I. Overview:


Note the VICS system in place here, just like the BP's.


Good picture of the stout block. Closed deck Iron block, with good meat between the cylinders.


The valvetrain is a direct actuation system, just like the BP and K series DOHC motors. The disty is the same as the BP disty but a slightly longer drive shaft to reach the exhaust cam.

The FE DOHC combustion chamber. Note the nice pent roof design, and the large size of the exhaust valves. Plenty of squish area as well, plus room to clover leaf for NA applications.

FE DOHC Ready for shippment

The FE DOHC throttle body. Note the primary and secondary TB butterflies. This should greatly help low end throttle response, and assuming the diameter of both of them together don't hurt top end performance by being too small, will perform better than one larger diameter TB.

The factory cast exhaust manifold is a great OE piece. Equal length primaries, good sized runners and cast iron for longevity.

Note the similarities between the FE DOHC manifold and the BP DOHC manifold.


Since nobody has gotten to the limits of the FE3 bottom end yet, all we can do is guess. So here is a comparison to one of the top 2.0L, 86x86mm, DOHC 4cyl in the import world: the Nissan SR20DET [the other being the 3SGTE]. FE3 rod/piston on the left, SR20DET on the right. I'll just let the pictures tell their story, but SR20DET's are known to hold upwards of 400bhp on stock internals [pictured].

FE3 vs SR20DET again. As much as I want to write here, I think I'll just let the pictures tell their tale.

FE3 VS SR20DET again. Note the FE3's floating pin versus the SR20DET's pressed pin.



II. Limitations:

A) Normally Aspirated:

Head flow data -

Originally posted by mbeaver (heliumrush) on www.miataforum.com:
Danny (SCCA Racer) and I have spent all day a Polk Performance 501-847-RACE. Flowed FE3 heads, had Don Polk do a Level 3 port job (bowl porting, short-side radius, gasket match, and boss work)on Danny's head. The head still has a factory valve job (with unknown milage), stock valves, and the ported numbers are only the rough cut. Its still a diamond in the rough and expect higher flow numbers when head is completely finished, plus its probably getting oversized stainless valves also.

What I learned today a sheet metal intake manifold is a huge improvement in CFM across the entire lift range.

I also plan to try to have stock 1.8 BP head flowed and I will flow the intake manifold. I am also wanting to try get Polk Performance to make a sheet metal intake manifold for the 1.8 BP heads.

Also FE3 stock head has outflowed most BP ported heads that I have seen.

Well anyway here are the flow numbers.

FE3 Head Flow Numbers
All flow numbers taken at 28 inches of water on a JKM 600 CFM flow bench.

Head is used with unknown mileage, stock valves, and much needing a valve job.

Stock Intake Ports without intake manifold and with radius entry.

Lift in inches CFM
.100 82.64
.150 103.03
.200 135.90
.250 160.13
.300 180.26
.350 188.50
.400 226.48
.450 233.91

Stock Exhaust Ports with test pipe

Lift in inches CFM
.150 106.3
.200 137.15
.250 168.86
.300 186.00
.350 191.00
.400 193.94
.450 193.94

Stock Intake Ports with stock FE3 intake manifold without throttle body.

Lift in inches CFM
.100 61.31
.150 103.03
.200 135.90
.250 160.54
.300 180.94
.350 189.57
.400 193.21
.450 199.32

Stock Intake Ports with custom long runner sheet metal intake manifold without throttle body.

Lift in inches CFM
.100 71.59
.150 104.47
.200 142.05
.250 170.54
.300 193.94
.350 202.57
.400 215.50
.450 222.50

Intake ports, Level 3 head (bowl porting, short-side radius, gasket match, and boss work), without intake manifold and with a radius entry.

Lift in inches CFM
.100 104.3
.150 141.33
.200 174.83
.250 193.94
.300 210.84
.350 226.48
.400 241.11
.450 251.50
.500 254.90

Exhaust ports, Intake ports, Level 3 head (bowl porting, short-side radius, gasket match, and boss work), with test pipe

Lift in inches CFM
.150 104.00
.200 142.60
.250 177.42
.300 202.57
.350 218.80
.400 225.00
.450 230.00

Intake ports, Level 3 head (bowl porting, short-side radius, gasket match, and boss work), with stock intake manifold without throttle body.

Lift in inches CFM
.100 88.7
.150 122.72
.200 151.35
.250 170.54
.300 183.12
.350 190.0
.400 199.0
.450 202.57

Intake ports, Level 3 head (bowl porting, short-side radius, gasket match, and boss work), with custom sheet metal intake manifold without throttle body.

Lift in inches CFM
.100 106.30
.150 145.22
.200 184.05
.250 198.00
.300 215.53
.350 226.48
.400 237.50
.450 241.11
.500 242.50

B) Forced Induction:

1: Jay B's 1G MX-6 FE3 Turbo


Jay B's FE3; 9:1 CR JE pistons, 19psi on a KKK/Garret Hybrid [~20G/T04E size as best I could tell], SDS EFI, 850's, 93 octane with a gallon of 116. As you can tell by the AF curves, he's really rich, so with some more tuning and head work, 500whp on pump gas isn't unrealistic. Note how he keeps on making powar past 6000RPM, where the F2 would be coughing and wheezing with its 12V head and crappy exhaust port design.


2: Danny's FE3 Miata

Bottom of the Intake manifold remains, ready for custom plenum and long torquey runners.


Disty block off plate. Since the FE3 originally came FWD, like the BP it has to have some changes made when switched to RWD. The stock FE3 disty would be in the firewall on a Miata.


Danny chose to run hard coolant lines. It looks much more professional than the ones that he would have had to run with makeshift sections of heater hose from NAPA.


The FE3 is a might bit taller than a BP. The FE block is actually 14mm shorter than a F2 though. So you guys who are thinking about running an 86mm stroke in a Miata with long rods in a F2 block are going to have to get creative with the oil pan [dry sump?]. It'd have a mean rod ratio though [finally NA Miatas could make REAL power]

As you can see, the FE3 isnt too much wider than the BP, but still requires creative mounts to fit.

Test fitting the motor.

With the stock mount points and oil pan, the FE3 sits a bit high.


Almost, but imagine when it torques around under load....


Big plenum for the custom manifold. Looking at that, I'm guessing upwards of 2L for plenum volume: great for high output forced induction with high pressure ratios. I wonder what his boost pressure to exhaust pressure ratio is...

Custom lower passenger's side engine mount.


The whole package.


Since the turbo is so close to the master cylinder, an aluminum heat shield is employed. The OEM Miata turbo needs to employ something like this...


Like the rest of this car, Danny went the professional route with braided lines and custom overflow bottles/catch cans.


Note the cute 9B compressor wheel on the dip stick Very slick.


With a warped head and exhaust leaks, I'd say 370whp and 323 ft/lbs to the wheels isnt too shabby. The motor had a coolant leak at some point, which has since necessitated a rebuild. On the bottle, Danny's shooting for 9's. Hope he can find a drivetrain solution, because at last count he had toasted 3 rear ends and 7 trannies.


Thanks to Danny for the internals pics, and the pics of his Nasty FE3 M1, Thanks to helium rush and Danny for the head flow data, and the FE3 guys from PT for the FE3 pics.


Mazda FE DOHC 2.0L 4cyl