[Business]

Considering that somewhere between a ¼ and ½ million of these engines are produced a year, at the very least, it would be a horrible business decision to make them cost much more than that.

But that is also the best strength for it, we can feed off of other markets and very easily find parts. I have absolutely no regrets with this engine. *hugs*

I do, however, look forward to future posts and threads as I'm currently not in the position to get started on the work I have planned but will be working towards attainable goals in the coming months and (unfortunately) years.

 

[KCV6]

Valve stem seals are now all out. This was actually harder than I would normally expect. Most Valve stem seals clip over the end of the valve guide on the cam side of the head and can be pulled off easily with long nose pliers with tape around the outer face of the pliers. This prevents damage to the bucket bores as the seal lets go and comes off. The valve stem seals in these heads go all the way to a machined face in the head and have a large diameter skirt. They require a lot of force to get them to let go of the valve guide and if great care isn't used you can scratch the bucket bore with the skirt edge.

Once again this will all be clear with a bunch of photos that I will put in a new post.

I finished making up all the SST's (special service tools) for setting the timing during re-assembly. It is a shame the cam timing is taken off the end of inlet cam. If it wasn't the inlet could be set with a couple of degrees of advance improving the bottom end and midrange power as the sprockets are not keyed. This allows you to set the cam to cam and crank to cam relationship to whatever you want, providing there is no interference issue with the valve to piston face (nasty interference motor). I suspect if I advance it the ECU will just get pissed off.

Cheers.... Mark

 

[KCV6]

Head is all done. Valves are lapped in, inlet ports are cleaned up around the valve seats, exhaust ports are cleaned up and opened out and it's wearing a nice new set of valve stem seals. I've worked out why the valve stem seals are so different with the skirts. They don't run a hardened lower valve seat, the pissy mild steel skirt is it. This is another in a long line of cost saving measures they undertook when developing this motor. It is cheaper to outsource 1 cheap part and assemble only one part than have a valve stem seal and separate valve spring seat, guesses they will next go the Morris route and incorporate the gearbox into the sump.

Cheers... Mark

 

[brandiniman]

This is so damn entertaining. You don't happen to have a plan to do an after dyno?

 

[KCV6]

No, no dyno runs for this motor, it is a daily driver as this will become my wifes car in 3 months when I get my new car (model undetermined yet), the second motor I will take more time and probably change over to more aftermarket internals. I do believe just by matching the inlet ports to the inlet valve seats and cleaning up the exhaust port edges at the port face the motor will pull a few more ponies. Lots of people go overboard on the port and polish bit especially considering these ports are large and free flowing any way. Opening up the exhaust port internals does very little for gains. Much the same goes for the inlet ports. the trick is to smooth out and clean up the areas closest to the inlet valve. This is always the biggest restriction.

Personally I don't like the "controlled break" connecting rods used in the bottom end even though it is supposedly a good way to make con rods and end caps. For those that aren't sure what I mean, the con rod and it's end cap are cast and machined as one piece. They then introduce a controlled fracture accross the horizontal quadrants (sides of the big end hole) where the two pieces would normally join if they were machied as separate pieces. They then snap them so you get your 2 parts. These snapped edges are not touched so they supposedly are a perfect matching pair. Being cast the snapped faces are about as smooth as a piece of 80 grit sand paper. Where my original No.1 spun and chewed out the bearing seat in the big end, there are small pieces missing on the rough snapped edge. Did this cause the dammage, who knows.

I realize this re-build post sounds mostly like a bitch about the poor quality of components and it indeed is, I would rather pay $1000 bux more for a new car and get a motor that can be "zoom zoomed" day in day out without fear of it breaking because I chose to extend the service interval by an extra few thousand Kms. I am doing with this "sort of blueprint" what should have been done in the first place from the factory.

Anyway enough of my bitching, I better go clean up the second timing cover. Gonna do it and the original aluminium cam cover a nice pale silver gold epoxy 2 pac and re-plate some of the fasteners. May as well make it look pretty before it goes back in. Might look nice in moss green pearl over black. I have no life and refurbish automotive parts as a hobby. A couple of bits I'm doing for my brother Mk2 cooper S....

 

[brandiniman]

FK me that's beautiful. Great work man!

 

[KCV6]

Timing cover done. Nice to see the replacement front main seal is actually a propper seal if you get it from Mazda now. Actually most of the parts you get from Mazda as service spares and replacements are "the real deal". Also nice to know after a chat with my friendly Mazda Spares man they are more than happy to order in any replacement parts if I put a list together and am willing to wait a few weeks as their standard stock order. This means I get them at trade and incur no freight charges. Also oversize bearings in .25 and .5 are available as standard parts.

Anyway a pretty pic of my timing cover straight after paint. It was shot with black epoxy eurathene primer and baked. The gold is a custom mix I do for wheels and cam covers, much like the pale brembo gold (not the darker one).

 

[KCV6]

pics of exhaust port clean up. This was a case of removing the port face sharp edges and blending the port out to match the smallest diameter of the exhaust manifold. with the exhaust manifold I ground the internal welds out to be the same diameter as the modded exhaust port face openings in the pic. Not ideal, but still less steps and bumps so velocity should be marginally improved hopefully improving gass scavenging from the combustion chamber.

 

[KCV6]

Pics of inlet mods. Once again just mild blending of any internal mismatches in seats and ports and a clean up of all the sharp edges on the port face and the petroof head around the valves. Also note the nicely lapped seat face where it mates with the nicely lapped valve face. This alone when re-building a head makes for a huge improvement as it increases compression as the valves when closed now seal 100%.

