DIY_EFI Digest V4 #501

[Gary Derian]

See the following responses:
Gary Derian <gderian at oh.verio.com>
>
> Yeah, I was thinking about it two ways... assuming that my Internet
> calculator skills are sufficient to the task, a 2L engine that redlines at
> 6.8-7.2K (about where mine does/would) needs ~23036 CFM to feed it. The
> 1300, 12KRPM motocycle engine would need ~26327 CFM (These numbers are

I think those cfm numbers are off.  If you do the math, you will discover
that 140 cfm produces 100 hp.

> I think it is the reason most motorcycles don't have 30Lbs flywheels...
> they don't need a lot of low end torque, being as light as the are, but a
> good top end helps a lot. The individual throttle plates are good for
> better air flow (top end) but don't help with torque the way merged
> airflow intake systems do.

You can merge intake tubes with individual throttles as easily as a single
throttle body.  You gain response with individual throttles.

> > Does the fact that it is an Turbo affect the answers?
>
> Good question! I don't know, but I would ignorantly guess that it makes
> all of the air flow issues for torque irrelevant. Whatever restrictions a
> lack of throttle plates would add could be overcome by jumping the boost,
> and whatever a long air pipe can do for assuring good air flow at low RPMs
> the turbo will do better.

A turbo benefits from tuned low restriction flow just as much as a naturally
aspirated engine.  Making a turbo boost high then restricting the flow
causes extra backpressure in the exhaust and extra heat in the intake.

> A friend was showing me the ECU in his Ford Contour, and it appears to
> have a connector on the back for something.  Anyone know what?  If you
> take off the little connector, there is a card edge there, about 30 pins
> or so, but I don't know what the pinout is, or what it is supposed to
> do.  Anyone know?

I just read a Car & Driver article which tested aftermarket chips.  They
plugged the Contour chip into that edge.