180bhp sounds like a good estimate. I am assuming you mean a 10.7:1 engine right? This number could be achieved with just the pistons and ECU upgrade to an FS-ZE I would think (or at least around that hp number) and then the various bolt ons to help breathing could free up a little mid and higher rpm breathing and power without having to raise rev limiters or anything.

gcs118 about the FS tech at a dealership, I doubt you could find someone with the experience of tuning a FS for more power. You could find someone non ignorant about tolerances and specs, but I doubt anything more (as in a good way to go about tuning your engine) Maybe but probably not...

I think a Haltech is the cheapest device to give you control of some big needed things such as rev limit. I don't think even the more advanced piggybacks such as Unichips and E-Manages will allow you to adjust max revs. It would suck if you built a hard pulling engine that got it's throat slit right when it was starting to have fun...

It is not the best platform for N/A by any means, but 140whp would be much better than a stock FS-DE, and as Carguycw stated, the engine is undersquare and suffers at high rpm. Boring the cylinders to bring it closer to square or maybe over (not sure if this can be done to an FS, can't find the specs right now) would help a little with high rpm breathing, but would still not create a Honda F20A...

 

Sounds pretty good...thanks carguycw and Installshield. Do you guys have any sources online, or books I could get ahold of to learn a lot more about this stuff? I could use a good explanation on boring and stroking and the square stuff and so on. I am learning little by little, and I appreciate all the help you guys here on the board give.

 

I picked up a 93-97 Probe manual a few years ago when i owned a Probe GT. I forget the brand of it but I purchased it at a Pep boys I think. Probes had Mazda engines, the GT model had a KL series V6 and the Se and base had our 2.0L (different ignition system, but that will just complicate this) I would recommend picking one up. Unfortunatly the only manual specific for our cars that I know of is the Mazda Tech Manual and it is really expensive. But the 4cylinder probe has a few similar front suspension sytems and is a good place to learn more about the engine. It has all kinds of specs and measurements. The rest I learned on this forum and from years and years of reading car magazines. Actually the only experience I have actually working on cars was simple maintanance and a clutch change + replacement timing belt on an A3 Jetta. But you can still learn some techniques with out actually doing anything...

As far as engine squareness/Bore/Stroke...

Bore refers to the diameter of a single cylinder. Stroke refers to the distance the piston travels up and down within the cylinder. Oversquare engines have a higer bore diameter than stroke distance. Think of a 19,000 rpm 920hp F1 engine. Oversquare engines in general tend to breathe incredibly well at sky high revs compared to undersquare, but create less torque. In some situations the same engine won't creat even half the amount of torque. Undersquare engines have a smaller bore diameter than stroke distance. Extreme undersquare engines can be found in Firetrucks, dumptrucks etc... Some fire engines can create a mere 110hp with 15 times the torque. It will also redline around 1850 rpm (this example is Diesal, but you get the point). Those two engines mentioned are at the extreme ends basically. Our 2.0L falls slightly undersquare in favor of decent low end torque with a not so pleasant high rpm pull. I still can't find my manual, but I think that you can bore (get them cut to fit larger diameter pistons, +increase the engine displacement) the cylinders enough in an FS to bring it slightly oversquare. This isn't an exact thing, but this could tend to help the engines choke at redline. The FS has other problems though that don't make for a high revving power plant. As Carguycw mentioned the Block design and con rod ratio's don't help, as well as the lack of variable valve timing (V-Tec, VVTL-i, BMW's Double Vanos, Porsche's VarioCam plus,etc.. These help the engine keep good lowend torque with certain cam profiles, then adjust the cam's position in the head to give different profiles and better high end power). Honestly a Turbo is the only practicaly way to get more noticable power +torque. Doing all the latter post N/A mods won't bring the cars torque up much if not at all, which is where the streetability comes in. Depending on the cam profiles you go with you could actually gut the torque altogether. 180hp is great but not if you loose 20lb/ft of torque to get it. Around town you will barely be able to pull the car around. It wouldn't be noticable until the revs are high enough to take advantage of the cam profile. If you are like me and think it is ridiculous to have gobs of power and torque in a car that has the front wheels pull it around (like some dudes with 20+lbs of boost in a FWD Eclipse), get the J-spec cams and maybe some headwork +ECU, then go with a light pressure fast spooling turbo. A small turbo with very little lag will give enough boost to reach around 160whp or more, plus keep the car feeling as close to N/A as possible. Also a company might eventually make a Supercharger which will be the smoothest way to go all together. The power from a supercharger will increase linearly (?) with the engine revs and remain less "peaky" than a high strung N/A engine. Hope some of this helps...

 

I won't quote your last post Installshield , but it CERTAINLY helped and made things much clearer. Thanks for taking the time to explain. Before I ever bought any mods I decided that I would go NA. To me, forced induction is almost like cheating in a sense. I want to learn how everything on my car works, and from there make improvements. I just have A LOT to learn, and I don't think it would be possible without the help from people on the this board especially. As soon as my shop manual arrives at my dealer for me to pick up, I will read it like it's my Bible. Once again, thanks for the explanation, and thanks to everyone who contributes their knowledge!

