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Mazda Engine Performance \  hi comp pistons

hi comp pistons

Mazda Engine Performance Mazda Engine Mazda Tech
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manicmazda   +1y
alright guys the time has come to totaly rebuild my mazda b2200 so how hi can you go with a webber and header stock cam ? looking to pick the best CR you can get with the stock cam
jenko   +1y
Wow, I hope someone has done this before.
I remember reading a little something about compression and cam duration.
I imagine the stock cam will have short duration due to it's low compression.
You can't go sticking much more compression at something like that, you won't end up with enough a/f in the chamber.
Come to think of it... I wonder if they're really short duration and that's another reason why the damn things make NO power when revved.

Long rant short, If you're going to do more compression, change the cam.
In my most humble and ill informed opinion.

I now want to go and read all about compression vs cam duration etc.
But I should really make some signs

oh... unless you were talking of interference issues?
manicmazda   +1y
well looks like the f2h2 had 9.2-1 and made 130 hp soo im thinking 10to1 and what is the b2200 cams duration any way? i never looked it up it
jenko   +1y
Another link to mt
manicmazda   +1y
well we can help the stock cam by retarding it
jenko   +1y
Is there an actual dyno run on there?
I see sim ones.
Seems like people have and good seat of the pants results though.
Give it a spin!!! Do it do it do it (come on guys, chant with me).

10:1 compression would be cool, you're only gaining 3-4% horsepower for every compression point.
3% if talking to an engine builder customer of mine.
Whereas you can gain about 26% more capacity for air for every one point you drop when you're boosting it.
He builds subaru engines mostly
manicmazda   +1y
yea i hope to couple it with a hi rpm build and make the most of my 2.2
manicmazda   +1y
ever time i start to retard it something happens and i end up not
jenko   +1y
"Something" being non-mazda related?
manicmazda   +1y
yea mostly school