The amount of advance added by the distributor, combined with initial static timing, is "total timing" (i. My most recent work on the Jaguar involves ignition timing; a very important aspect of engine tuning for any car (unless it's diesel). Ideally, the timing now should be somewhere around 34 to 36 degrees to total. Our user id is: skipwhite, and our store name is whiteperformance1. I have built many sbc and BBC from 350 HP to 980 HP and several blown engines with big HP. Bump up your initial timing a few degrees and see if it helps the car run cooler. I have had it higher but with 120,000 on the original unit I don't want to push it. The initial timing will depend on the compression. In order to set an initial timing advance or timing retard for an engine, the engine is allowed to idle and the distributor is adjusted to achieve the best ignition timing for the engine at idle speed. 700 inch H-Beam rods and 3. Detonation is the event caused by excessively advanced ignition timing, or the use of fuel with too low an octane rating. Low compression motors like a lot of lead in on the idle so 12-14 is perfect. Best power is achieved when ignition timing is set to fire the spark ahead of time to reach that peak pressure at about 2 degrees after TDC. theni it idles ok. Aim timing light at timing tab and recheck location of timing mark. Chevy Big Block V8. The timing chain method is more common with consumer vehicles and high-performance engines. more importantly you should set the total timing which should be about 32-36 degrees. No need to hold the rpm's high just watch the timing tab/light while bringing up for a short time. Demons love quite a bit of initial timing. , but less than 260 deg. Find helpful customer reviews and review ratings for MOSTPLUS 7500RPM-350 New Racing Distributor for Chevy GM V8 HEI w/ 65K Coil 454 SBC BBC at Amazon. I just wanted to know what variables account for the amount of initial and advanced timing to give to a sbc? Right at the moment I`m running 16 degrees initial and 36 degrees total. The crankshaft sprocket features three keyways to allow you to advance or retard your camshaft with using offset keys or bushings. Mains are aligned honed and block is machined on CNC Mill for stroker crank. You want full timing advance in by 2500-2700 RPM. Block New Dart SHP Performance Block bored and honed to 4. The Racer's Company. Check the timing mark first before setting timing, using both plugs to check the timing before proceeding. But its stock. For example only, we will use the ISKENDERIAN 283-350 Chevy Z-80 cam in describing the proper cam-degreeing procedure (Figure 13). Went 1/2 turn past 0 lash. 8 V6 Chevy S10 needs to be set any time the valves, heads, or crankshaft are worked on. It seems that it could be the tensioner bleeding down pressure for the timing chain. On most classic cars, spark or ignition timing is easily adjustable and should be a regular part of tuning. That's where "your" engine likes initial timing. You use a timing light which is hooked to the #1 spark plug wire and the battery. SBC CHEVY HYDRAULIC ROLLER CAM 383 CUBIC INCH PRO STREET ENGINE 550 HP STREET ROD SETUP. First thing you will need is a timing light that will work at around 4,000 RPM. A widely-held myth is that maximum advance always means maximum power. Tuning Carburetors: A Guide for People as Inexperienced as Me. The EZ-EFI 2. This probably has been done already, which is why it runs bad when you time it to the factory spec's. It is a 350 with 400 sb ported heads with a quadrajet (aka: quadrajunk; dribblejet) carb and a mild lift cam with no increase in duration from stock. Advanced timing doesn't hurt an engine and temps are actually cooler if the AFR is correct at timing. The Affordable Care Act prohibits employers from retaliating against employees who report violations of the Act's health insurance reforms, found in Title I of the Affordable Care Act. (At the correct number of degrees before TDC, both the intake and exhaust valves will be closed. The Bayliner Owners Club is a gathering place for Bayliner Owners and prospective owners. Do not worry about initial timing, as it will be determined by the total timing. i dont have the veci label on the fan shroud anymore. [ Now if I have 14 initial and 21 mechanical I should have 35 degrees or close to it,] Now I start it up cold and check initial. I believe the timing belt interval for all the 100 series engine variants is 150,000km, but this should be checked against each different markets servicing recommendation. It lasts for less