Your Intake Manifold and You

This evo would hand my car its ass on anything that isn't straight. And it'd still be close in a straight line.





RWD will come later in life when I have money to buy something special

 

Where's it up for sale at? I wouldn't mind taking a look.

 

I'm so anxious to receive. Its almost to good to install.

Really keen to see how it performs when i build next year and switch to 100% e85


Sent from my iPhone using Tapatalk

 

Right now only fb. I need to make signage for the forums.

 

Sorry to try and revive an old thread. I’m considering single porting & gasket matching runners 1&4, and only gasket matching 2&3 to equalize flow on the stock manifold. Flow would be balanced (to an extend), but velocity will be effected. What are the draw backs and how would it perform under vacuum?

 

you'd barely notice a difference compared to stock.

 

Just get the focus ST manifold if you want even flow on a budget.

 

Did the CS mani ever get tested?

 

I totally get where you're coming from - other mani's don't have the same capabilities emissions-wise. I would presume that under idle, your configuration would do the same thing as the VTCS - increasing air flow speed of the 2/3 cyl air. I would guess this would be true under non-boost conditions as well, but since I don't have time to do the math, if someone has looked into this, please chime in.

EDIT: It almost seems that if you removed VTCS, lightly ported Cyl1, did not port 2/3 and single runner ported cyl4, you would get an almost even flow across all 4 at around 200ish. Then, if you had a flow tester, you could continue lightly porting all 4 until they matched cyl4's maximum flow.

The only issue I see with single runner ports is that the head has a divider that matches the oem intake mani runners, and that divider would need to be ground down to a shape that's less square to avoid turbulence.

 

I'm still porting a spare IM and had an idea about a doing a single port version. Take the holes for the VTCS shaft and use that as a template to erase the space between the two ports for each runner. Essentially you'll still have a split between the runner however you can knife edge it for smoother flow

It would work better than gutting both of them into one large port and then having the air ran into a flat 90 degree edge on the head side. Just use the floor and roof of the existing port area as a reference.

 

@AYOUSTIN are you still able to do flow testing and willing if someone gets you a CS intake manifold? an unnamed source has one and I'd be willing to cover shipping costs for science

 

I know this is an old thread but I see it’s almost back from the dead. I would like to share what I did to my manifold. I’m not saying it’s perfect but I feel like it flows more and more evenly than factory, but only works if you have a front mount intercooler. Central throttle body, big single port runners with welded Vcts holes, PI on a factory manifold using Honda K20 bits for availability and cost.

For me the cost was free because I have an aluminum welder at work. I had to extended the TB wiring about 12” and that gives me some slack.

This is on my built motor running that has methonal injection at the throttle body as well.

When I built my motor 1/2 cylinders were clean like meth was only getting to them, and 2/3 cylinders the ringlands were blown out so I believe what I did should even everything out.


Go ahead, flame or flambé away. Lol

also the head is knife edged and matched to a single port gasket. I’m running 25psi of boost

 

Missed opportunity to knife edge that shit in there, and clean up some flashing that's probably around. Be interested to see it on the flow bench.

 

Yeah flow bench is what I'd want to see on that manifold otherwise "meh" hopes and dreams with good intentions, and heck we've seen porting on stock manifold make flow imbalances worse

 

Interesting idea for sure

 

What was the piping solution you used for this? I'm hoping to go ST Manifold during my big (lol) turbo swap in the winter and will need a new piping setup to accommodate the vertical throttle body.

 

Probably similar to how I was going to run mine before i abandoned that idea:

 

You were going to do Meth-only cooling right?

 

Chemical only yes.

Edit:
It wouldn't be the first time, either.

Pics taken from a friends house:

 

Speed Solutions makes a cold pipe that is a decent off the shelf option.

Other guys have made their own from parts or by modifying their existing piping:
https://mazdaspeeds.org/index.php?t...ll-and-how-to-keep-your-existing-piping.6195/
https://mazdaspeeds.org/index.php?threads/masterminds-build.3797/

Its not that hard really, just depends on your FMIC setup and preferred routing.