[TR] To vent or not to vent?

[nwolf at u.washington.edu]

Hi Paul
   Does your car have a road draft tube (left side of engine block)?  If so, then a hose connection to the air filter would tend to suck dirty air into the engine from under the car.  Before retrofitting either of the later topside configurations (valve cover vented to air filters via flame trap, or to intake manifold via PCV valve), you should make sure the draft tube is gone and its hole plugged.
   Alternatively, you could keep the draft tube and fit a little air filter to the vent spigot on the cover.  Or go back to the original valve cover.
   On the other hand, if you have no draft tube, then yes - you really should have the valve cover connected to the intake somehow.

   Removing the road draft tube is supposed to eliminate about half of the car's hydrocarbon emissions (but not CO, CO2, etc.), according to Wikipedia.

   My car (assembled from at least three different donors) arrived with a road draft tube AND a hose connection to an air filter.  I've plugged the rubber hose for now and I'll be removing the draft tube and installing the PCV valve setup in the near future.

-Nick
64-ish TR4 with some early TR4 and late TR4A thrown in.  I like to think of it as a "best of" compilation.


> Date: Thu, 20 Sep 2007 20:57:21 -0400
> From: "Paul Dorsey" <dorpaul at negia.net>
>
>     My question is, since the vc is vented (for now), shouldn't I vent it?
> (Since my air filter does have a place for a air vent hose and it would be
> simple to do.)  Are their other anti-smog measures I should take with
> my '60
> model? I am fairly concerned about the environment and I am
> unconcerned with
> originality.  However, I do not want to sacrifice economy or performance
> unless it makes a great deal of difference.
> Thanks,
> Paul Dorsey
> 60 TR3A w/ a mostly TR4 motor