jmauld

The cam specs are there?

zeus

TheMan is right he’s got all the info except valve sizes – at least I couldn’t find it. I know I wrote it down somewhere, but I can’t find it now.

1991cc
130 hp @6000
135 ft-lb @ 6000
83 x 92 mm
9.1:1 (fs-de) 10.2:1 (fs-ze)

I’m not looking to produce high rpms with a bore x stoke like that, but I do think the motor could be a good low end torquer for a 4cyl. About 7000 rpm would be tops. Mine’s seen a good bit over 7500 just to look for a rev limit, but in my short try I didn’t find it. Right now there’s surely no need to run that high as power drops like a stone. I heard somewhere that there is a fuel cut off that comes in after the ECU detects sustained high rpm operation, but that just don’t sound right.

Maybe someone can enlighten us on that subject and give us the valve sizes. Hey while we’re at it anybody know the valve spring compression rates? Chamber volume? Valve length?

I’m surpised that no one had any input on cam profile other than to suggest buying the factory cam. It may be JDM but it is still a factory cam. Thanks for the effort JasonC.

Eric F

The compression on the FS-ZE is 10.5:1.

njaremka

a suitable profile depends on what you want the engine to do, and where you want your power band. i would suggest going to one of the custom cam places and find out if they have any insight as to how you should have your cams ground in. that is probably not what youwanted to hear, but it seems to me that there just isn't a high number of very technical people on this board.

as an interesting side note, i have been looking into adjustable cam gears over the past week (see my other thread about that) and the BP motor in the miata likes some very weird profiles on the cams to produce good low end torque and better high end power.

jmauld

That's so true. There are a few technical people, but you have to read through so much crap to get that info. All of the protege boards seem to be that way. Speaking of which, why are there so many of them around? There's not enough information for one board, much less 5 or 6.

Have you considered just moving the cams around. You may not be able to move the intake cam because of the sensor, but you can adjust the exhaust cam without any effects to the sensor. You don't need an adjustable cam gear to readjust the cams.

Eric F

The adjustable gears would make it considerably easier and less time consuming due to not having to remove the timing belt each time you want to try a different setting.

jmauld

No doubt, plus the gears will allow for better adjustment resolution. BUT, if there are no gears....?

njaremka

my point exactly.

jmauld

So, who's gonna be the first to attempt adjusting the factory cam gears??? :-)

Anyone with access to a dyno?

Eric F

Then we must get someone to make them! To tune the engine by adjusting cam timing requires a dyno. Dyno time isn't cheap, and adjusting cam timing by having to remove the belt is time consuming. This seems to mean multiple visits to a dyno to test results. Too expensive and inefficient for me. Unless someone has free access to a dyno, this doesn't seem very cost effective. What about the Speedvision World Challenge Touring Proteges? They must have some adjustability for tuning, maybe we could get the gears through AWR, Tri Point, or Sunbelt Performance?

jmauld

I doubt it. Adjustable gears are heavy compared to non adjustable gears of the same material.

They probably have custom cams made, that already have the appropriate cam specs for max power.

zeus

Custom ground cams is what started this thread in the first place. Adjustable pullys would be nice for dialing in just the right overlap though.

Soon as a good header option becomes available I'm getting the grinds, doing the head work and modding pullys if I have to. Just trying to get info now, but it looks like I may be the first that has the ***** to cut into it.

Eric F

What little bolts in the middle? We're talking about the stock camshaft gears, not adjustable, since there doesn't appear to be any available yet. The stock gear has slots that allow it to fit on the camshaft one way, you can't adjust the position of the stock gear on the cam. You could rotate the the cam and gears' position by moving it forward or back one position in relation to the timing belt, but that's time consuming, and not very accurate, which was my point. We need adjustable gears as another method of tuning the engines power band.