Rev Counter Problem

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Russtee
Posts: 12
Joined: Wed Mar 12, 2014 3:47 am
Location: Tauranga New Zealand

Rev Counter Problem

Post by Russtee » Thu Mar 20, 2014 8:06 pm

I'm running a Mallory twin point with vac advance, tach reads fine up to 2900rpm and then stops climbing. Anyone know what the problem may be? Have 2 tachs, both do the same

I have Bosch Super inductive spiral wound dist lead, someone suggested the problem is the lead and I should use an older carbon type? Any hints?

And if I go electronic should I use the Mallory trigger or start all over with Pertronix and new coil. I'm running the std ballast resister.
My car runs at 210 on the gauge, is this too much for electronics so close to the engine?

meadowhog
Posts: 391
Joined: Fri Dec 16, 2011 1:50 pm
Location: South Bucks

Post by meadowhog » Sun Apr 27, 2014 1:45 pm

I have exactly the same problem. The issue is the dual points. If you put a piece of card between one set of points you will find it works fine. The answer is electronic ignition.

My rev counter was rebuilt and upgraded to cope with electronic ignition. If your rev counter hasn't been upgraded you may find you have a different problem.

I'm looking at Pertronix but I haven't been able to find out if there is a problem with the III as it sends out three sparks per firing. This may confuse the rev counter so my advice is to go for I or II but that means missing out on the rev limiter built in. However most people over rev the engine when changing down a gear.

Let us know what you do as there seems to be a bit of a gap in the understanding of what works well.

Russtee
Posts: 12
Joined: Wed Mar 12, 2014 3:47 am
Location: Tauranga New Zealand

Post by Russtee » Thu May 01, 2014 9:05 pm

Been reading the net on many experiences of Pertronix etc, seems some have had 20 years of no problems and others not so good.

Back in late 80's we put Mallory coil, wires, and twin point distributor in our race Tiger. The tach would not read past 3000rpm. Tach checked out on a bench test so we phoned Mallory...their tech guy said to throw away their flash dist-coil lead and put the original lead back on...hey presto solved the problem. He said the modern lead interfered with counting of the spark supplied to the dissy.

I wondered if anyone had a similar problem, I can't find an old lead to try the same fix today.

meadowhog
Posts: 391
Joined: Fri Dec 16, 2011 1:50 pm
Location: South Bucks

Post by meadowhog » Fri May 02, 2014 2:22 pm

Surely not the old carbon lead that gave so many problems with mis-fires? Sounds interesting though.

Ive been looking at all sorts of lecky ignitions and they all have the same reports. Some never fail some fail right out the box. Cheapest seems a good bet and buy two so you have a spare!

Russtee
Posts: 12
Joined: Wed Mar 12, 2014 3:47 am
Location: Tauranga New Zealand

Post by Russtee » Fri May 02, 2014 9:08 pm

Yes, exactly the one...you can imagine our surprise when we were told to put the old crusty lead back on, never had a problem in years of racing.

How many Tiger guys have gone electronic? Any used Mallory's module in a series 27 dissy? The Pertronix people tell me my tach probably won't work with their unit without some changes made?

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