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MG MGB Technical - Electronic Ingnition System
| About 20 odd years ago, I had the original electronic ignition system on my 1977 MG replaced with a "points type" distributor after having about three module failures. Just recently I read that there is a newer and more reliable ignition unit (Lucas 45DM) and I am now contemplating to convert back to the electronic system. That being said, I would like to know if there are any owners who have the newer system on their cars and what do they think of them. I would greatly appreciate any input from other owners on this subject. Thank you. |
| Donald E. Elliott |
| Don, The Lucas 45DM4 electronic ignition with the remote amplifier is actually a GM Delco HEI ignition system. This system replaced the Opus electronic system that was used on your 77B and was later factory installed on all 80B's. I have one on my 75B and it works great. You can be assured of its reliability as GM has installed it on millions of vehicles. Furthermore, in the unlikely event that the HEI electronic module should fail, you can buy one at any parts store anywhere. |
| Steven Rechter |
| Can this electronic ignition be used in the European version Lucas 45D distributor, either as a straight fit-in, or with modification. The question arises because I am changing the Zenith carb to twin SU's, and removing the exhaust emmission stuff. I've been told that I can't use the Lucas 45DM4 as is, because the bob weights or something are all wrong for an SU set up, so I have to obtain a Lucas 45D distributor from somewhere, and if I wish to remain with electronic ignition, either buy a new Crane or pertronix system, or succeed in fitting the CEI/ GM Delco kit to the new Lucas 45D. Has anyone done such a thing?? I'd really kick myself if I learned that I could have already used my existing electronic ignition, after spending hard earned cash on a replacement Crane or Pertronix system. http://com.universitymotorsltd.com/qa/413/html |
| Tom |
| Thanks, Steve, for that revelatory piece of information on the GM HEI ignition used in the later Bs. I think that is the first time I have heard of that on this BBS. This gives folks yet another option, and as you say, one that makes pretty good sense if they can mount it and use it in their 45D4 distributor. There are other modified 45D4 dizzies on the market, variously called "Euro-spec", Aldon, etc., and even they could benefit perhaps using this triggering system. I sometimes think we spend so much time trying to recapture the performance of the early cars that we neglect the later ones, as tho any of their OE "performance mods" and changes are of lesser consequence than the early setups. This is not necessarily true, and frankly, if we could use the HEI system, it might be very worthwhile for the average daily runner out there. It might even be of value for a genuine performance increase. Thanks again for the insight. |
| Bob Muenchausen |
| Bob Muenchausen's comments are encouraging if it means that we can use the CEI / GM Delco kit on a Lucas 45D 'Euro-spec', rather than have to buy a new electronic ignition setup. Is that definite and if so, can anyone explain what needs to be done to achieve it, for example, is the CEI / GM Delco kit simply going to bolt on, or should I say fit, into the Lucas 45D 'Euro-spec',rather than having to perform major surgery. |
| Tom |
| Tom, Your best bet is to try and locate a 45DM4 w/remote amplifier from a wrecking yard. You can always have the distributor's advance re-curved for your application. I have never seen a conversion kit for the 45DM distributor. You certainly do not want to purchase the remote amplifier new from a parts house. Incredibly, Moss sells the remote amp for $229 when it is just a box that contains the $30 HEI module. |
| Steven Rechter |
| Tom. The Lucas 45DM4 was the Constant Energy or CEI version. It has a good reputation for being reliable as opposed to the Lucas 45DE4 or Opus system. What they are talking about with the "bob weights or something" is the basic, centrifugal advance curve. The advance curve for the US spec distributors was set up for emissions performance, not maximum engine power. It may well be possible to have the advance curve of your current distributor reset to one which is more appropriate to your modified engine. Aldon automotive in England should be able to provide some guidance on this. John Twist in the US may also. John has a tech hour at which he takes telephone calls. You might check out the University Motors, Ltd website for the number and see what he has to say, then make your decision based on what you can find out. Les |
| Les Bengtson |
