Kimball

[Ice88]

Hi Guys,

Around a month ago now I got a phone call from cookie, he'd spotted this clean MX5 at a local car club (Seven of Clubs - All Jap Day). So jumped in my car and drove down there

Car was pretty clean, has massive amounts of overspray which is unfortunate, but the car looks really good for its age. No obvious dings, new soft top and drove well. Around a week later I was the proud owner of a stock MX5.

The car is a 1991 Australian delivered MX5 with 235k on the clock, original engine, even came with racing rims . Plan is to swap a engine build I completed for another car into the mx5 with a few extra additions. Details regarding engine build below.

Old Car:

[Ice88]

In 2013 I started the ambitious project of getting decent naturally aspirated power figures out of a FS-DE engine. Most people I'm sure have heard the adage that, there's no replacement for displacement. Which is an old saying that really comes from a time before we had dynamic heads with VVL and VVT.

The reality is that the only replacement for displacement is either the addition of a turbo or revs. In stock form the FS-DE represents a stroker FP (1.8 litre engine), which makes a good naturally aspirated contender. In order to make the two litre FS engine mazda took a FP increased the stroke and altered the deck height of the block.

In effect creating a 1.8 with a stroker crank. Problem is that in combination with the short rods, the rod ratio was abysmal. In conjunction with weak stock rods, the engine wouldn't survive at rpms required to make good power. The engine quite literally would fall apart around the 7400rpm mark due to the forces at that rpm.

To resolve these issues, some ambitious work was required. As a result I purchased 3SGTE rods and pistons that someone else had already purchased, but never had the funding to continue his build. The added benefit (which i don't believe was fully realised) was the benefit of being a bit over 3mm longer then the stock rods. Hence the custom pistons with the wrist pin offset, however I don't believe the original owner had the rods measured so much as used on hand figures to buy pistons. Or there was a slight mistake with the order, as the end result was this:


Quite flush no? Final figures worked out at around 12.46:1 IIRC so 1.46 higher then the calculated 11:1.

Other then snapping a head bolt due to being provided the wrong bolts (the box had the right number, just the bolts inside weren't):


Me in the background, researching for alternates to heli coils. Unfortunately none was found, so the engine had to go back to the machine shop to have new threads added. While there they fitted and torqued the head down for me. Just prior to the head bolt incident:



Head Bolt:


Picture of the fittings and Peterson Pressure Release Valve used in conjunction with my customised oil pump:


Common issue with FS/FP is that sustained high rpm, is fraught with oil cavitation and air rating due to the internal pressure release valve. So had my pump modified to remove the internal pressure release, also had the pump coated to decrease the tolerances and thus generate better pressure

I have more pics etc but heres the final mod list:
Custom Weisco ~12:1 Pistons with 21mm wristpin.
3SGTE Rods
3SGTE Oversized Bearings
Modified Crank to Suit Bearings (i.e. tighter tolerances all round) + Achieve thicker bearings.
Modified Head - 5 Angle Valve Job, Blending, Ported and Knife-Edged Intake Ports, Ported and Knife-Edged Exhaust Ports.
Twiggy Cams
Adaptronic e440D
DocB Racing Oil Pump
Peterson Pressure Release Valve
Modified MBSP for Oil Return
Oil Filter Relocation Kit:
- Works Engineering Oil Adapters
- Aeroflow AN10 Fittings All Round
- Aeroflow Black Tubing
Focus Adjustable Cam Gears
Jay Racing Thermal Spacers
MSP Oil Cooler
Stant Low Temperature Thermostat
Fidanza Flywheel - 7.5lb
Custom NPC 760kg Clutch

[Ice88]

Week into ownership and the old CD player had to go, it was an old item from the early 2000's. So quick trip to the local autobahn and I walked away with a new Pioneer unit. Sounds much better, only issue is I ran out of time to replace the speakers with the Pioneer items that I had pulled out of my old blue car.

I had also purchased a radio surround from omgpham, that comes with 3 holes for gauges in preparation for the rebuilt engine. It was quite tight, and unfortunately the only photo I have:


Some double sided tape will hopefully fix the issue. Ill have to take some more photos of the install, as I said I was working against the clock to get it all done. its winter here so sun goes down super quick, and had more troubles running the cables down the sides of the car then I thought I would.

Did however find and document the following items:


The trunk release with. Which doesn't work, think it may have something to do with this:


No need to worry about shorts or soldering :/

And also:


That ball action. Pretty sure there is meant to be two gaskets/seals between the gearbox shifter and the cabin. So going to need to buy some new ones.

[Ice88]

Had the help of two good friends to remove the engine, with there help we were able to remove the engine and transmission in an hour! Solid work.



Racing mags, check out the chrome:


Unfortunately one piece exhaust and header bolts that refused to budge meant the exhaust had to be chopped. Luckily one of my friends had brought his work truck so, busted out the portable grinder:


And its out:


Looks like the main seal is a little leaky. Looks to be a long nose too:


Just need to sort out the transmission, because the car is using an engine that never came with the vehicle the miata bell housing won't bolt up. Further, differing clutches might require different throw out bearings. So more research ahead!

[Ice88]

So ended up buying a E2200 box from the gold coast. Was searching for one that was cheap enough that it didn't break the bank and that meant i didn't feel bad throwing away the back half of the box.

