Miata LFX Swap (Singular Motorsports & Good-Win Racing)
#81
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
ThePass' LFX Swap Budget
#85
I've been sucked into this escapade as well. Check out the MV7 transmission next to a 5 speed Miata. While they look about the same, the MV7 feels like it weighs 35lbs more (have not scaled them yet).
If I recall correctly, with the MV7 gear ratio mated to a Getrag 3.23, gear-limited top speed at 7200 rpm's is 210mph.
If I recall correctly, with the MV7 gear ratio mated to a Getrag 3.23, gear-limited top speed at 7200 rpm's is 210mph.
#86
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Yeahhh that is why I went with the 3.42, and will still be on the look-out for a 3.72.
3.23 is for the salt flats
You were right when we spoke a couple weeks back though - the motor has the torque, so the longer gearing might make for a no-drama 3rd gear-only lap on tight tracks.. looking forward to experimenting.
My MV7 has been living the life of luxury on a pallet up till now. I'll put it on the shipping scale tomorrow.
-Ryan
3.23 is for the salt flats
You were right when we spoke a couple weeks back though - the motor has the torque, so the longer gearing might make for a no-drama 3rd gear-only lap on tight tracks.. looking forward to experimenting.
My MV7 has been living the life of luxury on a pallet up till now. I'll put it on the shipping scale tomorrow.
-Ryan
#88
Top speed is still 168mph with a 3.9, and 80mph cruise is only 3400rpm. I'm really liking the looks of this swap with a stock mazda 3.9 diff and the 949 big-pawr-spec Giken that I already have sitting in the garage. According to the 3 different builds I've seen, I think I could do the whole swap for somewhere between $6k and $7k after deleting the Getrag diff stuff from the list and then selling my 99 engine, 6 speed, miataroadster shifter, lightweight clutch, and megasquirt. That's pretty damn tempting.
#90
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It is do-able, sure (isn't everything). The PPF is normally removed for the swap, which the factory Miata differential relies on. To retain the diff you would need to address a new mounting solution, and get a custom driveshaft made.
-Ryan
-Ryan
#94
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I was going to put my current motor/turbo/cooling system up for sale in the next week or so, but a local customer jumped all over it. I'm rather satisfied that it's staying local. Took me 4+ years, many many hours, and many revisions to get the turbo to run dead reliable at the track.
(old pic)
-Ryan
(old pic)
-Ryan
Last edited by ThePass; 07-17-2015 at 06:37 PM.
#98
So it looks like there are lots of options for the Miata.
turbo
Rotrex
stroker
K24
SR20DET
Rotary
V8 (LS and Ford)
V6 Honda
V6 (GM) LFX
all others (add here)
I was looking for a new mill for the next Catfish, and it really is a difficult decision. However, the LFX seems to check all the boxes:
--can be installed to be as light or lighter than stock Miata block
--stock 290whp, 330whp with E85, 450whp turbo'd (WOW!)
--stock ECU, with tune, or with aftermarket options
--TORQUE. horsepower sells cars, TORQUE wins races (Carrol Shelby)
--relatively simple job, with all the required parts available from V8R
--mass centralization
--bulletproof, robust parts
--relatively cheap parts
--long gears
One of the surprises wtih the Catfish is that with some good horsepower pushing 1,700lbs, shorter gearing is the last thing you want. It always seems like first and second get you through the intersection only, so these new gear ratios should really help the car stretch its legs.
I'm REALLY excited to see how this build progresses.
turbo
Rotrex
stroker
K24
SR20DET
Rotary
V8 (LS and Ford)
V6 Honda
V6 (GM) LFX
all others (add here)
I was looking for a new mill for the next Catfish, and it really is a difficult decision. However, the LFX seems to check all the boxes:
--can be installed to be as light or lighter than stock Miata block
--stock 290whp, 330whp with E85, 450whp turbo'd (WOW!)
--stock ECU, with tune, or with aftermarket options
--TORQUE. horsepower sells cars, TORQUE wins races (Carrol Shelby)
--relatively simple job, with all the required parts available from V8R
--mass centralization
--bulletproof, robust parts
--relatively cheap parts
--long gears
One of the surprises wtih the Catfish is that with some good horsepower pushing 1,700lbs, shorter gearing is the last thing you want. It always seems like first and second get you through the intersection only, so these new gear ratios should really help the car stretch its legs.
I'm REALLY excited to see how this build progresses.
Last edited by cordycord; 07-18-2015 at 12:11 AM.
#100
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<br />FTFY.
<br />
<br />And Rick, I have been thinking that as well. OEM does not necessarily mean track ready. Maybe we will find that it eats cams or valves or timing chains with sustained >5k RPM operation.