Agreed. Will likely need more than 10:1 compression too.

 

Excuse my ignorance, but what did that start life as, and what all was done to it?

 

I think it might be possible with an unlimited build, 12.0:1, 2.0L, vacuum pump oiling system, fully coated, E85. STL legal though, no. Even a "stock" STL port isn't stock.

We barely hit 180whp in ours before we discovered the road blocks and why 190-195whp STL motors are both grenades and stupid expensive. That's when I pulled the plug and used one of Oscars mildly tuned B6's in Super. Still had fastest trap speed in STL at runoffs. Diff magic + gearing =

 

Sorry...I was confused. Your post didn't say anything about stock cams, I thought you were claiming you had never seen a BP make more than 170whp on stock ports.

Other than a 1/2" of intake and exhaust port matching it has to be 100% OEM, at least that's my understanding of the rules. I was under the impression the allowance really doesn't make that much of a difference, but surely you would know better than I.

We never did any port work on our STL motors... #becauseK20

 

Last i knew, Quinn's car wasn't stock ports, either.

 

95 Miata with all EGR features cut out of and welded up it making slightly larger plenum and the head mounting flange modified to fit a 99 head gasket matched porting is done on both the manifold and the head.

 

There is genuinely stock then there is tech shed legal. Port matching helps on the BP's. We do it on SCCA and NASA dynio classed motors not on NASA points classed motors. Anyway, yeah, the magic in an STL motor is getting the cams just so. We stopped at 5 proprietary cam designs as we ran out of development time the blew it up and quit the BP. The tinkerer in me would love to build someone elses STL motor. Knowing what we know now, I feel confident we could build 190whp, 9000rpm that would last 10-15hrs before it lost much power. It would be the most expensive BP we have ever built.

Back to the OT, such a OEM-ish long block with stock cams isn't going to benefit too much with a B18 based manifold. Big cams and a B18 manifold would likely show gains of 8-15whp at high rpm over a square top.

 

Sorry to go off topic one more time but this is what drives me crazy about SCCA rules sometimes. Limit engine modifications to 11.0 compression, and .450" lift in the vein of keeping costs low. And in the end make a rule set where engine costs are astronomical, and engine durability is low.

:shakeshead:

Oh well

 

For B DOHC vtec B16A B16B B18 B18C5 Intake Manifold 70mm Silver Throttle Body | eBay Would this work as well? Not sure if I can trust that tb though.

 

Honda Acura Civic Integr B16 B17 PR3 B18C Type R Air Intake Manifold Aluminum | eBay

 

Would any b18 manifold work? I mean when comparing the skunk and victor and obx, I was wondering which one to pick from. I'm leaning towards Civic EK Integra Da DC2 B16A B16A2 B16A3 B16B B17A1 B18C5 Cast Intake Manifold | eBay because it's cheaper and it allow one to run a larger tb than the obx.

 

Kirby,

When you are accummulating negative props for posts, that means you should stop, not keep posting similar junk.

Just thought I'd let you know.

 

Thanks, just trying to get an answer is all.

 

The problem is, your asking questions that have already been answered many times. I'd suggest reading through these pages and then searching for an answer to any questions you might have. Then, if the answer still isn't showing up, make a post specific to the information you aren't able to find.

 

I have not read all 45 pages but the general consensuses seems to be OEM length is best and skunk 2 is too short. I disagree with that in the context of racing and 8k RPM redline. OEM's tune for lower RPM's on the street so it's hard to believe Mazda created the perfect manifold for racing and compromised street performance.

I have avoided this discussion for some time but will add the facts that I know from years of playing with intake tracks on other cars/motorcycles.

Intake cams play a role in determining proper intake length. Because the pulse wave oscillates from the backside of the valve to the plenum, (assuming non ITB's) as the IVC event and IVO event change so does the ideal intake track length.
Plenum volume seems to change the tuned length of the runners.
FI and the added volume requirements of boosted motors change things as well.
length of intake port is another variable to consider.

Even with all the math and proper formulas I have gotten surprised more often than not with intake length.

A well respected member of the community and a friend of mine dismissed the Skunk2 as being wrong for the job. He was very surprised with the results I got with mine. Would love to see results with a fixed boost setup.

The intake is not a one size fits all situation. Just like cams, headers etc it can (and should be) be tweaked to compliment your other components.

 

Anyone have any updates to this?

 

I run a skunk2 ultra street. Works great on high reving, ported BPs.
https://www.miataturbo.net/engine-pe...ing-req-83892/

 

I'll be putting a skunk 2 on an msm long block with a mild shave and rods with an upgraded msm turbo/ported exhaust manifold and upgraded exhaust and intercooler piping, curious to see results vs tuned vics

 

Your car is an anomalous animal. Good job with that! I would still like to see this intake on something with stock cams...