Installshield's NA Build

Installshield 2

Gothenburg Superiority
After 11 years of owning my 2002 P5 since new, i guess its finally time to have one spot with all the info on an ongoing build. I've been on this place for almost too long, and still remain one of only a few to stubbornly stick to naturally aspirated power from the FS. I can't say its an easy engine to ring out, but its far better than a lot of people make it out to be. For the most part, i'll stick to whats on the immediate table...but a quick recap of what happened first.

Back in college I had an engineering design class that gave me access to some machining and drafting equipment. Our project was to design and machine something out of aluminum billet. Long story short, i drew up some longer connecting rods and custom HC pistons in a number of different design programs...and cut them out. I later was pretty much given a junked FS that some friends and I tore apart, and put this combo in. With a set of custom cams (worked directly with twilightprotege on the specs, which later became 'twiggys') and a good 1000 rpm higher rev was consistently making around 175 to 180whp...But then life happened. I knew nothing of wiring or tuning a standalone (had only borrowed a motec for the testing, and we made a reversable loom in minutes just to get it running), was reaching the end of school...and needed to put money in other places. I slowly fell off the scene for a while, and never got around to finishing that project...

until now, at least sort of. I'm giving up on that 2.0L design in favor of a more realistic way to make NA power. The ridiculous compression, still very high piston acceleration, and peaky nature of the cams made the car only fun in the very limits of its rev range...below 5500 rpm, it was barely driveable...granted, it was never fully street tuned, but i'm also not thrilled with the strength of the i've learned a lot since i cut those out.

There will be plenty of time to fully detail what i'll do for the 'next' engine. Basically to keep it short; I'm going to go with a 1.8L FP crankshaft...connecting rods of a yet to be determined longer length, over bore the cylinders, and a target static CR of around 12:1. I've been working with Wiseco lately on the rods and pistons. The pistons will be easy according to them, after reviewing the engineering designs i've made, but they usually don't do a single order of custom long we'll see, as i've had some help from members around here on possible factory rods from other engines that will nearly bolt right in...and be exactly what i need.

This setup will reduce displacement down to around a 1.9L depending on the bore, and be capable 8,000 rpm...perfectly reliably...but more on all that later...(been changing some of this lately, after playing with the cams i'd like to use...mechanically i can get 9,000+ rpm easily, but breathing with limited lift up there is going to take some major changes)

The current state of the car is:

Black 2002 Protege 5 w/o ABS, moonroof, side curtain airbags ~156,000 miles haha. Small amount of rust on rear fender needing addressed, burns almost no oil, and remains in pretty good shape...all things considered.

MP3 ecu
NA Twiggy cam shafts
FocusMSP cam gears
custom mid-pipe with stock catalyst
Racing Beat cat-back
RR-racing UDP
AWR 94a 'front/rear' mounts, MSP timing belt mount, stock gearbox mount
elm 327 bluetooth data transmitter used w/ Torque Pro for Android

New Tein SS coil overs
urethane front control arm bushings
17x8 +48 Enkei RS+M wheels (15.2lbs each according to my scale)
Bridgestone RE760 Sports 205/45

Kartboy shifter bushings
stock shifter extension removed, using a momo set screw 'ghost' knob right now...with matching leather boot
gloss black interior trim
Alpine 9835 receiver, alpine speakers, 10" sub in ported box (probably coming out soon), and a rockford amp that i don't even remember haha
DaveB gauge rings

For the most part, the car has been this way for a few years, other than the wheels, coil overs, and ecu.

Stuff ready for immediate install:
VTCS delete coming with the install
Speedhut custom 52mm Oil pressure, oil temp, and analog clock. (i'm making a custom bezel to put these in the DIN slot above my receiver)
Fidanza 7.5Lb flywheel
Exedy stage 1 clutch
various interior shat that wore out; have a new gear knob, boot, and napa leather steering wheel wrap replacement on order.

I'll be buying a members Microtech LT10 hopefully next month...and then will source the crank, a used block, possibly a used head...and really get to work.

Nothing too exciting yet, but as it warms up a little outside this will start moving.

A random pic with the old Rota D2's, before the Tein coil overs (pic is with S-techs, both items will be for sale soon...very cheap!!) This was for a friend looking to buy them, but they wouldn't fit his car, so i'll get more 'actual' car photos soon.

