Tach adapter ?

94MR2 · 03-14-2008, 12:11 PM

After going thru every tach adapter thread... Has anyone built the adapter as seen in this link ?
I know there is the popular msd 8920 tach adapter, but if I can fix the problem with $2.00 worth of parts I am up for it.
So from my understanding, the beams ecu outputs a low voltage like 5v or something and the tach wants to read a higher voltage (18v?).

Thanks

puretone · 03-14-2008, 11:15 PM

i thiiiiink somebody on this board did it and bragged about it....

da_horse · 03-15-2008, 08:35 AM

not sure about brag, but the guy who wrote that post for me built me one and its done the job fine so far. i'd open it up again but he sealed it up. does the job so i'm not complaining.
IIRC Roman changed the diode.

Roman · 03-17-2008, 07:41 AM

Hey guys.

Yep, it was me who had it for the grand sum of about $2 worth of bits. :P

However unfortunately for you guys, I have no idea what was involved.

My old man is a bit of an electronics guru, so I gave this problem to him. He came back, after some time playing around with an osciliscope generating a 5v square wave, with a tacho that worked with the beams signal.

I'll ask him next time I see him, how he done it. It was all done on the tacho itself, there was a diode and resistor fitted IIRC, nothing significant.

The most cost effective way to get the tacho signal going is:

1. As per Lander's advice (cheers dude) Use the tacho face from a car with the same rpm scale that fits the MR2 dash (I believe it was a late model carina or corona or something....)

or

2. Use your amazing electronics skills to figure out where the resistor etc has to go.

or

3. Take it to an auto sparky, I'm sure they'd still be able to do it for far less than what a tach adaptor costs!

or

4. Buy a tacho adaptor, if the other options are not feasable!

da_horse · 03-17-2008, 10:22 AM

5. wait for Roman's dad to tell him what he did

puretone · 03-18-2008, 02:33 AM

6. be leet like me and fit your BEAMS cluster to your dash-wiring!

94MR2 · 03-19-2008, 01:50 PM

Quote:

Originally Posted by puretone

6. be leet like me and fit your BEAMS cluster to your dash-wiring!

That would be cool but I dont have either the harness or the cluster

MANDALAY · 03-19-2008, 06:44 PM

You could always buy a new Tacho gauge , approx $200.
But there are cheaper alternatives.

mr220v · 03-20-2008, 04:22 PM

The msd 8950 is reasonably cheap. $45 off of ebay. It also saves me taking my cluster out.

puretone · 03-20-2008, 08:08 PM

Quote:

Originally Posted by mr220v

The msd 8950 is reasonably cheap. $45 off of ebay. It also saves me taking my cluster out.

an RPM activated switch? what for?

94MR2 · 03-21-2008, 10:33 AM

Quote:

Originally Posted by puretone

an RPM activated switch? what for?

He means 8920

94MR2 · 03-21-2008, 11:50 AM

Do you think this unit would work?
OpenDNS

pasqual · 03-21-2008, 12:42 PM

tach adapter SGI-8 D .... easy to install and working
ok

http://www.dakotadigital.com/pdf/sgi-8d.pdf

puretone · 03-22-2008, 02:23 AM

Quote:

Originally Posted by boosted91t

Do you think this unit would work?
OpenDNS

OpenDNS? What's going on here?

puretone · 03-22-2008, 03:41 AM

Hook up an MSD Tach Driver 8913 to our coil on plug's (+) positive wire, and its ground to you guessed it, ground (-) then run the signal wire of your freshly installed 8913 to your MSD Digital Shift Light 8963, proper wires of course, and have yourself is neat little digital RPM display along with shift light!

vvt162 · 03-27-2008, 11:58 AM

Quote:

Originally Posted by boosted91t

After going thru every tach adapter thread... Has anyone built the adapter as seen in this link ?

I just built my tach adapter based on that Toymods link, and it works fine.
I used a Toyota relay coil, a 2N3904 transistor with the 1.2K ohm resistor and 1N4002 diode.

94MR2 · 03-27-2008, 12:39 PM

I just went ahead and bought the msd unit. I tried the toymods link and I couldnt get it to work it wasnt worth my time messing with it. I got it for $60 and it was in my hands in 2 days

03-14-2008, 12:11 PM	#1 (permalink)
94MR2 Beams Owners Group Join Date: Nov 2005 Location: New Oxford, Pa Posts: 389 Thanks: 11 Thanked 7 Times in 7 Posts iTrader Rating: (12/100% )	Tach adapter ? After going thru every tach adapter thread... Has anyone built the adapter as seen in this link ? I know there is the popular msd 8920 tach adapter, but if I can fix the problem with $2.00 worth of parts I am up for it. So from my understanding, the beams ecu outputs a low voltage like 5v or something and the tach wants to read a higher voltage (18v?). Thanks

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03-14-2008, 11:15 PM	#2 (permalink)
puretone Beams Owners Group Join Date: Aug 2006 Location: Aruba, #1 BEAMS Engine on the Island Posts: 2,339 Thanks: 28 Thanked 57 Times in 56 Posts My Google Map iTrader Rating: (1/100% )	i thiiiiink somebody on this board did it and bragged about it....

