Hi Mike
Dependant on what vacuum system you have on the distributor (advance or
retard) you should be alright with the UK spec, if you have vacuum advance,
disconnect the vacuum hose and cover the end, set the timing to 9 degrees
(may not be book but is what I settled on for my 1300 herald on twin HS4's).
Graham.
----- Original Message -----
From: Mike Perry <mikep@michindust.com>
To: <spitfires@autox.team.net>
Sent: Sunday, April 09, 2000 7:04 PM
Subject: Heat Shield Follow Up
>
> Previous Problem:
> >>After installing my dual HS4 setup, syncing the carbs (UNISYN) and
> checking
> the mixture (COLORTUNE), the car runs great, except when in stop and go
> traffic or after an extended idle. It "feels" like it is flooding itself,
> and if I can stand the rough running and occasional backfire, it clears up
> in about 1/4 to 1/2 mile. It will remain running nicely until I get back
> into the stop and go traffic. In fact, it has never run better outside of
> this problem...no stalls, and no hesitation all the way through the rev
> band.
>
> I installed Gross Jets in place of the float needles, but that does not
> appear to have made a difference.
>
> Other potentially useful information:
> 72 Spit
> 1296, low miles (6500 mi on rebuild)
> Headers
> Dual HS4s, recently rebuilt (within 800 miles
> Monza Exaust
> Low restriction air filters (foam element type)<<
>
> Results:
>
> Thanks to advice from the list, I have fabricated and installed a heat
> shield, as well as 3/8" spacers between the carbs and the manifold.
(N)Ever
> the scientist, I did both modifications at once so I would never know
which
> had the desired effect!
>
> Long and short of it is that I do not seem to be overheating the carbs
> anymore, and have gotten rid of the 1/4-1/2 mile hesitation and rough
> running. I can't say for certian, as it was only in the mid 40s today
> (Michigan), but I duplicated all the troublesome schenarios without any
> signs of trouble.
>
> I do, however, occasionally have a momentary hesitation right at
> accellertion (in no way similar to the original problem. It doesn't last
> any more than 1-2 seconds. My guess in my float position(s) are out of
> position causing a bit of flooding. I believe one of the floats is badly
> worn at the pin, which may restrict its movement. Does this sound
> reasonable? Just looking for advice before I order parts.
>
> Also, I now that I have my heat shield in place, I am beginning to install
> my Lumitron EI kit. Any suggestions as to where I want the timing set? I
> have the "book" info, but since my fuel system is so different from stock
> now, I'm not completely confident.
>
> Thanks for any help you might be able to provide!
>
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