The Twiggy's and gears

comparison to the Twiggy intake cam with a FS-ZE intake cam (little dark, but you can sort of see how much of a difference in duration these have)

the gauges, i'll have more for these once installed. They were made to match the factory lighting at night. Check out Great prices and they'll do custom overlays and logos if you want. You also pick nearly any color needle, type of font, color of back overlay, type of bezel, etc...for no charge...

I'll have a lot more up to date pics of the car as soon as its not...2 degrees out there...and anyone interested in some parts (ZE cams, Rota D2 wheels, 2 5Zigen FNO1RCs, misc stock parts, etc.) let me know, i've been too lazy to make a FS thread...but have a good bit of stuff i can let go for cheap.
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Pursuit of HP happiness
02' Protege ES
Can't wait to hear it.

Plans for intake and exhaust manifolds? Just did a quick reread of the 197.6hp thread and you were using modified off the shelf manifolds.
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Installshield 2

Gothenburg Superiority
Tweety, out of boredom (its very slow this time of year at work, so i sit here in front of a computer haha) I'll make a couple of 'tech article' type things to put in here, one of which i'll start in a few minutes. I'll go over all that kind of stuff.

makemegofast...I'm going to use a ported factory DE intake manifold with with VTCS delete to start, see how it drives. I would love to eventually go with ITBs, but won't even bother considering that until i get the standalone and learn how to use it...Let alone get the engine itself built up.

That last engine, honestly i barely remember what i had...I should go read that too haha...For the brake dyno tests with the engine on a stand, we used an AWR header coupled into a big silencer, and a length of hose to simply get it out of the lab...the lab had a universal fuel cylinder with a programmable pump, a coolant heat exchanger, and the entire system (which we mounted sensors to the engine) was controlled by a Motec M800 (a $6500+ standalone...)...For that nearly 200hp figure, there was literally nothing other than a stock crank pulley turning a water pump with a small belt, and a flywheel with the brake dyno clamped on it...The motec controlled everything electrical, so the engine wasn't even turning an alternator...

it only went in the car for a month or two...and i used that AWR header (a friend had it from a wrecked MP3, which is what the engine came from including the VTCS'less IM) with a Racing Beat exhaust w/ cat-less test pipe...I later sold the header to buy the JDM mazdaspeed 4-2-1 i have now, which i'll keep using for this build.

and Orion, how do you like the twiggys? I'm installing mine this weekend for break in...I do have gears to go with them, but i'll only have the MP3 ecu to work with for the timing being.
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Installshield 2

Gothenburg Superiority
#1 Torque and HP explained: (i'll keep these tech things numbered, so if you see this and don't want to go through a wall of text...skip it haha)

One thing i wanted to do years ago was make a thread like this, but add a bunch of technical stuff to help anyone interested understand the fundamentals of natural aspiration. It'll be wordy, so feel free to skip it if you like...but one thing this forum never really had was an easy place to find even basic information on performance engine design. A lot of this, also, won't be strictly NA...many principles apply to an engine overall, regardless of it utilizes forced induction. To keep it specific though, this is ONLY going to be about piston oriented 4 cylinder engines rotary mechanics, or higher cylinder designs as it won't really be relevant to this build.

I'll start off with the very basics: Displacement, revs, and Torque vs. HP...more specifically; how you can make more of it.

Torque and Horsepower are commonly misunderstood. As the two basic measurements for an engine's particular output, its not surprising. Like gravity being one of the very first 'forces' you become aware of; its often the hardest to explain...and therefor understand.

The best way to start is to simply ignore Horsepower for now. Torque (think of it as twist) is really all an engine does. It twists a shaft that turns a plate that is connected to another plate that then turns another shaft that turns some gears, some axles, and some wheels with rubber wrapped around them. The more force generating that twist, the higher the measured output...the more mass the engine is capable of moving...and more importantly for us; the faster it can accelerate that mass...

