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Installshield's NA Build

Installshield 2

Gothenburg Superiority
Yeah, I'll do one for differences with compression measurements...and the cylinder head. As this goes on ill probably go back through and clean them up so it's easier to get only the important info. Consider it unedited for now.

And as far as wiseco. I've been talking to an engineer there named Mark, who has been helping with the rods and pistons. So far he is saying pistons will be easy, so whatever I come up with he can cut...they just won't be off the shelf, so I'll have to wait a few weeks for them to be made. It's the rods that are goin to be tough...so I'll really get in to looking at that stuff shortly.

Twiggys are going in tomorrow for a break in period...then pulling the entire engine out and going over everything. Will check valve lifter clearance after break in, and paint the cover plus cut a window for the gears. Will do the vtcs delete and port match, water pump, new timing belt, clutch and flywheel, etc.

Ill take a lot of pictures during the install, try to have them up tomorrow night or Sunday.
 
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01 MP3, 03 MSP
Nice read I learned a bit from ur posts that's for sure lol. I got a question , since you are gonna go for a higher compression ratio why not use a pistons like the ones in the skyactiv engines since they produce a 14:1 ratio? I'm not sure of the dimensions of the pistons but if they fit Do you think that would be something you could use in your build?

Also could you explain about how the air fuel ratio and the spark play into the whole hp and trq thing ? Would like to learn more about my car and the inner workings
 

Installshield 2

Gothenburg Superiority
^^ as long as people are interested, i'll discuss anything you guys want...All this stuff is basically what i went to college for (BS in mechanical engineering), so its mostly info i'm familiar with.

As far as the Skyactiv engines...Most modern engines now use direct injection, which is a newer type of fuel injection that gives better control over the amount of fuel delivered...and more importantly, how its burned...It uses a far higher pressure pump and lines, different injectors entirely, and some radically high resolution fuel management...

direct injection usually gives the same displacement engine slightly better gas mileage...but also allows the same engine to run some pretty intense compression ratios...The way the fuel is delivered at very high pressure directly into the hot chambers, it instantly aerosolizes (sp?) with the intake charge of air...and gives a very even burn...its also used in conjunction with a computer that can very quickly react to detonation (a common worry of high compression)...

for those reasons...that high of compression isn't likely to be very friendly on our engines...
 
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01 MP3, 03 MSP
Oic so the 12:1 ratio that you are going for would you call it the sweet spot without doing harm to the engine? Also what kind of design of the piston heads are you gonna go for that would get you to that high compression, as in the sky active engines have like a " volcano" kinda shape to add more compression. So of you use that kind of shape would it a good thing or a more simple flat design would be ideal for your engine?

I'm new to all this so the more I can learn the better lol
 

Installshield 2

Gothenburg Superiority
haven't yet determined piston faces...probably won't utilize anything all that exotic, just for expense purposes...but I'll use close to 'race crowns'...which have the upper compression ring not far from the piston face...that is good for expansion, and makes the expanding flame front immediately build up on the piston...and it also leaves room on the skirts for raising the wrist pins, which helps with balancing...

the things i just mentioned, especially the race crowns...are not great for handling detonation though, and detonation is just an uneven or poorly timed flame expansion...which i'll go over soon in a 'chemistry of an engine' thing...

so yeah, you're right...in a way 12:1 is kind of a sweet spot...Increasing the rod ratio also increases piston dwell time...which is great for breathing, but changes requirements on compression (you can't run as much safely, everything else being equal)...as well as ignition timing (you can't advance timing as much with longer dwell times)...So for a 1.73'ish rod ratio, i wouldn't find it fun to babysit the tune for higher compression than that...there would be a lot of factors trying to get the fuel to burn weirdly...it could be done, but not really ideal for driven engine...
 
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01 MP3, 03 MSP
Oic very interesting. So since u said that increasing the bore doesn't really help on these size engines, are you goin to increase the bore on your project block.

Also since you are increasing the compression does it mean that you have to increase how much fuel goes into the cylinder during the intake stroke ( not sure if that's the right wording or not) ?
 

Installshield 2

Gothenburg Superiority
The FS engine itself is actually one of the last production versions of the F series Mazda 4 cylinder designs...There were a few others before the FS, namely the FE...which many regard as one of the very best 4 cylinders Mazda ever made...it just wasn't in very many cars, and was physically very large for such a small displacement...

the S in FS basically meant 'short'...and it makes sense, as the FS is one of the shortest designs around (from the timing belt to bell housing end)...that makes it pretty light and compact, and easily transversely mounted for FWD...but leaves very little room between cylinders for boring..So yeah, as i said in that tech thing...You simply don't have enough room in there to over bore the cylinders for anything other than a marginal difference in output...I'll probably go with a .050" over-bore, which is still within mazda's service limits for the block...and will make up a handful of cc's to counter the reduction to stroke...I'll basically end up with a roughly 1.9L engine when said and done...

