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Ignition systems
The system I have developed came about due to having to run points on the rally car as electronic ignition is banned. Plus I also do not rate many of the systems on the market as they are either cheap rubbish and I would not trust the reliability to get me to the end of a rally or expensive systems where the only thing that can break is the expensive part. They cannot be repaired at the side of the road either. The system has been developed for rallying which usually switches a lot of people off as they think that along with a fairly high cost it is over the top for their daily run around or show and shine weekend fun car. To finish first in a rally, first you need to finish! Reliability was the main driver for the development of the kit.
Some background info.
My imp is a 100 BHP plus. Hartwell 1040 engine running twin 40 Weber’s with an Andy Jones of Shrigley Engineering special cam shaft. It does not produce power much beyond 8800K but I regularly rev it to 10K and sometimes beyond as it will take it and it is quicker than a shift up and back down the box between corners over a short distance. There are Videos on YouTube of the car, search mike dent rally imp and you will see the grief the car takes.
Getting back to the IGN system. I need high revs without points bounce, this was the first area I struggled with in the days of running a well-known brand gold coloured coil, new old stock condensers, special plug leads (I am trying not to name brands but trust me if you have thought of a brand I have tried it). I have the 43D distributor this is the vacuum less version of the late imp 45D distributor but also has a bolt in points plate (some late imps had the self-tapping screw in the slot in baseplate to clamp it in place which is a poor design) .
High revving 32 OZ points always used to be available from the mini cooper S unfortunately the mini uses a 23/25 D distributor as per earlier imps, again 23D being vacuum less only found on competition engines and some fast road cars like Lotus Cortina’s.
I had to make a decision, convert back to early imp distributor so I can run the cooper S points and get rid of the points bounce or stick with the 43D dizzy and get the points to fit the baseplate, I fabricated an adapter plate and tried the points and we had a result, big revs consistently. So onto the next rally and we discovered another problem when we smashed the distributor cap to pieces. Thoughts at the time were a rogue stone but on closer inspection at home the rotor arm blade was bent so the cap touched the rotor and something had to give. During this inspection I noted grey powder like substance on the distributor top edge and the bottom edge of the cap. This was from the cap oscillating due to revs and engine vibration. I fitted a new cap and gave it a twist; I could actually unclip the cap by rotating it. This is what happened at high revs over the rough surface. Solution was to go to a 23/25D distributor as the caps fit so much better. Thoughts at this time were around also getting a bigger spark so I invested in every type of competition coil, rotor arm, points, plug leads, condensers that I could find, having spent a fortune all were tried and tested at work with people who understand electricity much more than me and then actually tested on the car.
In the end the chaps at work recommended an industrial capacitor so I made a test rig at home and tested with a 40 Kv coil charging and discharging at an equivalent of an imp revving at 8K and left it for a week. This proved the coil I had chosen and the condenser (capacitor) they had chosen were reliable, I even warmed them with hot air guns to above any temp I had recorded in the engine bay and strapped the condenser to a vibrating plate. I cut open as many condensers as I could get my hands on, NOS (New Old Stock i.e. Parts from auto jumbles etc. That were as old as the imps) proper major brand name items. I bought a few new ones as well. All were tested and all failed, most of them before we applied heat or vibration. The main reason for NOS failures was from the insulation material breaking down and disintegrating it was vibration that accelerated this failure. I put this down as age related so whilst the parts were previously manufactured to a higher quality the material condition degraded over time. The new items were just rubbish from the start with poor quality materials and a very economic construction I gave up testing them as they would not last long enough to allow me to give them a hard time.
So I had a coil and condenser that worked, I have had points re-made with 32 oz spring and proper high quality plastic heels, good quality contact material and reliable spring material. In the end I settled for the 43D distributor as you can buy a side exit cap that bolts on so this solved the movement problems and allowed for neat plug lead installation.
To fit the above you need to build the engine with number one plug firing in the correct position this is achieved when distributor and oil pump drive are matched, so not any easy task to do on your car that is running and on the road now. It needs to be set up with number one plug being top right as you look into the engine bay this means number 3 lead is below and can run parallel with number 4 and number 2 is on the top left parallel to number one. All neat, tidy and short.
