123 ignition gains?

[Hat]

Has anyone done a dyno test of before and after using a 123 distributer?
be interesting to see the numbers, of course depends on how worn the 'before' distributer was, but still..

[arcturus]

Don't know about "gains" but my B20b certainly runs smoother and starts much more easily.If you are thinking about getting one I recommend it.

[beario]

Accuspark is a fraction of the price and fits in your own dizzy mine was £68 for silicone leads,dizzy cap,rotor,accuspark module and a sports coil and 4 plugs...I've always had great results with whatever I've put it in...

[swedishandgerman]

This is an absolute fact. If your standard distributor is in good condition, regardless of whether it's fitted with points or electronic ignition, there will be no gain in BHP on a dyno if the engine's running with a 123

Above 2,500 there is nothing that a 123 offers that will give any more power. Below 2,500 rpm, the advance curve of a 123 is a match of the original distributor

Any improvement in running such as smoothness and cold starting in comparing a brand new 123 with an old distributor would indicate the old unit needed a spruce up and tune up

What a 123 offers is a one unit fits all off the shelf drop in distributor now that you can't get a brand new original distributor. As well, there's a thing that might make a knackered engine idle more smoothly and another feature that will keep a steady timing if you decide to rev the tits off your poor old engine

[Volvo Canadian]

Hi. All-good for a standard engine, but I think once it is modified, most changes will push the advance further ahead, so that is why I went for one. For the expense - I dunno, one would have to dyno it, yes.

[tdz840]

I have a 123 and for the confidence of an all in turn key unit it works for me.
My dizzy had play in the spindle that was visible when turned on the starter motor.
I considered rebushing but one of the bushes was an oiltite bush that I understand is sintered.
Probably all still doable but the 123 as I said was turnkey.
If you're keeping the car definitely a worthwhile mod as the nause with poor condensers and dodgy points is all a thing of the past
Russ

[Amazonjulian]

I agree with Russ. Mines a daily driver and a turnkey car.

[classicswede]

If the engine is standard and you know how to set points then there is nothing wrong with the original setup at all. If you just want to remove the points then fitting any of the breakerless systems will do the job.

I could not recommend the normal 123 dizzy as a value for money unit other than to a owner with zero mechanical skill but in all honesty if you drive a car over 10 years old you should be capable of doing some basic checks and fixes. It is just a lot of money for something that is just new rather than a upgrade.

The 123ignition programmable unit on the other hand is an ideal plug and play solution for modified engines or for use with alternative fuels. Yes it is a lot of money but building a home made programmable system is not cheap either and will take lot longer to fit. You can adjust the advance curves of a standard dizzy but every time you make changes to the engine you would then need to go and change the weights etc on the distributor. This is not a typical diy job and needs some trial and error as where with the 123 just connect to your laptop go for a drive and puch in some numbers and its done.

[Hat]

Mine has minor upgrades, unleaded conversion, K cam and a twin SU conversion, she does run very well, as in no running on, no pinking, and starts easily. It would be interesting to see what is to be gained with the different timing curves.

[swedishandgerman]

Originally Posted by Hat

Mine has minor upgrades, unleaded conversion, K cam and a twin SU conversion, she does run very well, as in no running on, no pinking, and starts easily. It would be interesting to see what is to be gained with the different timing curves.

Is that a B18 or B20?

Just to let you know that each distributor, regardless of what it came out of or whether it's a 123 or not, limits the maximum advance. This should be set at about 34 degrees at about 2,500 rpm. In other words, once the engine has gone above 2,500 rpm, there is going to be absolutely no difference in power, efficiency, torque.

The different advance curves vary the amount of advance at incremental engine speeds up to 2,500 rpm. That means that it affects the smooth running, efficiency and torque throughout the rev range up to 2,500 rpm. If you do a lot of low engine speed driving, then a good advance curve will benefit. If you always drive above 2,500 rpm, the type of distributor in there won't matter.

For the set up that you have there, I would recommend an 003 distributor sourced from a B18B otherwise an 078 distributor from a B20B, but leave the vacuum advance disconnected.

The K-cam opens up your rev range by letting the engine run faster, in very basic terms. Advanced timing is going to make no difference as we're talking of engine speeds well above the max advance of any type of distributor we're talking about here.

If you have a 123 (normal) I would select the B18B setting and disconnect and plug the vacuum advance if you have one.

The advance curve on a single carb or fuel injection distributor or any of the settings on a 123 for anything other than B18B, B18D or B20B give too much advance for the strong mixture characteristics of twin SU's. You need advance for when running carbs like a single Stromberg which goes weak just off partial throttle openings. Twins SU's chuck a load of fuel down the tubes and not so much advance is beneficial.

If you get a 123 tune, I would try to copy the advance curve of a B18B sourced 003 as best as you can and have the max advance set at about 2,500 rpm. Any variation above that will have zero affect on performance. I would experiment with with different advance at idle - you can't adjust that on an old type distributor - in order to achieve a very smooth idle. You could experiment with different advance throughout the low rev range to achieve as much advance as possible whilst completely eliminating pinking. The best way to do this would be on a rolling road where you can record BHP at incremental engine speeds. Highest power is achieved just before pinking, but as soon as pinking occurs, power drops off dramatically.

As above, there are benefits of these distributors if you're not confident with points or get annoyed with having to regularly check or adjust them. A car with poorly adjusted points will never run right. You can get breakerless kits for some Amazon distributors and as far as I know, 003 is not one of them - shame! In which case, if you want electronic ignition with a twin SU set up, then get an 078 distributor and get in touch with Accuspark.