Divided manifold vs not

kjpcummins said:
The reason I moved my turbo had nothing to do with the exhaust side. I built the equal length header simply because I had to build something to get the exhaust to the turbo. The reason I moved my turbo is completely different than the reason you moved yours so I was curious.
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How do you know?
 
How about stop pissing at each other's shoes and post data?

I'm trying to find what I had saved. Western Digital hard drives are not trust worthy. It seems like some info was shed in the thread on or around LoveFabs manifold.

Sent from my XT1575 using Tapatalk
 
kjpcummins said:
Your more than welcome to go pay for your own like everyone else has to.
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I'm not trying to be an a**hole. I understand people have spent time and money developing their own setups. I just assumed, especially if we're not in direct competition, that this community likes to help each other out and progress. :Cheer:
If you don't want to share, that's totally fine.

97crewcab said:
Our current manifold puts the turbo out front so it isn't a simple swap. It still may happen this year of we feel the need to try.

I have heard the discussion both ways. One says divided makes more power, the other says as long as the manifold isn't a restriction, it won't matter. This is in a pulling application only, not street or drag racing. As with anything, I would rather get the details myself.
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I just meant, if you were swapping to a Steed to begin with, maybe someone would lend a similarly spec'd, non-divided, Steed for the Hell of it. If I were in a situation like that, I'd probably pay the $75 for a second set of runs and spend the 20-30min to swap an exhaust manifold for the gained knowledge.

Also, I really like your current manifold. Looks extremely simple and robust, and well made!

Redrider2911 said:
The turbo spools up by a volume of air being forced into the volute, through the small opening at the end and across the turbine at a high velocity. correct? With as long of a volute the turbo has, would it be wrong to suggest that the exhaust manifold more simply acts like a pressure holding tank feeding the turbo volute and that any turbulence in the manifold does not effect the velocity at which the hot air moves across the turbine?

I can see manifold design being very important in a N/A application where you want the exhaust scavenged as quickly as possible between strokes, but when we put a huge restriction right at the manifold wouldn't all that change?
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I see what you're saying, but I don't think that's the case. There's definitely performance to be had just from switching from the OEM T3 to a decent aftermarket T3. I don't think they're just a constant pressure source. The pulsing does a lot for sure. What I don't understand is why a divided would necessarily change things especially when two cylinders are firing from both sides at the same time.
I do agree with you on the cylinder scavenging for NA exhausts though. I do think it's far more important that this application.
 
CorneliusRox said:
I just meant, if you were swapping to a Steed to begin with, maybe someone would lend a similarly spec'd, non-divided, Steed for the Hell of it. If I were in a situation like that, I'd probably pay the $75 for a second set of runs and spend the 20-30min to swap an exhaust manifold for the gained knowledge.

Also, I really like your current manifold. Looks extremely simple and robust, and well made!
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I thought maybe you were joking on your comment since I said I had a steed on the shelf that I used to run.
If our current manifold was an easy swap to the steed, I would have tried it on back to back days during some of our 2 day events. Every year we say we are going to dyno, but we never do. Maybe this year....LOL

This discussion is a lot like aftermarket intake manifolds for cummins. There are 10 different flavors of those, but does one make any more power than another? Does a runner intake make any more power than a side draft? I doubt many have spent the time and money to try more than 2-3 of them. If you have, I doubt you will be posting here telling everyone which one is best.
 
I know that this thread is now over 3 months old, but I thought I would check back in. This last weekend I had my turbos and exhaust manifold off to replace some blown manifold gaskets. While I had everything apart I went ahead and welded a piece of 3/16" flat to divide the manifold down the center of my T3 flange, leaving about a 3/16" space between the end of the divider and the turbo flange to allow pressure to equalize when the internal wastegate opens. Immediately I noticed that my off idle to 10psi power had definitely increased, so that is great.

I have some other side-effects but I'm not sure if they are related or not. Drive pressure to boost ratio is up, when before it was closer to 1:1 until about 60psi where drive pressure would be 10-15psi over boost. Now it is 10-15psi over boost right from the start. Before, as soon as I got to 15psi of boost I could slam the gauge almost as quick as I demanded it and now there is a decent amount of lag. I'm hoping that these symptoms are all related to a possible small/medium boost leak or tuning needed since I also relieved area on the downpipe flange so that the wastegate can open further. Either way, there is no doubt that the divided housing made a positive difference in the lower RPM range.
 
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Thanks for the info! I haven't gotten anywhere on this. I had a few other issues with the vehicle pop up, and acquired other vehicles at the same time that have been sucking my time.

I'm pretty sure I'm going to do divided at this point with no cross flow until the turbine wheel.
 
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