Distributor Testing

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Mike
Nurse, I think I need some assistance
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Location: Hampshire

Distributor Testing

Post by Mike »

Because so many engines Neil Bainbridge was getting in to test on his dyno had distributor problems, Neil has invested in a distributor testing rig.
It's a great piece of kit which allows him to run all sorts of tests to correctly set the dizzy and optimise it's performance.

With points distributors you can set the phasing correctly for the number of cylinders, plot the advance and dwell curves and from them see if you
have points bounce or a worn cam for instance and fluctuations in the dwell through the rev range can show up worn bearings. Twin spark dizzy's
with 4 set's of points, 2 for each bank become a lot easier to set up as you can see exactly what each set is doing. You can also see how the
operation of the bob weights works, the graphs will show if they are sticking or need lubricating as well as reading the exact amount of advance.

With the Porsche wiring harness you can unplug it from the car and take in your hole system of dizzy, coil and cdi box for testing in unison, which
eliminates any problems in the whole system which is useful. With a performance engine it's also a little less stressful on the motor to be able to
set up the distributor advance on the machine rather than running the engine at 8000 rpm in the car while you wave your timing light around!

Here's Neil working on the advance curve for mine the other night, it's an electronic system from Pertronics so we're checking the phasing between
the twin pick ups as well. At the moment it's showing 13 degrees of advance in the distributor at 8000 rpm which equates to 26 crankshaft degrees,
so by dialing in 4 degrees of advance at idle will achieve the 30 degrees of advance we're aiming for.

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Remember that the distributor is running half the speed of the crank. With the cap on you can test the firing order for example as it might not be
quite as written on the cap itself :roll: also with it running into a spark plug, you can physically check it's sparking through the entire rev range.

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Hope that's of interest.
cheers, Mike.

previously..
1994 968 Club Sport Riviera Blue
1994 993 C2 Carrera Riviera Blue
1972 911S to Martini RSR Prototype Spec
1973 911E to RS Lightweight Specification
1981 924 Carrera GT ex Mexborough car
3.2 Carrera Sport x2
Ferry Man
Nurse, I think I need some assistance
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Re: Distributor Testing

Post by Ferry Man »

Mike wrote:Image
The thing I'm most impressed with is you capturing the spark in that photograph. 8)

Nice write-up. Fascinating stuff. :)
Paul

'74 Porsche 911 Carrera 2.7 (MFI) - Lime Green
'94 Porsche 911 Carrera 2 (993) - Mexico Blue
Mike
Nurse, I think I need some assistance
Posts: 5115
Joined: Wed May 25, 2005 12:39 pm
Location: Hampshire

Re: Distributor Testing

Post by Mike »

Ferry Man wrote:The thing I'm most impressed with is you capturing the spark in that photograph
thanks, didn't have my macro with me, I'll be going for it with that next time :shock:
Beautiful puppy by the way.......
cheers, Mike.

previously..
1994 968 Club Sport Riviera Blue
1994 993 C2 Carrera Riviera Blue
1972 911S to Martini RSR Prototype Spec
1973 911E to RS Lightweight Specification
1981 924 Carrera GT ex Mexborough car
3.2 Carrera Sport x2
mycar
Nurse, I think I need some assistance
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Location: Harrow Gate.
Contact:

Re: Distributor Testing

Post by mycar »

This is excellent news for anybody who has ever wondered about their unknown quantity of a dizzy. (Me)

Will Neil be offering a rebuild/restoration service or is this primarily a diagnostic service ?

Regards, Mike
Mike
Nurse, I think I need some assistance
Posts: 5115
Joined: Wed May 25, 2005 12:39 pm
Location: Hampshire

Re: Distributor Testing

Post by Mike »

mycar wrote:This is excellent news for anybody who has ever wondered about their unknown quantity of a dizzy. (Me)
Will Neil be offering a rebuild/restoration service or is this primarily a diagnostic service ?
Hi Mike, Neil would be only to pleased to test, set up or rebuild anyone's distributor, the machines a really great piece of kit
and that's what he's got it in for. Give him a call on 01296 658422.
cheers, Mike.

previously..
1994 968 Club Sport Riviera Blue
1994 993 C2 Carrera Riviera Blue
1972 911S to Martini RSR Prototype Spec
1973 911E to RS Lightweight Specification
1981 924 Carrera GT ex Mexborough car
3.2 Carrera Sport x2
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