Hi I do t know what rear it's running and I wouldn't know how to tell the difference once ive checked the timing I'll see how it goes then. Still waiting for timing light to arrive
Run conventional 15/40, maybe a diesel formula like Rotella. The oil producers have been removing zinc gradually for several years now; first in 'gasoline' specified oils, more slowly from the diesel spec'd formulas. ( If an engine has blowby, the zinc poisons catalytic converters). The zinc is beneficial when you have metal on metal contact like old pushrod, non-roller cam engines. If your engine is 'seasoned' ( all the parts together for years) it's probably ok, but needs to be thought about if you do a cam swap. Then ( and maybe now) you'll want to add zinc to the oil. Opinions differ; read up on it, but unless you're running crazy temps it's better to run conventional with frequent changes vs. synthetic and longer intervals. Just the nature of old engines and the things that happen to the oil as you drive. Patrick
I use full-synth Mobil-1, but I add Red-Line ZDDP break-in additive in order to get the zinc/phosphorus back up to 1300 ppm. The 15W-50 Mobil has this level of zinc/phos in it, but lighter weights (10W-30) only have 900. Some other oils have even less...all to try & get 100k miles out of cat. converters...which are not present in my vehicle. There's a thread on here somewhere which has a lot of suitable oils listed for our engines, along with the zinc/phos levels.
Thanks. For the info len. The. Riv is running pretty sweet now.ive sourced a 800cfm rochester quadrajet 1975 model have you any advice for installing will it need a spacer etc any help would be good thanks stuart
You'll need the primary shaft from the 750 CFM Q-Jet in order to hook up the switch-pitch. The 1975 Q-Jet linkage won't accommodate it. I've already retrofitted my 800 CFM with this arm. Get the 1/4" base gasket with the nylon bushings, and the steel plate/smiley channel gasket for the exhaust crossover passage to go under it...but you have the Edlebrock intake which may not have this crossover... If the primary shaft rattles in the base plate, you'll need to install a bronze bushing kit in order to fix the vacuum leaks. Pull the idle tubes & soak the carb good to clean it out, even NOS carbs can have debris under these tubes which will ruin the idle. Change the pump cup to a blue one which is compatible with ethanol, otherwise it will shrink. Go here for all your parts & gaskets: www.quadrajetparts.com
