The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support RTM Racing
Please Support ExtremePSI

Tubular manifold?

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

screwdgie

20+ Year Contributor
254
4
Apr 6, 2003
Barrington, Illinois
I am considering getting a tubular exhaust manifold for my car. I'm still on the 14b right now and may step up to a 16g at some point after I max out my 14b. My question is, will a tubular manifold help me at all on the 14b? How about the 16g? Any recommendations on brands?
 
I'm sure it will help some with spool, but it will be good to have when upgrading in the future you won't have to replace it as long as you stay using mitsu flanged turbos. I recommend punishment racing, they have nothing, but positive feed back and a life time warranty. Not to mention their parts look AMAZING!
 
It'll look badass for a couple weeks till it starts turning ugly brownish colors after a few heat cycles.
 
I don't think its oxidation. The heat from the exhaust is what is doing the color change. You have to remember that those EGTs comming out of the head can reach 1900 degrees depending on your state of tune. As for the other question about the exhaust note, yes it will change. My SBR changed the tone of my car and my new manifold did again too. The sound, people have told me, is somewhat like a very powerful all-motor Honda. The exhaust pulses in an equal length manifold really let you hear the engine and they change with the diameter of the runners used too.
 
I like the new one much better. If you've ever heard an Evo with a Shearer style manifold, it sounds just like that. It's very loud when the boost comes on even when the wastegate is still closed. I'm from Mundelein.
 
My question is why spend the money on somthing that doesnt need to be changed?

If anything get a 2g or evo3 exhuast manifold. Wont crack like a tubular will and will flow more than you will ever need.

Darryl hudson went mid 9's on a port 2g manifold.
 
Hey, how about I defend this "your tubular manifold will crack" for the 10000000th time. THEY DO NOT CRACK ALL THE TIME!!!!! If you buy a cheep one without support for the turbo or one that has bad welds then yes it might crack. Spend some money and buy a quality one that has been proven on more cars than one race car like the Shearer. Please stop telling people that they don't need to upgrade too. Just because one or two guys can do something doesn't mean the rest of us can. This doesn't apply to just the manifold either. One setup might work for someone and not for another like "why upgrade past a 14b? Someone went 11s on it." Doesn't mean everyone else can or wants to.
 
For those who don't think a tubular is worth the extra cost, stick to the 2g/Evo manifolds. They will flow fine for any hp goal, no question. For those who want better spool, that's where a tubular will help. If they didn't help in some regard all the big racing programs would just stick to factory cast/ported manifolds ;) Nobody's saying a 2g/Evo cast manifold isn't sufficient for hp goals, they're just not the best piece available.

FYI, I've had my DNP header for 2 years now and have taken the car racing many times. No cracks. The idea that tubular headers always crack is a myth. They're only slightly more prone to cracking than a cast manifold because they are welded. Get a good one and you won't have to worry.
 
I don't think its oxidation. The heat from the exhaust is what is doing the color change. You have to remember that those EGTs comming out of the head can reach 1900 degrees depending on your state of tune. As for the other question about the exhaust note, yes it will change. My SBR changed the tone of my car and my new manifold did again too. The sound, people have told me, is somewhat like a very powerful all-motor Honda. The exhaust pulses in an equal length manifold really let you hear the engine and they change with the diameter of the runners used too.


What do you think it is then? DIRT? Dude, it's oxidizing due to the heat, and abundance of air and moisture in your engine bay. Heat accelerates oxidation.

And I'm sorry, but cracking in a tubular is inevitable. The welds are weaker than the stainless no matter how you look at it. Chemistry is chemistry. Some may last longer than others, but eventually they will all crack through constant heat cycling.
 
For those who don't think a tubular is worth the extra cost, stick to the 2g/Evo manifolds. They will flow fine for any hp goal, no question. For those who want better spool, that's where a tubular will help. If they didn't help in some regard all the big racing programs would just stick to factory cast/ported manifolds ;) Nobody's saying a 2g/Evo cast manifold isn't sufficient for hp goals, they're just not the best piece available.

FYI, I've had my DNP header for 2 years now and have taken the car racing many times. No cracks. The idea that tubular headers always crack is a myth. They're only slightly more prone to cracking than a cast manifold because they are welded. Get a good one and you won't have to worry.

I understand this, its just most of the time people want a tubular manifold they do not buy a quility product beacuse they are expensive. And as for decrease spool time, how much are you going to gain in spool time on a 16g or a 14b, my guess is what 200-300rpm. Thats not alot for a turbo that already spools fast.

To me when the 2g mani can go mid 9's with no problem then what is the big deal? People go with them most of the time becuase they are running large turbos that spool time is greatly effected by a tubular or they do not use a dsm housing. With that being said, how do you suggest its a good idea for the person in question with a 14b and wants to upgrade to a 16g that already has a 2g mani on the car, that a tubular manifold is a worthwhile upgrade? That is my question. For him its not worth it. in my opinion
 
I understand this, its just most of the time people want a tubular manifold they do not buy a quility product beacuse they are expensive. And as for decrease spool time, how much are you going to gain in spool time on a 16g or a 14b, my guess is what 200-300rpm. Thats not alot for a turbo that already spools fast.