I don't want to make bore size irrelevant...its a VERY good thing for certain engines, especially when you multiply that increase across a lot of cylinders...but for inline engines, its usually not a realistic place to start looking for more power...

On the compression side, in terms of fuel requirements...thats tricky, and i'll include that in the chemistry thing i'll do...there is an area of chemistry known as 'stoichiometry', which is related to the ingredients of reactions, the left over byproducts...and more specifically, the balance of reactions...compression does fit in with this, and changes some aspects of the fuel requirements...but not in one easy to understand fashion...high compression can require tons of fuel for cold starts, but then less fuel at rpm ranges that you would think it would need more...its kind of goofy, but we'll get through it...for now, just think of higher compression as needing more attention and more precise control...not necessarily 'more' of anything...
 
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2002 Mazda Protege 5
Sub! There's a lot of good info here, thanks for taking the time to share this with everyone on the site.
 

Installshield 2

Gothenburg Superiority
Installed the Twiggy's and FocusMSP gears on Saturday...everything dropped in perfectly...

Its been a while since i've been in a car with bump like this haha. I'll get some sound or video clips up soon. I wanted to get the cams in and get a few hundred miles on them, then check and adjust valve clearance if its needed...and also finish the valve cover, as i didn't cut a window in it yet...or even replace the cover's gasket, which is definitely needed...

The gears need some attention, adjustment wise, though...It'll start and idle fine...but lifting throttle and letting the revs fall nearly guarantees a stall...these cams have a fixed overlap of 12* at .050" lift...and the stock MP3 computer has a hard time catching the rev decline in time to prevent the stall...when it does catch it, its just bumps at idle perfect...and sounds incredible...but since i don't have much control over idle speed right now, i'll have to dial in that overlap a bit to keep dynamic compression up...its bleeding a lot of pressure off currently...and 4 out of 5 times; i'll lose the idle pulling up to an intersection haha...
 

Installshield 2

Gothenburg Superiority
#3 Cylinder Head

The FS (and FP engine) utilizes a dual overhead cam 16 valve cylinder head...which is pretty common among modern engines, although unlike most current engine lines...this Mazda engine family never used any form of variable valve timing control...The profile of the cam lobes are all you get, and there is nothing controlling them other than a belt connected to the crankshaft...Entirely 'physical' design like this doesn't limit your control as much as you might think, but it will always involve some compromise on how you want the engine to perform...Systems like V-TEC are NOT why a Honda K20 can spin to 9000rpm...its simply why a K20 can spin that high, yet still have a completely quiet and smooth idle...

in our case...we don't have that option...if you want revs...you have to sacrifice some smoothness and torque availability down low...

the way a head works is straight forward...there are 4 valves per cylinder...2 intake, 2 exhaust...2 cam lobes are positioned for each cylinder, per cam...so the intake cam has 8 lobes total, 2 for each cylinder...same for the exhaust...and the lobes are ground as pairs, so that each intake or exhaust valve per cylinder is moved at the same time, duration, and length...basically, it all works in pairs...

This is about as simple as a DOHC head could be...As far as the computer is involved, the only thing it is watching is the position of the exhaust cam (a sensor that reads magnets on the cam shaft's sprocket)...and the position of the crank...by comparing that data as the crankshaft turns, it knows which cylinder is at what position, and therefor when to inject fuel, and when to ignite the mixture...this, commonly, is refered to an engine management system's 'triggering'...

The cams themselves control the valves...and because of that, the specifications of the cam lobes are directly related with how the engine breathes...They are the gate keepers for letting air in, and letting exhaust gas out...and are easily the most complex parts of the entire engine, design wise...small changes to certain specs of a cam can make some really good...or really bad...changes to its performance...The lobes interact with 'tappets' that are mounted onto the valve's stem...the lobe pushed the valves into the chambers. Under the tappets, a retainer and stem lock is in place, that houses valve springs...the springs push the valve back to closed as the cam lobe leaves the tappet surface...head design such as this will have every valve closed when the cam is either not in place, or the lobes are not pushing on the tappets...

