13 replies to this topic

[Goacher65]

In the process of finishing off a few winter jobs on the mini and looking at what the best distributor might be before taking it to the rolling road to get it tuned. I currently have a 45D with Aldon Blue ignitor kit in it. The engine is a A+ Metro engine, Kent 276, 1.5rollers, lightened flywheel, Bill Richards 'Rally' spec head. Now when Bill set up the engine for me, he just blocked the vacuum off and said "you won't need that". Does this have any effect to power as opposed to economy and idle?

 

With it as it's set up currently, when indulging in 'spirited' driving, when putting my foot flat at 4k-ish RPM, it hesitates slightly before picking up. A friend of mine, from Mk1 Escort background, said it could be worth getting an old distributor with a weighted advance system in it and transferring it over.

 

Is there anyone on here who knows how feasible this is, can I still use the blue points ignitor kit in it, will it fit into the same body as the 45D, and finally, which is the best distributor to buy to pilfer the bits out of?

 

If it's likely to be possible to remedy the problem with a rolling road set up, then I'm happy to stick with what I've got, but I don't want to spend £120 on a session then change bits after and have to re do it all. Equally, I don't really want to have to go out and buy a new distributor which I can't put the Aldon kit in, as i've only done about 3k miles with this kit.

 

Thanks in advance...

[nicklouse]

the VAC is only there to improve economy. your dizzy is already a weighted one.

 

but does the advance that it gives suitable?

 

has it been set up (carb and ignition) on the rollers?

[KernowCooper]

The vacuum advance also improves drivability on the road on light throttle as not only does it increase mpg it also increases torque when driving on a light throttle. All cars used on the road will benefit from vacuum advance, only race cars benefit from none.

[Goacher65]

Nicklouse- no as yet it hasn't been set up on the rollers. Is the weighted advance something that can be altered or is it set for the distributor? It hasn't been set up at all on rollers, only by Bill Richards using his knowledge and experience, but not under load or power.

 

KernowCooper- thanks for that, the plan is to use the car for Rally/Autotest events locally, but also gets used on the road from time to time. I shall ask the chap at the rolling road what he recommends when I take it up there.

[nicklouse]

yes the weights can be changed (as can the whole base plate) as can the springs. and you can add weld to them to reduce the amount they move or remove material increase the amount they move.

 

any rolling road operator should be able to do this.  the only thing you need to consider is Vac or not. is not you can change the base plate or lock it in place so it does not move. just removing the Vac valve is only half as the base plate would now be able to rotate with no control. it need locking in place. Oh then you will need a piece to block the hole where the vac valve was with a tag to locate the cap (if that type of dizzy).

 

I would do away with the vac advance my self.

[tiger99]

If you want to be able to make changes easily, and eliminate a few other problems, you really should be looking at a mappable electronic system, not a crude mechanical system. It will end up cheaper, as it can be instantly tweaked on the rolling road, without dismantling and fiddling about with weights and springs.

 

Here is one such system. There may be more:

 

http://www.tjhafner.com/MegaSpark.html

[Alex_B]

Another option is a 123/Tune distributor, the newer 123's can be fully tuned using a laptop rather than using the pre selectable maps as per the last unit. 

As mentioned above it allows much faster changing of advance curves at 8 points in the rev range, which will save considerable time and money reweighting a mechanical dizzy. I have fitted a few of these to customers cars and its a big improvement in tuneability. You can also run two maps on a switch so you could set it up for both 95 and 98 octane fuel if you wish. But should be fitted and then rolling roaded to ensure you have the correct curve for your engine.

http://www.minispare.../C-27H7775.aspx

 

Edit: These units also have a vac connection so you can set up your mechanical advance as well as vac advance to your requirements. 

 

Edited by Alex_B, 30 January 2016 - 01:08 AM.

[landsurveyor]

My car was set up by Sigma engineering in Dorset, and they also advised and blocked off the vac connection on a rolling road session. Seems to drive well without it connected but I don't know about the fuel economy difference? I have just left mine blanked off.

[KernowCooper]

You should walk away from any rolling road operator who tells you or blanks off your vacuum advance on a road car.

[cal844]

You should walk away from any rolling road operator who tells you or blanks off your vacuum advance on a road car.

+1

[Craig89]

I was also advised the same when having my car rolling roaded at Southam, and they come highly recommended

[KernowCooper]

They may be recommended but the statement still stands, if its a standard road car and your standard distributor is in good condition and they advise disconnecting the vacuum advance walk away, If you run a Aldon Yellow like I do I still run Vacuum advance as it a road car.

 

Those who were advised to disconnect it, reconnect it and go for a drive where your crusing on a light throttle, you'll be surprised !

[Craig89]

They may be recommended but the statement still stands, if its a standard road car and your standard distributor is in good condition and they advise disconnecting the vacuum advance walk away, If you run a Aldon Yellow like I do I still run Vacuum advance as it a road car.
 
Those who were advised to disconnect it, reconnect it and go for a drive where your crusing on a light throttle, you'll be surprised !

It is an Aldon yellow. Engine is fast road spec 1293cc. 78bhp ATW. I remember the operator saying with the vac advance connected it was getting to much advance at low RPM, 50 degrees i believe. Then it was dropping down as the vacuum was lost then climbing back up as the RPM got up. He basically said it wasnt a very smooth curve.

Now dont shoot the messenger hear, im just going by what he said. I was always of the understanding to run a vac adv in a road car. My car does drive well though and im getting a decent fuel mileage so im happy

[Goacher65]

As mentioned previously in this thread, it's not a road car. It's intended to be a competition car, so driving along at light throttle, and fuel economy isn't my biggest concern. I think Nicklouse has covered that the mechanical advance is adaptable, it's just if there is a way of putting interchangeable weights in there instead of altering the current ones, whilst retaining the Aldon Blue kit.

 

I know that mappable ignition is an option and is easier to change, but this adds the cost which I'd hoped not to need to do. Surely once the advance is set up correctly on the rolling road there will be no need to adjust it regularly going forwards, and the only adjustment would be the static advance by twisting the dizzy, if I was to remove the distributor for any reason. Even if you had mappable ignition, surely once it's mapped correctly, you don't change it regularly. I do only use V-Power too.