The fun starts though with how the engine makes that torque. Unfortunately, it doesn't just keep making more and more torque. It reaches a threshold at which it makes the most torque, then begins to drop off. This is because of a lot of reasons that i'll discuss later on, but for now, just consider that because an engine creates a 'curve' of torque...and because the technology to create a gearbox that constantly and infinitely adjusts gearing ratios (to keep accelerating at a fixed engine speed) isn't really here yet...a particular engine has to have a couple of gears bolted to it so it can be usable over a large range of road speeds...

before applying horsepower...the basic principle of torque is directly related with an engine's displacement (the size of its cylinders)...We've all heard 'there is no replacement for displacement', and everything else being equal...the more 'size' to the cylinders, or the more cylinders there are...the more torque the engine can create...that isn't 'free' torque though, the size allows more oxygen to enter the cylinders, and more gasoline to be pumped into them...resulting in the higher torque output...

but luckily, an equally important...yet more confusing output...can be derived from torque: Horsepower...

Horsepower formulas and where its applied can be all over the place, and even used in electrical stuff...and rather than going over all that, lets just apply it to our application:

HP = Torque * RPM/5252

A very simple formula that quickly shows a lot of different things about an internal combustion engine. The constant (5252) allows the formula to be used across a broad range of things that 'twist' stuff. To put it as simple as possible, Horsepower is the result of making as much torque as you can, but also at an extremely high speed. So, unlike torque, which will go all over the place and is a measurement of how hard an engine is twisting its can make a constant amount of torque, or even begin to lose some, but as long as the rpm of the engine is climbing faster than the rate at which the torque is dropping'll continue building horsepower.

That constant also makes one broad detail applied to any automotive engine. Because of the way HP is cannot...under any circumstances make more HP than torque below 5252 rpm...or make more Torque than HP above 5252 rpm...if you ever want to call out a 'fake' dyno, look at 5252 on the chart...if the two curves don't intersect there, some one is full of shit...

so horsepower, basically, is making a little bit of a high rpm...and that is how it relates to other measurements of 'power'. The advantage of horsepower is simply when you apply this small amount of torque to fast moving parts, you get many of the same effects that you do from large amounts of torque at lower speeds...even better though, Horsepower usually covers a broader rev range...and only builds and builds until you reach the mechanical limits of the engine...that isn't always the case, but its the very foundation of this build entirely.

I'm not increasing displacement, i'm actually going to lose around 100 cc's...I'm only using ambient air pressure (which gives me 14.7 psi at most) the only thing left for me to revs. For reasons beyond the scope of this, you obviously run out of room with increases to displacement...that automatically means you have to increase the mass of the engine to make room for that empty space, as well as to handle it...and also the movement of the parts needed to utilize that bigger space...mass and overly high amounts of piston movement are actually the psycho ex girlfriends of revs...they hate each other...and its the real secret to making a good bit of horsepower from a relatively small engine.

later on, i'll get into the two ways to have displacement...and how they apply to this build...
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Installshield 2

Gothenburg Superiority
#2 Reciprocating Assembly Geometry:

In this one i'll go over basic geometry of an engine's bottom end, which includes how variables like bore and stroke factor into an engine's behavior. Later, i'll get into details on the cylinder head and its components.

The bottom end, or 'reciprocating assembly', refers to a particular engine's main power making components. This is where fuel and oxygen content of ambient air is mixed and burned in a controlled as possible fashion to make the torque and hp output discussed earlier. Understanding how these mechanical parts work together is critical for designing or creating any type of performance upgrade.

An engine's displacement comes from 3 things. The number of cylinders, the diameter of the cylinders, and the stroke of the cylinders. The measured stroke is NOT how deep the cylinders actually are, but the length of piston movement within them. Cylinder wise, and engine can be one of 3 things physically. It can be under-square (a stock FS-DE engine), which has less bore than stroke. Square; bore and stroke are of equal measurements. Or over-square; More bore than stroke. for multiple reasons, most small displacement 4 cylinder engines are under-square...or right around square...but very rarely significantly over-square...