 

[KCV6]

Finally just a pic showing the cleaned up webbing in the cam side of the head. My pet hate is daggy castings not cleaned up. I removed a shit load of waste material from around the holes in the webbing for where the head bolts go through. Just be real carefull not to slip and damage any important faces like the cam journals and bucket bores. Once all the grinding is complete you need to thouroughly de-grease and flush the hell out of the head in hot soapy water. Now High pressure hose it off getting well into the oil and coolant galleries to ensure you have got all the swarf out. This should be repeated several times and the head dried and blown out with compressed air. Lightly oil any steel items to prevent corrosion. Any swarf is going to ruin your day when the motor is fired up. Finally re-fit new valve stem seals. Green are inlet and grey are exhaust. This colour coding is prety much universal. see how the skirt on the seal at the bottom is actually the valve spring lower seat. In my opinion.... dodgy as it is mild steel zinc plated and not a hardened steel washer, but hey I'm old school.

 

[KCV6]

HAHAHAHAHA... lets start picking on the bottom end. No baffle so you get windage during cornering. I believe volkswagen solved crank windage back in the forties :sarc: . I guess Mazord/forzda decided the Germans were wrong for some strange reason. I hear the 09 gen2 mazda is coming with square stone wheels :yesnod:. 2 bolt mains from what I can see so far.... my god even hyundai wouldn't do this, well ok they might but they don't have the audacity to tag their cars as "Zoom Zoom". Smallest con rods known to man kind which are a complete throw away when something goes wrong as they can't be machined and sleeved due to their cost saving controlled break method of manufacture, on the up side they managed to make a nice crank, oh hang on it's not keyed so it's a POS cost cutter as well. Oh look a sump full of swarf, but thats ok it's pre filter so it must be acceptable. :sarc:

The ultimate upgrade for the Duratech is to replace it with a SR20DET, it would have to be easier.

Mark

 

[pray4mojo]

QUOTE (KCV6 @ Dec 30 2008, 04:50 AM) index.php?act=findpost&pid=1496644

The ultimate upgrade for the Duratech is to replace it with a SR20DET, it would have to be easier.

Mark[/b]

agreed.

 

[MrTea]

nice write up along the way, pictures look great!



and for what it's worth, it's Duratec (no h)

 

[KCV6]

LOL but there is a "h" in biatch. For some strange reason in aus most call it duratech.... go figure.

Motor number 2 is all back together however the bottom end is untouched as it has stuff all k's on it. I'll let my wife break it. Once the car is back up and running I'll do the bottom end writeup on Motor number 1 with a complete strip and re-build.

cheers... Mark

 

[fgpalmer71]

An "h" in biatch! Ha! LOL. Thanks for posting this Mark, I will be very interested to see how much power your work will net. Wish it could be dyno'd, hell I bet half the people around the globe wish the same thing. We love our "horsies" over here.

 

[KCV6]

As much as I bitch about it and long for "the good ol days", the motor is sound and can defiantely be squeezed for more NA ponies. It just worries me that to get more power from head and inlet mods alone will just bring closer the inevitable bottom end crunch. Even Mazda are now admiting to me that spun bearings is starting to be a not uncommon thing. I'm looking forward to stripping the block. It certainly isn't a complicated block by any means, very few parts. Fingers crossed the mains are chunky enough to hold up. Someone will be getting a nice 2.3L at the end of all this. LOL I'm going 2.5 next I guess.

On a side note..... Wow talk about needing muscles in ya S%^t to get that last 20 degrees of talk to yield on the crank bolt. PMSL. Next time I'll mount the motor in the engine stand, doing it propped ona pillow and blocks is no fun.

Cheers.... Mark

 

[KCV6]

All done, all running, dead quiet and very stock.

I won't comment on weather there are power gains other than to say it naturally goes a lot harder, but this is to be expected simply by the fact the valves were lapped and the 5 years of carbon build up gone and the bottom end is near new. Now it's major service time for the 626 and my brothers project Mk II Cooper S needs a lot of parts re furbished.

I'll get back to the second 2.3L re-build once I've cleared my workshop of the other stuff.

Cheers... Mark

 

[obteene]

Wowwow....You are the best.

 

[KCV6]

OK after a week of driving I can provide some semi useful info.

Car definately has more mid range. This could just be a timing thing as oposed to better flow through the head.

First known run for fuel consumption comparison. 58Km travelled to work. Pre re-build was always between 8.4 and 8.7 Litres per 100K's has run 7.7L per 100K's two consecutive times now. This run is a mix of open freeway and city driving. Same route every time with same right foot input.

Cheers... Mark

 

[hokman]

QUOTE (KCV6 @ Jan 11 2009, 02:49 PM) index.php?act=findpost&pid=1502642

OK after a week of driving I can provide some semi useful info.

Car definately has more mid range. This could just be a timing thing as oposed to better flow through the head.

First known run for fuel consumption comparison. 58Km travelled to work. Pre re-build was always between 8.4 and 8.7 Litres per 100K's has run 7.7L per 100K's two consecutive times now. This run is a mix of open freeway and city driving. Same route every time with same right foot input.

Cheers... Mark[/b]

You are the best. I guess the only way for a mere mortal like me to rid of all the nasty cheap costcuts on the mazda 2.3 engine is to get a cosworth engine for 10k.