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mathrich
01-12-2015, 12:24 AM
I made a data logger module that takes a standard automotive tach wire for use with a custom mercury 44 ignition. It uses gps and the engine rpm to create a time log so the data can be graphed and analysed.

I'm curious as to what other drivers are running for tachometers/data loggers. Would anyone be interested in a data logger such as this? It helps to take the guesswork out of changes made to the boat.

Seagull 170
01-12-2015, 06:17 AM
I've used a Velocitek speedpuck, great speedo, big numbers & saves speed & track, but no revs, for about a year, Excellent!

But I'm told there are some new kart loggers that do the same & record revs & sparkplug temps & have warnings on high plug temps.

Let us know what you find.

mathrich
01-12-2015, 12:57 PM
I looked at some of the kart loggers but it seems they base speed on the wheel which doesn't apply on the water. Maybe they have a gps version somewhere.

Aeroliner
01-13-2015, 03:01 PM
You might want to look here! http://www.aimsports.com/

AIM produces a system that uses GPS as the basis for the speed and distance calculation. We have been running the system for 2 years in our MOD hydro's. RPM comes from a mag, ignition plug wire or electronic ignition. The expansion unit also give you acceleration plus other data if you want.They also provide the software to analyze and plot the data for free. It is an outstanding system.

Alan

Cajun Special
01-18-2015, 07:47 PM
I need somthin like this. Just to help dial in my boat for our 6 -600ft drags

Aeroliner
01-19-2015, 02:51 PM
This is their drag version. http://www.aimsports.com/drag/index.html

Hope this helps. Seems like it can easily be adapted to your needs.

Alan

Cajun Special
01-19-2015, 09:11 PM
Awesome thanks

mathrich
01-19-2015, 09:57 PM
I need somthin like this. Just to help dial in my boat for our 6 -600ft drags

What kind of motor do you use? (how many cylinders, 2 or 4 stroke?)

Looks like a cool way of racing, how fast does it take you to go 600ft?

Aeroliner
01-20-2015, 07:37 AM
http://www.boatracingfacts.com/forums/showthread.php?6393-Mercury-Mark-40-H

The above thread that I started some time back goes through what we do and the building of our engines. Our D MOD hydro runs in the low 80's while the E engine runs mid 80's. We run our rings in NBRA sanctioned events where the race course is 3/4 to 1 mile in length. We use the flying start so acceleration is a non event for us.

The engines we run are all Mercury, 30, 40 and 44 cubic inch two cycle. Hydro's run about 12 ft and a complete rig with driver weigh in around 500 pounds. Our first race in NBRA will be in Louisiana the end of April. You might enjoy seeing an event.

This link is from a D MOD race in Mountain Home. https://www.youtube.com/watch?v=6EmyXAFIVZA

Alan