For the most part...there are 3 different specs to worry about with a particular pair of cams (there are more, but I'll have a specific cam article soon)...

duration: the amount of time, in rotational degrees, that a cam 'lifts' the valves (usually measured at .050" of lift for comparison to other cams)
lift: The amount of measured distance the valve is physically 'pushed' into the chamber
overlap: The amount of time, in rotational degrees, that the exhaust valve remains open while the intake valve begins to open

As far as modifications to the head itself, it gets pretty limited for the DIY type of guy...Nearly everything, other than assembly or removal of the parts...needs to be done by a proper machine shop...The head has a cast-in series of ports for the intake charge and the exhaust pulses...These ports, in certain cases, can be machined to larger diameters, have angles in them changed or removed, and the surfaces polished...again though, work such as this is pretty much impossible to do accurately yourself...and its very expensive and time consuming to have done correctly...Same with the valves...you can increase the size of the valve seats, and use larger diameter valves...but at a significant cost...for those reasons, this will be one of the very last modifications i look in to...

Modifactions to these areas are actually very complex when it comes to tuning. A streetable engine has to be able to operate effectively in a lot of different speed ranges...It needs to have the flow speed to get a nice gulp of air right off idle to get the car rolling, and has to be unrestrictive enough to breath effectively that high revs i'll be running...Getting all these variables right...isn't easy...bigger cross-sectional area of the ports slows intake charge speed down, which dramatically decreases low end performance...you can even get it so wrong that you can create intake 'reversion', which is where the air will simply stop moving in the correct direction...fouling up the maf readings...and making the car literally inoperable...

With that said, its not something to take lightly...and the LAST thing to do is do these mods before i have the parts in place in other areas to take advantage of it...as in...i'd end up with all of the disadvantages of a free flowing head at idle and low rpm...and couldn't yet take any advantage of the high rpm benefits...

but since the cams are all directly controlling those valves...you can use different cams to change all kinds of things related to the opening and closing of them...

So to quickly go over that (i'll get more specific later on)...you can run cams with more duration to keep the valves opened longer, you can run (very slightly in our case) higher lift on the lobes to open the valves a little bit farther...and you can incorporate some more overlap to have the exhaust cam open just a little longer when the intake valves begin to open...this overlap number will correlate with something know as scavenging, which is where exhaust pulse vacuum in the exhaust system will begin 'pulling' elastic air volume into the chambers...even BEFORE the intake stroke utilizes its own vacuum to move air in...

there will be A LOT of info coming on overlap soon...Now that we have all the physical parts of the engine wrapped up, i can go into further detail about how all this stuff works together...things like dynamic compression, pressure bleed, scavenging by using proper exhaust diameters, intake systems, etc...as well as simple adjustment to cam timing by using adjustable cam gears...
 
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Installshield 2

Gothenburg Superiority
There is already more usefull information in this one thread than the entire Wikipedia database
thanks man, glad you feel that way...

I've only touched the surface with specifics...nearly everything so far has just been 4 cylinder engine related, in general...Hopefully by the end of the week i can have a lot of info on cam timing, as in adjustments one can make on his own with a set of adjustable gears...and start getting info out that is completely relevant to these engines, rather than 'everything'...
 

Installshield 2

Gothenburg Superiority
^^yeah thanks again man, especially with putting up with the journal questions before the purchase...The info you gave let me find the original buyer in a couple of minutes, and everything checked out...

Leaving work now, and will get the valve cover off again to adjust the overlap and check lash tonight...finally warming up around here, so a decent evening to work on this stuff...
 

Installshield 2

Gothenburg Superiority
So I took the valve cover off tonight, check all tappet clearances, and adjusted the gears a little...

I retarded the intake cam 2* and advanced the exhaust 4*...taking 12 degrees of overlap down to 6, roughly...idle was dramatically improved, actually too much imo...and absolutely no stalling now on throttle lift...im probably going to advance the exhaust back another 2*, trying to meet an impossibly awesome idle w/ stalling to a stock like idle...in the middle...not that i'm after just idle, but i'd like to run as much overlap as possible with the stock ecu...as i've already got a pretty competent exhaust system bolted on...which could take great advantage of that...

now the bad news...on the exhaust cam...my quick steel plug had started to back out of the cam shaft end...I followed all directions, had seen some similar things done with it (mostly on motorcycle engines), and allowed enough time for a full cure...but it seems to have not worked...it was pushed out of the cam end about 2mm or so...all in tact, not pieces or anything, and the lip on the air box side of the head prevents it from coming out any further...tonight i was only able to simply press it back in by hand, but thats it for now...that cam needs to come out for some lash adjustments anyway, but i'm reluctant to not get the intake cam out also...and simply plug those things some other way...I felt like it was 'too easy' to begin with, but live and learn...

car will be grounded for a few days until i can figure out the logistics of fixing this, a clutch flywheel install, VTCS removal...etc...all in the next few weekends...
 
