Quality ignition components

[Jonny-Jimbo]

Hi all,

I recently took my 2500 Mk1 down to Bicester Heritage for the Sunday Scramble, and whilst the car cruised 'okay' it wouldn't accelerate. So I couldn't drop a cog and floor it to overtake. The car would cruise up to speed (managed to get to 85, gradually), but it couldn't accelerate hard.

By the fact the car would cruise at a comfortable speed, but couldn't accelerate hard, I'm wondering if the issue is spark related rather than fuel? The issue also got worse when the engine was up to temp, which happened on RBRR too. Maybe it's the condenser or coil breaking down when hot? I have a few spare coils knocking around I can use, but does anyone have any ideas on condenser? I have heard good things about the ones Dizzy Doctor supplies, but he/she/they NEVER respond to my emails. I've tried to contact them quite a few times but no luck.

Does anyone know if they have an active online shop now or a phone number I can call them on? Chris Witor's shop lists 'dizzy doctor' but when I ordered them they didn't have the 'DD' logo and came in a Lucas box which makes me think they're not genuine!

Not trying to say this is something Chris has done himself, it could be his supplier etc, but either way, I don't see why DD items would come in Lucas branded boxes!

[glang]

Hi JJ, I know you must have previously thought about electronic ignition but isnt it the answer? One set of points for 6 cylinders is asking a lot and I was always fiddling/inspecting/cleaning wondering if they were causing problems so I replaced em with a cheapy in-distributor unit and have never worried again. At the selling price you can keep a second unit spare if youre concerned about reliability.....

[Jonny-Jimbo]

I've been through that a few times before on here and elsewhere and I have never had success with electronic ignition. Mainly because if it fails it usually means the car is just plain dead and it's hard to differentiate between a knackered wire or a whole unit. I've tried a few different types, and I always come back to points being more reliable over all. Plus it seems daft to me to say 'fit electronic ignition, and keep a set of points in the glove box just in case' - why not just fit points and then have a set of points in the glove box 'just in case'.

So yeah, thanks, but I'll stick with points - or if no-one knows how to get a hold of this Dizzy Doctor person I'll consider a 123 dizzy etc if funds allow.

[RobPearce]

JJ,
Many years ago I fitted an electronic booster to a Dolomite that was prone to burning points rather badly. It was a dirt cheap kit from Maplin, which I potted for water proofing (can be done with silicon sealant or epoxy or GRP resin, or pay loads for the proper stuff). This completely fixed the wear problems and significantly improved the engine responsiveness. It also ran reliably for longer than the rest of the car! Also, doesn't require a condenser (because it has a decent quality capacitor built in).
I agree, though, that I've come across enough people with failed Lumenitions that I'd be cautious.

[JohnD]

The contact breaker points system for ignition, AKA the Kettering system (after Charles, not the town) was first fitted to Cadillacs in the 1910s, and was an enormous improvement on what went before.    But the points do take a battering, wear out and need adjustment and/or replacement every 3-6K.  That's why moderns went over to electronics, beginning in the 80s.  
Without a Condensor  they wear out more quickly, and the spark quality is a little less, but I don't think that that could have the bad effect you describe, JJ.  More likely, you have dizzie shaft/bearing wear and variation in the timing, or just points bounce at high revs.   Check with a timing light, which will show the timing marks jumping about.

The 'electronic ignition' that can be added to our cars represents the next stage after Kettering, in that the CB is replaced by an optical or Hall Effect sensor, and a box of electronics, an integrated circuit that uses two transistors in a Darlington pair (after Sidney, not the town!)  as a switch to do the same job.   Whichever sensor, they are non-contact, never wear out, and in my high intensity experience of racing, the kit is extremely reliable.  Best of all, they work right up to the highest revs you would ever use (7K+)

Can't speak of a Maplin DiY kit, but Lumenition.   I'd go for that, JJ!

The part that Dizzie Doctor supplies that excels is the Red Rotor Arm.    There were some very poor copies about a while ago, and DD came up with high quality ones.   I fear the colour has nothing to do with it, but RED parts have to make you go faster!

John

[Hogie]

Hi JJ,
          give Martin (Dizzy Doc) a call  http://www.distributordoctor.com/contact.php

Roger

[glang]

Quoted from Jonny-Jimbo

I've been through that a few times before on here and elsewhere and I have never had success with electronic ignition. Mainly because if it fails it usually means the car is just plain dead and it's hard to differentiate between a knackered wire or a whole unit. I've tried a few different types, and I always come back to points being more reliable over all. Plus it seems daft to me to say 'fit electronic ignition, and keep a set of points in the glove box just in case' - why not just fit points and then have a set of points in the glove box 'just in case'.

So yeah, thanks, but I'll stick with points - or if no-one knows how to get a hold of this Dizzy Doctor person I'll consider a 123 dizzy etc if funds allow.

I wonder if aftermarket ignition units are still failing early or maybe their reliabilty has improved as in other automotive electronics cos as I say mine has been fit n forget.....

