LM-2 - Buy Innovate Motorsports 3834 Inductive Clamp ?

taymob · 06-15-2011, 10:51 AM

I just wanted to get some opinions.
I'm thinking about buying the Innovate Motorsports 3834 Inductive Clamp to read RPM's on my 84 carrera. Does anyone have this ? Does it work accurately ? I'm reading mixed reviews. Just don't know if this is a waste of money.

If not how do you get rpm's? Through the tach ? do you have to splice the wires ? What's the easiest way ?

Thanks Tay

DRACO A5OG · DRACO A5OG's Garage

On the LM1, the sensitive and prone part is the WIDE BAND SENSOR ( liken to a O2S ) it is very sensitive to the sniffing of the atmosphere so to get an accurate reading you must insure the sample air is free of unburnt fuel and c/o to obtain a zero reading prior to sticking it into the exhaust pipe.

Sorry I have no experience with the LM2

taymob · 06-15-2011, 11:12 AM

Draco, i think you're taling about the tailpipe clamp. I'm talking about the clamp to read the rpms off of a sparg plug wire.

tobluforu · tobluforu's Garage

Quote:

Originally Posted by taymob

Draco, i think you're taling about the tailpipe clamp. I'm talking about the clamp to read the rpms off of a sparg plug wire.

I have the pickup, but I have an LM1 so I'm not sure if its the same deal as I had to buy an rpm converter as well.

aston@ultrasw.c · aston@ultrasw.c's Garage

I have an older LM1 with the analog interface/rpm box. I spliced into the wire carrying the signal to the tach and connetced it to the interface box. Works great and easy to do.

Looking at the latest Innovate stuff, I think you would need the LM-2 and the LM-2 Analog I/O Cable - P/N: 3811. Based on their description one of the wires in the pigtail is for a tach trigger signal. No need for the plug wire clamp.

taymob · 06-15-2011, 11:58 AM

Tobluforu - Does it work accurately ?

Aston- Yeah the cable will work, but i don't know if i want to splice into my tach wire. I'd rather just clip the plug wire on if it works.

tobluforu · tobluforu's Garage

Mine works great, and I have used it on three cars, but I also have an early car, no ecu, etc..

Tom C. · 06-15-2011, 12:10 PM

Hi . . . I have the LM-2, but no experience with the inductive clamp for RPM input. Instead I just bought the analog i/o cable and took the RPM signal off the distributor signal/trigger wire (factory 2.4 with CDI) or the MSD tach output wire (6AL2) if you got one. And for grins I did use the ground wire to hopefully ensure a cleaner signal. And yes, with the LM-2 it all worked just fine. Nice clean RPM signal with only an intermittent signal loss that you may/may not see in your graphs . . . not a big deal. Hope it all works for you. After my experience with the LM-2 I can't imagine tuning a car without one.

304065 · 06-15-2011, 12:49 PM

Tach signal wire on the back of the tach. Search here for "tachometer compatability chart"

taymob · 06-15-2011, 02:15 PM

Did a search but only found 1 post.

304065 · 06-16-2011, 03:03 AM

Tachometer Compatibility Chart

cmcfaul · cmcfaul's Garage

Tom, can you explain further how you got RPM's from the 2.4 CDI?

diagram would be great

Chris

73 911 E

Tom C. · 06-16-2011, 09:19 AM

On the outside of the distributor is a electrical connection tab where two wires are connected via push-on terminals. . . one is purple/black and the other looks to be solid black. On my car each wire disappears into the wiring harness that extends to the electrical panel. And since this connection at the distributor provides the trigger signal to the CDI, it made sense this could also be used as a good source for the RPM signal to the LM-2. So I found a female-female terminal (1 to 2) that allowed me to add another connection and I connected (via soldered push-on terminal) the RPM (+) wire from the LM-2 analog i/o cable to it. And also attached the RPM (-) wire to an engine ground point. Then after configuring the RPM signal on the LM-2 correctly (can't recall the exact settings) I had a nice clean (semi-reliable) RPM reading.

And I was actually surprised it was this simple because I read about the troubles others have had with the LM-1. But it worked for me. Also it might be worth mentioning that I am still running points in my distributor. Don't know if this matters but for those that have converted to Pertronics/Crane it would be something to consider if my approach does not work for you.

cmcfaul · cmcfaul's Garage

It sounds like you spliced into the same wire used for the Petronics which makes sense. Could a connection also be made on the back of the Tach?

Chris
73 911 e

taymob · 06-17-2011, 06:11 AM

I just went ahead and bought the clamp, i figured for $30 i'd rather just try it.

Tom C. · 06-17-2011, 08:40 AM

Hi Chris . . . yes the input wire to the tach is a common connection point. But with all the talk about noisy RPM signals from the LM-1 users, I decided to take the signal as close to the original source as possible. So I've got an 18ft sensor cable that I run to the tailpipe clamp/o2 sensor and then I run these two RPM signal (+/-) wires along the sensor cable, through the rear quarter window, to the analog i/o cable, onto the passenger's seat so I can monitor/control my LM-2 while road testing/tuning. This setup also allows me to easily swap the LM-2 to another car where my RPM signal source is an MSD 6AL2. It works well for me but I'm sure there is a better solution out there.

cmcfaul · cmcfaul's Garage

Hey Tom, stupid question but where does the RPM signal (from distributor or tach) connect to the LC1? There are two wires with stereo type plug ends. One goes into the laptop. Is the other for the RPM's?

I intended to install mine temporally like you but decided I liked it too much so ran all the wires from the exhaust, over the tyranny and into the tunnel. At the rear tunnel access cover I spliced in additional wires to bring it to the dash where I installed the meter into the cigarette lighter. The two stereo type wires come out of the rear tunnel cover and enable me to connect the laptop while on the passenger seat or in one of the rear seats. Came out really nice and I can simply pull the gauge out and stick it in the glove box.

Chris

73 911 e

Tom C. · 06-17-2011, 11:50 AM

Chris . . . I have zero experience with the LC1. Checkout the Innovate Motorsports Support Forums. They are pretty helpful and you can usually get your questions answered. Or just give Innovate a call. I've always been able to get someone on the phone that has the knowledge to address my question. Sorry I can't provide any real experience on this one.

You might also check out the 'Turbo' forum here (PP). Do a search on 'Innovate' and you will be surprised at the level of useful information on the LC1.

dicklague · dicklague's Garage

If you have not bought the Innovate yet, just get the Wego IV from Pelican. Tach hooks up easily, and you get 2 hours do data logging and soft ware etc.......nice install neat unit and you don't have to keep buying stuff.