Lucas distributor advance weights. The ones with the slack secondary spring usually brought in the advance earlier. These two parts rotate against each other depending on the “advance” of the distributor relative to the engine RPM. engines (4 degrees centrifugal @ 600 rpm plus 10 degrees Aug 30, 2011 · I just purchased a 1970 Elan SE and am looking to fix a “no advance” condition. 1°/1000 RPM. Find many great new & used options and get the best deals for Advance Weights, Lucas Distributor, Late MGTD MGTF, MG TD TF at the best online prices at eBay! Free shipping for many products!. 5 deg at 1800 RPM By Lucas convention, these are all RPM and degrees at the distributor. units were usually used on distributors which gave a much greater total mechanical advance, then those using ported vacuum. The first step in tuning an advance curve is to determine the maximum ignition advance the engine can tolerate, and subtract from that figure the initial static advance. In original box. However, I would not shift the Shaft and action plates between the two units. The manifold fed the vacuum advance unit, with the advance curve only giving around 5-7 degree maximum. Bob weights on the cam. I would like to replace the Lucas dist. Shafts are plated and refit for proper cam spec. -Fwiw---Keoke Oct 12, 2024 · note: box part number is 400149 but this weight looks identical to part number 400150. 7°/1000 RPM to 5. with either a similar unit and replace the points with an electronic pick-up OR abandon Lucas for something else. In another part of the article it is claimed that both springs were the same. the cam are the bob weights that fly out under centrifugal forces and cause the cam to advance. There will be some confusion when refering to the direction of rotation of the distributor. Advanced Distributors offers a comprehensive distributor rebuilding service for ALL Lucas distributors, as well as most collectors and antique vehicles (no Ford or John Deere!!!) Our rebuilding service is the most comprehensive available, despite our bargain pricing. lucas_distributor_specs. May 11, 2018 · Breaker plate slots back together. For guidance on this determination, see Hammill’s How to Build and Power Tune Distributor-Type Ignition Systems 3. Any recommandations Apr 2, 2011 · The thing about the springs and maximum advance are that they vary from make to make and model to model, so a landrover 25D will in all liklihood be totally different from an MGB 25D. The advance curve is: 0 deg below 250 RPM 3. It should be noted that all the advance weights are the same throughout a distributor family so they cannot be changed to affect the advance curve. Mar 19, 2006 · Well Cutlass Dough's input seems about spot on. Stock Ford distributors have two slots. g. Now for the cam and bob weights. Curve tuning: the cam The cam performs two functions: • Open and close breaker points Manifold controlled vac. the 40897 and 40916 for the 18G, GA, GB etc. The third was an intermediate type. Lucas 23D4 - a 23D6 - a Lucas mechanical advance only distributor. The secondary spring would have to be changed from 270 lb/ to 125 lb/, increasing the rate from 4. Use the contact breaker plate and the Vacuum advance units from you original dizzy and you should be good to go. Besides Lucas, we also rebuild Bosch, Delco, Prestol I discuss the basics of tuning Lucas distributors. Shift the Weights and springs after giving the replacement unit a good cleaning up and lub. The break in spring rate is needed about 8° after the start of advance, or 4° distributor advance, consequently, if the distributor being worked on is the one in the example above, the free length would be 0. The weights and the different types that are LUCAS DISTRIBUTOR SPECIFICATIONS - IG-126. This is the long list of all known original Lucas distributors (and specifications). The 23D4 is what the early/mid 1960's mini cooper S had, and all the works Sprites/ Minis etc - with a fixed plate, no Vacuum advance) So I now have one of the 'mythical' works type Lucas 23D6 distributors (as Aug 19, 2022 · In both cases the advance springs set was listed as Service Number 405396/S. Aftermarket distributors will have replaceable bushings to adjust mechanical advance. Denis In theory the centrifugal figures show only the additional advance at the given rpm, whereas the strobe figure is the sum of the static and the centrifugal advance at the given rpm, and this can be seen to be true with some distributors e. Click for 20-page 159-KB pdf file. The perfect moment for the spark to happen will be dictated by a number of factors such as fuel octane, engine compression ratio etc, which is why different engines need different distributors. The advance weights are not moving smoothly which could be the cause of the problem. The distributor mechanical advance will be ½ that figure. All parts are replaced as needed, bushings, bearings, springs, weights etc. Took out and dismantled the Lucas 23D4 distributor. The moment at which the spark should occur in the cylinder is not always the same, but varies with engine load and speed. 5 deg at 1000 RPM 6 to 7. Totally legal in all historic racing. Lucas distributor advance weight original NOS 400149 400150 | eBay Dec 6, 2016 · If you want more control over the initial then you need to adjust the advance mechanism. Kind of a mix between the first two. If you have a total of 36° and want to run 12° initial then you need 24° mechanical advance. pdf . 707±. Jul 4, 2015 · All 25D distributors had the same bob weights so the different advance characteristics required for different models like high or low comp, carburetors, emissions and transmission was accomplished by various springs and the length of the advance stop. I go over the basics of springs, both primary and secondary. 5 deg at 1400 RPM 7 to 8. … and here it is, slotting back together. 3. My original Marina 45D had a maximum 15 degree advance stop and the older 25D I now have has 10 degree advance stop. The 21 degrees stamped on the cam, indicated the distributors static advance setting. 5 to 4. The older style Lucas 25D distributor with vacuum advance. Lucas 45D distributor with one-piece contact breaker and non-adjustable vacuum advance unit. The mechanical advance is delivered by centrifugal bob-weights that spin inside the distributor body. 4 and 6 cylinder Lucas distributors. livydd jcnnwji czb jvey ogc oesw jximnn hrsgp eoomsl tgctis