Wow, whats the weight balance after the swap? 48-52 or something?

It's at least 50 lbs lighter. So far customers are telling me they are saving at least 100 lbs total by completing the swap since they are doing some further weight reduction in the process (mainly A/C and P/S).

Last time we weighed our car (2000 NB) it was under 2300 lb.
K24
Full interior
OEM hard top
OEM soft top
Roll bar
Spec Miata seats
No spare tire
Almost full tank

Weight distribution is exactly 50/50

Emilio your car will most likely be the best back-to-back weight test.

Yup, we're not changing anything other than the engine and swap kit. Car has no A/C, PS or emissions equipment as is.

That said, the dressed long blocks weight about the same so on paper at least, there should not be much of a difference. My guess is the alloy block being a full girdle type and the much taller head (because real ports) account for the disparity in block materials.

AC parts + power steering + emissions, the custom intake, subframe, cruise control, and header should add up to about 65lb in weight savings. If people are coming from a stock flywheel there is a big chunk of weight there as well. About 25lb difference between the two long blocks?

Nb ac stuff is 32 lbs by itself.

Finally did this. In addition to the FB page (OneLapMiata.com), I put the whole build-up on this forum.

https://www.miataturbo.net/general-m...2/#post1204024

The FB page gets a little hard to follow after awhile, so this will serve as a reference for others doing this build.

Not looking good for hood clearance on an NA with K24. This is after the bracing is cut out in the affected areas... basically hood skin on valve cover.

Suggestions?

Current plan is to pull the valve cover and see how much room there is to shorten it.

Sell me the K24a2 (a2?) for cheap and then go K20? :)

I have an X1/9 now that needs a K at some point in the future...

13mm more stroke on the k24 but are the external dimensions different?

Cowl Hood. Only solution.

Cowl hood will require proper decal.


https://www.miataturbo.net/attachmen...ine=1424653978

Deck height is ~20mm different.
06 K24A2. ;)

It's basically a track only car so I have no problem going street rod and cutting a hole in the hood for it. Just keeping that as the last option.

Damn... (that I can't get it for cheap :p) I'd see if you can find an old school metal guy to massage the metal up to clear it. Could do simple hammer attack... but old school hotrod guys could likely do it cleanly and then polish (heh) or repaint that area when the paint cracks during the work.

Shoot me an email, we already have custom valve covers that have better clearance in the front. I'll post some pics soon. Since you're local you can come pick one up to test fit. You can make the stock hood clear.

You have an email. :party:

And here's a sample of the valve cover prototype.

Note that a K20 and K24 clear fine in an NB with no cutting of the hood skeleton.

K20 in NA should be fine with some trimming, and K24 in an NA requires some trimming and a modded valve cover, or a hole in the hood.

All things we are learning along the way!

edit: we have 5 of these valve covers being modded right now. We'll do a core exchange for our NA K24 customers starting in the next couple weeks. Haven't even gotten it on the website yet.

Threadjack . . . but you guys HAVE to see this car:

The Bandit Is For Sale!!!! 2001 Spec Miata Vvt - Spec Miata Classifieds - Mazda Racers

SO GOOD.

https://www.miataturbo.net/attachmen...ine=1424792725

One more option for NA...

You can put a K24 into a K20 block. Requires either custom pistons or custom rods, but it is done frequently (especially by CRX owners).

Very stealth.

but mah r/s ratio.