Stroke is arguably the more critical measurement of the two...Stroke factors directly into some important geometry with the assembly that bore simply does not. Changing stroke will always change this geometry, where as changing bore will have no effect on the angles that the connecting rods/pistons interact with the crankshaft...Bore isn't irrelevant, but it takes larger adjustments to make noticeable differences in engine behavior than it does stroke...I know that is confusing; increasing bore will basically increase output at any given range, but only by a small would take a very large increase in bore to make very noticeable increases in output...and given that in a small inline engine, you simply don't have a lot of room between the cylinders to begin this engine's case, increasing bore isn't really a realistic place to make more output...Also, stroke is derived from the crankshaft itself, bore is not...and since the crankshaft is exactly whats outputting all the stuff the engine makes, its really the one to worry about first...

but stroke...we have PLENTY of stuff to throw around...the FS-DE in 3rd gen proteges is effectively a 'stroker' to begin with. Its a 1.8L FP-DE engine with stroke increased from 92mm (bore between the two is 83mm)...Since stroke is actually factored by the radius of the crank shaft arms, the two engines have a different crankshaft. The FS engine also utilizes a taller block to make up the 7mm extra stroke...those are really the only differences between the two engines.

So right away you could be thinking 'why would you want to remove displacement from an engine that is already so small?'...This is exactly where things really get complicated...

One variable for an engine is directly attached to stroke...something known as MPS, or Mean Piston Speed. Thats just a nerdy way to talk about the average speed of piston through a complete 4 stroke cycle, and is simply stroke x rpm...the more stroke you have, the higher that average speed is going to be for any given rpm...a lot of stroke gives perfect piston speeds for 'breathing' at lower rpm. Any naturally aspirated engine will reach something known as 'maximum volumetric efficiency' at some certain rpm. Max VE will ALWAYS happen at the point where the engine makes its maximum amount of torque. At that particular moment, the pistons are traveling at a perfect speed to pull in as much air (by vacuum, scavenging, charge velocity, etc.) as possible during its intake stroke...the computer then applies the perfect amount of fuel (hopefully, anyway) for that amount of air...and the most powerful expansion stroke is obtained...

With that in mind...more stroke makes slower turning crankshafts move pistons the crank isn't spinning all that fast, but the pistons are moving at the right speed to hit a sweet spot...and max torque happens there...

but after max VE, problems the crank is spinning faster and faster, and the piston speeds are climbing with it...and that efficiency will decline because of it...the faster moving piston cycles are happening too fast to pull in as much air as they did before, and torque output will decline...If you read higher up, you remember that horsepower will start to come in to play with this, though. The goal for the build is always centered around torque, but utilizing small amounts of torque at high speed to make higher one way to make more horsepower, is to move that max volumetric efficiency number higher up in the rev range...and reducing stroke...does exactly that...

so by reducing stroke, you change the rpm at which the pistons are moving at the right speed for the best breathing...keeping other things equal, reducing mean piston speed will increase the rpm location that max ve occurs...and if you can carry that torque curve over 5252 rpm better than before, you're immediately netting higher horsepower output...without changing anything else...obviously its not quite that simple, but that explains one of the advantages of the FP crank for this build...
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Installshield 2

Gothenburg Superiority
#2 contd

So now that stroke changes and the effects are known, there is another equally important aspect of stroke...and particularly, how the length of a connecting rod comes in to all this.

Any given piston oriented engine has something known as a connecting rod ratio. That ratio is the length of the connecting rods (center of big end to center of little end) in relation to stroke...the FS-DE has 135mm connecting rods, and 92mm of stroke. The rod ratio is Rod Length/Stroke, which gives a ratio of ~1.47. The FP-DE has 129.2mm connecting rods with a stroke of 85mm, giving a ratio of 1.52. Those numbers are not very far apart, but its a very significant difference. Rod ratios range from low 1.4 to only mid 1.7 or so for most production 4 cylinder engines, with anything above 1.65 getting very rare anymore.

The rod ratio is used to correlate piston acceleration, and for a lot reasons...the math with this gets pretty messy and equally confusing, so i'm just going to skip it for now. Piston acceleration factors in to how quickly a piston reaches the top or bottom of its stroke, how long it 'dwells' there, and how long it takes to leave...These acceleration figures factor into where the engine reaches max ve, similar to MPS (they are closely related)...But while mean piston speed is only used as a general measurement for an engine, piston acceleration is actually the more important piece of its a more precise measurement of the stress these parts are under...high piston acceleration is what will quickly destroy an engine, at least at specific locations...The 'messy' part of acceleration is that it'll be increased at certain thresholds, and decreased at without a bunch of math being thrown around, we can just say longer rods are 'better' for lowering acceleration in areas that we want it lowered...

