This only applies if you are still using points. Dwell is set with a Dwell meter. The Dwell meter connects between the - side of the coil and ground. Proper dwell angle for your Buick V8 is 30*. It is adjusted, while the engine is running, with a 3/16 allen key through a window in the distributor cap.
Point dwell is the amount of time the distributor points remain closed measured in degrees of rotation of the distributor. You need a dwell meter to measure dwell. Since modern engines have electronic ignition, dwell meters are no longer used on them but, they are still available in parts stores, and online. You hook the black lead to ground on the motor and the red lead to the coil terminal side that comes from the distributor. Sometimes there is a power lead that goes to the battery. There is a two position switch on the meter for RPM and Dwell. The adjustment for dwell on GM distributors is behind the door on the side of the distributor. You have the engine at idle & lift the door and behind it is a screw that you turn to increase or decrease dwell time. You need an allen wrench to adjust it. Just be careful when adjusting the screw that you don't get near the fan blades. It will hurt. Ask me how I know.
Ok I took cap off to confirm I Do have points also test vacuum advance and that works. If this picture works here is under cap.
Yes, those are stock springs. They are higher tension. To total time the car, you want the lightest tension springs you can find so that the weights swing all the way out at low RPM. After you set the maximum timing, you can play with spring tension to bring the maximum mechanical advance in exactly where you want it.
Ok what was the kit you recommend? If my vacuum is working I do not need the canadter right? Can I get the Springs from Auto Zone or no? AFTER lightest Springs and timing is set you said I can play around with different Springs but can I leave the lightest in if not what's you recommendation???
This is the one, you may be able to find it in Autozone. Make sure it is this one, there is another kit for the GM HEI, it is different. https://www.summitracing.com/parts/crn-99601-1/overview/ The reason I like this kit is the springs. They are ideal IMO. If you want to bring in your advance quicker than stock, you will need to adjust the canister for less advance. You can do that with the Crane canister, or you can limit your stock one. Please don't ask me how to do that as it is all included in that very first post of the Power Timing thread. When I wrote that thread 15 years ago, it was because guys kept asking questions about Ignition timing, and I figured, I'll write up one comprehensive post, then just link it when someone asks a question. That isn't exactly the way it turned out. I find myself typing out information that is in the very first post. Read that post 10 times if you have to so you understand everything I wrote. If you need clarification on a single point, by all means ask that. Having said that, I'm on a roll, so let me answer your other questions. The very lightest springs are great for setting the maximum WOT timing, but if you leave them in, they are so light that they can cause some idle fluctuation when going from Park/Neutral to Drive, or when closing the throttle quickly. The weights can flutter around some. Looking at the way the stock timing curve works, maximum mechanical advance happens very late, sometimes as late as 4600 RPM. When you are cruising at a steady speed on the highway, only PART of your mechanical advance is in. The vacuum advance adds 14-18* of timing under those conditions. When you stomp down on the gas, vacuum goes to zero, and whatever vacuum advance you had, goes away. At the same time, RPM increases rapidly and the rest of your mechanical advance comes in. Now, look at what happens when you use lighter springs to get your mechanical advance in sooner, to boost low end performance. Now, same highway cruise scenario, all of your mechanical advance is already in. Add the same amount of vacuum advance, and you may have ping or surging from too much advance. That is why you need to limit the vacuum advance to 8-10* maximum whenever you bring your mechanical advance in much sooner. If you want to retain your stock springs, then you don't need an adjustable canister, nor do you need to modify your stock one. All of this is in the Power Timing thread, very first post. http://www.v8buick.com/index.php?threads/power-timing-your-buick-v8.63475/
Ok last question for the time being. For now until I get the spring kit can I go ahead and tune my current Springs to your 32 degrees recommendation and tdc 12 or is that going to messskmething up??