For those that do not go on the forum here is an exert from a post I contributed about unreliable condensers
Old coils when they were new i.e. 0n your imp in the 60's 70's they were manufactured with good quality oil and copper windings, modern versions use re-cycled oil and re-cycled copper of lower grade, this is to reduce costs so that they can be sold on e-bay for the cheapest price. The original coils could cope with the oil not covering the copper windings due to being mounted horizontally and on a road car the small amount of extra stress did not really cause problems. Use a modern coil horizontally and on a rally car they fail, this includes many performance coils especially the gold coloured ones that used to be the coil to fit to any fast road or rally/race car.
I had a hand in manufacturing rotor arms that have the correct amount of insulation material to cope with the big spark from the high powered epoxy filled coil. Again NOS appear to lose the ability to cope with a big spark voltage with age, New tend to suffer the same due to the resistance material being used (this is the expensive bit) so they tend to arc at the thinnest point i.e. rivet that holds the brass blade on, due to the rally car high revs I have also split the rotor arms in two halves and spat the blades off (centripidal? centrifugal force). I bought all the rotor arms available from every source i could find inc what i suspected were copies of the recently manufactured items, the distributor doctor now engraves his DD due to cheap copies being made just coloured red as this was the colour used to show that they were newly made out of good quality material. I won't list whose were good and bad as that could get me in trouble but the type i use on my rally car were obviously the best out of the ones i tested.
I repeated all above testing for points and had the heels made from good quality material so they did not wear so fast. I chose a 32 oz spring to cope with the revs on the rally car.
Thanks to Dave Lane who has kindly tested the kit on his Singer, Dave and the singer were chosen as it is well documented that the car is looked after with attention to detail and is used regularly. Dave’s exploits with setting up the SU carburettors has been experimental and this was achieved by starting with a good ignition system. My thoughts were if I can make the best running imp I know of run better then I know the ignition system is good for road cars. I did not really have any doubt but had no real world evidence that there could be an improvement on a standard engine.
The system is proven on my car and many thanks to Dave Lane for testing it on a road going car and giving me such detailed feedback.
25/23D Kit £225
43/45D Kit £245
Incs postage packing and delivery to UK.
The system I have developed came about due to having to run points on the rally car as electronic ignition is banned. Plus I also do not rate many of the systems on the market as they are either cheap rubbish and I would not trust the reliability to get me to the end of a rally or expensive systems where the only thing that can break is the expensive part. They cannot be repaired at the side of the road either. The system has been developed for rallying which usually switches a lot of people off as they think that along with a fairly high cost it is over the top for their daily run around or show and shine weekend fun car. To finish first in a rally, first you need to finish! Reliability was the main driver for the development of the kit.
Some background info.
My imp is a 100 BHP plus. Hartwell 1040 engine running twin 40 Weber’s with an Andy Jones of Shrigley Engineering special cam shaft. It does not produce power much beyond 8800K but I regularly rev it to 10K and sometimes beyond as it will take it and it is quicker than a shift up and back down the box between corners over a short distance. There are Videos on YouTube of the car, search mike dent rally imp and you will see the grief the car takes.
Getting back to the IGN system. I need high revs without points bounce, this was the first area I struggled with in the days of running a well-known brand gold coloured coil, new old stock condensers, special plug leads (I am trying not to name brands but trust me if you have thought of a brand I have tried it). I have the 43D distributor this is the vacuum less version of the late imp 45D distributor but also has a bolt in points plate (some late imps had the self-tapping screw in the slot in baseplate to clamp it in place which is a poor design) .
High revving 32 OZ points always used to be available from the mini cooper S unfortunately the mini uses a 23/25 D distributor as per earlier imps, again 23D being vacuum less only found on competition engines and some fast road cars like Lotus Cortina’s.
I had to make a decision, convert back to early imp distributor so I can run the cooper S points and get rid of the points bounce or stick with the 43D dizzy and get the points to fit the baseplate, I fabricated an adapter plate and tried the points and we had a result, big revs consistently. So onto the next rally and we discovered another problem when we smashed the distributor cap to pieces. Thoughts at the time were a rogue stone but on closer inspection at home the rotor arm blade was bent so the cap touched the rotor and something had to give. During this inspection I noted grey powder like substance on the distributor top edge and the bottom edge of the cap. This was from the cap oscillating due to revs and engine vibration. I fitted a new cap and gave it a twist; I could actually unclip the cap by rotating it. This is what happened at high revs over the rough surface. Solution was to go to a 23/25D distributor as the caps fit so much better. Thoughts at this time were around also getting a bigger spark so I invested in every type of competition coil, rotor arm, points, plug leads, condensers that I could find, having spent a fortune all were tried and tested at work with people who understand electricity much more than me and then actually tested on the car.