| Many thanks Steven and Les. Reference Steven's comments, I already have a Lucas 45DM4 w/remote CEI amplifier sitting on the garage floor, so I have the raw materials, so to speak, and was rather hoping for a response along the lines of Les's indicating it may be possible to use the originals. If Aldon or John Twist confirm that it may be possible to have the advance curve reset to one which is more appropriate to my modified engine, will the CEI bits just attach as before. I'm assuming they will and any modifications Aldon or John Twist make will be lower down inside the innards of the distributor, or is it more a question of adjusting something, or replacing a component.?? |
| Tom |
| Tom. It is normally a process of changing out springs to give the desired "curve". It may, or may not, require adjustment or replacement of the stop arm which controls the total advance that the distributor can go to. The people who would be doing the work should be able to tell you what they have done in the past and what parts may need to be replaced. Les |
| Les Bengtson |
| IF it can be done, Tom, my uneducated guess is that you would at the least need whatever breaker plate is used in the Dizzy Les and Steve are indicating. I would doubt (but don't know for sure) that the rest of the unit is that different from the Eurospec dizzy except in the matter of the advance curves. This may explain why I have trouble finding points that match the breaker plates for my Eurospec dizzies. Hmmm. This becomes interesting. |
| Bob Muenchausen |
| Do Les's and Bob's comments mean that I would be on the right track if I picked up an old Euro dizzy, and changed the bits over, or is it a bit more complicated than that. Please remember I'm a learner, however my earlier comments 'will the CEI bits just attach as before' seems to be yes because I examined my dizzy and there is a lead coming out of the body, so do I guess right if I assume they will just fit all together.?? |
| Tom |
| Tom, We are all learners, I think, on this one. If someone knows for sure, let us know. I will do some checking on my own. This could be worthwhile. What makes me suspicious is that tho the points I get for my dizzies do work with them OK, the little adjusting nubs on the breaker plate that came with the dizzy which are used to tweak the points, are on the WRONG side for the slot at the end of the points. To me, this makes the breaker plate just a little suspect as to its origin, possibly from one of the later electronic ignition dizzies Lucas made??? This raises some interesting questions and if anyone has access to Lucas parts info etc, it sure would be a help. |
| Bob Muenchausen |
| Bob, Do you mean that if we were able to look at a Lucas parts list for each version, we would be able to ascertain if there was any commonality between the two. They look similar from drawings. |
| Tom |
| Well, Tom, we might get lucky! ;-) I will see if I can't get my local parts house guy to let me look at his books for Lucas dizzy stuff. |
| Bob Muenchausen |
| I too have a CEI electronic ignition on my 79 MGB with the remote module. Does anyone have the part number for the HEI module so that I might keep a spare in the trunk/boot for when it goes out at exactly the wrong time. Thanks! |
| Frank |
| I came across this snippet of info on website http://www.corecomm.net/~ckotting/xref.html Quote: Amplifier Module for the later Lucas Model 45DM Electronic Distributor (The one with the separate finned module.) When you remove the bottom cover of the remote amplifier there is a boomerang shaped plastic thingy. That is the actual amplifier, and it interchanges with the GM X-car (Citation, Phoenix) module. Also fits Fiat Spider and about a dozen other 4 cylinder engines, so it is really common. (Thank you to David Riker from the Spridgets List for this tip!) Available most anyplace: Endquote; Borg Warner Part No:CBE4P given but not sure for what. Also for Bob's continuing investigation, came across website http://www.mgbmga.com/tech/mgb21.htm showing Distributor Specifications, so hope this all moves things forward. |
| Tom |
| The NAPA part number for the amplifier is TP45SB and sells for $22.99 at my local NAPA dealer. It is somewhat boomer rang shaped as stated above. Haven't had a chance to take apart my remote amplifier to see if it is a match. If someone else does let me know. |
| Frank |
| Gentlemen, thank you! I will look at this tomorrow morning!! Let's see what we can do! :-) |
| Bob Muenchausen |
| Bob, Another website which may be of interest, although it is more graphical, than textual. http://www.jag-lovers.org/xj-s/book/Distributor.html Hope it helps your investigations further. I've come across some notes from last year that say some mg specialist had indicated that they could convert my old Fed distributor to a Euro spec for around £70, or say just over $100, however I didn't give it much thought at the time because it seemed to be a similar price to buying a new unit altogether. Also, I didn't raise the prospect of using the original CEI electronics, so if the Fed can be DIY converted at a reasonable cost, and the electronics can be utilized, a major saving is in reach. |
