Just for the fun of it. Apparently there is a lot less consistency among American V8 engines that I had thought. Now I have a 300 partially assembled on the engine stand. I just put a new timing chain on it, lined up the dots at 12 and 6 like always, and looked at the lifters for #1 cylinder and from all appearances it's on the compression stroke, which doesn't really come as any surprise. BUT. In researching cam sensors for the GM "411" controller it appears this is not at all how it's done in Chevyland, and that makes me wonder why. According to those guys, TDC on the compression/firing stroke of #1 cylinder puts the cam at 12 o'clock, not six. Which makes a difference when you set up a cam sensor. And they say the older chevy v8 engines are the same as the LS (but with a different firing order). I just wonder how it is that I've never noticed this before? Jim
Huh. I really thought someone would have commented on this. So far some say the SBC is like the Buick, some say it isn't. I've not seen anyone saying the LS is like the Buick though.
I'd expect that with the gears "dot to dot" at 12 and 6, #6 is at TDC compression, #1 is at TDC exhaust. #1 will be on overlap, both valves damn near closed--but the intake is about to open.
And if you were talking about Chevy I think you would be absolutely right. But not Buick. I just went back out and double checked and sure enough, when the dots line up on the Buick 300, #1 is at TDC on the compression stroke. That's with the dot on the cam gear at 6 o'clock. And as we all know it'll only go on one way. Jim
I know, right? I never would have suspected if I hadn't been working on this LS EFI retrofit to the SBB. Now apparently the old SBC and the LS are the same, but I don't have any way to confirm that. (different firing order of course) Jim
