Mazda 626 Hatch - My Love story/ saga / Build Thread

[ausloki]

This has been posted on a couple of forums now but not everyone visits the others so I thought I'd post it here as well.

I have always liked the 626 Hatch and to date have owned five of them, (pics here) three consecutively at the same time.
Since helping the original MrSpeed (Patrick or Adlorin) put together a supercharger kit for the Probe and testing it first in Australia I kept
building on new ideas and changing my goals.

My end result was my 1995 626 Deluxe Hatch. The deluxe edition came standard with a few extras hat the standard 626 Hatch here in Australia didn't.
Digital Climate Control
Full Leather Interior
My first upgrades consisted on Suspension and braking components as my original goals were always to have a nice looking sleeper so i didn't want the exterior to look much different. I Tried the many different suspension options available for the probe but was never happy with the results. Instead I finally decided I liked the custom feel of the BC Coilover kits with a matching spring combination close to the later released Tein kits. of course knowing i was going boosted i also needed to make sure i could stop safely. This was never going to be a track car but my daily driver, so i didn't need to go fully overboard. The Mazda 6 Breaking system was chosen in the end as it was almost a direct bolt on
but more importantly it looked stock (licensing restrictions can be a biatch sometimes).

If you have a good look you will notice one other big advantage with the coilovers. No nasty perch to rub against the tyres/rims.
hence you can run a wider profile without interference.

The next route was of course some nice rubber that matched the profile of the vehicle and worked well with the suspension. I trialled several 18" setups and for a few years utilised the low profile Pirelli 225/40/ZR18's on a set of 18" Advanti Rims. These looked good and felt good and made sure the car handled like it was on rails. I encountered one minor problem though. every time I went on a cruise and run across poor roads with many potholes or rough surfaces I was continually scratching up the rims (not to mention you felt every bump) and having to spend $$$ fixing the damage.

Eventually I downgraded in size to a 17" Mazda 6 Rim running 235/45/17, this is what I'm still running today and gives a nice stance as well as excellent performance yet doesn't scrub out every time I hit a pothole (no sore butt cheeks now).

(here it is after some more panel work in the shop)


The original motor was of course a KLZE auto with custom exhaust , (ebay headers with a custom catback running 2.5" pipes with redback CAT and muffler). but the auto just had to go. That was the next conversion.

I shopped around for another donor vehicle with an MTX transmission and upon finding it pulled the necessary bits to convert this to manual. The only problem I encountered was the wiring loom. Being the deluxe edition it had far more wiring than the stock vehicles to utilise the digital climate control. So I had to use a 93 loom and dismantle the stock loom to match pin for pin what was needed without the ATX extras. Now that was fun (sarcasm).

This then became my daily driver for a while until my other plans came to fruition. A KLG4 Hybrid supercharged engine.
But until then I simply stuck with a SC KLZE using an Eaton M62 in the AC location.

Fabrication stages of the AC Bracket

The same process but showing the first overdrive Crank Pulley that was CNC'd by MR Speed (Patrick), again a lot of assistance and co-operation from many members
went into the fruition of these projects.

A comparison shot of the OEM 36-1 timing pulley next to the overdrive pulley. This increased
the Eaton's Boost from 4.5psi to 8psi without the IC


Around the same time (2006) a member on Probetalk posted his findings on a new set of custom rods that could increase the longevity of a boosted KL engine. the specs listed below
H-Beam style rods; pretty much the industry standard for cost effective high performance applications
Machined from 4340 chromoly steel forgings
Piston pin bushing left undersized for hand pin fitting
Finish ground on Sunnen cross-grinders
Millenia-S size piston pin bore
Millenia-S/KL size crankshaft end bore
Millenia-S center to center length
Bolts are ARP 8740 series with 12 point heads and have been increased from 8mm diameter to 7/16” diameter (~11mm) to increase the strength of the bolt. The Standard English size also reduced cost of the bolts significantly.

These now are simply known as the "RUROCKN" Rods after the members name on Probetalk and opened up the potential of the KL to many budding enthusiasts
like myself.

and the common comparison shot showing Stock versus Millenia versus the RUROCKN Rod

But once the spare KL03/DE engine was finished with for mockups and fitment, the teardown began.

Then decisions needed to be made, these were a constant flow on affect, obviously with new rods, one needed new pistons.
Many factors need to be considered at this time, such as performance goals and how to achieve what I wanted.
Luckily the pistons decision was made easier by other members through another bulk buy utilising "Diamond Racing" and after a rough start
The final pistons were correctly received.

most pics available here
Engine Build Pics here

 

[ausloki]

Then I Started the block modifications in preparation for rebuild and assembly. This was done by a local machine shop that gave me full access.

Boring of the block to 20 thou oversize.

Notching of the block in preparation for the rods.

And the pic on the right is the final balancing of the crank with pistons. rod weights being calculated.

img-383033-7-9a8aa452e1b72b82cb71d94619bimg-383033-8-d9c8a8083d629f036b8dd68b82a
Crankshaft machining after the initial balance process was calculated. and to the right the beginning of the lube and assembly process

Some quick snaps of the preparation and assembly. The Notching you see in the pic is to allow the rods enough travel from the bottom end up to allow the piston/gudgion pin room to secure the piston
before it can be lowered back into the block. the big ends of the rods will not fit down the bores no matter how hard you try.

