RodsINTOMG wrote:
>
> I think the cure for this condition is what A. Graham Bell describes in his
> book" Four-stroke Performance Tuning as a evacuator breather system. I
> bought the device and it is simply a piece of 1/2" black plumbing pipe cut
> on
> a angle with a one way valve on the end. The theory is that you weld this
> pipe into your header and connect it to the valve cover. The flow of
> exhaust
> gas over the angled pipe creates a vacuume of about -5lbs and exhausts blow
> by pressure in the sump into the header.
Hooo boy. I got severely flamed over this about a year ago. But since I
have good scar tissue I will venture some answers! I installed this type
of device on my two litre car and used it for one season. It worked for
me and two other not-to-be-named drivers. I removed it because it is
illegal in some circles and was roundly criticised on the net.
>
> My questions are:
>
> 1. The 1/2" black pipe looks like it would work fine in the headers of a V-8
> engine, but in the dmall diameter pipe of my header, it looks like it might
> be
> more of an obstruction to exhaust flow. Any thought on this issue?
I used a tube that was 1/2 in. diameter - a 1/2 black iron pipe has a
pretty large O.D.
>
> 2. The regulations for the group I race with call for "two separate catch
> tanks, each one quart capacity required for the engine and for the coolant
> system. They must be securely mounted and easily accessible for checking
> and
> emptying". I was thinking of using a metal one quart can (brake fluid can)
> which I would weld in a metal pipe that could attach to the crankcase
> evacuatior and have the hoses I now have from the tappet cover and rocker
> cover attach to the top of the metal can thus providing a vacuum on the
> sump.
The can is not necessary. The two vents are not necessary. Just hook
this baby up to one engine vent. It will draw a vacuum on the inside of
the engine.
> I would also need a breather on the rocker cover to let air in.
If you install a breather, this setup will not work. It must pull a
vacuum.
Would CSRG
> accepth this setup?
They will have to answer this, of course. I was told that VARAC
(Canadian body) specifically prohibits the use of the device. Ex-SCCA
folks told me it was illegal.
The objections seem to be that if you have major blowby problems or if
you have a major engine failure, you will oil up the track. I really
didn't quite follow that logic -- if the engine blows, everything is
going to get well oiled from openings other than the exhaust pipe.
My experience with my homemade device was that it worked great, the
engine stopped leaking, it ran fine, etc etc. However, in the interest
of not upsetting my fellow competitors, I removed it and now my engine
leaks like a seive, as Brit cars are wont to do.
> I would appreciate any dialog on this from anyone "who has been there and
> done
> that".
Been there, done that, let the flames begin.
>
> Regards,
>
> Rod Schweiger
> '64 MGB Sebring Replica #119
>
>
>
>
--
uncle jack in frigid iowa
TR4 Rallye Replica vintage racer
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