than 30 seconds, but is consistent. Pro Flo #3500 sbc, why does the timing go from the initial setting of 10 deg BTDC to 46 deg after I switch the timing set function off?. The ignition is all MSD,I am running the MSD 8489 crank trigger distributor,MSD 8. The timing is not adjustable at all. Nate's 216/235/261 Valve Adjustment Procedures This is a critical, often overlooked part of the tune up of your old GM 6-cylinder engine and it can make a world of difference in how that worn-out engine runs - you may find after doing this adjustment that your old StoveBolt runs so well you decide to ignore the smoking and just run it as is for. non dial back timing light. Don't expect your hot small block to idle at 900 with 8 - 10 degrees of initial timing. next take the boot and plug it into the #1 spark plug wire on top of the distributor. The old advance it til it pings and then retard it usually works pretty good but then check your base timing and advance @ 3,000RPM. R Race Car Makes Surprise Appearance In Florida. timing curve when used with 12° initial timing set at engine idle. MSD Digital 7+ ignition with a 4* retard dialed in set to come on at 4000 rpm with a rpm activated switch. Effect Of Changes In Cam Timing And Lobe Separation Angle The following tables illustrate how variations in lobe separation angle and cam timing will effect the behavior of the engine in which the camshaft is installed. 1985-92 TPI Set Timing and Idle Procedure: SET TIMING 1 Use standard, accepted procedure to confirm Top Dead Center (TDC) of #1 piston agrees with 0 on timing mark. Read More. The gears of the timing chain and timing sprocket need to be aligned to set initial timing. Set your timing with vac can disconnected. TOTAL timing is where it's at- not initial- like Pioneer says- set it for total timing and then CHECK the initial timing. Find CHEVROLET 5. What determines degree timing on a sbc? - posted in General Discussion: Ok I was able to get a new MSD distributor as I had posted that my other new one pooped the bed. Nationwide used car search with free J. Delivered 30-12-2017. I just wanted to know what variables account for the amount of initial and advanced timing to give to a sbc? Right at the moment I`m running 16 degrees initial and 36 degrees total. A timing light is the most common way to check ignition timing. Not crucial for setting the timing, but helpful for general understanding of how the engine works and why timing is set the way it is. I did install it right after the timing chain was installed so technically number 6 comp but I do not think that is the issue. Why 12 o'clock? The timing pointer is at about 1 o'clock. Model year 1965 250-horsepower 327s have an ignition timing of 4 degrees BTDC, while the 300-horsepower version has an 8-degree BDTC. this will most likely mean that you will have to recurve your distributor via springs and weights. So is the carb for that matter but shouldn't we start with timing? I'm looking for peak performance, not fuel economy but I'm not taking it to the track nor will I test it on a dyno. Free Freight Applies To All Advertised Items Shipped To A Commercial Address In The 48 States. This is crucial for optimum engine performance. Went to set the timing and thought, what should it be??? I live at 4500 feet. If you have installed a Fuel Injection system in your vehicle and are having some initial issues here is a quick checklist to work from to get you started. Chevy 348-409 Induction and Ignition Guide - Step by Step The heads and intake are essential for making additional horsepower. This requires using the #5 or #8 plug wire to trigger the time light. With the set timing wire disconnected, your check engine light will illuminate and set a code “42” EST malfunction. Torque distributor hold down bolt to 30 lb. Re: Chevy 305 has rough idle at 8 degrees timing but gets smooth at 16 degrees - 600 I tried rotating the crank as suggested and found a 10 - 15 degree difference between the distributor and the crank. However in terms of high-RPM function, it falls well short of ideal. Ignition timing is tough to understand, but easy to adjust and set. What at times seems like a simple procedure is actually a very precise process. Check to see what your total timing is when it's fully advanced. The three initial carbureted models produced from 250 up to 340 horsepower. Total timing minus your base timing number should meet your engine specification for total advance degrees. Initial Setting The ideal initial timing will pro-vide a clean idle and crisp throttle response. 