A youtube photo album compilation can be viewed Here

 

[ausloki]

From the above picture you can fully understand the need for the notching in the block and how the assembly process must be followed.
Other mods that were made to the block and components in preparation for the build is the oil gallery re-bored on the block and the crank as well.
to this bottom end rebuild the only other change was shimming the oil pump to increase the pressure relief and hence increase the oil flow volume.

The next stage in the build was to consider the heads and the route to follow to help achieve the gains I wanted. For this the original choice was a KLZE set of heads
port matched to a standard IM and changing the valve train to more reliable lightweight components but retain the KLZE/KL31 Cam profiles.

The heads were basically stripped and the valve train components replaced with KLG4 springs and retainers. as well as the valves, and crunch space being highly polished.
The only other mod chosen to reduce overall rotating mass was a set of adjustable cam pulleys. (be aware that the adjustable cam pulleys were not chosen for the adjustment capabilities)

Knowing that the engine was going to be boosted and another weak point might be the stretch to yield head bolts myself and a couple of other members that had purchased the rod/piston combinations looked into the possibility of some ARP head studs. At the time ARP Fasteners were only too happy to do three custom orders but this wasn't good enough for myself. Honda guys had readily available stud kits available for their vehicles why couldn't we.

So In mid 2008 I contacted Chris Brown (Director of Specialty Products) at ARP Fasteners in Santa Paula, CA to investigate what was required to make this possible. Luckily with the thanks to Probetalk and other forums many KL enthusiasts had been in contact for custom orders in the past and they deemed there was enough interest to get the ball rolling so to speak.

The first requirement from ARP was a KL series engine that they could utilise for R & D purposes. A donor engine was obtained and the process begun. This was basically a long process so rather than post the email updates I received on a monthly basis from Chris I'll just say that nine months after the process started the parts were produced in bulk kits and supplied to resellers with a full off the shelf part number. ( A big thank you to ************* for being one of the first to stock these for us)

 

[ausloki]

Pictured above assembling the valve train, lifters and cams

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And that was the first build assembled and pretty with my nice powder coated parts to match.

Having completed this build i started on investigating the electronics aspect for engine management as i figured i could test and prepare everything i needed on the current working
daily driver with the KLZE without risking damage to this build.

The first choice of course was the Megasquirt system as so many others on Probetalk had experience with the product if i needed help or assistance.
So I purchased a couple of MS1 Ver II and then version III kits and even the MS II when it came out.

And installed it into my test vehicle.

and began testing with cro. I new I wanted to go fully synchronous in both spark and fuel eventually so i was already pushing the limitations of the MS1 and that was why i was always
upgrading to the newer versions all the time. I wanted as large as a map as I could build 32x32 ideally with full fuel and spark control. The 36-1 crank from the KLG4 at least gave me the clarity
on trigger points and I just used the Home CID from the stock distributor to give me the 720 degree firing events required for full spark and full control.

 

[ausloki]

But I started with the coilpack from Mazda 626 (KLG4) first for spark control with Millenia S injectors and the Eaton M62 setup first. Following is some more pics of the different testing stages
of this period.

Above is one of the driver circuit boards I made for the coilpack. During the testing of this circuit I burned out a couple of the transistors during road tests. Eventually I traced this back to an intermittant
faulty coil in the coil pack but after the burnouts I revised the circuit to utilise IGN drivers instead as they had built in protection. (More pics to follow on that later)

And a quick video of it running on the coilpacks

 

[ausloki]

Once I had a working MS base map I started using autotune with the wideband to fine tune more of the map whilst I was driving multiple trips. This worked beautifully but I hated having a complete distributor hanging out and not being used just to have a home trigger on the CAM.

So I began purchasing multiple CAS units from different vehicles to find something that closely resembled what I needed and would fit into the stock distributor location.
Thus was born the modified CAS unit from a Miata 1.8L engine.

The above CAS unit was almost perfect. My machining the outside diameter of the cylindrical part until it met the base of the sensor block it gave enough room
for engagement on the CAM and gave me both trigger events for the engine management without the ugly dizzie cap and leads.

As shown above. I simply removed the trigger assemblies from the oem distributor to install into this CAS unit. no issues.

And here is how it sits on the heads on test fitments.

What you cannot see is how it is secured. under the cam covers there is a half shell that is mounted on that end where the distributor normally bolts in. For me I simply rotated the CAS unit until My home signal was where i needed it to be and drilled a countersunk philips screw through this cap and into the CAS unit. The timing never moved after that .
the more diligent of you may also have see from some of these pics that I had already decided to go an alternative route for the ignition. More on that shortly.

 

[ausloki]

The next stage I decided to do was continue on with the ignition aspect. Obviously I had to rebuild my driver circuit to drive six simultaneous coils to go full synchronous but I also decided that
Coil On Plug Would be a nice option as well. So after trialling several COP units I decided on a set of CBR coils and wiring loom from xtremethings.com

Here you can see the COP units and the wiring loom, the only drawback to these were I had to use Marine Plugs as there called. You know how some spark plugs you can screw the
tip off where the high tension lead normally attaches. then this is what you need.

