4. Cat people.

1a. Former turbo, now VVT guys.

C

That's more or less mandatory to be accepted here :party:

My work here is done :brain:

I'm just glad that I didn't have any money when TSE was not even a faint idea in Sav's head.

I may have made out with buying stuff at the right time for NA power; however, I lost out by buying FCMs a few months prior to Xidas hitting the market.

Thanks again for your testing work Emilio! Small question for you, I have a VVT motor in my racecar with a Jackson Racing header matted to a Jackson Racing Cat going to a Bosal made Mazdaspeed Spec Miata exhaust. I recently swapped from a VCTS manifold with butterflies to a VICS manifold with the butterflies operating at 5400rpms and I gained 14hp at 7k. I just added a euro, flat top, manifold and saw no change in power. Could the smallish Bosal (1.9" I.D.) be limiting my power? I have seen typical gains with the euro manifold occur above 6k, but I saw no change. Thoughts?

The good thing is that this combo makes 120ft/lbs of torque by 2200rpms and only goes up slightly thru the rev range falling off up high as expected, but peaking at ~130ft/lbs around 4500rpms.

It is not the exhaust. Something in your data is wrong I suspect. If you are using the stock ECU, thats the problem.

This is why I don't really want to do anything beyond an ex/intake cam on my 99 without getting an ECU first.

Don't forget the few lurkers with their stupidchargers...

I suppose I am just the lone wolf.

Sorry, I should have made that more clear. I am running a VVT motor in my '90 using a DIYPNP and VVTuner combo. I am making 139hp and 130ft/lbs, but my goal for this swap was to get into the 140's.

https://www.miataturbo.net/attachmen...cs-vs-vcts-jpg

Here is a copy of my last dyno, the red line is the VICS manifold, the other line is the VCTS, with butterflies.

These dynos were taken almost 6 months apart. Do over.

Got dyno from VICS to square top?

I do not have that here. I need to take my flash drive over and get the data. I was organizing a Dyno day and forgot to grab my sheet when I left.

Can you elaborate on the "well designed intake" Basically how you did Crusher?
The U bend and keep it on the cooler side of the engine bay?

I wonder if anyone has tested the b18/b16 Honda intake mani retrofit vs. the jdm squaretop. I would think the squaretop might have a better midrange but the honda setup will have more top end. Building a honda intake manifold is one of my winter projects.

I always get asked this. A 2.5" tube about 21" long with a cone filter. That's it. Don't over think it.

Honda manifold makes more power everywhere provided the runners are long enough. The trick is getting the runners the correct length, aligning them with the ports and clearing everything on the coldside of the engine bay. I have yet to build one I'm really satisfied with. Kicking around the idea of giving up on aluminum protos (expensive) and just printing one. One of the engineers I consult for various projects can draw it. Several SLA printing facilities nearby. Yup, that's what I need to do.

I support this

Pretty much yeah. And the people with turbos waiting for their engines to blow up so they can VVT swap.

Given any thought to printing it in ABS and then wrapping it with FG or CF? It how we made the formula car intakes. And they seem fairly resistant to cracking considering they were normally at a much larger cantilever than a miata engine off of an engine that shakes considerably more. Disclosure, I've never run the same one for more than 10 hours.

I'll donate time if I can help with CAD modeling in any way. I do not know how to properly use the CFD add-in in solidworks though.