question : i have a sbc that i fresh built ... if i am off a tooth on cam timing gear what type of response will i see ............ i move timing to just before binging and idle does not change , motor seems to laboring with out response ........... it is 283 bored to 301 , Engle cam . flat top pistons , hei , i am totally confused , i have adjusted lifters,timing ,carbs , 2 new hei,s , all this several times ...Help please !!!!!!
If it’s retarded by one tooth it will be so lazy it won’t rpm at all. If it’s advanced it will run but higher rpm will probably not be attainable. I’ve run 6* advanced and the 350sbc really had torque from a stop. I think one tooth is about 12*.
Take off the rocker cover on the bank with Number 1 cylinder. Rotate the crank by hand in the same direction as when the engine runs. Watch the #1 intake valve very carefully. It should just start to open in the general vicinity of 20 ° BTDC, similar to ignition timing. Confirming the timing marks on the damper is always a good idea.
SBC cam timing marks are pretty basic, the crank gear can have 3 marks/ symbols, triangle, circle, rectangle for example, that's for advanced or retarded cam timing,and straight up timing, straight up timing puts the crank key at about 2 o' clock using circle or dot, does that sound like what you remember? If cam is hydraulic, oil in lifter with affect ability to accurately check cam timing at lifter with dial indicator other than it opens and closes, solid lifter is needed for that type of checking. Do a compression test and post actual ignition timing specs that you experimented with along with vacuum readings , also cam specs ,as your info is pretty incomplete other than you swapped parts and runs crappy.
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