Following my thread on carb insulators, studs etc I now have suitable studs but a new problem. The vertically arranged studs have 1 5/8” centres but the single carb manifold looks to have originally had 1.5” centres and a previous owner has elongated the holes!!!. I might have to live with this as i am not sure i will be able to obtain the correct manifold. Is there any info on this change please?
The change came with the new head which was introduced in 1959 . This head has the milled off fins between the rocker end fixings ,a raised compression and bigger valves. Lots of them around.
Thanks for info just bought a manifold and insulators from NOC shop
88SS/136 with fins referred to as picket fence cause by the 22707 head top mould
also used on 650S/136
88SS/136 1-5/8 studs
Hi David, Yes ,also very common in the UK as it was fitted to the basic 88 ,99 and 88,99DLs as well as the early 88and 99SS for around 3-4 years. Probably not so very common in the USA. With valve sizes and compression the same as the Downdraught head it can perform very well with twin carbs and no problem with fuel flooding or cracking.I was surprised they did not use this head on the 650 std and 650 DL as it would have fitted into the tinware without the need for a special new single carb manifold.