Roda

This cracks me up...

jakeordie

I noticed they updated the FAQ on their website.

turbofan

iTrader: (1)

Taking an NB with PS and A/C, then in the end having a J car without PS and AC?

I still just don't get the point. I truly don't understand why one would go with these V6 swaps--J or LFX--instead of an LS V8.

concealer404

iTrader: (3)

Price, and a penchant for mediocrity.

(Though honestly, the LFX somewhat intrigues me.)

turbofan

iTrader: (1)

Sure the LFX swap is cool. But by the time you get the whole drivetrain and CTS rear, what are you saving? You're buying the same parts, are you not? Subframe, mounts, rear diff, engine and trans.

I can hear the cost argument for the J I guess, the engine is much cheaper.

Full_Tilt_Boogie

iTrader: (1)

I think the LFX would be cool because it may be short enough to allow a turbo or two in there, and you know the engine/trans could take it.

Nothing makes sense about a J swap. Nothing.
There is nothing spectacular about the engine. Even if there was a cheap, strong transmission behind it, the power potential is not impressive.

concealer404

iTrader: (3)

You're saving weight. Weight is what you're saving.

People are using the T56 behind the LFX? That seems like overkill.

The engine isn't the biggest cost of any of these swaps. The J-swap's real budget darling aspect comes from using a stock trans, driveshaft, and rear end.

Voltwings

Weight and balance. As cool as it would be, my miata doesnt "need" 400 whp to be competitive at a few of our local tracks. Quite contrary, i feel it would be putting me at a slight disadvantage if anything.

Roda

LFX motor and trans can be had for around, or less than the cost of a used T-56, so it is quite a bit cheaper than an LS swap. Also, less firewall fab. If you just want a fun street/HPDE car, and are OK with 300hp with stock reliability, it's a viable option. Easier on tires and brake pads as well.

Sparetire

Bingo.

LSXs require the whole damned driveline to be changed. Its more cost and more work. Stupid T-56 and TR60606 prices are stupid. Looking at what you pay and what you get, a used C5 starts looking good.

K swaps, J swaps, and Turbo/Supers let you keep the stock driveline (as compromised as it is). And that's cheaper. The K swap is probably about the same cost as a DIY-as-**** LSX with a lot less fab. And you get a lower weight than the LSX. And really quality components. Probably a ton easier to work on in the engine bay too. Your spring rates don't need to be fuxored with much either.

But, your still putting more into the swap than you put into the car.

So the search for the Unicorn cheap path to 300WHP continues for low-ball low-brow schmuks like me.

I honestly suspect that in the end its going to be a Rotrex kit and fueling parts. 5.5Kish for 300WHP, not counting clutch, wheels/tires, torsen, 6 speed, etc.

concealer404

iTrader: (3)

I'd say Rotrex is the cheapest and reasonably reliable path to 300whp as well.

Well... the cheapest and reasonably reliable one that makes SENSE, at least. I could put an F2T in a miata and make 300whp for quite a bit less, but nobody actually wants to drive an F2T powered Miata.

Roda

Plus a long block that can take it...

Don't get me wrong, if I stick with a Miata motor, it will be a 1.8 Rotrex. But you're still looking at $7-8k on the low end to do it right.

I like the LFX a lot, but I'd like to see a few complete swaps running for a while to get some feedback before I take the leap.

concealer404

iTrader: (3)

I thought we established that a 300whp Rotrex setup on a stock BP might hold together because the torque will be low and come on nicely.

Roda

I guess it depends on whether 'might' is the level of reliability you're looking for...

turbofan

iTrader: (1)

^this.

might hold together, but for track use? Not likely, not long term.

concealer404

iTrader: (3)

I like to live dangerously.

Sparetire

I've had a semi-fubared 6 speed sitting on top of a slightly fubared refrigerator in my garage for nearly a year now. Why not a slightly fubared shortblock too? if stock goes boom, I have the other built and ready to go.

But that's a really good point: once you start building a BP and spending 4K on a SC kit, damn, its time to take a look at a K swap. Maybe it has less power, but 8K+ RPM is pretty damned fun. Because you're not going to get into a shortblock and just do rods and pistons, you will give in and do boundary pump, etc. Suddenly you just spent another 2K easy. On an engine that's basically a 1980s refugee. It'd be semi-custom, but Rotrexed K24s make lower-LSX power levels.

Its never simple.

Roda

I've actually come full circle and am looking at Ford smallblocks again. 350hp is easy, parts are cheap and everywhere (including T-5s). With aluminum heads, you're only giving up ~20-30lbs to an LSx, and you make that back in the transmission. MS has plug/play for the Ford harness. And they sound better than the LSx...

I'm a little biased, 'cause I drag raced a Fox Mustang back in the day (waaay back, actually), so I know the motors/transmissions.

But this is all getting pretty far off-topic of the J swap... just be happy that there are lots of options if you want 300+hp in a Miata. Too bad they're all about $10k by the time you have a reliable, track ready package...

Leafy

iTrader: (1)

Damn, its too bad no one makes a mount kit for the MZR/Duratec. The NC2 2.0 and the 2.5 all can make 300+ safely. The 2.5s start at about $350 in the junk yard, and theres a t5 bellhousing that fits the motor.

Sparetire

The truth is that the NC will end up being the 'easy big power' of all the generations. Which sucks, because its way below an NB for me and jurys out on the ND save for the ***-end looking kinda terrible.