See, right there, that question tells me that you don't understand the basics of distributor advance. You can't tune anything. Your distributor is what it is. I don't have the specs for it. How much mechanical advance is built into it, you cannot change that easily. The amount will DICTATE what you can run for initial timing for a specific amount of maximum WOT timing. All you can do is bring the advance you have in sooner (with the light springs). You can't do that until you get the spring assortment. You may not be able to run 12* initial. Say your distributor has 30* of mechanical advance. If you wanted to run 34* maximum WOT timing, the most initial advance you could run is 4*(30 + 4 =34*). You might be able to restrict the amount of mechanical advance with a bushing (read the Timing thread, 1st 3 or 4 posts). Bushings come in a different kit. Before you do any of that, you need the light springs to set a maximum advance. Then you can put the heavy springs in and lower the idle as much as possible to read the initial timing. Then it is just subtraction. If you set the total to 32* with the light springs, substitute the heavy springs and determine your initial timing is now 4*, it means there is 32 - 4 =28* of mechanical advance in your distributor. Buick distributors differed widely depending on year of engine, and what engine they were installed in. Maximum mechanical advance could be anywhere between 12* minimum to as much as 34*. We don't know what you distributor has, but you can figure it out with springs and a timing light. That is what you must do FIRST. Until you figure that out, I would leave it alone.
Got it I just ordered kit! As long as I don't get on it I should be able to take it to alignment shop for my alignment tomorrow and get my hopes down tach installed. I'm really excited to see what this thing will do after I install the springs.
Ok received the kit obviously have not installed or checked any timing stuff or dwell yet because I'm also waiting on my cheap dwell meter however, don't kill me but I for the heck of it test drove car tonight because I am taking it to get alignment tomorrow because I feel like I'm floating all over the place while driving. Anyway, as you know car ran fine with the Holley 600 and now I dropped on the 800 Edelbrack AVS and it idles perfect but When I test drive it "not really getting on it because no new kit or timing checked" it seems like it's really stumbling for at least first few seconds then seems to smooths right out. Btw I did change plugs (ngk's 35 gap) and new air filter with new carb. So is this a for sure sign of timing possibly being WAY off? Please know I'm going to do what you said and are teaching but for now tomorrow I desperately need the alignment for safety. Finally, what should idle be hot in gear at stop??
Could be other things, vacuum leak, or accelerator pump/jetting adjustment. Timing might make a difference or not if the problem lies elsewhere.
Getting the idle around 500-700 will be fine to get things close for tuning. Too high of idle will not let you adjust the idle mixture screws on the AVS carb. For starters, get your hoses set up correctly on the new carb, get your idle mixture screws set correctly (screw them in lightly until seated, then back out 2 full turns). Adjust your dwell to 30, then put your initial timing at 5-6 degrees before top dead center. Check your idle and timing as you adjust things. Then adjust your idle screws - use an accurate tach for this - probably one on the dwell meter - screw the left one in until your rpm drops 25 rpms, then back it out one half turn, then do the same for the right screw. Recheck your dwell, timing, and idle again. Once that is done take it for a spin and make sure it's all real hot and don't pound on it. That should make it run well enough to start working on the power timing Larry is helping you with. Make sure you have the hoses hooked up on your carb accurately, and make sure you don't have any vacuum leaks or you will be unable to set anything else correctly! Then post your result here and some pics of how everything is hooked up. I have the AVS 650 on my 340 so I can help you a bit.
Just to start I have the timed port blocked off and running the manifold vacumn line to the distributor as Larry pointed out in the first post that my picture showed it was not correct.
Ok have all the items I need to start tuning. I did get an old swell meter but did not work so I got a new digital meter that checks dwell. Currently as it sits digital gauge reading is 33.6 holds steady. So to start why would the builder or whoever have it at 33.6 instead of 30? I will start tuning but want to see what 33.6 will affect if anything? Also according to my book it says it's extremely accurate however there "could" be a 2.5 percent plus or minus. Also got ideal in park hovering at exactly 800-840ish
Dwell can change as points wear, it doesn't stay the same as originally set, which is why it should be checked periodically. Dwell affects timing, that's why you check and adjust it first before checking timing.
Sure will change to 30. I can say car has not been driven for probably 3 years just fired up and since rebuild in 2008 about 3500 miles maybe put on it. Hopefully points wouldn't crap out that fast
Larry I adjusted my dwell last night to exactly 30 degree and the idle moved up which is fine I re adjusted my idle screw as needed but my question is could the correct dwell adjustment right there affect my timing for the better right off the bat? I say this because the engine just from that change of almost 4 degrees 33.6 to 30* made my engine sound smoother and it fires up WAY quicker now. I remember dwell affects timing so could it of gave my engine a correct timing boost? Still going to get into the timing part but learning this as we go especially when I hear or notice changes I ike to find out WHY before moving on.
