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Switching to dual HS4

To: "Spridgets" <spridgets@autox.team.net>
Subject: Switching to dual HS4
Date: Mon, 12 Mar 2001 00:46:17 -0500
I started my conversion from a single ZS to dual HS4 on my 1977 Midget.
As I started to disassemble my car I found a small crack in the exhaust
manifold.  It has not cracked through yet, but knowing my luck it will
happen.  I could just reassemble it and hope for the best, or I could
upgrade to a header for my 1500cc.  Since much has changed on my car,
non-original dizzy, not much emission hardware, missing air pump I think
I am going to convert it to a UK spec engine.  I was reading my Bentley
manual and this is what I found.  The UK cars had dual SUs and no emission
stuff, no evaporating canister, and no EGR valve.

This is my plan and I was wondering what the list thinks, any thing I
should watch out for and what have I forgotten.

        1.  Replace the ZS with dual HS4s and a UK spec manifold.  The HS4s
            that I have are not plumbed for an evaporative system.
        2.  Remove the evaporative canisters and hoses and plug the vent
          line on the gas tank.
        3.  Use a vented gas cap.
        4.  Replace the cat and exhaust manifold with a header.  Any ideas
            on what kind.  If I keep the exhaust manifold (and hope the crack
            goes no further) just plug the holes for the air rail and the
            EGR valve.
        5.  Try to figure out if I have the correct advance curve and vacuum
            hoses for the engine and dizzy. LOK.

Is there a problem with a UK spec vented gas tank in an enclosed garage that
is attached to the house?  If I burn down the house and kill the dog I am
in deep do-do.

One other thing I noticed the intake passages on the stock 1500 manifold are
1" and the HS4 manifold is an 1 1/4".  Big difference.

------
Bill Gilroy
w.gilroy@verizon.net
77 Midget
90 Shar-Pei

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