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Discussion Starter #1
Some of you will remember our 95R Street Project car from about 5 years ago. That later received a race engine and C30-74 Rotrex from Jackson Racing. We set that hardware aside for a future project then ordered a K swap kit from KMiata. We started this about 18 months ago. It's getting pretty close to first start. Not finished yet but I wanted to share pics. Much more detail on build in this thread:http://www.miataturbo.net/general-miata-chat-9/deviate-gets-k20a2-82901

I chose to take a different path from everyone else by building a K20A2 and not the much simpler, and less expensive K24A2 conversion. Beyond that, we decided to push the motor higher up the rev range. This meant building what is basically a full race engine and not just a mildly modified street engine. The engine is chock full of expensive blueprinted bits to let it survive at a sustained 8800rpm, including a huge 7qt custom aluminum wet sump oil pan and external oil pump.

We will have it on the dyno in a few weeks and think it will make about 250whp on E85. On a related note, we have a Quaife QBE60G sequential trans on its way for our OGK project. The trans will get here well before the OGK is ready for it so we're thinking of trying to install it onto the back of the K. Oh the sound!

We will upgrade from the current 15x9 6UL's to 15x10 6UL's with 245/40/15 Maxxis VR-1's (200tw). http://www.maxxis.com/catalog/tire-513-vr-1
This will require some slightly wider fenders so we contacted Dave Green of DG Motorsports. He's looking at possibly doing a set of ~30mm wider complete front and rear fenders just for this tire combination. NA and NB, they would not be rocket bunny or GT style. They would be smoothly integrated into the OEM body lines, just wide enough to cover the tires safely and no more.

Contact kmiata.com for more info on their K swaps.




Round things


This is the reinforced cut out in the PPF for the exhaust to cross over to the left side.


-12 feed and hardline for the vacuum pump system.


Pic from 5 years ago. Looks pretty much the same today
 

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We had a K swap miata at our local autocross this past weekend. It was beautiful.

Sent from my XT1585 using Tapatalk
 

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so much awesome from 949racing. as usual.
 

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sheesh, you guys make me wanna go this route.
 

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Discussion Starter #7
This is so cool. K20 looks great sitting in there. There's too much extra room, compared to LS swaps. Good stuff!
Yup. OEM trans, diff and axles too so a lot simpler than LSx. Our was made complicated by choosing a very high revving K20. Do a K24 like everyone else and it's much simpler, and cheaper. 230whp on pump gas on a junkyard K24 for years. It's a Honda after all.
 

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Yup. OEM trans, diff and axles too so a lot simpler than LSx. Our was made complicated by choosing a very high revving K20. Do a K24 like everyone else and it's much simpler, and cheaper. 230whp on pump gas on a junkyard K24 for years. It's a Honda after all.
Stupid autocorrect on my mac changed "so" to "too", but you got the point haha. Either swap is out of my budget, but seeing this done is awesome. I'll live vicariously through your success with this amazing job. Cheers!!
 

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Discussion Starter #12
How much would you say you have in that swap?
Way too much. Like I said.. on another forum, If I knew what I know, I would have stuck with a junkyard K24A2 and the standard kit with a much lower redline like Kmiata recommends. I wanted the most revs we could reliably sustain and still have Vtec function. That meant a built K20A2 and custom oiling system. I was already too deep into the build when the realities of my projects goals hit the calculator. Too late to change course so I'm finishing it. It will be glorious and for sale all at once :)

For 250whp, it would be cheaper to either buy a TSE 6258 turbo kit on a stock long block with forged rods, or maybe wait a few months for the Jackson Racing Rotrex kit on a similar motor. Both of those combos will find 250whp for the kit plus ECU, injectors and a few extras. Maybe $8k in all where a K24 that makes 250whp on pump gas will run over $10k done right. Drop your power goal down to about 220whp on pump gas though and the K is in the sweet spot because you can do that reliably without building a new motor. Just the VTC gear and oil pan mods on a healthy junkyard TSX motor and you're set.
 

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:subd: in for review of that gear box. I'm guessing from the videos that it self-clutches or is the 3rd pedal still required?
 

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Its a sequential box. So clutch to get going. And then flat foot shift on the way up. You set the ecu (MS3 supports this) to cut power when shifting. You use a sensor to determine the gear shifter is moving, power is cut, shift, apply power. All without lifting off the go pedal.
 

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Discussion Starter #19
:subd: in for review of that gear box. I'm guessing from the videos that it self-clutches or is the 3rd pedal still required?
No plans for a review, sorry.

A spur gear sequential is basically like a dog box. Google that if you are curious about how they work. 2 Shift 1 you just need to cut input shaft torque. This is usually done with an ignition cut triggered by ECU based on sensor input. Either drum position or force on the shift lever. We will be using a load cell built into the shift knob and sequential control feature of the MS3 Pro. Or you can just lift off the throttle momentarily. So the clutch is not used for shifting a dog box or sequential. The clutch is still used for launching of course.
 
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