| Tom |
| Frank, TP45SB is the correct NAPA part number for the module. Over the past 25-30 years, GM Delco only made two different HEI modules. One module has four connections and the other has six connections. The parts counter guy will know the part number of the module when you tell him that you want the four connection HEI module. The NAPA module you quoted has four connections and is used in the Lucas CEI system. This module is also used in millions of Chevy's, Oldsmobiles, Pontiacs, Buicks, etc., from the mid seventies to the present. |
| Steven Rechter |
| Has anyone succeeded in fitting the parts from a Euro spec into a Fed spec, and gotten it to work with either the old points or the CEI. If someone's done it already, and is reading this, perhaps they can put everyone out of their misery, and spill the beans. |
| Jack |
| When I switched my 79 California Import (back to UK) to twin SU's (HIFs) I had no end of problems, until I got a standard European distributor (off a UK 79 B). Timing is set at 10 degrees BTDC. I also fitted a Lucas sports coil and Petronix Ignitor, but it ran okay with the points in. It all looks good with no external boxes and is problem free. FWIW I have Mini K&Ns to clear the servo (conical with an offset to the carb intake) and a Falcon Stainless Steel exhaust. |
| Peter |
| From what I have seen, gents, I think what one has to do to make use of the CEI parts is to locate an 1980 CEI dizzy (at least, if not also the electronics box that goes with it). Since the Eurospec dizzies share the same basic distributor body and internal mechanicals with these 45DM4 dizzies, I believe that the breaker plate with the boomerang shaped pick up from a 1980 CEI dizzy "ought" to drop in to replace the OE points. The magnetic collar to trigger the pickup will have to come from a 1980 CEI dizzy and be placed over cam. You still seem to be able to get the OE flash cover, rotor, and cap from VB and Moss and on the surface of things, they look like they ought to fit up with the Eurospec dizzy body. This is somewhat guess work by looking at the catalogs. I will attempt to get my hands on the Factory shop manual for the 75 - 80 MGBs from the library today, but if someone has the factory Parts manual covering that same period, a looksee into their drawings ought to help resolve this issue. As they say on TV, "More to Come!" |
| Bob Muenchausen |
| This is information imparted by a friendly contact, and compares part numbers between the Euro 41610A & 41610B/D, and the 41851A Fed spec. As you can hopefully see, there is much commonality between the two types, except for the 'Range', 'Cover', 'Rotor Arm', & 'Base Plate'. I'm assuming the 41610 series is a typical Euro version to compare the Fed against. Perhaps Peter can look under his bonnet, determine the number on his distributor, and report back. I don't know how the info below will turn out on the BBS, but it's from a spreadsheet, so if you have difficulty making the columns line up, try copying and pasting into Excel, and hopefully that will restore the formatting. Hope Bob can report back that his initial findings are confirmed, so that we can save the expense of buying a new Pertronix unit by using what we have. by the way Peter, how much did it cost.? Part No. 41610A 41610B/D 41851A Model 45D4 45D4 45DM4 Rotation Clock Clock Clock Range 11-13deg 11-13deg 14-16deg Vacuum, Advance 3-11-12 3-11-12 3-11-12 Vacuum, retard 0 0 0 Plate, clamping 421191 421191 421191 Cover DDB108 DDB108 DDB199 Brush and Spring 54423441 54423441 54423441 Rotor Arm DRB104 DRB104 54402072 Contact set DSB108 DSB108 0 Capacitor DCB104 DCB104 0 Insulation Cover 0 0 54427424 Pickup and Base Plate 0 0 DRB133 Base Plate assembly 54425400 60600540 0 Vacuum unit 54428147 54428147 54428147 Dog or gear, driving 420620 420620 420620 O' Ring, oil seal 188639 188639 188639 |
| Tom |
| Formatting didn't work, so here is a revised version of the table. To read this in Excel, first copy into Word, then search & replace all / characters with the tab character, then copy into Excel, and hey presto, it should be in columns. Part No./41610A/41610B/D/41851A Model/45D4/45D4/45DM4 Rotation/Clock/Clock/Clock Range/11-13deg/11-13deg/14-16deg Vacuum, Advance/3-11-12/3-11-12/3-11-12 Vacuum, retard/-/-/- Plate, clamping/421191/421191/421191 Cover/DDB108/DDB108/DDB199 Brush and Spring/54423441/54423441/54423441 Rotor Arm/DRB104/DRB104/54402072 Contact set/DSB108/DSB108/- Capacitor/DCB104/DCB104/- Insulation Cover/-/-/54427424 Pickup and Base Plate/0/0/DRB133 Base Plate assembly/54425400/60600540/- Vacuum unit/54428147/54428147/54428147 Dog or gear, driving /420620/420620/420620 O' Ring, oil seal /188639/188639/188639 |
| Tom |
