3/28/2024 0 Comments Degrees advance on timing lightI paid a local shop to install them, including new roller tip rockers and pushrods. I bought brand new 64cc aluminum heads to up the compression. After going through many processes, including timing, I determined that the heads, which are a mid-70’s 76cc low compression smog type of head originally for a 350 sbc, were a contributing factor. It would also be hard to start (difficult to crank) when up to temperature. It has a big, lopey cam, but had starting and idling issues, especially when cold. I have a Chevy 327 of unknown origin in my truck. If the timing chain has too much slack in it, you will need to replace it and at least the cam gear before you will be able to set the ignition timing correctly. Old GMs have a sticker near the rad which should tell you the timing spec at the correct idle speed. If you have a timing light, warm up the engine to normal operating temperature, disconnect and plug the vacuum line to the distributor, and set the timing according to the timing marks on the chain cover and balancer. High mileage small block Chevys are notorious for this and the fact they used Teflon coated cam gear teeth that would break off over time and make the condition even worse. Also, in your case, it sounds like you might have a stretched timing chain. If you are not using a timing light, I would recommend that you do so. An overly advanced condition will cause backfire through the carb and overly retarded will cause backfire through the exhaust. It's an easy mistake to make getting confused with timing marks which can prove quite a problem with how much advance you've putting in to the engine.Usually, hard starting occurs when the ignition timing is too advanced, not retarded. Just make sure you are using the correct mark for 0 degrees TDC and not another mark of 10 degrees BTDC for example. I don't know what the best advance curve is for V8 but I guess the engine builder should be followed as advice. The more expensive timing light with the adjustable dial is a lot easier as when set to 32 degrees the 0 degrees TDC mark on the pulley will read on the 0 degree tdc on the scale. A cheap one that just pulses when the spark fires and a more expensive one with a dial at one end to set the advance you desire to read.The non adjustable light you will need to have either a scale on the front cover that goes out to the 32 degrees which is unlikely or you need to calibrate a mark on the pulley which can be a bit hit and miss getting it accurate. I have 2 different types of timing lights. I wasn't sure what a Sun Distributor machine was so did a search and I think they're a bit more than what you need ) I am still playing with the 1964 Skylark Distributor which fits but I am a couple of months off to see if it will run with it. And I have a couple of distributors to play with. I know I could send the distributor out but that would cost over half of what I could pick up the distributor tester for. Let me know if my thinking is correct or would I be better off with a Distributor Testing machine. I know fine tuning will need to be done on the road. I found a Sun Distributor Tester to purchase, but If my thinking is correct I can use the timing light which is much cheaper. So to me this means at 1800 RPM with my timing light set at 32 degrees I should be at the TDC, if I am not I need to change my springs to recalibrate my distributor, am I correct on this? 1800 RPM seems low or should I add 800 RPM which is my idle speed plus 1800 to use 2600 for 32 degrees total timing. My engine builder told me I should set my initial timing at 12 degrees at idle and 32 degrees total, which gives me 20 degrees mechanical advance. Feb 10 30th January - 31st January 2024.Feb 10 1st February - 2nd February 20.Feb 10 4th - 5th February 2024 - Part.Feb 10 7th - 8th February 2024 - Part.May 04 VAWilliamsburg British And Impo.Apr 06 FLCentral Florida All British C.Mar 24 ILAll Sports Car Swap Meet and.
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