Engine
Contents
Solo Rules
Engine block must be the same make as the car (Mazda), with some technicalities about cross-make stuff (we could use a ford probe motor since it's the same thing as the 323). Aside from that, everything's virtually unrestricted.
Rev Limit
Starting with 8000 RPMs. The internals I used are probably good to nearly 9000 RPMs, but I don't think we're going to make any power up there on stock cams anyway, so there isn't much point. Fuji Racing revved to 9k on a stock motor for a while and it took a while to blow up.
1.8 Conversion Notes/Parts
Flyin Miata makes a 1.8 conversion kit for 194$ that looks like it will make our lives a little easier. They have a good writeup of the conversion process as well. It turns out that I'm going to use basically none of the kit except the motor mounts, since I did all the rewiring already. Oh well.
Make sure to use a 94-97 alternator. The 99 alternator doesn't have an internal regulator and will totally hose the NA electrical system.
Build Sheet
I've stored some Other Builds for reference.
The motor started life as a stock smoking 99 motor from Panic Motorsports. It was then fully rebuilt with the following:
Block:
- 2002 Oil Pan
- 2002 Oil Pan Support Plate
- 2002 Oil Pump
- 949 Racing Rods
- Wiseco Coated Pistons
- ACL Main Bearings
- ACL Rod Bearings
- ARP Head Studs
- ARP Main Studs (218-5401)
Head:
The full rotating assembly was also balanced, without the clutch/flywheel, and then clutch/flywheel were balanced on the crank against themselves.
Head Gasket
Using a stock 99 head gasket for now, since I did the coolant re-route.
Intake Manifold
Corky Bell made a custom manifold with an integrated supercharger mount, which I heavily modified to work with the Lysholm unit.
Other Options:
- BEGi 99-05 - Only for big power/boost, 539$
- Flyin Miata Old Ubercharger Manifolds - Could be interesting to hack up for a new custom install - 250$
- RP Racing - Makes a bunch of custom manifolds
Fuel
Solo Rules
16.1.D.3 allows basically everything. Open fuel lines, pump, filter, pressure regulator. Cool can allowed (up to 1 gallon).
Injectors
Injector dynamics 725cc injectors from 949, running at 50psi base for around 770cc. From our last tune, we're at ~93% duty cycle at redline.
Fuel Pressure Regulator
Has a SARD adjustable FPR, set to 50psi base right now.
Fuel Pump
I originally ran a Walbro 255HP, but switched to a Deutchwerks 300 pump since they seem to be more reliable and quieter.
Fuel Filter
Replaced 3/22/12 with a new stock filter.
Induction
Pre-Supercharger
Ordered a tight radius 3" aluminum donut to fab an intake path with. Ideally aiming to head down into the area next to the motor to pull fresh air from under the car. Right now, I'm using a 10$ cheapo filter crammed onto the back of the SC.
Supercharger
On the car is currently a Lysholm 1600AX. It was about 2300$ all in. It has a listed maximum pressure ratio of 2.2:1, and we're seeing a max of 19psi with the current setup. The compressor map is available for it. It's currently making ~330rwhp.
If we need to upgrade, I'm interested in the Whipple W100AX, which came out in Sept 2011. Blueprints are available for mocking up a test unit. The unit is 2150$ (had to call and ask) and the direct drive snout option is 140$ (Drive snout options). It seems to be about a 10% power bump at the same boost levels due to increased efficiency, and should be a direct bolt on replacement for the 1600AX.
We're going to be flowing ~650-700 CFM of air, for reference.
SC Pulley
3.125" pulley from the guys I got the head unit from.
Crank Pulley
From FFS: "We can supply 105-130mm 6 rib crank pulleys in 5mm steps, then 140mm and 150mm. $125 each."
Currently using their 140mm pulley.
Remember in the future that the crank bolt doesn't pass through it, so you have to install the SC pulley after the main pulley is on the car.
Tensioner
Using a Gates #38103, which is a 6-rib auto tensioner. It's available at Napa, but on Amazon is much cheaper.
Belt
Found a 6-rib belt that just barely fits on (but requires forcing it over the crank pulley) from Napa, part # 25-060445. "Belt Angle: 40 Deg, Belt Top Width: .807" (20 mm), Outside Circumference (in): 45.187, Outside Circumference (mm): 1148 mm".
Intercooler
Ended up buying a CXRacing RX-7 side-mount intercooler. The dimensions work out really well, but the unit is 12 lbs, which is less ideal.
Fan
I have a cheap fan on the intercooler hooked up via switch from the cabin control panel, but the flow doesn't seem to be great, so I should probably figure out another fan type to use...
