Well, due to many uncontrollable circumstances on my part, my other thread went to the crusher. So, I'm just restarting it, and adding something without starting another topic about it. Hopefully, it'll stay intact.

I focused more on runner alignment, more weld consistency, and getting a more consistent and defined haz. Collector is ported, flanges are welded on the outside and the inside.









For good measure I'll add the collector which I don't know what to do with. It's part of an abandoned plan, so I guess I'm gonna just make a mani for someone out of it. Dave@Passenger, you mentioned some scavenging losses resulting from the design, care to discuss or cite reference material?

I've read some material on collector merge angle, but never this arrangement. I'm curious what you've got specifically on the matter?






Modified by RC000E at 10:48 AM 10/27/2007

 

Fantastic job on the well-defined internal bead on the runner/collector joint. The only thing I can think of as far as that collector goes, is that it looks like it would cause unwanted turbulence from two of the runners basically pointing right towards each other at a 90* angle.

 

yeah...sometimes I get it and sometimes I don't to be honest. That's something I am working on. I'm also working on really getting my backpurge setup worked out more. I just am trying to get a feel with how much cfh I need it flowing at and what not. Learning day by day....it's all I can do.

 

As for the collector.

You can also consider the top two middle tube will flow downward, giving it a downward force, to actually decrease turbulence. Consider the fact that on how you actually position each runner into the collector. Just don't let firing order interfere with the two outside collector. Ya know what I mean?

 

Ehh....I was thinking more in terms of potential backpressure at the flange, as well as it's effect on the pulse wave rarefactions ability to scavenge the other cylinders.

It's pretty clear the outer cylinders will need encouragement to make the turn at the flange, but it still essentially should creat the reflective wave necessary to scavenge just like a typical collector. Dave, just made a comment in another thread about it, and I was hoping for a little more of his opinion in the matter.

 

Does a turbo clean on that mini ram ? Welds look good.

 

nice work, are you selling that? d or b?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RCautoworks &raquo;</TD></TR><TR><TD CLASS="quote">Does a turbo clean on that mini ram ? Welds look good.</TD></TR></TABLE>

I wish I had a turbo'd pipe polisher to clean that baby...lol

No, if you meant "clear", which is what I assume you mean, yeah I had it on the mockup block. The guy is running a smaller turbo, but it has an internal gate and still has about an inch to the block. I am gonna adjust my jig a tad to kick the turbo out further on future ones though just to be sure.

 

I think neukin did a manifold collector like that. Try it and compare it to another manifold you make. See when the boost comes in, and see what she does. Youve already cut the collector pipe, might as well toss in a couple 90* 45* and some straight and build something to see how it reacts.

 

yeah, it definitely won't be wasted. I actually just talked to a guy yesterday that lives down the road from me. He's infatuated with being "different", so I ran the idea by him and he's all for it. I was gonna actually build it on the jig for the manifold on my car, then do just what you proposed but it's not to be.

I'll be doing the setup on his car though, so I'll still get to get a feel for it.

 

when you talk about new haz... what is that in referal to? Why do you want the haz like shown?



Modified by silly sohc at 12:36 PM 10/28/2007

 

Ahh, well, I used to use a different gas lense/cup setup, and I used to ask AFI Jessi back in the day about his haz shapes cause I always liked them. Mine used to be kind of blurred and I always just wanted to change something and tighten it up.

So, on this mani I changed up my gas lense size, then went to a #7 cup. I also added a little more torch angle than I usually weld with. I got a definite increase in weld consistency as well as the haz shape, so it worked out. That's why I said new haz (for me).

 

Ultimately you do not want a HAZ in the weld ... why not strive for that ?

 

Because it's not a milk container I suppose. I understand a haz and discoloration is oxidation, but for the intended application, trying to weld haz'less, colorless welds really isn't necessary in my opinion.

To be honest, the haz now is much tighter and smaller than it was, so that in itself is an improvement.

I'm certainly always opened to constructive criticism, because that's what this forum is for, but I have to admit, I get the sense that your being condescending. If that's the case, save H-T the bandwidth.

