17 replies to this topic

[erica]

The Lucas 29D4 distributor on my 1974 clubman is on its last legs, and i was thinking of replacing it with a Bosch instead.

Is this a good idea?

And does the bosch fit directly on like the last one did, or will i have to make any other changes?

Thanks
x

Edited by erica, 17 November 2008 - 07:03 AM.

[rozzer!]

personally would spend the pennies or dollars on another lucas. you know its going to work rather than require modification and more parts.

[998dave]

You have to be more specific over this Bosch one, they'll have many different dizzy's for all sorts of cars, I doubt you'll find one that simply slots into place...

I don't think there's a Bosch dizzy as standard fitment on any mini's, unless you know something I don't...?

Dave

[Guess-Works.com]

and not forgetting that an A series Dizzy is designed to go anticlockwise...

[dklawson]

Bosch from certain earlier BMWs are supposed to be possible. As mentioned above, you have to pay attention to the direction of shaft rotation. This is easily determined just by looking at the direction the vacuum advance canister points. If it points the same direction as the Lucas, it rotates the right direction. Of equal importance is finding one that has the right diameter and length to fit the A-series block. Regardless, you'll have to make or modify the drive dog on the Bosch unit.

A much more common swap is what I'm running, a Hitachi distributor from a 1.6L (inline) Nissan engine. You have to modify the clamp base to work on the A-series and you have to transfer the drive dog. That's about it. The benefit of this swap is you get inexpensive electronic ignition that's virtually bullet-proof.

You're in OZ? Are you a member of any of the OZ forums?

[erica]

Thanks everyone

You have to be more specific over this Bosch one, they'll have many different dizzy's for all sorts of cars, I doubt you'll find one that simply slots into place...

I don't think there's a Bosch dizzy as standard fitment on any mini's, unless you know something I don't...?

Dave

Sorry i dont know any specifics
im basically just going on what a british car mechanic has told me. i just thought i would invetigate further

Bosch from certain earlier BMWs are supposed to be possible. As mentioned above, you have to pay attention to the direction of shaft rotation. This is easily determined just by looking at the direction the vacuum advance canister points. If it points the same direction as the Lucas, it rotates the right direction. Of equal importance is finding one that has the right diameter and length to fit the A-series block. Regardless, you'll have to make or modify the drive dog on the Bosch unit.

A much more common swap is what I'm running, a Hitachi distributor from a 1.6L (inline) Nissan engine. You have to modify the clamp base to work on the A-series and you have to transfer the drive dog. That's about it. The benefit of this swap is you get inexpensive electronic ignition that's virtually bullet-proof.

You're in OZ? Are you a member of any of the OZ forums?

Thanks for the reply. i was pretty sure i'd struggle to get one to fit stright on without mods.
yeah im in Australia...i registered for ausmini forums about 6 months ago, and they still haven't registered my account.

[icklemini]

then theres the issue of advance curves that'll be wrong. etc..

am sure there are plenty of people in the uk that have a lucas distributor they could sell you...

[dklawson]

The advance curves being "wrong" is not as big an issue as you think. The original distributor represents a compromise as it weighs in manufacturing tolerances, fuel quality, and variations between engines. For optimum performance a distributor has to be custom 'tweaked' by a professional, typically in conjunction with a dynamometer. I'm no expert and don't claim to be. However, in most instances (on the street) you probably wouldn't notice the difference between the original Lucas distributor, a Lucas distributor from some other A- or B-series engine, or one from something Japanese or German. On the track... that would be all together different. For more information on this, Google for Marcel Chichak. He is the person who documented the Hitachi distributor swap, maintains the largest publicly circulated database of Lucas distributors, developed the advance curves in the 123 distributor, and comparatively studied the advance curves of other 4-cylinder distributors against Lucas dizzys used in the Mini.

Erica, you have a PM from me.

[icklemini]

Thanks for the info... from expereince of modifying distributors myself, you will find that yes there is a huge range of tolerancies to contend with - and often they are 'wrong' for the engine coming from the factory..

You will and do notice this on a road engine more than a racer of course - as racers tend to run at a rev range where the advance is all in...
The wrong curve on a road car is noticable.

Advice i gave above was pragmatic based on the circumstances... certainly not intended to cause upset to the long term residents.

thanks,
Dave

[makka]

Bosch from certain earlier BMWs are supposed to be possible. As mentioned above, you have to pay attention to the direction of shaft rotation. This is easily determined just by looking at the direction the vacuum advance canister points. If it points the same direction as the Lucas, it rotates the right direction. Of equal importance is finding one that has the right diameter and length to fit the A-series block. Regardless, you'll have to make or modify the drive dog on the Bosch unit.

A much more common swap is what I'm running, a Hitachi distributor from a 1.6L (inline) Nissan engine. You have to modify the clamp base to work on the A-series and you have to transfer the drive dog. That's about it. The benefit of this swap is you get inexpensive electronic ignition that's virtually bullet-proof.

You're in OZ? Are you a member of any of the OZ forums?

G'day, do you know what model Nissan engine the Hitachi comes off? I might grab one and take it back home and see if I can mod it to fit Erica's car

[erica]

too late....got a bosch one on.

[makka]

too late....got a bosch one on.

I know, but it will give me something to do.

On a side note, do you know why Poms drink warm beer?

Because they have Lucas refrigerators!

[dklawson]

Makka, PM Erica. I sent her the name of my contact in OZ who has done several Hitachi conversions. He can tell you which OZ market Nissans to look for. I'm sure that even though the cars were the same... they called them something different in the U.S. and in Australia. Me... I look for the early 1980s Nissan Pulsar and Sentra distributors.

[makka]

Makka, PM Erica. I sent her the name of my contact in OZ who has done several Hitachi conversions. He can tell you which OZ market Nissans to look for. I'm sure that even though the cars were the same... they called them something different in the U.S. and in Australia. Me... I look for the early 1980s Nissan Pulsar and Sentra distributors.

Cheers mate, I will just ask her when I get back home on the weekend, she is my little sister.

we have pulsars here too, I will head over to the wreckers today and see what I can find

[dklawson]

Makka, here's some additional information that may help you:
http://www.starchak....dfs/hitachi.pdf
(From Marcel Chichak).
and a paraphrased link to the same...
http://www.niksula.h...iy/alien/dizzy/

Expect the Hitachi diaphragm in the vacuum advance unit may be torn. Also, plan on taking the Hitachi apart. While it's apart, look at the bearing assembly under the advance plate. These are typically a plastic ring with "ears" to hold three 3mm diameter balls. The plastic rings are sometimes broken and you'll find the balls floating around inside the dizzy. I have made replacement rings out of thin aluminum with simple holes drilled to capture the balls. It's not a hard fix and the advance plate moves better with the balls in place.

My friend in OZ should be able to provide you all the information you need but don't hesitate to contact me if you have questions.