Honda V6 Miata in the Aug 2014 issue

Just got my hands on the article. There are some errors and glossed over bits.

• gearing. Going with a 1999-03 six speed with the 3.909 will not fix the gearing problem mentioned in the article. The six speed has shorter gears than the five, so you'll still be spinning pretty quick. 80 mph drops from 4080 to 3841 rpm according to the Flyin' Miata gearing calculator.
• rear end. The stock 1.6 rear end is known to self-destruct under the strain of a stock 1.6, so saying it's robust enough to handle a 300 hp V6 is stretching the truth. It's quite possible that a single example has withstood a year of use by a particular owner, but I'd be tensing up every time I dropped the clutch at an autox. The 1.8 rear should be fine.
• transmission strength. We've discussed this already, of course. 300 hp is in the danger range for stripping teeth. MiniTec might claim it's up to the task, but a couple of decades of Miata turbo experience would argue otherwise.
• CARB. This is a huge thing. These engines only came in OBD-II cars, so you need to retain quite a few emissions bits. Do the headers and cats from a FWD minivan really fit? Will the stock ECU be happy with other monitors such as the charcoal canister or fuel tank vapor control from the Miata? Is the modified intake CARB approved? This is the sort of research needed before that question can be answered.
• Have the AC and PS systems been figured out yet, or are they things that can probably be done? Getting AC systems to play together can be surprisingly difficult. Flyin' Miata does have some of the parts that may be needed to make that PS setup work, assuming the pump output is appropriate.

I look forward to seeing this thing in person at the Mitty.

Now if only we could get the MT motorsports guys out there for you to see too

I would recommend finding a non-Honda PS pump. The Honda ones seem to suck. A lot.

Or just remove the PS.

For me, the appeal of this swap is that it keeps the Miata trans and diff. Fewer parts to futz with during the swap, fewer parts that aren't 'factory fit'. I'm rather fond of the feel of the Miata 5 speed. This swap lets me keep that.

If the V6 torques make the Miata trans 'splode ocassionally, that's OK. We put a new-to-us junkyard trans in our Miata powered FC race car every season. We spend about $225 and an afternoon each year doing that.

Have any of these been sold and installed?

absurdflow wrote: I may as well chime in here. My V6 swap (Mazda KL 2.5l) fits under the factory (92) hood, uses the factory subframe (one new motor mount though for starter clearance), and I'm currently running a factory 3.90 torsen with a ford T5 trans. The miata PPF bolts to the T5's cross member, which bolts to slightly modified FM subframe rails. It works quite well and gives me decent adjustment on pinion angle, and saved me a few grand on the swap. My point being that running the factory rear isn't that difficult in these swaps if you decide to switch the trans, and modifying the Honda V6 intake hopefully won't be difficult either. Or milling a new intake from a chunk of aluminum is another option for relatively little compared to the total costs of a swap. While I have never driven a V8 miata, I think a rev happy responsive ~250rwhp NA would be near perfect and of course V6 exhaust notes can be 'joyful'. Then again, you can always boost the V6. I've worked my way up to 12psi at the moment and it's...interesting.

oh that's just pretty.

Not that it doesn't work, because it works incredibly well, but the Shelby take a small car and stuff an american V8 in it has been done to death.

I think a low cost V6 swap would be great.

icaneat50eggs wrote: Have any of these been sold and installed?

I ordered my kit 1 week ago and I was kit #10 sold. I believe there are 3 that they have done in-house (2 prototype/demos and a customer car), and I know of 2 others that are under construction/nearly done.

As for the questions of Power Steering and A/C, this was the answer I got when I asked them: "Air conditioning and power steering are both connected in our demo cars. We use the Honda compressor and power steering pump with custom fittings that will be available."

Titus please tell me your documenting your build

icaneat50eggs wrote: Titus please tell me your documenting your build WITH HUNDREDS OF PICTURES HERE STARTING IMMEDIATELY! LIKE RIGHT NOW! DO NOT PASS GO, DO NOT COLLECT $200!

Fixed.

Junkyard_Dog wrote:

icaneat50eggs wrote: Titus please tell me your documenting your build WITH HUNDREDS OF PICTURES HERE STARTING IMMEDIATELY! LIKE RIGHT NOW! DO NOT PASS GO, DO NOT COLLECT $200!

Fixed.