To me when the 2g mani can go mid 9's with no problem then what is the big deal? People go with them most of the time becuase they are running large turbos that spool time is greatly effected by a tubular or they do not use a dsm housing. With that being said, how do you suggest its a good idea for the person in question with a 14b and wants to upgrade to a 16g that already has a 2g mani on the car, that a tubular manifold is a worthwhile upgrade? That is my question. For him its not worth it. in my opinion
Most people in the DSM world don't have a lot of money to spend so they'll suggest not getting something like a tubular header. It's not worth the money to them. For some though, they want the best part they can get and 200-300 rpm on a 14b or 16g is worth the extra cost, especially if there is any chance of upgrading to a larger turbo later. You can't just make the assumption that his budget and goals are the same as yours.

The idea here isn't to be the guy's financial planner and make decisions for him on how to spend his money. It's to let the guy know that there IS something to gain by going with a tubular header. Whether or not it's worth it is for HIM to decide based on his budget and his goals. Since he hasn't specified his goals for the car or the type of driving he'll be doing I can't see how anyone here would be able to begin to decide whether it's worth it or not in HIS case.

The answer to his original question:

Yes, a tubular header should help on a 14b, though not as much as it would on a larger turbo. It will not help much in terms of direct hp gains but it will help get you maximum flow for better spool and throttle response due to the design of the runners compared to the factory manifolds our cars come with. Whether it's worth the money is completely up to you. There are other upgrades you can do that will improve your setup more, but if you want to optimize every part of your system, this is an option. And yes, the tubular header may crack at the welds, but as I said before, cast manifolds crack too. I wouldn't allow that to be the deciding factor. If you want your car to be as maintenance-free as possible don't mod it and don't drive it hard. Breaking parts is just part of the hobby. Get used to it.
 
I have the SFP Manifold on mine with my 50 trim.

Go get some VHT 2000 degree paint and paint it silver and it looks beautiful. Been on the car like that for 3 years. No cracks, no discoloration, and no paint ever chipped off. Daily driven and also at the track.

Erik
 
Chris, just wondering what your thoughts are relative to this, specifically Luke's post #22 and my post #25.
http://www.dsmtuners.com/forums/showthread.php?t=255307

Since that thread I have done a little more research and the picture I am coming up with is that the smaller interior volume of a stock manifold should be more conducive to quicker spool and responsiveness while the larger volume of a tubular manifold will benefit in the higher rpm range where the total volume of exhaust gases and the subsequent backpressure becomes more of a factor. I can't cite a reference for you regarding this as I have pulled bits and pieces of info from various sources, none of them wording the issue plainly like that but (unless I am misinterpreting) that is what I have come away with.

I'm not arguing the benefits of one over the other (they both have pros and cons) but just trying to have a better understanding.

So the benefits of a tubular manifold aside, did you notice any downside after switching from a stock cast manifold?
 
Chris, just wondering what your thoughts are relative to this, specifically Luke's post #22 and my post #25.
http://www.dsmtuners.com/forums/showthread.php?t=255307

Since that thread I have done a little more research and the picture I am coming up with is that the smaller interior volume of a stock manifold should be more conducive to quicker spool and responsiveness while the larger volume of a tubular manifold will benefit in the higher rpm range where the total volume of exhaust gases and the subsequent backpressure becomes more of a factor. I can't cite a reference for you regarding this as I have pulled bits and pieces of info from various sources, none of them wording the issue plainly like that but (unless I am misinterpreting) that is what I have come away with.

I'm not arguing the benefits of one over the other (they both have pros and cons) but just trying to have a better understanding.

So the benefits of a tubular manifold aside, did you notice any downside after switching from a stock cast manifold?
That theory sounds good enough, but it would have to be tested. My belief that a sharp 90* bend in a manifold runner is not as good as a gradual transition is also just a theory. You see tubular manifolds used widely in racing which is where I get a lot of my ideas.

The difficult part of all of this is that DSMs are not widely raced these days by race teams who have multiple engineers who would make decisions that would tell us a lot more about how things could be done for certain applications. All we have to go by are a few people having success here and there and the manufacturers. The pool of knowledge isn't as big as it is with other cars, so sometimes you have to look at other cars and see what they're doing - and that isn't ideal either. So we'll continue to have lots of theories floating around about a lot of things. And though some theories might be tested the results won't necessarily apply to every car and every situation.
 
That theory sounds good enough, but it would have to be tested. My belief that a sharp 90* bend in a manifold runner is not as good as a gradual transition is also just a theory. You see tubular manifolds used widely in racing which is where I get a lot of my ideas.

The difficult part of all of this is that DSMs are not widely raced these days by race teams who have multiple engineers who would make decisions that would tell us a lot more about how things could be done for certain applications. All we have to go by are a few people having success here and there and the manufacturers. The pool of knowledge isn't as big as it is with other cars, so sometimes you have to look at other cars and see what they're doing - and that isn't ideal either. So we'll continue to have lots of theories floating around about a lot of things. And though some theories might be tested the results won't necessarily apply to every car and every situation.

Some very valid points. Thanks for the reply.:)
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top