| Good work Bob, please keep digging, also Tom for those figures, at least I'll be a Spreadsheet expert, if nothing else. Does this mean that to make use of the CEI parts in a 1980 CEI dizzy, I need to get my hands on a Eurospec dizzy, ( model #??), if so, is there just one version, or several. Bob seems to be saying that as they share the same basic distributor body and internal mechanicals, the two types will simply drop in, without any alterations?. Do I assume that the Eurospec dizzy becomes the master, and that the 1980 CEI dizzy is bastardized for the electronic bits, then trashed. Also looking at Tom's data, it does appear as if my earlier question about versions has a valid point, which one is correct. |
| Jack |
| Jack, et. al: That is essentially how it appears to me - that it would be a simple matter of exchanging "breaker plates" and then the electronics on them. The only other odd pieces could be the flash cover, possibly the rotor and cap, and the magnet trigger collar. I would almost bet that the Pertronix collar, if you had one would work as a substitute. I have not gotten to the library to pick up that copy of the factory shop manual yet. Maybe later today. However, if someone reading this has a copy of the Factory Parts Manual which extends thru the end of production (1980), there should be drawings which show us what we want to see. I have a parts manual but mine only goes thru 1976. If that person with the complete parts manual could scan and send one of us the file in Jpeg or some other common format, it would be appreciated. I have a feeling tho that I may see all I need to in the Shop manual. |
| Bob Muenchausen |
| BTW, Tom, how do I convert a Word file into an Excel file?? I did as you said and Excel coughs it up at me as not compatible? I have your info above sitting in a Wd Doc file with the tabs inserted as I think you meant them to be. Maybe you could email me your Excel file? {you can tell I am no PC guru! ;-) } Thanks for digging that info up and formatting it!! It agrees with my own, so I think we are working off the same page here. |
| Bob Muenchausen |
| Bob I used WordPerfect, but the process would be the same in Word. First I pasted the text into my WordPerfect document. Using se |
| jmlema |
| Bob Let me try this again without hiting return!!! I used WordPerfect, but the process would be the same in Word. First I pasted the text into my WordPerfect document. Using search and replace I replaced the / with comma. Then I blocked and copied the text into Excel. Blocking column A I went to Data, Text to Columns. Selected comma delimited and selected finish. I had to move a couple of rows that had a extra column, but otherwise worked fine. There is most likey an easier method, however this does work. You could also skip the word processor step and try pasting directing into Excel the use the Text to Column feature. Jim |
| jmlema |
| Bob I did try to paste directly into Excel and it will work if you use paste special, text. Then block column A and select text to columns under data. I used field type delimited and on the next screen I selected other for the delimiter and entered / as the character. It worked. Jim |
| jmlema |
| I have a CEI unit in my '77B. Did not think too much about it unit this thread. I don't know the history behind the motor. I did purchase a flash cover from Moss and new cap and rotor from my local Roadside Auto. The cap and rotor are KEM parts. The motor ran. I pulled the engine and gearbox this weekend to replace clutch and seals. I will check all the dizzy numbers and post if interested. -mike |
| Mike Zaffarano |
| Can someone go over the advantages of the Eurospec Dizzy over the standard dizzy with the CEI electronic ignition. Thanks! |
| Frank |
| Hello, Bad news I am afraid, my car is in a garage having a touch of work done on the body, so I cannot look under the bonnet. It is a 45D4 Distributor, bought second hand for £15, about US$21, but I cannot tell you the exact series. I do not expect to see the car for a while either as tomorrow I travel to the States for a couple of weeks, then immediately after that a trip to the Middle East. The main difference is the totally different advance curve, as I understand on the California cars the advance only works in 4th gear too, another bit that I removed during the conversion. Sorry that I cannot be of more help at present, but I can confirm that we could not get the car run smooth at all with the standard California '79 ignition set up. The carbs spat; there was no power and so on. Rebuilt distributors over here are about US$140 and most companies will ship to the states, try www.mgbhive.co.uk , that is where my car is and their service is great I highly recommend them. (You could even ask them to have a look under my bonnet/hood- registration SGK 540V.) |
| Peter |
| This is what I found. I have 43DM4 / 41815A stamped on the dizzy but, get this, I have 45DM / 41813A hand engraved above the original stamping. Anyone have a guess as to what this could mean? I know it has all the components of a CEI unit. -mike |
| Mike Zaffarano |
