In other words, gobs of torque at idle.

-Ryan

 

yup, that's what i'm thinking.

 

Yay! We can run the AC compressor! (jk)

 

Yep, to your little heart's content!

Hey, the C7R has A/C and the drivers at Le Mans were praising it...

 

the thing i like about this is there's only about 10.5% drivetrain loss on the hp side, and ~8% on the torque curve. most of the time you have to figure 15-20% drivetrain loss and what v8r's curve is showing about half of that loss. nothing but win all the way around.

 

20 ft lb dip at 2000rpm makes the engine totally worthless.
-every m.net supercharger guy

 

This thread is winning.

 

This is pretty awesome! With that much torque down-low, I am surprised they have such a low 1st gear!!!

 

200tq off idle is pretty sweet.

 

<p></p><p>Burnouts&nbsp;<img alt="" src="https://www.miataturbo.net/images/smilies/skid.gif" style="height:72px; width:40px" title="" /></p>

 

More like 4000lb Camaros...

 

<p>Damn.</p><p>&nbsp;</p><p>So in the end, how will this cost compare with a V8 swap?</p><p>&nbsp;</p><p>What's the weight of an LFX w/o accessories VS a LS3? I seem to remember the LS3 is like 370 I believe without accessories. More displacement, but 75% fewer cams.</p>

 

345lb according to gmauthority.com but that doesn't specify with or without accessories. Transmission is also significantly lighter than the T56

 

Both questions that I can't fully answer yet, but intend to.

Of course you can add up the prices for the assorted swap bits from V8R and get a fairly accurate ballpark for what the junkyard parts will run you with a little research, but this never gives the full picture of what it really costs to make the thing a finished, polished, fully operating thing. I'll be keeping an accurate, public tab on the costs that go into this project. Some of the items on the list won't be mandatory for the next guy doing the swap (more complicated cooling system and exhaust for example) but an itemized tab will enable those following along to add up what they would need, omit what they may not, and get a "real" idea of what to budget.

I plan to do the same thing with weights, noting everything that goes on or comes off, including scaling the car in race trim just before we start tearing it apart and then again when it is finished.

I have the majority of the parts at this point. I'll get to work on that tab tonight for the parts already acquired.

-Ryan

 

So I can't let my dad be faster than me.

My 94 Begi S4, MS3, 265hp@12psi has made me pretty happy, but I'm pretty sure the LFX would beat it. Especially after I discovered my valve seats were machined too thin. So after I complete his LFX swap I'm building an LS3. And I'm keeping spreadsheets.

Right now his build is $9775, and it's almost complete. The only big ticket item is going to be an exhaust fab at enthuzacar, otherwise it's just fluids and AN fittings.

I've been gathering parts - but I'm taking my time, looking for deals, while I complete his. But my total is $8072 and I'm still lacking a T56 (~2k), Differential kit (~2k), Engine accessories (~800), Differential (~400), ECU, wiring, fluids, sensors, etc. My LS3 is an L92 with 40k fitted with DoD delete and LS3 heads, but I only paid $2,800 for that versus a crate engine (6.8k with accessories). And this is without buying GM's LS3 controller kit ($1100) which includes ECU, pedal, and harness - I'm going with a stock harness ($250) and modifying it.

Any way you slice it - the LFX is cheaper.

Either way - I'm expecting to have about 16k in my build (and being thrifty about it), and I expect my dads will be done for 11k.

Labor-wise, the only major difference between the two builds is the transmission tunnel modification necessary to fit the T56 bellhousing.

As the saying goes, speed costs money: how fast can you afford to go?

I'm gonna be pissed if I end up liking his LFX's power delivery more than my LS3.

 

Anyone know how this falls into NASA TT? TT3 would be a perfect fit but I don't know how they handle the tubular subframe. The rules say factory subframe is required but I know I've seen V8 swapped miatas in TT1-3.

 

you're right, it's shameful that gm let that happen. shameful.

 

If you have a tubular sub frame the car is now classified as a "Non-production vehicle" and you take a power to weight penalty for it. Penalty is -0.4lbs/HP for TT1 and TT2 and -0.7lbs/HP for TT3.

This also means that the production vehicle modification factors don't apply to you which are:

4-door Sedan or 5-door Wagon +0.2
Modification of OEM roof line/shape -0.3
Modification of floor pan or rocker panel for side exit exhaust clearance -0.2
TT-3 Only: Non-OEM Aero -0.4

 

That was the only solution I could see too but I wasn't sure if Greg was giving specific allowances on a per swap basis. So roughly an 80lb penalty for a TT3 miata that's already planning to run aero.

 

Put together the spreadsheet where I'll be keeping a tab on the costs that go into this. Actual costs once they're incurred will be the important part, but I've also included other main items that I know will be needed with estimates for them:

ThePass' LFX Swap Budget