The lower the rod ratio, the higher the piston acceleration at reaching and leaving TDC...and the less amount of piston dwell time, in degrees, a piston sits at top dead center...for obvious reasons, a low rod ratio is not ideal for high rpm...and therefor high horsepower...The dwell time is also an important aspect for tuning principles like ignition timing and fuel requirements, as well as cam shaft overlap...

So to increase the rod ratio for better higher end power and simply increase the length of the rods.

Thats the biggest aspect of this build. I'm attacking the rod ratio from both directions in order to increase it (longer rods and less stroke) Using a FP crank in a FS block automatically gives at the very least 7mm extra rod length to work with (just need to source the parts)...but when you factor in running higher compression, location of the wrist pin on the piston skirts, ring location, etc...i'll be able to run even more than thing is certain though, the FP connecting rods will be out the window...They're so short it would take some extremely goofy pistons to make any compression. Even the short FS rods would need some funny pistons too...i'm hoping to run some rods that are 12mm longer than stock, so 147mm total...which yields a ratio of ~1.73...lowering piston acceleration to the point of making 9,000+ rpm not much of an issue...that isn't concrete yet, as i need some measurements of piston to deck level at TDC, which i won't be able to do until i get the new block...

The only other aspect of the assembly to really touch on would be the compression ratio...and that is straight forward and easy...Compression of an engine just means how tightly it squeezes the intake charge...mechanically its simply how close the piston gets to the top of the block deck (where the head and gasket meat the block) at top dead center...the FS stock is 9:1 (at BDC the empty cylinder space is 9 times the size of TDC)...I'm looking to run around 12:1...Squeezing the charge more, makes it push back harder during ignition...since a lot of the compression stroke is utilizing the inertial mass of the spinning assembly, high compression is an easy way to get a bump in output for basically just puts more emphasis on proper tuning of spark and well as gas quality...there is a limit to what streetable compression you can run, and it is directly proportional to how long the pistons dwell...but many production engines run 12:1 or higher stock, with similar rod ratios to what i'll be making...

That pretty much concludes the principles behind the assembly changes...I'll get going on the head tomorrow most likely...
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Installshield 2

Gothenburg Superiority
Head spinning a little. I'll read it again later.
ha no problem man. In the past, especially when the NA side of this car was a little more active...we would get asked the same questions over and over about certain things...the main reason for all that BS is simply so I can link back to it for any newer users that may show up farther along in the build...and it should answer more than they'd want to know...

And again, anyone only interested in eventually seeing a protege with an engine that revs pretty high...can skip all that and it won't matter...its for those interested in the tech behind it...I could think of a lot of things a lot more fun than reading that, so i won't be offended if everyone skips it haha.


Pursuit of HP happiness
02' Protege ES
Top notch info as always.

On a side note I believe it was said that SR20 rods would be a good candidate for longer rods. Not sure of the specs though.

There was A LOT of good info thrown around the N/A race to 100hp/l thread. It's a bit of a task sifting through the off topic posts though.
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Installshield 2

Gothenburg Superiority
^thanks man,

yeah i need to go through that again. The Australian's are tremendously helpful with some of the those internal measurements, and i'm looking into SR20 rods too...I was also informed of rods from a particular Mercedes that may be exactly what i need, but not sure on availability yet...I'll keep digging...

Its a shame we lost Andrew (twilightprotege) through the twiggy thing, he was really pushing the way that all went down, and kind of bittersweet that now i'm holding an unused set of those cams almost 6 years later...


2003.5 MSP

Could you do a tech article on static vs. dynamic compression. It will help explain why going from 9:1 to 12:1 compression ratio is not extreme, especially given your cams and cam gears.

I'll see what I have still have for rod and piston info. I followed a lot of your old posts and was considering swapping an FP crank and sourcing some rods and pistons for my wife's P5. Have you talked to wiseco about getting just the pistons from the FS long rod kit that used to be offered?

I know what you mean about BNIB twiggy's and focus cam gears being bitter sweet.... one day they'll be installed!
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