| On the word/wordperfect to excel bit, one way is to use find/replace function in word/wp to insert the column delimiters where you want them and then save as a text file. Excel will read the text file and allow you to select either the appropriate delimiter or to mark in the file where the columns are to start/end. To find/replace with a delimiter automatically you need to use an appropriate character or combination of characters as a marker otherwise you are into manually inserting the column delimiters. Hope this helps. Richard |
| Richard |
| Simple. 1. Select and copy from thread. 2. Paste to Word. 3. Find and replace Find what: / Replace with: ^t 4. Select all and copy 5. Paste to Excel 6. Done |
| Mike Zaffarano |
| Mike Zaffarano's question. According to the Lucas data sheet I'm looking at, they list a 43DM4 and a 45DM4, no 45DM's though. There is a 43DM4 41821A/E, but no 41813A, at least not on this sheet. Again, according to the Lucas data sheet, the 43DM4 41821A/E appears to be a CEI system, so perhaps yours having the earlier number, could have started life as an Opus type, which was converted to CEI. The missing 4 on your number merely seems to differentiate a 4 or 6 cylinder model. |
| Tom |
| Hadn't thought of pasting it directly - you learn a lot from this BBS. Thanks Richard |
| Richard |
| Re problems with sreadsheets, the easiest way to get that Word file into Excel is Open both Word and Excel. Minimize Excel, copy the data from the BBS into Word. Replace all the / with tabs. 'Select All' in Word then , 'Copy' to clipboard. Minimize Word, Maximize Excel. 'Paste' into cell A1, and hey presto, Excel pops it into columns for you. It beats all that messing about with Excel's converters, and yes Bob, I've had the same problem with Excel, crying unable to do it. jmlema, Seattle had better be tasked with shooting round to have a quick word with Bill about compatability, or we could even ask Frazier to ask Daphne if her charming brother could do the honours. If there is a problem ongoing with the sreadsheet Bob, I will e-mail you with it. The Lucas data sheets I'm looking at are ' Publication MRC2 Issue 11/82 ' and show part numbers for the 45 series and an exploded drawing, but as these sheets were faxed to me, they are not brilliant quality, although I will try and scan them, if any help. |
| Tom |
| Mike, If you have a digital camera available, can you take a few fotos of these items?? 1. an overhead view of the "breaker plate" minus the rotor, flash cover, and perhaps the magnetic color as it is mounted in the 45D** dizzy body you have? What I want to see is what this plate for a CEI system looks like, so that I can compare it to the "normal" points type breaker plate used in the generally available "EuroSpec" dizzies. 2. a foto of the magnetic collar. 3. A foto of GM "boomerang" shaped pickup. (I know what they look like, but I would want to see how they are mounted in the alloted space inside this dizzy. 4. a foto of the dizzy showing it from the side showing the Vacuum capsule to one side. If you can do this, please email the files to me and to Tom so that we can take a look at them. It is too bad we do not have a place on this BBS site to share photos, but if necessary, I will set up a temporary page so that other interested folks can share their knowledge on this subject. Thank you, Mike!!!!! Thanks too for the info on creating the chart! |
| Bob Muenchausen |
| Bob, image on its way. Please forward to Tom. Sorry I took so long to respond, I was pulling the flywheel and end plate. -mike |
| Mike Zaffarano |
| Here is a page for sharing photos I just put up. http://hometown.aol.com/akamrmg/MGPhotoShare.html On this page, you folks interested in this particular Electronic ignition set up we've been discussing, will find a preliminary photo from Mike Zaffarano of his 1980 "43DM4 / 41815A stamped on the dizzy but, get this, I have 45DM / 41813A hand engraved above the original stamping." FWIW. |
| Bob Muenchausen |
| I might reget mentioning this, but here go's, I installed an MSD multi-spark system on my 69B about 7 years ago. Though the kit does not claim to work on MGs, or provide instructions for MGs, it works great! I've never had a problem since I installed it. I elected to keep the points type distributor (it was already new). I did need to buy an optional device to load the points so the tach would work (looks like a transformer I don't recall what it was called), but it goes a long ways without changing points and provided a surprising ammount of performance change. I mounted the control box in the hood storage area inside the car just above the battery (this did require splicing the wires for reach on the kit). I chose this location because of the Engine heat, and lack of space up front)The reason I might regret this is I did it 7 years ago, and don't remember the details of the install if someone would ask. Oh, yea, I got this from Summit Racing. I think it was a model 6A (it was not the cheapest, but does not have the rev limiter). Hope this helps! |
