high compression pistons
 

Mazda speed sells high compression piston sets for the 1.8L and 2.0L engines for 3rd gen.Has anyone seen the results on dyno testing?And what does it do to the gas mileage?Cuz for the price I think Its interesting..:)

I guess so,since the engine doesnt need that much gas to give the same performance....hmmmm hhmm
but what about torque and hp increase?

traffik
 

Before you buy the pistons, are you going to eventualy add a turbo? If so, you might not want to raise the compression too much. If a turbo is in the future then the pistons may turn out to be a waist. If you're not thinking about the turbo then the pistons would probably be a good upgrade. Just my opinion. :dunno:

the compression on the Mazdaspeed pistons is 10.7:1 , the stock FSZE is 10.5:1....

im ordering the MS pistons and the cams withing the next 2 weeks....

Mazdaspeed says the Pistons wont work unless you can upgrade your ECU (which we cant really do) They said if they can find a way to use the Jspec Familia ECU in place or ours or with ours (which they dont expect to be able to do) then it wont do you any good. If fact, based on the discussion I had with them & the answers we found, I figured they would take that off the list of items for our Pros. I was hoping to sell them because they should (if they worked corectly & we could adjust our ECU's) gain quite a nice increase in HP. I think they said purely based on calculating the numbers, supposedly would be a 15-20HP increase.

Theoretically, if someone gets the pistons (and cams) and uses a stand alone they should be able to post their custom fuel/air maps and anybody else with the same "stand alone" system should not have to "tune" their car, just input the new map. Is this correct? Has anybody dynoed their car with the MS or JSPEC pistons?

very slight tuning, I'm assuming. I believe that the flyin' Miata turbo kits with FMU come with some sample maps and they suggest slight tuning changes for each car. I hope something like this will be available soon for the Proteges.....

Not as slight as you might think. Not everyone is going to have the exact same exhaust, intake, cam timing and such, so what works for one configuration might be way off for another. Especially if one’s tuned to the max and is sneaking up on the lean edge of F/A, and just avoiding preignition. Serious problems could result beyond these limits, and less than peak power at anything missing the mark by much.

The fact is that every little mod made to an engine to increase flow and volumetric efficiency requires a change in timing and mixture to gain maximum benefit. Since our cars are tuned for low end torque and ultra low emissions, the stock ECU is going to be the major limiting factor in getting significant gains from our motors. I think Mitch pointed that out.

So if you plan on making notable changes to engine configuration, you better resign yourself to that fact that you’re going to need to do something with engine management. In reality it’s the first thing we all should be considering from a performance standpoint. Second on my list is a fricking header, damn it!

when i said slight I menat it won't need to be on a dyno for 20 hours. You will still need to make some changes as Psuedo said bacuase not all FS's are created equal. I have a friend who works at a speed shop and they hook me up so I will have them do all of the tuning more than likely. They are the professionals and I am just the weekend automotive mechanic.....