There have not been many entries of late, so I thought I will put a new topic up on the board.
Many CIH 6 cylinder owners are struggling with their 35/40 Zeniths carburetors. I battled them for many years in the hope that I would beat them and get them to run right. I got frustrated and in the end I purchased a set of Webers from the USA. New Webers are very cheap there. I purchased two new kits from Pearce Manifolds inc. The kits were originally for Jeep and they contained a 32/36 DGEV each. There was enough hardware with the kits to make up a new linkage system as the original Opel linkage system is not suitable.
The immediate problem I had was what jets should be fitted to these carburetors for the 2.5 liter CIH to run right? The jets which were in the purchased carburetors were way too big. Luckily there is a Swedish website that lists all the old Opel models with an after market Weber conversion. It shows the required jets by vehicle model. Someone did a tremendous job to list this valuable information. It was a gamble because how accurate is the information? In order to make sure that the jets were indeed correct, I fitted an Air/Fuel Ratio gauge to the car. In the event things were not right, at least you can experiment with smaller or larger jets and get it right.
The Webers are on the car and I am driving! The first thing you notice is the increased power compared to the old tired Zeniths. The other thing that becomes obvious is the strong suction noise through the Weber filters. Adaptor plates are available from Weber to fit the original Opel filter housing though.
I am back in control!
I guess this topic is not so relevant to New Zealand, as all your cars are fuel injected.