| Dennis Hill |
| Thanks, Dennis, that is an alternative several folks have used succesfully, mentioned here on this BBS and seen at many shows. As for the continuing saga of the GM CEI dizzy, there are now fotos up (thanks to Mike Zaffarano!) at the photo page previously mentioned. Let us know what you make of what he has. |
| Bob Muenchausen |
| According to the chap who is helping me on my MG, he thinks that the 45DM4 and the Eurospec dizzy are interchangeable, and believes that this means that the CEI electronics can be transferred between the two. We stripped down a 45DM4 and the weights had 16 ( degrees) stamped on them, the springs were heavy duty, so it looks as though the only difference might be the weights (from memory they are 12-14),and lighter springs in a Euro dizzy. Cannot say if the physical profile (shape) of the weights is any different between the two, as we didn't have a set of Euro dizzy weights to compare. Also, the auto data book my friend used to look up the Euro spec, had details of the advance curve at idle, and several different RPM's. It listed dizzy 41610 as the model version for the 76 on car. I'll put the RPM data on when I receive it. If anyone can comment on the physical profile (shape) of the weights, it may help to resolve the differences which seem to be minor, but important. |
| Tom |
| Tom: Does Mike's dizzy innards look anything like those at the site I set up??? If not, could you send me the same photo shots as I asked of Mike Z??? If you have a digital camera available, can you take a few fotos of these items?? 1. an overhead view of the "breaker plate" minus the rotor, flash cover, and perhaps the magnetic color as it is mounted in the 45D** dizzy body you have? What I want to see is what this plate for a CEI system looks like, so that I can compare it to the "normal" points type breaker plate used in the generally available "EuroSpec" dizzies. 2. a foto of the magnetic collar. 3. A foto of GM "boomerang" shaped pickup. (I know what they look like, but I would want to see how they are mounted in the alloted space inside this dizzy. 4. a foto of the dizzy showing it from the side showing the Vacuum capsule to one side. The Late Bentley Reprint of the Factory manual is a bit hazy on this and no one who might have a copy of the 1980 Factory Parts Manual seems to be forthcoming with any info, graphic or otherwise on this subject. So any photos you can spare, Tom, would be appreciated in trying to scope out the feasibility of this swap. BTW, what is your opinion of the components you see in Mike's dizzy photos??? Are they like your friend's?? Thanks for your help. |
| Bob Muenchausen |
| Bob, I've had a look at those great photo's you and Mike organized, and yes they do look very familiar. The only difference is the number, mine is 41851A, off a 1980. I meant to say on the earlier message that according to the data, the Eurospec as fitted to 76 or later cars with twin SU's, is shown as 41610, and you can see from the earlier parts data that there is a lot of commonality between the 45DM4 41851A and the Eurospec 41610. I may have my hands on a scrap Eurospec dizzy in a few days time, so I may be able to do a physical comparison. A preliminary conclusion my friend came to, and he knows a lot about Lucas, was that a 45DM4 would work if the weights were either modified to allow a Euro type advance curve to occur, and I'm sure he mentioned elongating the slots on the plate, and/or replacing the two equally heavy little springs with a lighter spring. Or using the innards of a Eurospec dizzy. He pulled a very similar spring out of his box, but it seemed to be so thin and flimsey, as to be defective. He thought this was the strength of spring required, for a Eurospec, meaning the 45DM4 has pretty robust springs by comparison. The problem appears to be that Lucas no longer supply parts, and the only source seems to be a restorer, who will not supply parts, only a refurbished unit. Where are they getting their parts from I wonder.? I'll try to get a set of photo's organized, and will e-mail them over to you soonest. |
| Tom |
| Beware, *some* refurbishers may do a good job on the bearings but supply whatever springs (sometimes only one), vacuum capsule and points cam comes to hand first. The max centrifugal advance for the 41851 is quoted at 35 degrees at 4500 rpm. This is double what is quoted for the 41610 at that engine speed, which goes up to a max of 24 degrees at 6400 rpm. The 41851 was also a low compression dizzie whereas the 41610 was a high compression. However the vacuum capsules do seem to be the same. There was a pre-76 version of the 41610 which had ported vacuum whereas the 76 version used manifold. There are usually two springs of different specs to give a 'knee' in the 'curve'. |
| Paul Hunt |
This thread was discussed between 12/03/2002 and 04/04/2002
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