Good chance they will not, I haven’t seen many positive review from either on something they didn’t develop.

 

both of them use the flattop.

 

Emilio recommends the Racing beat 4-1 as the best current, OTS header for Rotrex/NA builds

 

Or Skunk2 throttle bodies as long as you do the mods to make it reliable.

 

What's the OTS header? Sorry for the ignorance. Looking forward to 949's results.

 

I was hoping for a slightly shorter one for track performance. How long are flat top runners? Look forward to seeing more dyno results.

I would not run it without a brace. I fought crack on mine without one.

 

Off The Shelf.

Emilio also recommends the K&N intake as OTS and the Koyo Hyper-V radiator, should you not buy the SuperMiata CSF. The associated statement is patently undeserved.

 

The cracking is likely irrelevant as this manifold is cast as one piece, not welded together. From what I recollect, the welding anneals the metal around the bead causing it to become harder and more brittle.

 

Shorter for less torque with a Rotrex?
I'll take long runners thank you. I thought I read a post somewhere that the runners are 10" on the Skunk2 (have not confirmed this myself). That's exactly the right length for this type of manifold. Gordon (trackdayhookey) did a bunch of testing with runner lengths and ended up within 1/4" of OEM with his 450whp Rotrex car.
It's a function of the displacement, RPM and cams. Peak power wins drag races. Area under the curve wins road races.

 

lol looks like you're unloading your stash sooner rather than later, eh?

 

lol. If it turns out this manifold is junk they'll go back up. Anyone care to speculate on the intake manifold futures market?

 

Just to clarify, it's the weld bead itself that is hard and brittle and prone to cracking. The heat from welding does anneal the material around the bead (known as the heat affected zone), but annealing makes a material softer and therefore weaker. Regardless, the effect is still the same. Welds are highly prone to cracking, especially in cantilevered joints like the Skunk IM.

That being said, I agree that the one piece cast design should be far less prone to cracking than the welded design, though not impervious. A poorly designed or poor quality casting can be prone to cracking too, especially in a high vibration situation.

 

I am not sure of my current honda skunk 2 runner length. It sure looks shorter that the 10" Miata one. I was hoping to keep the same length as it really works well with the rotrex. The torque curve I have is flatter (5k-7k) than I expected it to be with 99 head and rotrex. I agree area under the curve (5.5k-8k in my case) is what I want.

I followed Gordon's intake manifold work. He did go really short with one of em and made a peaky HP monster. I have no desire for that. If my current Honda skunk 2 is really 10" I'd be thrilled with this new Miata setup. Looking at the posted dyno it looks like HP was really starting to take off at 7k.

 

Haha, if test shows squaretop is on top then I win, but either way it's cheaper. The one I sold earlier this year simply reflects demand at the time, who knows.

 

I have a square top that I picked up, was ready to port it for my skunk 2 TB but I will wait for results on these. Like some others said, it would have to perform a good bit better than a square top on a 300whp car for me to buy it. Prefer the look of the OEM one more than the bling and branded Skunk 2. I haven't had any issues with their Throttle Body, but apparently others have, so it kind of turns me off from the brand a bit. Not even sure what these issues are

 

Just showed up, don't think we'll have time to test and tune this before Miatas @ MRLS.


Looks pretty decent.


Weighing in at 10.1lbs.

 

Any way to adapt the stock brace?

 

Anyone got a stock intake manifold laying around they can weigh? Doesn't look too bad.

 

Won't know until we get in there, here is a shot of the bottom of it.



Going to weigh some here shortly.

 

Flat top manifold weighs 11.5lbs without a throttle body or brace.