03-15-2008, 08:35 AM	#3 (permalink)
da_horse Beams Owners Group Join Date: Dec 2006 Location: Victoria, Australia Posts: 162 Thanks: 15 Thanked 23 Times in 20 Posts My Google Map iTrader Rating: (0/0% )	not sure about brag, but the guy who wrote that post for me built me one and its done the job fine so far. i'd open it up again but he sealed it up. does the job so i'm not complaining. IIRC Roman changed the diode.

03-17-2008, 07:41 AM	#4 (permalink)
Roman Beams OCD Support Group Join Date: Feb 2006 Location: Auckland, NZ Posts: 946 Thanks: 23 Thanked 56 Times in 36 Posts My Google Map iTrader Rating: (2/100% )	Hey guys. Yep, it was me who had it for the grand sum of about $2 worth of bits. :P However unfortunately for you guys, I have no idea what was involved. My old man is a bit of an electronics guru, so I gave this problem to him. He came back, after some time playing around with an osciliscope generating a 5v square wave, with a tacho that worked with the beams signal. I'll ask him next time I see him, how he done it. It was all done on the tacho itself, there was a diode and resistor fitted IIRC, nothing significant. The most cost effective way to get the tacho signal going is: 1. As per Lander's advice (cheers dude) Use the tacho face from a car with the same rpm scale that fits the MR2 dash (I believe it was a late model carina or corona or something....) or 2. Use your amazing electronics skills to figure out where the resistor etc has to go. or 3. Take it to an auto sparky, I'm sure they'd still be able to do it for far less than what a tach adaptor costs! or 4. Buy a tacho adaptor, if the other options are not feasable!

03-17-2008, 10:22 AM	#5 (permalink)
da_horse Beams Owners Group Join Date: Dec 2006 Location: Victoria, Australia Posts: 162 Thanks: 15 Thanked 23 Times in 20 Posts My Google Map iTrader Rating: (0/0% )	5. wait for Roman's dad to tell him what he did

03-18-2008, 02:33 AM	#6 (permalink)
puretone Beams Owners Group Join Date: Aug 2006 Location: Aruba, #1 BEAMS Engine on the Island Posts: 2,339 Thanks: 28 Thanked 57 Times in 56 Posts My Google Map iTrader Rating: (1/100% )	6. be leet like me and fit your BEAMS cluster to your dash-wiring!

03-19-2008, 06:44 PM	#8 (permalink)
MANDALAY Beams Owners Group Join Date: Feb 2007 Location: victoria AUSTRALIA Posts: 4,209 Thanks: 136 Thanked 112 Times in 107 Posts My Google Map iTrader Rating: (6/100% )	You could always buy a new Tacho gauge , approx $200. But there are cheaper alternatives.

03-20-2008, 04:22 PM	#9 (permalink)
mr220v Beams Owners Group Join Date: Mar 2006 Posts: 2,529 Thanks: 13 Thanked 176 Times in 147 Posts iTrader Rating: (11/100% )	The msd 8950 is reasonably cheap. $45 off of ebay. It also saves me taking my cluster out.

03-21-2008, 11:50 AM	#12 (permalink)
94MR2 Beams Owners Group Join Date: Nov 2005 Location: New Oxford, Pa Posts: 389 Thanks: 11 Thanked 7 Times in 7 Posts iTrader Rating: (12/100% )	Do you think this unit would work? OpenDNS

03-21-2008, 12:42 PM	#13 (permalink)
pasqual Beams Owners Group Join Date: Apr 2007 Location: BRNO/CZ Posts: 152 Thanks: 5 Thanked 10 Times in 9 Posts iTrader Rating: (2/100% )	tach adapter SGI-8 D .... easy to install and working ok http://www.dakotadigital.com/pdf/sgi-8d.pdf

03-22-2008, 03:41 AM	#15 (permalink)
puretone Beams Owners Group Join Date: Aug 2006 Location: Aruba, #1 BEAMS Engine on the Island Posts: 2,339 Thanks: 28 Thanked 57 Times in 56 Posts My Google Map iTrader Rating: (1/100% )	Hook up an MSD Tach Driver 8913 to our coil on plug's (+) positive wire, and its ground to you guessed it, ground (-) then run the signal wire of your freshly installed 8913 to your MSD Digital Shift Light 8963, proper wires of course, and have yourself is neat little digital RPM display along with shift light!

03-27-2008, 12:39 PM	#17 (permalink)
94MR2 Beams Owners Group Join Date: Nov 2005 Location: New Oxford, Pa Posts: 389 Thanks: 11 Thanked 7 Times in 7 Posts iTrader Rating: (12/100% )	I just went ahead and bought the msd unit. I tried the toymods link and I couldnt get it to work it wasnt worth my time messing with it. I got it for $60 and it was in my hands in 2 days