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Mazda SP20 sedan (MP3)
So I took the valve cover off tonight, check all tappet clearances, and adjusted the gears a little...

I retarded the intake cam 2* and advanced the exhaust 4*...taking 12 degrees of overlap down to 6, roughly...idle was dramatically improved, actually too much imo...and absolutely no stalling now on throttle lift...im probably going to advance the exhaust back another 2*, trying to meet an impossibly awesome idle w/ stalling to a stock like idle...in the middle...not that i'm after just idle, but i'd like to run as much overlap as possible with the stock ecu...as i've already got a pretty competent exhaust system bolted on...which could take great advantage of that...
I have been wanting to adjust my Twiggy's in order to close the overlap to improve the idle (as I let the stock ecu control the idle rather than the Microtech) and also to get better midrange power. I know which direction to move them but was wondering how much would make a difference. This will provide a nice guide to how much to adjust each cam.

Keep up the good work! :)
 

Installshield 2

Gothenburg Superiority
^^thanks.

If you haven't adjusted it yet, it must be because of US vs. Aus stock computers (for idle, at least)...as we have nearly an identical exhaust system it looks like...I still have the VTCS butterflies in the IM, so i'm sure that can mess it up some...but it would stall more often than not, and even popped a p0300 code just as it stalled at one point...

But like i mentioned, the amount of overlap i closed was pretty heavy...I'll definitely be messing with that more when i re-plug both cams...ideally i'd like to raise the idle 150 or so rpm...as that will definitely allow more overlap...and i know of this phantom procedure using a jumper wire to short some of the diagnostics while you adjust the idle screw.... which makes the ecu not learn around the adjustment. But my manual that illustrates it is for a different FS equipped car (a 626), and the FSM just lists all these different SST's for it...so i'm still digging...

Anyway though, i'll put up my findings with how the engine responds with adjustments...The basics have been posted on here before, but its pretty hard to find...and more importantly its mostly just rehashed stuff from other forums, not changes people made on these specific engines and the results of it...

so far i just stayed safe...most engines are a little more picky about intake cam adjustments, as the intake system is usually a lot more restrictive and complex than the exhaust system...its also fundamentally easier to push air than it is to pull it...so thats why i only went 2* on the intake to start...when closing overlap, you have to remember that the exhaust stroke, and valve closing event, is the FIRST event related to overlap...the opening of the intake valves as the piston approaches TDC of the exhaust stroke...is the SECOND event...

so anything that makes the exhaust valves close sooner (advancing the exhaust timing) or the intake valves open later (retarding the intake cam)...will close overlap in the specific degrees of your adjustment...

and so far we know 6 degrees of overlap (with a 1:2 exhaust bias) is too stock like haha...12 degrees for me at least (no bias) was not streetable...so i'll find something in the middle...
 

Installshield 2

Gothenburg Superiority
Oh and one other note...

2.0t03speed is helping me with this, but if anyone else knows too it would be great info to have...shims...anything you have, i'm all ears...

The twiggy exhaust cam has a changed base circle in order to keep factory spec ramp angles between the lobes and tappets...So the exhaust side lash should be between .020" to .024"...intake side lash can be the same as factory spec (.010" to .014")...

I checked all 16 valves last night...all 8 intake valves are perfect at .012" (kind of crazy after 156,000 miles)...

the exhaust side's 8 exhaust valves are a little tighter than needed though...cylinders 1,2, and 4 are all .018", and cylinder 3 is .017" on both valves...

i've found the 'adjustment disc' part numbers and everything...and it seems they're a dealer only item, which is fine and still relatively easy for me to get...but i don't know what i'm starting with thickness wise...I can't find the factory stock thickness that is currently in there, and i'd rather order this stuff before the cams come out again...I know I need to increase roughly 8 tappets by .002" (2 of them .003") or so...but i don't have the numbers to start...

I'm giving Ryan a call after i get some other work stuff going, and i'll report back what i'm told...but anyone that already knows this; feel free to fire away...can't find it anywhere on the forum...
 
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13 CX5
KJ01-12-599/T=3.550MM
Z502-12-545/T=3.052MM
Z502-12-552/T=3.100MM
Z502-12-558/T=3.148MM
Z502-12-565/T=3.196MM

Stuff like that?
 

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