Author Topic: ETC limiter advise  (Read 4698 times)

Offline Merryknees

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ETC limiter advise
« on: June 04, 2017, 02:51:39 PM »
Has anyone any experience with using an ETC limiter with a Mallory Mag. Ran the motor up yesterday with low settings to see how it limits the revs. It's reading approx 2000rpm higher than the tach! You can see in the vid the shift light flickering, it was set to 4,200rpm. When I hit the motor the rev limiter kicks in at 3000, it was set at 5000 at the time. Plus the boost gauge went up to 15psi this appears to be due to back fires when the limiter kicks in. Not overly keen on this as you might expect. Any advise would be appreciated.

dreracecar

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Re: ETC limiter advise
« Reply #1 on: June 04, 2017, 04:57:36 PM »
Does it run the same with the RL disconnected?? Try a different tach seperatly for compairison RPM's.  My personal belief is that there is an energy field around the mag that disrupts the signals and tried to get them to work and could not since the manuf spend more effort on battery Ign (sells 1000 to 1) then magneto style in the sportsman classes. I took it off my car, driver said that he could not see it anyway and here in some classes, you are only allowed one high-side RL anyway

Offline 32bantam

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Re: ETC limiter advise
« Reply #2 on: June 05, 2017, 04:56:02 AM »
When I ran the Mallory mag I could not get the tach to read correctly anywhere but at idle. It had a playback and after the run it said over 10,000 rpms! I knew that was wrong!  I tried the MSD mag converter box and when that didn't work I found a tach with the "loop" on the end of the signal wire....that didn't work either. Both set ups the idle was fine.
I have a rpm data recorder on the car and had to put a crank trigger on it just for the rpm recording. That works perfect.
If you don't have a data recorder...maybe the crank trigger could be made to work with the tach you have? 4 magnets on the degree wheel might give enough clean signal to make the tach work?
Anyone try this before???????

I'm running a MSD 20 now......same problem as the Mallory with the "loop" style tach pickuo wire.
« Last Edit: June 05, 2017, 04:57:50 AM by 32bantam »
Steve Walczak

Offline Merryknees

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Re: ETC limiter advise
« Reply #3 on: June 05, 2017, 02:15:45 PM »
All is well with the tach reading,  I have a Joe hunt tach converter supplying the tach signal, same as last season. The problem is the ETC is reading 2000rpm higher than the actual engine rpm!
Now I could live with this by adding 2000rpm to my stage and top end rpm settings on the ETC box.
What really concerns me is the backfiring sound of the engine [flame form the headers] when the ETC limits AND the 15psi intake boost which came up on the gauge when the limiter kicked in. The ETC limiter for the test was set to come in at 5000rpm it kicked in at 3000rpm. So where did the 15psi boost come from?
Really cannot trust this thing so appears a complete waste of money.

Offline Zooman

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Re: ETC limiter advise
« Reply #4 on: June 15, 2017, 04:46:53 PM »
I recently tested an ETC limiter with a Supermag 5 on the bench and found it activated 200 RPM low at 3000 tacho RPM and about 600 RPM low at 7000 tach RPM.

Offline Sidewinder

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Re: ETC limiter advise
« Reply #5 on: July 24, 2017, 04:27:01 PM »
Have had the same problem, ETC kicking in 1500-2000 rpm's to early. The answer i got was to try to shield power leads and also mount suppressed plug cables. I have tried to shielded  cables, ekstra grounding, I don't want to use suppressed cables as i need moore spark from my Don Zig Mag. As for now I use the old set-up with Autometer rev limiter and a eksternal signal converter for the shift-light and tach, and that works perfect. I would love to see a solution as I have already decided to upgrade to a Hunt H3 mag that puts out 3x the amp compare to the old one.
« Last Edit: July 24, 2017, 04:33:32 PM by Sidewinder »