Yes, I will be. I will start it in a few weeks once I have everything, and my shop has been given a thorough pre-build cleaning. For now, I will leave with a teaser....

Twin engine!!!

Where do you find these cheap engines?

I found the pair on car-part.com from a yard 2 miles from my house. $660 for the 2 including tax, core fee, and delivered to my driveway.

I'm confused! Why would anyone want to put a V anything motor in a Miata? You already have a sweet DOHC inline motor that has a ton of potential. Why don't you use that as the basis of your hot build? It's not like there aren't tons of alternatives out there. Cubic inches are great if you're pulling a huge tractor or semi rig or even a boat. My twin 502s were very handy on my 45' boat. But they are much less an advantage when propelling a 2,300 lbs. car

Other than a V-12, there is no sweeter sounding or driving V-motor that I know of than a typical inline motor, OK an inline three isn't sweat, but that's not what we are talking about here. That's certainly not typical. And you can actually access and work on your inline motor without an engine removal or other serious cure to obtain access!

Please don't even insult your Miata with yet another sbc, sbf, or even Honda installation! From the factory, the Miata motor with all it's potential is already better than those!

That was a joke, right? The Miata motor is great because it came in a Miata. The Miata isnt great because of its motor.

It's durable, but not great at anything.

The one thing the miata is missing is power. If you can correct that without compromising the attributes of the car or reliability, then why the hell not.

I'm personally not a fan of this particular swap but he's trying fix what is missing from the car. Besides it's a miata. They're a dime a dozen. If you screw it up it isn't hard to get another to start over with.

Rupert, have you ever driven a miata with a motor swap(excluding SBF's)?

Titus, what widebody stuff is that? Molded AWR kit with Racing Beat bumper?

Also: Simspon Designs hood?

Swank Force One wrote: Titus, what widebody stuff is that? Molded AWR kit with Racing Beat bumper? Also: Simspon Designs hood?

Exterior mods include Racing Beat Front and rear bumper, AWR full front qtrs and molded rear qtrs, beltline delete, stock hood with custom power bulge molded in, stock truck lid with custom lip molded in, Track Dog Racing splitter, and I am sure a few more bits I can't remember. I have had the car for 14 years now and it has gone through many changes. All paint/body work was done by forum member Rogue.

what engine did you go with? what are you doing for computer?

icaneat50eggs wrote: what engine did you go with? what are you doing for computer?

J32A2 from a 2002 TL Type S. I picked up a stock ECU and harness from a 2001 CL Type S and will probably try to get it running with that for starters. I am researching ways people have made the AT ECU think the transmission is there (to keep it out of limp mode), but so far all I have found is companies that charge $500+ and don't really tell you what they do. Unless I can figure out how to make the changes myself, I will probably end up going to an AEM pretty quickly.

Rupert wrote: I'm confused! Why would anyone want to put a V anything motor in a Miata? You already have a sweet DOHC inline motor that has a ton of potential. Why don't you use that as the basis of your hot build? It's not like there aren't tons of alternatives out there. Cubic inches are great if you're pulling a huge tractor or semi rig or even a boat. My twin 502s were very handy on my 45' boat. But they are much less an advantage when propelling a 2,300 lbs. car Other than a V-12, there is no sweeter sounding or driving V-motor that I know of than a typical inline motor, OK an inline three isn't sweat, but that's not what we are talking about here. That's certainly not typical. And you can actually access and work on your inline motor without an engine removal or other serious cure to obtain access! Please don't even insult your Miata with yet another sbc, sbf, or even Honda installation! From the factory, the Miata motor with all it's potential is already better than those!

I think maybe you might want to stay away from this thread. It's obviously not to your taste. You're making a lot of assumptions that aren't true about things like engine access. Check out the inherent balance of various engine configurations as well, you'll find out there's a reason that larger inline fours need balance shafts but a V6 and V8 never do.

I am so doing this at some point.

Just want more info and completed swaps to work any bugs out.

Titus your car looks great. Good luck on the swap.

This is sad but every time I drive our Odyssey right now I think of how great an engine it is.

Keith Tanner wrote: Check out the inherent balance of various engine configurations as well, you'll find out there's a reason that larger inline fours need balance shafts but a V6 and V8 never do.

Actually, V6s benefit a lot from a pair of balance shafts (IIRC the Honda J engines don't have them, but the older C engines do). Cross-plane V8s don't need them.