Mechanical tach drive distributor This item will qualify your cart for Free Basic Domestic Shipping. Additional shipping charges may apply for oversize items. Chevrolet Big Block V8 Gen. II (Mark IV), Chevrolet Small Block V8 Gen. I. 8.5mm Universal Black Ignition Wires with 90 Plug Boots. such as order checkout, to operate on this web site. Please ensure that JavaScript is enabled. such as order checkout, to operate on this web site. Please ensure that JavaScript is enabled. Our most popular Complete HEI Upgrade Distributor With Mechanical Tach Drive adds reliability, economy, and performance to your 1962,1963-1967,1968-1974 Corvette. TSP's HEI Distributor has everything you need, all under one cap. With a high-quality aluminum housing and hardened steel dual bushing construction, it is built to last. It features fully adjustable mechanical and vacuum advances, meaning precision is a breeze. It has a high-output module, high-spark 65,000 volt coil, solid brass terminals, and an easy one-wire hookup. This distributor also comes with a mechanical tachometer drive, so it's perfect for Corvette applications. You must have JavaScript enabled in your browser to utilize the functionality of this website. This is the main shaft shim or shims, which take up endplay. Endplay must be checked with a thickness gauge. Allowable endplay is 0.006-0.009 inch. You can run it a pinch more in the 0.010- to 0.012-inch range and still be safe. Install the tension pin and make sure installation is tight. Select your preferred location and we'll note which parts are ready to be picked up TODAY. Please upgrade your browser from current version (Mozilla Firefox for Mobile - 23). CHEVROLET BIG BLOCK V8 GEN. II (MARK IV). Summit Racing SUM-850001-T - Summit Racing Blueprinted HEI Distributors. This is the original revolutionary PerTronix Ignitor I, which was introduced decades ago and remains the easiest modification you can make on your classic Vette. It installs in less than one hour. Set the gap between reluctor and module and you're good to go. JavaScript seems to be disabled in your browser. Order this item and get free delivery and handling on your entire order! Offer excludes truck freight and oversize fees. Valid on orders shipped in the contiguous United
States. Account confirmation is required. Please, check your email for the confirmation link. Tech Note: Compatable with all 1975-1981 HEI style small block Spark Plug Wires; Use Part 614956 for Big Block Applications. Keep your 1962-1974 Corvette 's original factory mechanical tachometer AND ditch the troublesome breaker points for good. This NEW Mechanical Tach-Drive H.E.I. We ship in-stock parts via ground shipping the same day if ordered by 10:00 pm EST. Monday through Friday. Learn More. 8.5mm Universal Red Ignition Wires with 90 Plug Boots. Completed Delco tach-drive distributor is ready for installation. Remember, if you're running a roller cam you will need a hardened distributor gear. If you're running a flat-tappet cam, an iron gear gets the job done. I prefer to receive occasional updates with special offers from carefully selected third party partners. Let me explain this in another way... and please take no offense to the redundancy. You are not alone in not understanding this. I've witnessed so called "marine mechanics" set BASE advance ONLY..., and then walk away, thinking that they are done! All times are GMT -4. The time now is 06:34 AM. 04: Unscrew the tachometer drive cable from the cross gear assembly and pull the cable free. Now look at the curve for this same XXX engine in a Marine version. Most often these kits are for automotive use, where curves and limits are quite different than what best suits Marine Engine loads/rpm. 13: Remove the shop cloth and gently lower the distributor back into the block. If you haven't disturbed the orientation of the rotor shaft, it should drop back in place without a problem. If it doesn't, remove the distributor again and check the position of the oil pump drive key in the bottom of the shaft and orient it to match the slot of the oil pump drive, visible by looking into the hole in the block. Then send this data, along with both distributors, out to a shop that over-hauls these. 28' SDN F/B w/ twin Volvo Penta 5.7L DP's. 28' SDN F/B w/ twin Volvo Penta 5.7L DP's. With regards to the Y and its distributor, the more initial advance you can run without ping, the snappier your car/truck will accelerate. The more load that your Y block must pull around, e.g., if it is heavy or you tow or haul loads with it, the less aggressive you can be in adding advance, and the less improvement you will see. On the other hand, many Ys have relatively low compression, which helps quite a bit in how aggressive you can be