Ignition
Spark Plugs
Starting with NGK R5671A-7 (heat range 7, no-resistor race plugs), which FM recommends for high boost applications. They suggest stock gap (0.030) so I'm starting there.
Also trying NGK BKR7EIX (iridium IX), which seemed to make no difference, so I'm just keeping them as spares if I get misfires at an event.
Coil
Using 1ZZ COPs, with the wiring harness modified to do sequential ignition. More info here for the COP conversion I based this off.
Alternator
We need to use a 94-97 alternator on the 99 block with the 1.6 body. The 99 alternator will blow out the electrical system because it has no voltage regulator built in.
- Stock 94-97 alternator: 10 lbs
- Pegasus Mini Alternator: 6 lbs, 280$, requires fab
- More Tiny Alternators: Down to 5.68 lbs, pricing unknown
Don Nimi suggests looking at the Suzuki Spring/Pontiac Firefly alternators.
Clutch/PP/Flywheel
Currently Have: Spec Stage 3+ (SZ453F) clutch kit, and Fidanza Flywheel (both balanced).
Weights (measured by me):
- Fidanza Flywheel: 9.2 lbs
- Pressure Plate: 8.9 lbs
- Clutch Disc: 5.0 lbs
- Total: 23.1 lbs
949 Racing has a multiplate setup. Emilio suggests the twin plate organic, which would be 14.0 lbs.
Other Flywheels (and list weights):
- Stock 1.6: 17.6 lbs
- Stock 1.8: 19.0 lbs
- Flyin Miata - 295$, 10.3 lbs
- Spec SZ81A - 381$, 9.5 lbs
- Fidanza - 355$, 8.0 lbs
JSC has a good overview of all the options as well.
Motor Mounts
I was using the stock 1.8 mounts with the mazdacomp stiffer rubber mounts. However, there was still a ton of engine slop, so I upgraded to the AWR mounts, and though the car is now suitable for vibrating gravel mines, it no longer has any engine slop.
- FM 1.8 conversion mounts + mazdacomp stiff mounts: 6.38 lbs total
- AWR mounts: 6.28 lbs total, 225$
Header
Using the off the shelf Racing Beat 99 Header (ceramic coated by Performance Coatings) for now. Seems to be making plenty of power. It's a 4-1 with 1.7" primaries and a 2.375" outlet.
Called Prather Racing about a custom header, they forwarded me to his son, Jesse Prather, 785-249-0284. He makes a couple different headers, but for wide powerband he doesn't suggest his biggest one. His is a 4-1, 1.75" primaries, 2.5" collector, and it makes a bunch of power over the RB header in NA applications. He doesn't know if it will help a lot on S/C applications. 900$ for the header. Not too bad at all, really. If the RB can't make the power I need, can get this for stage 2.
Exhaust
Chase Race made a custom 3" stainless exhaust with a 5" (Magnaflow?) resonator, and then a pretty small Borla muffler out back. Simple, a couple pounds lighter than stock, and not that expensive.
Other recommendations:
- I emailed Emilio (949) about what to do for an exhaust with the RB header and he says: I'd suggest custom 2.5" or 2.75". Gonna be insanely loud. big resonator and a really big muffler out back.
- Prather Racing suggests doing a 3".
Cooling System
Radiator
Ended up getting a CXRacing 3-row (2.5" thick) 92-00 civic radiator. Fits nicely side by side with the intercooler. Weighed 6 lbs dry.
- Stock 1.8 Rad: 4.5 lbs dry, 1500 cc capacity = 3.2 lbs of water = 7.7 lbs total
Re-Route
Did the hot side coolant reroute to leave room for the supercharger setup on the cold side using the BEGi kit backwards like this guy describes.
M-tuned also makes a kit sold by 949, but it's cold side only and non-symmetrical.
Radiator Fan
Using the stock radiator fan on the new radiator (fits like perfectly, but could probably use some tape around the edge to shroud it). Seems to be holding everything perfectly cool.
Thermostat
The re-route came with a quoted 185 thermostat, but the engine seems to sit around 180 degrees with it. Probably not ideal, but changing it back there is going to be a total pain, so avoiding doing so at present...
Heater
We need to keep the heater fully intact.
Solo Rules
16.1.A. All Stock, Street Touring, and Street Prepared category modifications are authorized. Except as noted by these rules and the referenced rules, vehicles must be as originally delivered including all road-going components such as lights, wipers, interior, heater, etc.
Water Pump
Stock. Don Nimi says that there may be some small benefit to going electric, but the complexity probably makes it not worth it, especially if we can make all the power we need on the mechanical pump.