0 INTRODUCTION: Congratulations on your purchase of a Holley Crank Trigger System!. I had the codes read at the lo. Ive done a few things. Small block Chevys (and most other GM performance V8 engines) perform best when the total timing (full centrifugal advance plus the initial timing setting with vacuum advance hose disconnected) is all in by 2,500 - 2,800 rpm and is set to about 36 degrees. Once initial timing is set, there are two ways of adding additional timing to an engine. All initial measuring should be done before. I have chevy s10 blazer 4. the shaft is misaligned by a tooth or two, the rotor's timing will be off and the engine won't run (or at least not very well). Vacuum advance should be hooked up on the ported port on the carb and as a rough setting should add 10 deg when a vacuum signal is present. If you setup 12. Effect Of Changes In Cam Timing And Lobe Separation Angle The following tables illustrate how variations in lobe separation angle and cam timing will effect the behavior of the engine in which the camshaft is installed. If your distributor cap has a 1 molded into it, that should be the hole that you identified (if not you need to check more thoroughly to see what the problem is, because that indicates that you might have a mechanical timing problem). Since the 1960s, Lunati has manufactured engine components of the highest quality using cutting-edge technology. This causes the engine’s timing to fall out of calibration and often results in a misfire. You will want to be present under the hood to watch for any problems. Most engines need only ~15 at 1100 RPM WOT, and 29-36 degrees at WOT 3000 RPM. Big Block installations should have the initial timing set to "6" deg. Why 12 o'clock? The timing pointer is at about 1 o'clock. Low compression motors like a lot of lead in on the idle so 12-14 is perfect. See a service manual for these locations. This is critical to ensure the lifetime use of your engine. Then turn the crank 90° as indicated by the timing mark, and set each cyl consecutively in the order, 1-8-4-3-6-5-7-2, turning 90° each time. Read More. Note* this post assumes that you already know how to time a running engine, just not one that never been run before or has had its distributor removed and its timing settings lost. This is intended for application with pre-emmission engines (generally pre-1975). You should use timing light at this point to confirm that the initial timing is where you set it, and steady, and then check the timing from idle to 3500 in 500rpm increments. You do not mention what type of heads you have. com Get details about the SB/BB Chevy superchargers and where to buy the ProCharger parts for the GM Carbureted & Aftermarket EFI. See Dyno Chart. Chevy 350 Timing Belt An absence of timing has the potential to ruin any activity, and nothing has more utility in bringing a car to a screaming halt faster than a shot timing belt. Its a well know fact that most chevy v8 engines makes best power with 32 to 36* total timing all advanced and in by 2800-3200 rpm You really need a dail back style timing light to check/set total but you can guess close if you know the facts. A stepper motor is a device that moves a predetermined amount per electrical signal it receives by whatever device is controlling it. The right way to set the timing is to get a dial-back timing light, adjust the timing to obtain the 36 degrees total with the engine between 3000-4000 rpm's. Then back off two degrees. BluePrint’s crate engines have recommended initial timing of 16 degrees or less which should not cause problems as well. When people say "timing", they're most likely referring to ignition timing. WATCH YOUR IDLE RPM WHILE YOU SET INITIAL ADVANCE TIMING!!! You note that the centrifugal advance curve that I recommended above starts at about 800 RPM. There are limitations as to how much timing an engine can handle and understanding the changes that take place will make you a better Tuner. Spark Timing Myths Debunked. The best way to check and set the advance curve is on a distributor test stand, then confirm the results with an advance timing light such as the type we use from the Black Light series of timing lights supplied by OTC/SPX Tool Company. The EZ-EFI 2. Then you can decide where to go from there. 