Ditto to what Mitch said except:
1) when I had the nasty vacuum leaks my car was running VERY rich.
2) also, I have the timing set to about 12, not 8.
3) mess with the carb LAST! (ask me how I know). Do the usual stuff
first, distributor, timing, busted float, leaks, fuel lines, etc. Those
SUs are pretty good at staying tuned once tuned.
4) Mitch, I thought the needle in the carb was a UVC?
Joe
72 TR-6 (Supercharged by VIS)
Mitchel Seff wrote:
>Hi List,
>
>At first thought I would check for a vacuum leak as you suggested
>Ashford. The most common spot is on the aluminum manifold. If the
>assembler was not meticulous with making sure the mounting was dead on
>or the use of Halomar was not consitant, a leak will happen. Under boost
>a weak seal will blow out the sealant. Some cases where the aluminum
>manifold was over torqued a leak also happened. All the brackets that
>support the SC have to be properly aligned to avoid stressing the
>manifold. Another spot that is often overlooked is the manifold to head
>studs. These have a habit of loosening causing an exhaust or intake
>leak. If he has a boost/vacuum gauge it should read about 16-18 in at
>idle if a stock cam is used.
>
>None of this is any more difficult than disassembling a normal
>carbuerated car. The same techniques apply to assembly except the use
>Halomar as a sealant. Have the owner remove the damper housing on the
>HD8 and give me the needle size, it should be a UV. If you can, tell me
>if the aluminum manifold has a decal on the top.
>
>I would also check the timing. This should be 8deg BTDC dynamic. Some
>HD8's had to have a small pin hole drilled in the butterfly to allow
>more air in at idle. You can turn the fast idle screw on the top of the
>carb to open the butterfly slightly.
>
>If you want to call me or email I can give you insight in to what to
>look for as well as fax you documentation on tuning and assembly.
>
>I promise it will all be worth it in the end.
>
>Mitch seff
>MS6453@OPTONLINE.NET
>Home or Fax 516-763-3024
>Cell 516-250-9345
>Work Fax 718-849-8567
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