 

I agree with about its amlost cheating. It is nice to get tons of power with forced induction, but I always respected BMW, even Honda and the newer Ferrari production engines for creating more than 100bhp/litre N/A...And not a problem and you are welcome...

yeah Jesse, I kind of stessed that more than I should of in the above post. I agree that changing the rev limiter is not a big concern, but even the FS-ZE redlines at 7000rpm (and I think the actual limiter is closer to 7250 or a little more, can't remember) Wouln't bumping the limiter up at least a couple hundred RPM's still be beneficial despite all the breathing problems. I am only refering to "after" all the headwork, pistons, ZE intake manifold, varous bolt ons, and at the least the ZE cams (if someone wanted much more than 140whp more aggressive cams will be needed) Ed said that his powerband was bumped up a couple hundred rpm with his low compression ZE, and that it pulled hard all the way to redline (I would bet that Mazda's factory claim of 170 on a true FS-ZE is right about 7000rpm). I don't mean change it to 8,000rpm or more, but just a little higher than the stock 6500. If someone wants the most power they can safely get N/A, I would think that it would need to be a little higher, but I could be wrong...

 

I've driven Ed's car, and it DOES pull hard all the way to redline; the powerband feels about the same as an 1.8L FP-equipped car. I agree with Installshield here; IMHO it's pretty clear that a stock FS-DE's high-rpm breathing problems are largely due to the conservative U.S.-spec cams and intake manifold, and the engine WILL benefit from improvements in these areas at least up to the ~7200 rpm rev limit of the FS-ZE.

However, if the question is whether the engine will be able to breathe past 8000 rpm, I concur with Jesse that it's hard to tell. It will probably require some head work, and the engine will ultimately be hamstrung by the port configuration and/or the small valves. [For the benefit of gcs118 and other newbies, one of the main limiting factors affecting how well an undersquare engine can breathe is valve size; a small bore limits the diameter of the valves you can cram into the combustion chamber, ultimately limiting airflow.]

I suspect that increasing the rev limit to at least 7500 rpm would be beneficial assuming that the cams and ports are up to the task. Past that, it's hard to tell, and there's a good chance that the engine will throw a rod anyway.

 

the FS is closed deck

 

I do not recommend a redline higher than 7500rpm for a heavily modified street NA FS engine as the upper limits of the bottom end is reached. The FS's weak link is in the rods itself. The crank and pistons appear to be a robust design. Side loading to the block and bore wear from repeated 7000rpm shifts is NOT a problem for the FS even because of the shitty rod ratio. This is because these forces were accounted for when the engine was designed and proper measures were taken to avoid these issues. There's a reason why Mazda allowed for a 7000rpm redline for the FS-ZE in Japan you know. Remember that the FS-DE has just lower compression pistons and a emission & torque biased intake cam as well as the emission restrictive intake manifold. In other words, with proper mods to an FS-DE, doing revs to the FS-ZE's range is perfectly fine. Taking past 7000rpm to 7500rpm, you better be ready for sooner engine overhauls. This is still won't be a major nussiance or problem for a street driven motor though. If you take it to 8000rpm, you better have money growing on trees. Going past 8000 would be insane.

Personally, I wouldn't even bother making the redline higher than 7000rpm for an NA motor. Piston speeds will become ludicrous past that, not enough air flow to require it either. Don't get me wrong, the stock heads are not that bad, but they're definately NOT designed for honda revs. Just a different tuning compromise here, that's all. Nothing bad.

As for FI tuning, don't go past 6500 to reduce rod stresses.

 

The FS-ZE in the sport20 will have AT LEAST 25% power loss because:
FWD FS-ZE sport20s only comes with a slush box
only 4WD FS-ZE sport20s can be had with a stick, but 4WD/AWD eats power, duh

also, the FS block's bore spacing is limited (ok, it's not that bad... but it could be a lot worse). There is NOT a lot of room to bore out. Boring past .050 will weaken the cylinder walls

 

FS-ZE C/R is 10.5:1 according to the FAQ

Who is having probs with knock in the ZE? You may be thinking of the problems upon install due to the difference in the number of teeth on "crank wheel" (not sure the name) the CAS reads. The ZE has fewer teeth than the 1.8 DE, so we had to switch the wheel that connects to the crank and is measured by the CAS. Other than that, I don't know of any problems with the ZE. I even get the same mpg now that I used to get with my old 1.8L except I only use 93 octane.

The only problems, which have been discussed at length, are the need for a stand alone and a nice header.

 

Ok I am corrected. I just went with Corksport's claim of these being stock ZE pistons, which they rated at 10.4:1...
http://www.corksport.com/main.php3?p...3Fcat%3D220746

I had heard of guys on the Probetalk.com forum having problems with knocking, but not on this forum I don't think. I just heard of guys trying to splice the ECU from a probe's 2.0 FS into a ZE's wiring harness (95 and earlier Probe SE's and Bases were OBD 1, which I believe is what the ZE's sensors were set up for) and had some trouble.

 

yeah i agree with you install shield. good calll on that one. your p5 travels at breakneck speeds too.

sincerely,

daniel l. poone

 

If you want an extreme N/A engine, **** the FS...But as far as just bumping the revband up a few hundred rpm and setting a goal of 140whp-150whp, it will be fine. The stock FS-ZE makes 85hp/Litre N/A, which is not bad for a fixed valve timing/duration engine...

I %100 agree Jesse that it will not ever breathe up high, especially really high...But taking the ZE's manifold and cams + pistons, adding an intake + decent header, exhuast and ECU upgrade...You will be right around 145-150whp, which would be great compared to stock....