32-41 dist have 15-17 deg while 42-48 have 23-25 deg in dist. If you try to set your initial timing with the engine idling above this RPM point you will NEVER get a true initial advance reading. If the duration is more than 240 deg. Cast Iron with 4-Bolt Main Caps. 3 Start and idle the engine until coolant reaches normal operating temperature. Its a well know fact that most chevy v8 engines makes best power with 32 to 36* total timing all advanced and in by 2800-3200 rpm You really need a dail back style timing light to check/set total but you can guess close if you know the facts. Try setting the total advance, if you don't have a degreed balancer or a timing light to do that, you can get timing tape for you size balancer. I just wanted to know what variables account for the amount of initial and advanced timing to give to a sbc? Right at the moment I`m running 16 degrees initial and 36 degrees total. Modern performance—check. Nostalgic appearance—check. If you are using a crank trigger you will need to check the timing on every cylinder, the timing should be 90 degrees apart from cylinder to cylinder as you go through the firing order. The amount of advance added by the distributor, combined with initial static timing, is "total timing" (i. 1965-75 Corvette engine tune-up specifications including timing, dwell angle, and spark plug gap, and firing order. See Dyno Chart. 3L without Balance Shaft Engine 1991, Timing Set with Gear by DNJ Engine Components®. If you have installed a Fuel Injection system in your vehicle and are having some initial issues here is a quick checklist to work from to get you started. Advanced timing helps cooling. Most engines need only ~15 at 1100 RPM WOT, and 29-36 degrees at WOT 3000 RPM. 10 degrees initial is definatly too low and that is why your engine is running rough. A clear indication that the engine is firing @ #1 is that engine compression will be forced from the #1 cylinder spark plug hole, so feel for air being forced out of the hole as you rotate the crank. ( And the #1 rockers will NOT be moving as the timing mark reaches the timing tab !). Then I hooked up my. This is a little how-to for setting the initial ignition timing on a small block Chevy before its ever been run. The Chevy 216/235/261 Tuneup Guide As with all of the content on this website, you can simply click on any picture to get its largest size. Improper ignition timing can cause several car problems. This is a tool for establishing a baseline spark advance table for your tuning efforts with MegaSquirt® or MicroSquirt® controllers. But its stock. A timing light is the most common way to check ignition timing. When you are finally ready to execute the initial firing, have an assistant inside the car with the keys. When the load on the engine is light. 030 and plate honed for maximum performance. com, 1955 Chevy 1956 chevy 1957 Chevy Forum , Talk about your 55 chevy 56 chevy 57 chevy - Belair , 210, 150 sedans , Nomads and Trucks, Research, Free Tech Advice. No need to hold the rpm's high just watch the timing tab/light while bringing up for a short time. Timing should be checked for its initial accuracy on all of the cylinders. In order. My engine is a modified Chevy 350 with ported double hump heads, roller lifters and lots of more performance stuff. Volumetric efficiency, gear ratio, compression ratio, valve size and lift, weight of car, convertor stall and other factors may vary the carburetor sizing so before you make your selection always contact us for and speak to a reliable carburetor professional who is familiar with Quick Fuel air flows and the various types and series of. The Racer's Company. Chains are generally stronger, so vehicles with timing chains often drive more than just the cam with the timing chain. CAUTION: You must recheck your piston to valve clearance after advancing or retarding you camshaft timing. 5* initial timing with one of these distributors, total mechanical timing will be something over 40* and will result in power loss or detonation depending on the engine. I have a 1970 350 4b high compression. In most cases. B/RBs generate max power with total mechanical advance at 34-36*. Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. The SBC’s purpose is to. Just for your edification, I'll go into the what's what on timing on this page, but if you have zero interest in all of the complexities of ignition timing, why it's important to how well your engine is running, and why it can be disastrous if it's off, you should skip all of the tech talk and simply get out your manual to. Check your engine’s timing before purchasing a new starter. This meant that the vacuum advance was inoperative at idle (retarding idle spark timing from its optimum value), and these applications also had very low initial timing settings; they were usually set at four degrees before TDC or less, and some even had initial timing settings as much as two degrees after TDC. The amount of advance added by the distributor, combined with initial static timing, is "total timing" (i. Correct ignition timing involves more than just setting the initial timing; the amount and rate of mechanical advance, as well as the amount and rate of vacuum advance, is very important in order to avoid overheating. Components Subject To Change Due To Availability. The first thing we should all understand is that making any assumptions when building and tuning an engine leads to problems. Use 16 degrees initial timing advance and 18 degrees of mechanical advance for a total of 34. If your timing advances when you hook the hose then you need to figure out why you have vac at that circuit. For timing 25-65-65-25, the lobe separation is 110 cam degrees (220 crank degrees). First, there's the initial timing, which is also known as " idle timing ", which is where the timing is at an idle without the help of the mechanical weights inside the distributor, and without the vacuum advance hooked-up. 3L without Balance Shaft Engine 1991, Timing Set with Gear by DNJ Engine Components®. The Black Box Programmable Timing Control Module connects directly to your distributor and existing coil offering a fully programmable 21x21 spark table, good up to 10,000 rpm. Factor in your compression ration from above and come up with a number in the middle. Then back off two degrees. Initial Advance: Initial advance is just that, initial timing. This is done with a combination of initial advance, plus centrifugal or electronic controlled advance for engine speed, plus vacuum or electronic advance for engine loading and throttle effect. This is especially true if you aren't aware if all the possible causes of a problem. Once you get to the initial timing ONLY write it down and start bringing up the rpms until the timing stops advancing. Set your timing with vac can disconnected. I have a 1970 350 4b high compression. The proper timing varies from car to car, so always check your owner's manual or shop manual. The best way to check and set the advance curve is on a distributor test stand, then confirm the results with an advance timing light such as the type we use from the Black Light series of timing lights supplied by OTC/SPX Tool Company. If you setup 12. I took off the timing cover and was amazed that there was a very loose double roller chain in there. In order. Be careful when adding timing advance at idle and only add a little at a time. thank you. Now free the vac adv weights and fire it up again and set the idle speed to the desired speed ( I used 650 rpm) and also verify the initial timing. For an initial start, it is recommended that you advance the timing by turning the distributor counter clockwise 10°, and then set the timing by using a timing light. If you have to remove the distributor, position the rotor to the front or No. Total timing vs initial timing for max HP. How do you set the timing on a 2000 chevy 5. Retroactively referred to as the "Generation I" small-block, it is distinct from subsequent "Generation II" LT and "Generation III" LS engines. It was a starter eating SOB too. Total timing refers to the reading at 4500 rpm with the vac. Re: initial timing sbc Post by barnym17 » Tue Jan 08, 2013 10:48 am Ok with the light at 0 start at 34 and work your way up till et and speed falls off. timing vs compression Engineering/Technical Car Forums. There is a simple rule that you should always keep in mind when adjusting engine timing. Checked the timing and it's running 40 degrees of initial timing! Any lower than that and it runs worse or doesn't run at all. Adjust the #2 intake valve: Adjust the #4 exhaust valve: Adjust the #8 exhaust valve. too much and it will be hard to start. Displacement. RUNS ON PREMIUM PUMP GAS. I had my 5. It would be impossible for you to turn on your Chevy 350 engine if its timing belt jumps one ore more teeth. 