In the end the chaps at work recommended an industrial capacitor so I made a test rig at home and tested with a 40 Kv coil charging and discharging at an equivalent of an imp revving at 8K and left it for a week. This proved the coil I had chosen and the condenser (capacitor) they had chosen were reliable, I even warmed them with hot air guns to above any temp I had recorded in the engine bay and strapped the condenser to a vibrating plate. I cut open as many condensers as I could get my hands on, NOS (New Old Stock i.e. Parts from auto jumbles etc. That were as old as the imps) proper major brand name items. I bought a few new ones as well. All were tested and all failed, most of them before we applied heat or vibration. The main reason for NOS failures was from the insulation material breaking down and disintegrating it was vibration that accelerated this failure. I put this down as age related so whilst the parts were previously manufactured to a higher quality the material condition degraded over time. The new items were just rubbish from the start with poor quality materials and a very economic construction I gave up testing them as they would not last long enough to allow me to give them a hard time.
So I had a coil and condenser that worked, I have had points re-made with 32 oz spring and proper high quality plastic heels, good quality contact material and reliable spring material. In the end I settled for the 43D distributor as you can buy a side exit cap that bolts on so this solved the movement problems and allowed for neat plug lead installation.
To fit the above you need to build the engine with number one plug firing in the correct position this is achieved when distributor and oil pump drive are matched, so not any easy task to do on your car that is running and on the road now. It needs to be set up with number one plug being top right as you look into the engine bay this means number 3 lead is below and can run parallel with number 4 and number 2 is on the top left parallel to number one. All neat, tidy and short.
For those that do not go on the forum here is an exert from a post I contributed about unreliable condensers
Old coils when they were new i.e. 0n your imp in the 60's 70's they were manufactured with good quality oil and copper windings, modern versions use re-cycled oil and re-cycled copper of lower grade, this is to reduce costs so that they can be sold on e-bay for the cheapest price. The original coils could cope with the oil not covering the copper windings due to being mounted horizontally and on a road car the small amount of extra stress did not really cause problems. Use a modern coil horizontally and on a rally car they fail, this includes many performance coils especially the gold coloured ones that used to be the coil to fit to any fast road or rally/race car.
I had a hand in manufacturing rotor arms that have the correct amount of insulation material to cope with the big spark from the high powered epoxy filled coil. Again NOS appear to lose the ability to cope with a big spark voltage with age, New tend to suffer the same due to the resistance material being used (this is the expensive bit) so they tend to arc at the thinnest point i.e. rivet that holds the brass blade on, due to the rally car high revs I have also split the rotor arms in two halves and spat the blades off (centripidal? centrifugal force). I bought all the rotor arms available from every source i could find inc what i suspected were copies of the recently manufactured items, the distributor doctor now engraves his DD due to cheap copies being made just coloured red as this was the colour used to show that they were newly made out of good quality material. I won't list whose were good and bad as that could get me in trouble but the type i use on my rally car were obviously the best out of the ones i tested.
I repeated all above testing for points and had the heels made from good quality material so they did not wear so fast. I chose a 32 oz spring to cope with the revs on the rally car.
Thanks to Dave Lane who has kindly tested the kit on his Singer, Dave and the singer were chosen as it is well documented that the car is looked after with attention to detail and is used regularly. Dave’s exploits with setting up the SU carburettors has been experimental and this was achieved by starting with a good ignition system. My thoughts were if I can make the best running imp I know of run better then I know the ignition system is good for road cars. I did not really have any doubt but had no real world evidence that there could be an improvement on a standard engine.
The system is proven on my car and many thanks to Dave Lane for testing it on a road going car and giving me such detailed feedback.
25/23D Kit £225
43/45D Kit £245
Incs postage packing and delivery to UK.