Randomly was searching one day and found one on the gold coast. Was good, didn't pay too much for it either, with the help of my house mate we separated the box and bolted it up to the race engine:


The wing bolts and two top bolts bolted up, the rest didn't. So off to the fabricator it went to have two more holes granted on the bottom half and two wholes drilled. End result plenty of box attached to block

Some shots:
Comes pretty close to fouling on the water neck!


Was able to get away with using stock FS clutch and Flywheel, B2200 throw out bearing, b2200 slave and clutch fork:


Shot down the box showing how well everything lines up:


Just hope that the output shaft penetrates far enough into the clutch and that I have good clutch engagement etc.

[Ice88]

I mentioned I think previously that the fabricator has been stuffed around a bit by the previous customer, with changing his mind etc. So while I wait there are a couple of things I can do to progress the build, one of which is do the maths for my custom header. Unfortunately as the FS never came in a RWD platform a custom sump is needed, also because of this I need a custom exhaust header. At first i was hoping to use a BP item such a maruha VP, with a different flange plate but the FS port spacing is different on the exhaust side, but the same on the intake. Unfortunate to say the least.

Hopefully I've done the maths correct, in the event that this crazy experiment works below are photos of my equations. If anyone wants to double check my work then that is welcome too

First we need to work out when the exhaust opens BDC, here I'm using the 0.050" lash figures as thats what I had on hand. This is then used to find the length of the Primary Length or in the case of a tri-y/4-2-1 the length of the primary + secondary. I have used a figure of 7200 in this as I don't want this figure to be too close to my max rpm. At present it sits at 7700, with a figure of 7200 the header should stop flowing around 500-600 rpm later:


Then for the secondary we need to work out what length we want the secondary to be, unfortunately theres no real way that I know of to calculate the optimum secondary length, Graham Bell states that you want the primary to be at least 15 inches. Given that from memory the secondary benefits the higher RPM, i wanted to make mine shorter to provide a kick as high as possible.


Calculating the diameter of the primaries.


Seconardies:


In the end I went with 1.75 inch to 2.25 inch primary collector, 2.25 to 2.5 inch secondary. Turns out I could have ordered 1 7/8 inch to 2.25 or such. But based on the knowledge I have, going slightly smaller is not an issue in comparison to going bigger. So heres hoping?

[Ice88]

Got my collectors the other day, they look so smexi. Look one hundred times better in person but here are some quick snaps I took, when I dropped them off at the fabricators:

Primary:





Secondary:

[Ice88]

Living and being around so many 323 people I have access to a lot of BP gear, hence being able to work out port spacing for the exhaust. The intake side has the exact same port spacing as seen here:



The difference being the bolt locations. As such I had someone in the states fabricate an intake manifold adapter to go between a BP and a FS:



Everything looks to be right and normal, until you realise the he has the BP manifold holds drilled incorrectly:


Note that the BP bolt pattern has the two holes at the top for cylinder 1, one at the bottom, which means you have the following issue:


Which means that the manifold would point downwards, in the opposite direction of the intake tract. Which means the manifold would need to be flipped 180. If i wanted to flip sh*t I'd have used a FS-ZE manifold and flipped it. Annoyed.

Means that I need to either have another adapter plate made or pursue other means. (I was hoping to use this in conjunction with a set of Jenvey's)

Also my new Fuel Pump arrived this week:


Just need to get a new fuel filter. Forgot that theres the external filter after the tank.

[Ice88]

I'm a little saddened at the rate of progress at the fabricators, but its coming along. Here are some photos from a week ago that I've finally uploaded.

Engine in the car, oil pan girdle off. Shows plenty of room in comparison to an FE around the subframe:


More in focus shot:


Still a bit of room between the valve cover and the bonnet which is nice too:




Photo showing the angle of the ports and what straight shot from number 4 is like:




In other news I found my charger finally for my DLSR so can start taking photos in something other then phone quality which is nice.

[Ice88]

My intake manifold and throttle body finally arrived, here are some shots of the manifold from yesterday. The manifold is a Skunk2 Ultra Street.

This is what the fs gasket looks like overlayed on the manifold:

Notice how much bigger the B18 ports are? No wonder the feckers make so much hp n/a.

Shot showing what the spacing and bolt hole patterns are like:


Heres what it looks like mounted in the car:


And this is where it all kinda goes sideways rather quickly, notice how high the manifold sits in the bay? due to the massive angle on the intake ports the B18 manifold sits so high that the front fouls on the bonnet.

At first I thought that it'd be an easy fix, machine the flange flat as the flange has extra angle applied. But yeah no, that won't work either.

Shots from some other angles:



Managed to cycle camera battery a few times in the charger, so that now works, yay! The throttle body just arrived this morning so will take some happy snaps tonight maybe after i get home from helping a friend.

[Ice88]

So still not sure what I will end up doing regarding the B18 intake. The head port having such built in angle is a PITA. Building in a wedge is potentially the easiest versus chopping and adding in angle to the runners, but it adds length to the runner and its pretty bleeding tight already.

So not sure.

In the mean time there has been great progress on my mx5. Firstly some sexy headers:



Chopped and welded water pipe to alter the direction the water exist:



Custom Sump:

[ScratchNSniff]

WOW Kris!!! Making some Killer Progress so far...how I did not see this before I have no idea!!!

[Ice88]

Thanks man.

Whole intake thing is driving me mad. Just want to get the intake sorted

[Demon I Am]

Fantastic build!

[Sean5294]

Looking good!