in speeding up the advance curve. The springs adjust the advance rate. Where the distributor is bolted down determines the initial advance, the amount of travel in the mechanical advance determines the total advance, and the springs determine what RPM total advanced is reached. Lighter springs allow the mechanical advance to move more easily so you will reach total advance at a lower RPM. Stiffer spring will delay the total advance. Most distributors use two springs, a small one and big one. The big one will usually have a bit of lash so the small one does all the work at low speeds. This allows the advance to come up quickly off idle. Once the lash on the big spring is used up the weights will be trying to pull both springs so the advance rate will slow down. The chart below shows a typical stock advance "curve". It is the dual springs that give it the curve. If there were only one spring the chart would just be a straight line. Unless you know exactly how to set one up, and exactly how to check the curve while installed in the engine (or if you own your own distributor machine), etc. you'd best leave this to a pro!. One (1) degree of change to the advancing mechanism, equals two (2) degrees at the crankshaft. Two degrees of change to the advancing. well, you get my point! The springs control how fast the advance comes in, compared to the rpm. One spring is loose and heavy, and the other is light. The light spring controls the advance at the lower speeds, and when the weights are farther apart at higher rpm, the heavy spring slows down how much advance will be added as engine rpm climbs in the higher ranges. Look to have all of the distributor's advance in by 2500 to 3000 rpm. The exact point is the one that is near, but before you get pinging. This will depend on how heavy your rig is, so you do have to spend some road time testing how you have everything set up. This can be tedious, but it is the alternative to giving someone big bucks to give you what they think will work on your car, as opposed to something you have customized for it. Total advance is the most critical setting. Short of a dyno the best way to find what total advance you need is some track tuning. The MPH reading at the end of the track is your best indicator of engine output. Make a run or two to get a baseline then increase your total advance and make another run. If the MPH increases advance it some more and run again. Continue advancing the ignition until the MPH starts falling off then pull it back to the point where you had the highest
trap speed. It may take quite a few passes until you find the optimal setting. Total advance is initial advance plus mechanical advance. There are two ways to change the total, adjust the initial advance by turning the distributor or adjust the mechanical advance mechanism. The easiest, and cheapest way is to just turn the distributor until you get the total you want then just leave the initial wherever it ends up. If you want more control over the initial then you need to adjust the advance mechanism. If you have a total of 36 and want to run 12 initial then you need 24 mechanical advance. Aftermarket distributors will have replaceable bushings to adjust mechanical advance. Stock Ford distributors have two slots. There is a pin that sits in one of the slots to limit travel. To change slots you simply remove the armature assembly turn it 180 degrees and reinstall it so the pin is in the other slot. The slots are numbered as to how many distributor degrees it will pull in, double it to find the amount of crank degrees. So if you want 24 mechanical advance you need to find an armature assembly with a slot marked 12L. My distributor is setup with the stop in the slot marked 13L, this means 26 mechanical advance. The other slot is marked 18L which is 36. I wanted less than 20 so I made the big advance spring a stop. I wrapped the coils with copper wire then soldered it so it was solid. Now I can adjust the total advance by bending the adjustment tab through the hole. MarineEngine.com does not offer troubleshooting assistance or repair advice by email or by telephone. You are invited to join our public Boat Repair Forum to seek assistance from other members. You may also visit the Boat Motor Manuals section of our site to obtain a service manual. Manifold vacuum allows you to close up the throttle blades on a built motor, but if your stock motor is already running the throttle blades in the right spot then switching to manifold vacuum may require closing the throttle too far, completely blocking off the transfer slots. Depending on how much air is coming through the PCV, you may not even Anonymous on 2005-2013 C6 Corvette Kooks Header Installation. Initial advance isn't very critical. Usually you just set the total where it needs to be and leave the initial wherever it ends up. Once you found the best total advance setting you can play with the initial. Basically you want to run as much as you can before the motor cranks over hard. With the motor warm pull the timing way up and try to start the
motor. If it cranks real slow then pull it back until it spins normally. Lets say that is 20 and you ran best with a total of 36, that means you need 16 mechanical advance. Any time you adjust the initial you need to adjust the mechanical advance so the total stays the same, this is easy to do with my distributor mod above. Now if you're running tall gears and/or a heavy car you will probably encounter some sort of pinging if you stand on it with that much advance. If it happens at real low engine speeds then you need to pull the initial timing back. If it happens at moderate RPM levels then you can probably fix it with the advance springs. These are an array of pistons, not necessarily all Marine Engine pistons, and not all damage is from detonation. Be sure that the shop knows that this is a Marine application, and to follow the curve provided!.