 

looks great man!

 

no condescending intended... it great you are making improvents and that you know the fundamentals.

nice job.

 

Very nice tolerances on your collector cuts!

 

I read almost all the posts on the fab forum. This is a great looking manifold. Nice work.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BigMoose &raquo;</TD></TR><TR><TD CLASS="quote">Very nice tolerances on your collector cuts! </TD></TR></TABLE>

On people say the HF bandsaw's no good

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CSaddict &raquo;</TD></TR><TR><TD CLASS="quote">I read almost all the posts on the fab forum. This is a great looking manifold. Nice work.</TD></TR></TABLE>

Thanks bro

 

really stupid question but if i wanted tomake one of these what will i make it out of? mild steel?

also how do you guys make these do you start from the collector then go up or do you start from the flange then go to the collector or do the 2 halfs then tack them together then finsih the bead?


sorry 19 year old kid here trying to follow what you guys are doing LOL

 

I cut the collector, weld it inside and out, then cut the end. I then tack it to a turbo flange and bolt it into a manifold jig. I then mock up all the runners. Then I just weld the runners in whatever order I see fit, removing some if necessary. Let them cool, take them out, put others in...just depends.

You have to get creative in order to get what you want. Jigs help that happen alot easier.

 

how about the piping 2.5 or 3 inches? what does the jig look like i want to try to make one soon maybe within the next few weeks between school.

also was i correct with the mild steel? or should i use something else? stainless or something

LOL sorry for all ofthe questions but that first response helped man

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RC000E &raquo;</TD></TR><TR><TD CLASS="quote">
It's pretty clear the outer cylinders will need encouragement to make the turn at the flange, but it still essentially should creat the reflective wave necessary to scavenge just like a typical collector. Dave, just made a comment in another thread about it, and I was hoping for a little more of his opinion in the matter.</TD></TR></TABLE>

Sorry I didn't get back to this sooner. I'll try my best to explain the scavenging effect on these two collectors.

A traditional radial style collector should be paired with the firing order like this

1 3
4 2
so that each cylinder can scavenge off the next. Now with the flat style collector if you paired the cylinders correctly would look like this:
1 3 4 2
the problem is that after the #2 exhaust pulse has fired it can only scavenge #4's exhaust pulse which is 3 pulses away, what you really want is for it to scavenge #1. With the radial style you can accomplish this, with the flat style you cannot.

Don't know if that was clear or not so ask away if you have more questions.

 

I have to disagree with this theory. When an initial pressure wave exits the port and heads for the collector, it's a high pressure head with a low pressure residual "tail" which scavenges the cylinder it's coming from. When that pressure front reaches the collector, a reflective wave develops and flows up all runners, not selective runners. The timing of the reflective waves, and the rarefaction that goes with it is what gives you scavenging if timed properly through runner length.

I have to question what your saying, because I've never read anything that said scavenging is biased towards certain cylinders in a collector. I've certainly seen documented losses associated with more extreme angles of convergence, which this collector would be susceptible. Please explain further or give me something to go on literature wise.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RC000E &raquo;</TD></TR><TR><TD CLASS="quote">I have to disagree with this theory. When an initial pressure wave exits the port and heads for the collector, it's a high pressure head with a low pressure residual "tail" which scavenges the cylinder it's coming from. When that pressure front reaches the collector, a reflective wave develops and flows up all runners, not selective runners. The timing of the reflective waves, and the rarefaction that goes with it is what gives you scavenging if timed properly through runner length.

I have to question what your saying, because I've never read anything that said scavenging is biased towards certain cylinders in a collector. I've certainly seen documented losses associated with more extreme angles of convergence, which this collector would be susceptible. Please explain further or give me something to go on literature wise.</TD></TR></TABLE>

The thing is that high pressure head is what creates the scavenging, and it creates a vacuum or scavenging on the next nearest low pressure area. (an exhaust crankcase evac is a more common example) Utilizing this in cylinder pairing makes a big difference, you can quite literally physically hear the difference, of course to utilize this you also need true equal length (and as close as you can matching radii) for your primaries.