BP-T or BPT

[bam]

Oh yeah, sorry about getting off topic moderators.

[JesseSays]

You don't see pistons like this everywhere. Mechanical octane due to lots of quench area, bringing the majority of the combustion event to the exhaust side of the combustion chamber, and by reducing hotspots. THIS is how you get high static CRs with lots of boost. That and cams, and all the fast DSM guys are running 272s so you need more static CR just to keep up anyway.


And Sodium valves still don't do enough. What has me thinking though....is doing 5 valve heads with 3 small exhaust ports. Usually in the case of the Audi/VW and Toyota 4age motors, all 5v motors have done 3 intake, 2 exhaust, which just curtains intake flow. 3 exhausts wouldn't hurt flow too badly, and you'd be able to pull a ton more heat out of them.

[bam]

I just have to comment on the piston, that is a full out custom piston by the looks, i.e. the gas ports, so yes I guess with extra quench area you could consider that mechanical octane but I was thinking of something else. 272's on intake and exhaust only hurt spool up by several hundred RPM and make up for it top end, so it's really not that big of a deal to keep up. I know with more valve over lap, a forced induction motor will start to push the air through the intake and out the exhaust making a cleaner less likely to knock charge, but agian I honestly hear it has very little bearing on knock. I'll find the article if I can.

The three exhaust valves idea isn't a bad idea for a forced induction motor. With the size of the exhaust valves not being a bigger factor than the size of the intake I don't ever think it'd make a production car, but interesting idea. Sexy MR-2 by the way, I always wanted an MR-2.

[JesseSays]

that Piston is an off the shelf product....and sells as a set of 4 for under 500 bucks.....same as JE, Arias, or any other common vender.

[turboge]

I'd much rather have a lower compression motor with a large turbo than a higher compression motor with the same. Maybe I'm just used to small turbo's on both sides of the compression scale

[JesseSays]

yes....you are

10:1 and ~10 lbs of boost with a GOOD turbo would be a lot of fun for a street car, methinks.