Download the pdf below for some Weber IDA tuning tips from Chuck Schmidt. This thread is a more concise version (no replies) to Chuck's original post on the forum. Thanks Chuck
http://www.gt40s.com/images/howto/LynnMiner/Reference/gt40webercarburetor.pdf
http://www.gt40s.com/images/howto/LynnMiner/Reference/gt40webercarburetor.pdf