496 David Vizard Signature BBC Book Cover Engine 782HP 680lb/ft as featured on the cover of How to Build Max-Performance Chevy Big-Blocks on a Budget. A pure stocker will likely want around 8-10 degrees initial with around 34-36 total. , that only affect the efficiency of the spark, but the. i have a sbc 350 with an edelbrock top end kit. Changing ignition timing can be a very basic tuning tool. Setting Initial Timing Stock Chevy Discussion 55-56-57. Only the static initial timing is set by rotating the distributor in the engine. Set your initial 8-15 degrees then use mechanical to get your total. Once you know what both ends are, then you can set the curve. Demons love quite a bit of initial timing. It is designed to work in Mozilla Firefox 6. ” Where as a low compression, low stall speed. Timing Specs for a Chevy Small-Block by Rob Wagner Chevrolet's small-block V-8 engine timing specifications depend on the cubic-inch displacement and whether a manual or automatic transmission matches the engine. too much and it will be hard to start. Displacement. This means that the faster the engine goes, the earlier the spark has to occur. You should be able to check centrifugal and vacuum advance with the timing light and the engine running. 7L/350 Chevy small block Gen I Timing Covers and get Free Shipping on Orders Over $99 at Summit Racing!. how do i set timing on 1998 chevy truck 350 vortec - Chevrolet 1998 K1500 question. 496 David Vizard Signature BBC Book Cover Engine 782HP 680lb/ft as featured on the cover of How to Build Max-Performance Chevy Big-Blocks on a Budget. non dial back timing light. Most factory timing tabs go to 12, so it will be a little BEFORE that. Hate to rain on anyone's parade, but you dont check timing with the vacuum advance hooked up. The Chevy 327 V8 was first introduced in 1962 and was available with four different horsepower options depending on what type of fuel delivery and performance setup was available. 050 of 228 degrees duration intake and 234 degrees exhaust. A high compression engine with a big cam needs lots of timing to burn the required amount of fuel to make it run. Setting timing using a vacuum gauge If the engine is able to start without kicking back from too-early initial timing after making the cruise-RPM adjustment, you. When timed according to specs reconnect vacuum unit and reset idle speed to specs. That's where "your" engine likes initial timing. The engine will always run smoother with lots of initial. The EZ-EFI 2. If you try to set your initial timing with the engine idling above this RPM point you will NEVER get a true initial advance reading. As the build progresses I will cover all the details that goes into building a high quality street engine. Might have been 14. 0, though it may work with other browsers. there may simply be a problem with our. To setup your mechanical advance you first need to disconnect your vacuum advance line. Final Thoughts. It is a strobe which is activated by whichever cylinder the engine "times" off of: #1 cylinder on most every vehicle, except some International Trucks, which for some resaon time off the back cylinders (6 or 8), and have timing marks on the flywheel. To help keep track, put marks on the timing chain cover at tdc + 90, tdc +180, tdc +270, and remember the timing mark will be back in the first tdc position 360° or 1 revolution later for cyl 6. I went to my local Pull-and-Save and found one in an '81 1/2 GM pickup. Chevy Big Block V8. Adjust to the aforementioned 32-34 degrees. If it starts easily, bump up 2* more, heat soak, restart. Ignition timing is extremely critical. 5 mm plug wires and Autolite sparkplugs. If you time it without the shunt you'll be sorry. if it has a points dizzy make sure the dwell angle is also set right. Make sure that you thoroughly go through and understand your car's components before you attempt to adjust the ignition timing for your engine. What is the initial timing for a chevy small block 350? Update: Just a 350 4barrel in an 84gmc pickup. Stock motor. SBC's normally run 32-34 degrees total Mechanical advance. This is a little how-to for setting the initial ignition timing on a small block Chevy before its ever been run. Set the initial timing to desired spec (I used 13 deg). SBC Camshafts - A primer. 908 - PBM Performance - Tmg Set Performance - Steel Gears, Thrust Bearing, Inserts for Cam Adjustment, Cam Button - BBC VI GEAR DRIVE STEP NOSE CAMS. The timing is not adjustable at all. Once initial timing is set, there are two ways of adding additional timing to an engine. The valve seat timing of the Z-80 is intake opens at 57 and closes at 93 and exhaust opens at 93 and closes at 57 checked at. i would set the initial timing at least 12. It would be impossible for you to turn on your Chevy 350 engine if its timing belt jumps one ore more teeth. I have a '78 GMC One ton dully and was wanting to time the ignition better than I have presently. In most cases. This causes the engine's timing to fall out of calibration and often results in a misfire. For example only, we will use the ISKENDERIAN 283-350 Chevy