Someone had to do it, cummins tubular manifold.

Jim Fulmer said:
The main ones to look at.

A version that I would like to build is a non-equal length(because it doesn't matter) a T-4 foot so the motor can breath with either a wastegate in the header like normal turbo motors run or one from E.D as it is the slickest setup out there. Tube sized according to H.P (the way gasser guys do it) and built out of stainless so it doesn't flake off the inside and beat the turbo up.

Spending that much time and money for a T-3 flange manifold seems like a waste of time to me. I'll be down at hotroddiesels this weekend, maybe Mike will have one there.

Last is why build a header like that then run three cylinders into one tube going to the flange, all the same size....is it just me!

Jim
Click to expand...

I was thinking the same thing, seems a little silly if they are the same size...
 
(This is about the 6 into 2 manifold COMP461 has)

^you mean like siamesed exhaust ports on older engines?


what about when the flow rate increases drastically due to high rpms? Even though a "constant" flow isnt encountered in each primary tube, when its all said and done the flow rate through the collected tube will be 3x the amount flowing through each primary


(or am i missing something relevant)
 
Typically, as-cast manifolds register around 1.5 square inches per T3 side prior to porting.
 
So really a t3 foot doesn't flow much more than each individual port?

I think when I do my manifold(s) I am going to put a t4 foot on them. There are a lot more t4 charger being put on these trucks.
 
just saying, what good does it do to merge three 1.5" primaries into a 2" merge only to neck back down to 1.5" again? :confused:
 
97crewcab said:
So really a t3 foot doesn't flow much more than each individual port?

I think when I do my manifold(s) I am going to put a t4 foot on them. There are a lot more t4 charger being put on these trucks.
Click to expand...

why would a T3 need to flow much more than each individual port? there's only one cylinder firing at a time, and on an inline 6 the cylinders are seperated front/rear consecutively, so you have a pulse going through one side of the turbo every third firing event.

a larger diameter primary and T4 flange and turbo can/will certainly flow more, but I don't see anything wrong w/ the popular T3 designs
 
2 Questions then:

1. If there is no dis-advantage in running tubes together then why even buy/build a manifold other than the (cool I got one factor).....insert data here......keep Log type and save 50% as they are cheap!

2. If the T-3 is so good then why even buy a T-4 Turbo unless you are talking about a 400 hp truck, I'm not....double that!

I now look at the stuff I was trying to do with a T-3 manifold/top turbo combo and it doesn't even make since to me, just 2 days ago I was talking to Brady about building a Silver Bullet with a T-4 housing.
 
Jim Fulmer said:
2 Questions then:

1. If there is no dis-advantage in running tubes together then why even buy/build a manifold other than the (cool I got one factor).....insert data here......keep Log type and save 50% as they are cheap!

2. If the T-3 is so good then why even buy a T-4 Turbo unless you are talking about a 400 hp truck, I'm not....double that!

I now look at the stuff I was trying to do with a T-3 manifold/top turbo combo and it doesn't even make since to me, just 2 days ago I was talking to Brady about building a Silver Bullet with a T-4 housing.
Click to expand...

oh, I hear ya Jim, but when we're looking at pics of a header w/ ~1.5" primaries and a T3 flange, I don't see a problem w/ it.

at higher power levels, going bigger is the next step :)
 
gitchesum said:
Ah, what the heck.
Click to expand...

little confused though In reply number #48, there is zero increase in horsepower and torque according to the chart. It does however look like the power comes on a bit more smooth though.
 
here is a cool set of headers for my Dmax
Greg at ZZ built these

100_0547.jpg
 
Would it not make more sense to have those headers go up to get the turbos as close to the intake as possible? Seems like 150mph wind is going to pull alot of heat from them.

I see the benifit of a "header" type manifold over a log. What I dont see is building the engine like a gasser or top alcohol. Equal length, tuned port, bla blah. Why are people doing this? Not to bash greg but changing fuels changes the build completely. Some stuff is the same but not all, so why?
 
roachie said:
Would it not make more sense to have those headers go up to get the turbos as close to the intake as possible? Seems like 150mph wind is going to pull alot of heat from them.

I see the benifit of a "header" type manifold over a log. What I dont see is building the engine like a gasser or top alcohol. Equal length, tuned port, bla blah. Why are people doing this? Not to bash greg but changing fuels changes the build completely. Some stuff is the same but not all, so why?
Click to expand...

exhaust flow is exhaust flow... it's just hot gas... doesn't matter what fuel it came from. look at the top turbo cars in the world. they're not running logs, I assure you
 
oh, and if you're talking about the intake side, air is air... doesn't matter what fuel it's going to be mixed with
 
I believe there is more to this than the one size/shape fits all mentality. I think diameter of the pipe has a lot to do with this. The ability to flow the needed volume at the correct velocity, efficiently is what these ideas are striving toward. For the everyday person the log style is great. Easy to manufacture and reasonably priced. It is still used in all of the turbo markets. Where we see the difference and improvements is in the vehicles that people think outside the box and push the limits.

I think we will continue to see T4 turbos become more popular. You can't tell me that the same motor pushing 300+ hp now should be using the same manifold as the 160hp trucks of before. Or that a 1000hp truck is efficiently using the same manifold that was designed for 200-300hp towing? Even if the pulses are independent of each other. The turbo holds up the flow.
 
Forrest Nearing said:
exhaust flow is exhaust flow... it's just hot gas... doesn't matter what fuel it came from. look at the top turbo cars in the world. they're not running logs, I assure you
Click to expand...

I know headers are a great bennifit, what I was trying to say is: These are not N/A engines. What good does the eqaul length do when the exhaust is runing into a restiction (charger)? A header is going to flow more than a log, I just cant see to over complicate it.

Forrest Nearing said:
oh, and if you're talking about the intake side, air is air... doesn't matter what fuel it's going to be mixed with
Click to expand...

The whole fuel thing:
You dont build a gasser like a nitro burner or a diesel like either. We all share some similarities. Last photo I seen of a top fuel engine had a flat plate to bolt the blower too. The only ports to speak of were to connect it to the head. No tappering, just get it in. They are trying to make that blower shove as much air as possible into the cylinders, same as us. If tuned intakes made a differance I think they would use them. I understand exhaust gas is just hot air, its what your trying to make it do that separates the designs of the exhaust.

But this is just my theory, I may be wrong.
 
You must log in or register to reply here.
Top