[Nick Jones]

If you experience repeat failures with electronics (ignitions or otherwise) in old cars, you probably have a crappy old Lucas ACR alternator with an even crappier Chinese regulator fitted that frequently spikes to 22v or more.  Hard to detect and they don't all do it but I know some of them do as I could see it on my Megasquirt datalogs.  Gave up and fitted a more modern Bosch instead.

Nick

[glang]

good ol original dynamo and mechanical regulator on mine but with a monster battery that seems to even things out!

[Rosbif]

I've been running Acuspark with dynamo and (as far as I know) standard regulator for 2 years now without the car missing a beat.

As for John D's comment about RED parts, no wonder my 13/60 seems quick it is dark red (wink)

[bxbodger]

I fitted an Aldon ignitor getting on for ten years ago now, because I couldn't get decent points/condenser. It's worked flawlessly, with a distributor doctor arm. I have also used a cheapo unit in my Metro, which failed on me and it's now back on points. The Aldon unit seemd to be built to a quality level, the cheaper ones knocked out by accuspark, britpart, etc, seen to be built down to a price. They're like chalk and cheese.

[glang]

Even cheap electronics should be reliable by now but of course cooling is critical so maybe installation and the use of the heat transfer paste is important.....  

[daver clasper]

Hi

Talking fuel. Could/does, hard acceleration require more than high speed running?. Also a man with your cut of jib, would have full dashpots (if carbs), I guess.

Dave

[JohnD]

Transiently, yes.
That's what the dashpots are for, they are as an accelerator pump, to delay the rise of the piston ad opening of the jet with a thinner part of the needle in it.
Sounds contrary, but the lower piston means that the airflow is faster at the venturi, the bridge where the jet is, and by Bernoulli, the pressure falls so more fule sucked out.
This richens the mixture until the piston rises to a new, steady height, when the mixture returns top stoichiometric.
This richer mixture provides more power during acceleration.

Of course, while fast running, more air enters the bores, so more fuel used, but it's no longer richened.
The problem with Pi is that it doesn't have this, so is normally set rich, unless you want economy and reduced perfomance.
John

[RobPearce]

John is right but the transient effect is short-lived, while hard acceleration also usually involves more throttle than high speed cruising, hence more fuel. Actually, the dashpot enrichment isn't really there to put more fuel into the engine, as such. It's to put more fuel into the manifold to make up for the manifold holding on to most of it and starving the engine. The PI system injects much closer to the valves, so its lack of enrichment isn't nearly as horrid as it would be on a TBi or carb. The original Bosch K-jetronic also lacked any acceleration enrichment mechanism but was metered off an air-flow flap before the throttle (which meant before the plenum) and this "advance warning" was enough to do the job.

[Nick Jones]

Going back to your original problem, have you tried pulling the choke out and then hoofing it?

If it then pulls well and continues to pull it implies you have the wrong needles fitted (exhaust mods and/or filter mods render the OE needles too lean).  If it pulls better initially then dies off it could be that the fuel supply is marginal and the pump is barely keeping up with demand at cruise and has no more to offer.

Weak ignition could make things worse.  Is it just "flat" or does it actually miss?

Nick

[StagNL]

I too had (may still have to a point) similar symptoms.  Anything above 60km/h and it was flat and didn't want to pull.  Pulling choke out helped a bit so I though fuel.  But the ignition needs to be good too. The condenser had recently failed and the timing had drifted off a degree. The points while relatively new were burning.  Valve clearance had also gotten a tad tighter.  All these little variations caused huge perrformance drop.  Carbs still need tending to as they are not yet right....

Julian

[Jonny-Jimbo]

Quoted from Nick Jones

Going back to your original problem, have you tried pulling the choke out and then hoofing it?

If it then pulls well and continues to pull it implies you have the wrong needles fitted (exhaust mods and/or filter mods render the OE needles too lean).  If it pulls better initially then dies off it could be that the fuel supply is marginal and the pump is barely keeping up with demand at cruise and has no more to offer.

Weak ignition could make things worse.  Is it just "flat" or does it actually miss?

Nick

Nick, it feels like it's actually 'missing' as the car stutters and actually slows down. I completely forgot the old choke trick (calm down Ferny...), but as AJ is at her families this weekend I'll have two whole days to play. If there's a chill in the air on Sunday morning I may take the Mk1 for a blatt down the Fosse Way (Roman road, so nice and straight), and when it misses I'll try tugging the choke and see what happens. There is a good gap on the points, and the spark is strong on it. I'll try and borrow a decent timing light too so I can double check that.

I shall report back over the weekend.

[Nick Jones]

Also check the earth wire on the distributor baseplate - if that's iffy you get strange things happening as the vac advance operates and things make and break.

Nick

[Jonny-Jimbo]

Cheers Nick, that'll be an easy one to assess - I'm in the midst of electrics on the Volvo, so whilst I have all of that kit out I may as well check on the earth wire too.

[Jonny-Jimbo]

Took the 2000 out today fairly early for a good 50 mile round trip, but the issue was manifest still. I did the test of pulling the choke out and it didn't make any difference, so I'm thinking it's certainly ignition related rather than fuel?