Z-80 cam in describing the proper cam-degreeing procedure (Figure 13). And yes the timing clamp for the light is on number 1 cylinder wire driver side front. Setting timing using a vacuum gauge If the engine is able to start without kicking back from too-early initial timing after making the cruise-RPM adjustment, you. GM Throttle Body Injection 1987-93 LO3 (5. Once you have reset the timing limiter, reinstall the clip that holds the point cam on the shaft, the advance weights, springs, and breaker plate. Its a pre-1980 block. Takes tools to maintain a car, a timing light and vacuum gauge are probably two of the more priority items you'll need to keep things tuned up. Ford calls for all engines to have 4 deg inital advance. A street/strip car that runs on pump gas may “ping” with this much spark advance and will require less initial advance or heavier springs to slow down the “curve. This 383 cubic inch motor uses a Chevy four bolt main block bored 4. , that only affect the efficiency of the spark, but the. To set timing advance when your engine has no degree scale, simply set the advance on this timing light and align the timing mark to the TDC indicator on your engine. To help keep track, put marks on the timing chain cover at tdc + 90, tdc +180, tdc +270, and remember the timing mark will be back in the first tdc position 360° or 1 revolution later for cyl 6. Do you have a vacuum advance distributor? Your initial timing I would set at 12° BTDC and then advance it from there. Timing problems timing retards On initial timing. Some enthusiasts say that a standard total timing (initial timing plus advance) is 34°, others will say 38°, and you will just need to find what works best for your motor. : 20 June 2018 — New-vehicle quality has improved for the fourth consecutive year—by 4% from 2017—and has reached its best level ever, according to the J. Setting timing using a vacuum gauge If the engine is able to start without kicking back from too-early initial timing after making the cruise-RPM adjustment, you. You will have to get it close first to be able to get it started. Find helpful customer reviews and review ratings for MOSTPLUS 7500RPM-350 New Racing Distributor for Chevy GM V8 HEI w/ 65K Coil 454 SBC BBC at Amazon. Dropping the timing back so it doesn't ping is probably ok for today, but I'd be for either buying a timing light or having someone set it that does have a good light. Check the timing mark first before setting timing, using both plugs to check the timing before proceeding. On your 1991, when the distributor is fully seated, the rotor must point to the #1 plug wire in the cap. The Racer's Company. proper timing at idle. Check the plugs again Then start to inch your timing up while watching the plugs. This requires using the #5 or #8 plug wire to trigger the time light. Simply watch the timing marks with the light. Vacuum advance has absolutely nothing to do with total timing or performance, as when the throttle is opened, manifold vacuum drops essentially to zero, and the vacuum advance drops. b) The advance mechanism provides for about 16° of advance, which, combined with the 4° of initial advance, gives a total of about 20° advance. The most critical step in initial start-up is the proper break-in of the adjuster cup to pushrod tip surfaces. 10 degrees initial is definatly too low and that is why your engine is running rough. Early stock SBC 2 hole oil filter adaptor is required. One year later in ’75, it became standard equipment for all, and with good reason. It is a 350 with 400 sb ported heads with a quadrajet (aka: quadrajunk; dribblejet) carb and a mild lift cam with no increase in duration from stock. Connect a timing light, disconnect the EST wire, and crank the engine. This position is slightly before Top Dead Centre (TDC). 0® system actually tunes itself as the user drives, and because it keeps tuning, future engine upgrades are a breeze, meaning that expensive trips to the shop for simple tune changes are a thing of the past. Hagerty's DIY series is your handy-dandy, easy-to-use video guide to tackling small projects any classic car or truck owner might encounter during the course of ownership. Now free the vac adv weights and fire it up again and set the idle speed to the desired speed ( I used 650 rpm) and also verify the initial timing. BluePrint’s crate engines have recommended initial timing of 16 degrees or less which should not cause problems as well. R Race Car Makes Surprise Appearance In Florida. Read honest and unbiased product reviews from our users.