 

[ausloki]

Once again whilst rebuilding My goals changed again. The biggest concern was the KLZE heads. because the heads are fitted with two different size lifters (HLA) a 30mm and a 33mm and the difficulty I came across whilst trying to source the 33mm lifters I knew then that any future rebuild would create this same problem, not to mention the expense. So after a few drinks and a late night in phone calls back and fourth to US and Japanese Suppliers of Lifters I decided my best course was to utilise the more common 30mm lifters. But to do this I had to go back to a standard head...

After further consideration I decided to scrap my CAS setup and go for a KLG4 Head and IM and then I could use the rear cam sensor, not have to port the runners to match and I could save myself some time.
So I purchased a couple of complete top ends (again thanks to Michael aka KLZEPORSCHE) for his assistance in obtaining and shipping some of these items for me.

Let the games begin.

EGR hmm whats that for ?

A bloody ugly waste of time thats what it is!

Lets start cleaning it up... damn this is time consuming.

Vris, who needs that on a boosted engine. Hell we don't need all these mount points in the casting either.

So once it has been cleaned up then the holes are welded and re-sanded before base coat prep. (Next time when funds permit Im going to do a custom Intake design similar to the Honda's I think)

 

[ausloki]

And it seems my folder for the IM is corrupt so All i can give you is a few pics of it complete with the ceramic coating.

i

Did I mention the ceramic coating... All intake and exhaust components were ceramic coated inside and out to attempt possible heat buildup.

The new heads were prepared the same way as the klze heads with one minor exception. I purchased a set of Colt Tri-Flow CAM's for the build as well.

 

[ausloki]

Having Already Purchased what I thought would be my last blower I'd ever need (Rotrex C30-94) I began the mockups for the Intake and exhaust pipe work.
The ebay headers were nice but had limitations on the secondaries as well as the problem of turning the engine bay into a heat soak. My first though was a wrap solution but it looked ugly as
and i was concerned about it trapping moisture. My final solution was to ceramic coat everything first to see if this would work.

Tie up and spot welds in place

Almost finished.

Welding done. Now onto the ceramic coating.

Purty ain't it ?

 

[ausloki]

Then onto the IC and discharge piping. Again more creativity here for mounting both the IC and relocating a power steering cooler as well.

Front shot showing position of IC

Showing clearance behind the bar after modifications to the front radiator support. (yes it will survive a front on collision without the front end collapsing)

Power Steering Cooler in new mock up position, in some of the photos above you can see it under the IC but this left me no room for the blowers oil cooler.

Front Stance with it installed.

 

[ausloki]

One important aspect I forgot to mention earlier. Obviously with boost you must be able to supply the fuel.
All my vehicles I automatically upgrade the fuel pumps to Walbro 255's with new regulators. But of course you need injectors to be upgraded to supply as well.

For my first build I opted to use Mazda RX7 Primary's at 550cc. at the increased fuel pressure of 43.5 psi you get a bit more.

564 CC not bad.

Again going with the Royal theme (purple and Gold)

 

[ausloki]

And the Discharge Piping was basically the same process as the exhaust.

From the blower to the IC and from the IC to the IM with the BPV flange in between.

And then.

Then Ceramic coating and re-installation

 

[xxxmonoxidechil]

Any chance you can edit out the posts and get the pics working? Love seeing some more 626 builds.

 

[ausloki]

After putting down 5k km's on the engine I noticed that I was having issues with heat and large amounts of blowby in the crankcase ventilation system.
We have no definite answers at this time but I discovered the rings supplied at build time were not what I requested. The Engine shop simply installed them anyway and forgot to mention
it to me.

but basically the ring gaps are larger than they should be for a boosted engine and they are standard "high performance" rings not the stainless file to fit I had requested.

At final destruct time the engine was running a Haltech Sport 2000 Engine management system paired with a M&W 16B CDI unit to fire the COP's in full sequential mode.
The M&W CDI unit will shortly be replaced with a newer single wire unit but until the rebuild is completed it will be standing anyway.

The Clutch is a SPEC stage 5 (yes i know , Overkill) but with the amount of $$$ spent it will probably remain so.

Due to financial constraints this build/rebuild is now on hold. Im on a pension (forced) and had to invest the last $$$ i had in getting a daily driver organised for the transport of the wife and kids.
This at least is now finished (except for a rebuild transmission) but is usable until such time as I can get my wife the care she needs and I can return to work.


1) The rings had a huge blowby issue which was only clarified at tear down when we discovered the wrong rings and clearances were used.
2.) Oil Pump (Toga HV) was not infant a high volume but was below specifications.
3.) Due to a faulty check valve on the IM additional crankcase pressure was being applied and aerating the oil

All of these things were contributing to imminent failure so it had to be taken of the road for further analysis and will wait until im working again before the new block is prepared as I wish
and prepped for the newer designs.

For those wanting to see the vids you can see them here

First Start

Dyno Run in time

My Now daily driver until we are back on our feet