Looks great 2a+RoN. Nice fabing.

Justin

 

Now that's a good looking radius from what i can see on my computer. I'm suprised to see that. Most people do the raised velocity stacks which we've found to actually hurt flow and make tuning a pain in the ***. I think you'll be really happy with the balance.....again from what i can see on my computer.

Good job!

 

That's something I learned many years ago. The raised velocity stacks just don't cut it on a boosted application from my experienced. One particular intake setup just lost all the power above 7.5k rpm. where as the same intake with the stacks sitting flat made power all the way to 9k rpm not to mention the tuning made a lot more sense I guess due to there being a lot less turbulence in the intake.

 

I will follow in saying I couldn't agree more I run the same setup in my intake as well. My reasoning was the stacks would create turbulence in a enclosed plenum.

-S-

 

There is nothing wrong with velocity stacks extending into the plenum. It works fine. The issue is plenum volume. In the case of this manifold, if they extended into it there wouldn't be enough area for air to move around them very well which would explain a lack of performance if there was one. If you make the plenum large enough, it won't really matter. I personally prefer them flat though as I like how open it keeps the plenum.

 

I don't doubt they work. They're proven to work. I actually had the issue of a smallish sized plenum, and saw them as being in the way and creating more issues than if the plenum just had them incorperated in the base. You also run into other issues with a plenum being too large and I bet the velocity stacks help resolve some of the issues associated with it.

-S-

 

I've always used the velocity stacks on n/a applications...

 

Like Crispeed said and i agree 100%......the raised velocity stack on a boosted application just don't cut it.

We've tested different manifolds and ALOT of different designs and none worked like the one pictured. It was soooooo much quieter on the flow bench which basically means it's flowing smooth.....better flow means more power and a higher and more stable tuning process.

I know one manifold we tested that had a larger plenum than ours and it also had raised velocity stacks.......it didn't even come close! It has been used on many cars with all things being equal and mirrors the results on the flow bench. Tuning it is a nightmare and it makes FAR less power.

 

Can someone post a picture of a intake with raised velocity stacks? I want to see what you guys are talking about.

 

About how high were they raised? I'm curious. On NA apps I could see how they help. On boosted apps I would bet no more than having them resting on the base would be about it. With them being incorperated totally like in mine and pictured above would be best. I have a much better thought on a base design just need to get around to it.

-S-

 

Here is how we've done them in the past on the GE Supra motors ( n/a)

 

How about a picture?

 

This was my exact train of thought as well. I'm glad what I did actually turned out to be what works best in your guys' experience.

 

Ask and you shall receive.



This 20b is NA and not turbo.

 

Yeah n/a those stacks work great......boosted applications don't like them one single bit.

Zero R: they were up about 3/4" inside the plenum which doesn't seem like much.....but boy did it have a negative impact.

 

Yeah what I'm thinking is none, like you and Crispeed and I are saying, seems to make more sense since the air is being forced in rather than drawn in. I didn't have flow bench to go play on but everything I know tells me they would have hurt my app. If I could change one thing on mine I would have the base radiused as well, ie no flat floor. Air don't seem to like corners too much, but I would bet at 3bar it matters less. Even still good flow is good flow.

-S-

 

so no to velocity stacks... even the ones imbedded like of the entitled manifold in this tread? someone said make the runners run flat into the plenum...???

 

You guys shoud check this intake out:
http://www.rossmachineracing.com/large/4g636.html
That same place sells all the materials to build some nice aluminum manifolds. they sell the velocity stacks etc. check out their intakes they sell fro the mr2 and stuff. nice stuff.
http://www.rossmachineracing.com/billetintakes.html

CJG

 

those look nice. I didn't go with aluminum with mine b/c 1) it's more expensive and 2) aluminum transfers heat very well, and I didn't want to transfer any heat knowing that the runners would have to be so close to the dp and turbo..

 

C'mon it's much more fun to weld.

-S-

 

I've used the Ross MR-2 one. It works great. A fine piece of work too.

 

Yeah, I've only welded AL a couple times, but it is kinda fun, you gotta haul ***.

 

no to velocity stacks but yes to the ones pictured in this thread

 

They do look pretty nice don't they? That's actually the 1st time i've seen them. They're radius looks sick!

 

Excellant work , I like it!! also doesnt it look a lot like DEE KARAGANIS manifold, (Ihope I spelled his name correctly). keep up the great work any way!