I am on a budget I decided I am going to keep OEM intake valves and go with Supertech inconel exhaust valves and Supertech viton stem seals.
I am having Port Flow Design in Harbor City, CA do the valve job. Looks and sounds like he knows what he is doing and definitely has the right equiptment.
I am having Port Flow Design in Harbor City, CA do the valve job. Looks and sounds like he knows what he is doing and definitely has the right equiptment.
Tom will take care of you @ portflow. They have some of the best equipment on the market.
Have him work his magic!
Mar 11, 2014, 06:10 PM
#9
I thought Supertech were going to make Inconel valves filled with sodium. When you spoke with Supertech, did they mention this to you?
http://blog.motovicity.com/?p=1470
http://blog.motovicity.com/?p=1470
Mar 11, 2014, 08:39 PM
#11
I thought Supertech were going to make Inconel valves filled with sodium. When you spoke with Supertech, did they mention this to you?
http://blog.motovicity.com/?p=1470
http://blog.motovicity.com/?p=1470
Mar 11, 2014, 08:42 PM
#12
I also got pricing on the Ferrea super alloy competition plus exhaust valves from realstreetperformance.com for $199 for the set.
I wanted to give Tom my business though, he is a great guy and he only sells supertech.
Mar 12, 2014, 08:04 AM
#13
I'm not sure where you saw that price, but you are way off. Tom at Port Flow Design is getting them for me at $25 per valve, so $200 for all the exhaust valves.
I also got pricing on the Ferrea super alloy competition plus exhaust valves from realstreetperformance.com for $199 for the set.
I wanted to give Tom my business though, he is a great guy and he only sells supertech.
I also got pricing on the Ferrea super alloy competition plus exhaust valves from realstreetperformance.com for $199 for the set.
I wanted to give Tom my business though, he is a great guy and he only sells supertech.
Mar 12, 2014, 09:03 AM
#14
the 56 was suggested retail for the sodium filled valve from supertech. its in the article that was posted. so I am not way off. just because someone sells valves for a living doesnt make their advice correct. do you really think they are going to send you to mitsubishi for valves when they can sell you theirs? sometimes I wonder why people even come to forums for advice when they just ignore it.. how is it you buy "sodium filled valve" would be the ultimate when you hear it from supertech, but ignore it when it comes from mitsubishi who cant speak? like I said. you are taking a step backwards in valve design. plain and simple.
Anyways, I have now read that article and it backs up everything I have read in my research...
"For general purpose, high performance and street engines up to 280-horsepower, Supertech’s solid forged Stainless Steel valves typically fill the bill. As you increase output or add on forced induction or nitrous, it’s time for sodium valves to better manage heat dissipation.
“If you’re hitting 120-180 hp/liter, then a solid Inconel is a good match. If you’re above this number of 180hp/liter (1,000 hp), then sodium-filled Inconel is recommended,” Tagliavini said. “That is important because excessive heat causes warpage, which leads to improper seating, then more heat problems.”"
If I was going by those numbers above, I should technically have the sodium filled inconel, since I will be higher than 180hp/liter... but supertech told me that I didn't need it.
And yes, just because someone sells valvetrain components for a living doesn't mean for certain their advice is correct. I always take advice with a grain of salt especially when getting it from someone that sells what they are giving advice on. I am doing thorough research on it... hence why I have called multiple people to see if i get the same advice everywhere as well as posting on this forum and searching the internet. So far the consensus is for inconel everywhere except for you 94awd.
You can't argue the fact that inconel exhaust valves are used in high performance racing applications over sodium filled stainless. Take top fuel dragsters for example, they use inconel: http://www.carcraft.com/techarticles...p_fuel_engine/
Why aren't they using sodium filled stainless?
You can't say i'm going backwards and that sodium filled hold up to heat better than inconel, that's just wrong. You are entitled to your opinion that inconel is overkill and not necessary for my application, and you may be right... But for me $200 is cheap insurance.
I am not ignoring your advice, I am taking it right along with everything else and making my decision based on what I feel is right with all the info I have.
Also, I dropped off my head last night to Port Flow Design. Tom took out an exhaust valve and measured the runout and said it is a little warped. We didn't see carbon deposits on the valve seat area on the seat or the valve that would be causing the leak, so it is likely the warpage that was causing the leak...
Last edited by TurboTylerIX; Mar 12, 2014 at 09:06 AM.
Mar 12, 2014, 10:42 AM
#15
You can't argue the fact that inconel exhaust valves are used in high performance racing applications over sodium filled stainless. Take top fuel dragsters for example, they use inconel: http://www.carcraft.com/techarticles...p_fuel_engine/
Why aren't they using sodium filled stainless?
You can't say i'm going backwards and that sodium filled hold up to heat better than inconel, that's just wrong. You are entitled to your opinion that inconel is overkill and not necessary for my application, and you may be right... But for me $200 is cheap insurance.
Why aren't they using sodium filled stainless?
You can't say i'm going backwards and that sodium filled hold up to heat better than inconel, that's just wrong. You are entitled to your opinion that inconel is overkill and not necessary for my application, and you may be right... But for me $200 is cheap insurance.
the inconel valve you are buying into is a solid valve. so its substantially heavier. this is a step backwards. making the springs weaker. or requiring heavier springs which cost hp and create heat. sodium valve runs cooler it last longer before a valve job is needed. sodium filled valve runs cooler so detonation threshold in the combustion chamber is lowered. the only advantage of inconel is it can handle more heat before failing. but since running a 4g63 at even 900hp you will be no near failure thresh holds due to heat there is no reason to use inconel. inconel doesnt handle daily heat as well as a cooler running sodium filled valve. its not an upgrade.
you are wrong again and I give up trying to help you.