Thread: tuning for stock sb 327

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I have a '69 Camaro that I fully restored a few years ago and now that its getting about spring time I'm trying to get it back on the road. It was a full restoration to original condition so there's nothing high performance about it... 327, 2bbl carb, stock ignition, powerglide.

Anyway, I had the engine rebuilt and put a little throatier cam in it, but other than that its all stock. My engine builder set the timing and mixture on it (4 years ago) and I think it could use some tweaking. Can anybody suggest some specs to shoot for and maybe a basic procedure?

Ignition timing:
I think stock is 2* BTC.... is that right? Can I get more advance if using higher octane gas (89, 91)? I need to set the timing at idle speed right? With Vacuum advance disconnected? what should the timing look like at higher rpms (w/ or w/o vacuum advance).

Fuel mixture:
Do I set the mixture at idle speed or a certain rpm. If I remember right I think my engine builder made some adjustments at 2000rpm, maybe that was timing though. Start rich and then lean out until rpms drop, right? drop by how much? stay at that point or turn back some?


Sorry for the newbie questions. I tried searching for some things but most of the results I was getting seemed to be high performance tuning. I'd like to squeeze a little more out of my engine, but its not built for performance so I'd rather keep it simple and reliable. I've got a Chilton's manual to help me along a little, but I'm looking for some application specific tips. Thanks.

-Dave

Anybody got any suggestions? I just got my tach and timing light today, and the weekend is coming up...

I read a little more about adjusting the mixture, I think I might be able to handle that, but I'm still curious what kind of advance I can run?

Also, I'm pretty sure that my damper's timing marks have walked... should the center of the keyway be 0* (TDC)? Anybody know of a place in Virginia that I can get my damper rebuit and corrected? I thought about getting one of those covers, but I'm trying to keep the stock appearance, I might just use the cover to set the timing and take it off, but it bothers me that the original timing marks aren't right.

Dave....

Run all the advance an engine likes....8 degrees for starters..if it pings( spark knocks) back it off....

Ideally you want as much initial as the engine can handle.... that really help the " from a dead stop starting" ....getting the right timing curve can really change an engines characteristics...

This is something you can play with....just some examples you can run a initial of 16 and a full total of 32-38?

or lock it down at the full advance....in my 283 I run it lock-down at 45 degrees....but that 9.2:1

changing the curve means tweeking the distributor....playing with the weights and spring....In most of mine I only run 1 spring and it the lightest I can get.....I like my full advance in by 1500rpm .....depends on how much traction is needed!