I already shipped it, Ill send the tracking number.

Just throwing it out there, that my intake manifold from this guy is awesome and you should all buy one.

Bookmarked for next year. This is much better than those JDM squares.

Thanks man, glad you like it.

does anyone know how to get a hold of gotpsi? i wanted a quote,i thought he had a site but i cant find it?

http://www.rpracingproducts.com/

Finally getting that manifold welded up?

--Ferdi

Hey guys, this is gotpsi, I have not been able to post or pm so the best way to contact me is through my web site listed above thanks.

i failed at making one

Thanks for that informative post

[IMG]https://www.miataturbo.net/attachmen...ine=1340773912[/IMG]

[IMG]https://www.miataturbo.net/attachmen...ine=1340773912[/IMG]

[IMG]https://www.miataturbo.net/attachmen...ine=1340773912[/IMG]

Here is some newer pics, and one of a flush mount velocity stack done recently.
Also shown in the pics is the new tapering runners.

NICE! Great work man...beautiful welds, rockin' velocity stacks! How tough was it to get them that flush?

It's easy to get them flush, the raised ones are harder.

Any reason for the taper on the runners? I noticed both you and begi started doing this with the most recent mani's

If you want to get scientific search for Venturi nozzle and Bernoulli. Interesting stuff.

To encourage uniform and smooth transition from the chamber to a high velocity runner, sharp edges tend to create turbulence which acts as a bottleneck to flow.

I'll look into it, thanks
isn't that what the velocity stacks are for?

sounded like he was explaining what the velocity stacks are for to me..

Just think of a tapered runner as a very subtle velocity stack. By starting out with a larger diameter than the intake port of the head the effective unrestricted flow area can be equivalent to that of the head intake port diameter.

Notice the smaller unrestricted flow CSA (cross sectional area) in the top image. this same effect happens at the base of the velocity stack although it is not shown in the picture. The tapered runner helps combat the effects of this turbulence.
https://www.miataturbo.net/attachmen...ine=1340813107

I get it, thanks. I guess what I should have asked is how significant the effect is (ie: how much you actually gain from it) but I have a feeling that has yet to be measured.

it's just good practice. you want good flow: use a stack. you want to stuff a ---- ton of air as fast as possible into a container: taper the runner to increase velocity.

Higher velocities usually mean a smaller boundary layer and a more turbulent flow which is good for air fuel mixture as well.

I just stumbled upon this thread and love it. Props to you Ryan for bringing a much wanted product to the Miata world. It seems as if I may be a customer in the future for my build. I will contact you via email or your website so we can discuss what my options and goals are with my '99 NB.

I was hoping to use ARTech for an intake manifold as I will be utilizing his exhaust manifold and dp but he has been so swamped with work his intake manifold developement has taken a back seat.

Anyway once again thanks for all your hard work.

Gregg ;)

Bringing it back from the dead
 

Hi all, its been a log time since I've had anything to post but I had a recent manifold build I thought I would share.

1.6 manifold with stock throttle body, velocity stacks and tapered runners.

https://www.miataturbo.net/attachmen...ine=1416001878

https://www.miataturbo.net/attachmen...ine=1416001878

https://www.miataturbo.net/attachmen...ine=1416001878

Do you hae any dyno results of your intake manifolds on a Miata 1.8, NA or FI, which you can share?

Also, please PM me pricing on a "typical" intake manifold for a NB2 1.8L VVT engine? I will be using at least a Skunk2 TB, but could switch to a different one if needed (MS3X ECU).

Thanks

There was a dyno comparison done by another member on here a couple of years ago, I'll see if I can dig it up, it may be buried in this thread somewhere. I can certainly tell you or you can ask anyone on here that has used one of my manifolds that it broadens your powerband dramatically, especially with larger turbos and cams.

Nice work. You still in the Bay Area at all?

Every time someone makes a pimpy intake manifold and puts the velocity stacks on the floor of the plenum I die a little.

Every time someone fails to read the whole thread I die a little.

I still have my shop in the bay area, but I'm in Texas most of the time these days. I've been setting up a new shop in the temple area and Ive been working on a piggyback flex fuel system that will work with stock or aftermarket systems. I'll start a thread about soon.

No I did read the thread and it showed you are perfectly capable of making a manifold that uses velocity stacks properly, which makes your use of the floor mounted velocity stacks even worse.

They are made to order. not one is the same as another. This one also is using a stock 1.6 throttle body. I believe this is the first one I've done with a throttle body the same size as one velocity stack.

I really want to get a proper turbo intake once I do cams, I want a bigger tbody but don't want to lose the street-ability of my tbody+IAC setup...

You can do a remote mounted idle valve. I use a 97 IAC that TurboTim made a block off plate for and have it mounted off to the side. I use it in a mustang throttle body. I will try to snap some pictures later today.

That would be appreciated!

If you could give me the part number for that I am valve that would be great I would love to recommend them. Most people don't use anything because they are usually on a track only race car that doesn't have any accessories. But for a street car that could be handy.

Sorry I have not gotten pictures yet. Has been raining out the past few days and that car is not in the garage. Hopefully I get a sunny day soon and can snap pictures.

I believe that it is just a stock 97 IAC that was unbolted from the throttle body.

I've heard of a Volvo I actually that is external as well but never figured out which one.