Anyone know who makes this? ( Tramission speedo adapter )
#1
Anyone know who makes this? ( Tramission speedo adapter )
Lo gents, I'm on my way with a Lq4 swap into a ole car.. I'll be using the Turbo-350 that is in the car already but the one issue that i've ran into it feeding a speed sensor into the ECU.
So looking around i found this part:
But i cant seem to find any more information on it,
it plugs into the Transmission or the Cluster and gives a 8 pulse output for an electronic speedo, but also gives a throughput For the wire.
anyone know who makes it? or a part that is similar?
So looking around i found this part:
But i cant seem to find any more information on it,
it plugs into the Transmission or the Cluster and gives a 8 pulse output for an electronic speedo, but also gives a throughput For the wire.
anyone know who makes it? or a part that is similar?
#5
might not be much help, but Dakota Digital dashes used some adapters like that for their elect speedometers
also Street & Performance i think made some adapters
Hall effect or some kind of siginaling, ??????????
also Street & Performance i think made some adapters
Hall effect or some kind of siginaling, ??????????
#7
But I've also read/been told that if you do NOT hook up a VSS, then You *MAY* have idle issues ( to the point of stalling ), as well as reduced power/fuel economy.
so I'm trying to get this cleared up before i finish up the wiring harness that is all apart and on my floor
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#8
Well I can certainly say I have idle issues at times and maybe that is the source of my problem but I need to get with my tuner to confirm it is not something else. With an electronic auto I would think you would need the VSS but not with a 700r4 like I am running. Unless of course that is the source of my idling issues.
#11
I'm assuming it Park / Nuetral swicth and the Tranny convertor clutch swicth. Yes you need a VSS pulse to the PCM / ECM in order for it to take over idle control, when you're stopped. Those pulse generators were used on some F-bodies, when they had computer controlled motors and still had mechanical speedometers. The also used them on the bread style trucks in the mid to late 80's.
#12
I've had a few swaps with TH350, TH400s. you really need a speed signal of some sort.
I had a 383 LT1, Hotcam TH400, even with a 10" stall, coming to a stop it would want to die all the time.
I now have 89 Caprice, 5.3L Drive By Wire, TH400. before the speed sensor, it would idle down to under 400 coming to stop sign, it died 2-3 times in the month I drove it.
What happens, is when you let off the gas from highway speed, and you start to slow down, the PCM thinks it is supposed to idle, no vehicle speed. It see's the RPM higher because you are still slowing down. If you stop too quickly, the engine can die, because the PCM has commanded the idle controller fully closed trying to bring down the idle. If the PCM saw vehicle speed, it would not be trying to close the idle controler. Also with speed signal, during closed throttle decel, the pcm would then go into DFCO. (Decel Fuel Cut Off) DFCO improves fuel economy.
Another Reason. The long term fuel trims, the computers 'learned' fuel correction over time. There are different cells the computer uses to remember what amount of correction was needed in different rpm/load ranges. I don't believe the PCM will use all these cells if it always thinks the vehicle is sitting still.
As for Park/Neutral. I have never run one. Without it, PCM just thinks i'm in DRIVE all the time. I don't seem to see any issues with it. The idle is maintained just fine from Park-Rev or Neutral-Drive transitions.
As for my speed sensor solution on my 89 caprice, I mounted a 15 tooth trigger wheel on the differential yoke. It bolts in place using the 4 bolts that hold the U Joint in. It's cut in half so I can install it without removing drive shaft. www.jagsthatrun.com sell one for 10 bolt chevy rear ends. They also have other speedo pulse generators.
As for the speed pulse for the PCM, I've used down to 4000 pulse per mile, which is about 1.5 pulse per driveshaft revolution. 15 pulse per drive shaft on my caprice is working fine for drive by wire and cruise.
just my experience with this, others may have had different.
I had a 383 LT1, Hotcam TH400, even with a 10" stall, coming to a stop it would want to die all the time.
I now have 89 Caprice, 5.3L Drive By Wire, TH400. before the speed sensor, it would idle down to under 400 coming to stop sign, it died 2-3 times in the month I drove it.
What happens, is when you let off the gas from highway speed, and you start to slow down, the PCM thinks it is supposed to idle, no vehicle speed. It see's the RPM higher because you are still slowing down. If you stop too quickly, the engine can die, because the PCM has commanded the idle controller fully closed trying to bring down the idle. If the PCM saw vehicle speed, it would not be trying to close the idle controler. Also with speed signal, during closed throttle decel, the pcm would then go into DFCO. (Decel Fuel Cut Off) DFCO improves fuel economy.
Another Reason. The long term fuel trims, the computers 'learned' fuel correction over time. There are different cells the computer uses to remember what amount of correction was needed in different rpm/load ranges. I don't believe the PCM will use all these cells if it always thinks the vehicle is sitting still.
As for Park/Neutral. I have never run one. Without it, PCM just thinks i'm in DRIVE all the time. I don't seem to see any issues with it. The idle is maintained just fine from Park-Rev or Neutral-Drive transitions.
As for my speed sensor solution on my 89 caprice, I mounted a 15 tooth trigger wheel on the differential yoke. It bolts in place using the 4 bolts that hold the U Joint in. It's cut in half so I can install it without removing drive shaft. www.jagsthatrun.com sell one for 10 bolt chevy rear ends. They also have other speedo pulse generators.
As for the speed pulse for the PCM, I've used down to 4000 pulse per mile, which is about 1.5 pulse per driveshaft revolution. 15 pulse per drive shaft on my caprice is working fine for drive by wire and cruise.
just my experience with this, others may have had different.
Last edited by busta9876; 12-10-2008 at 12:08 AM.
#13
I'm assuming it Park / Nuetral swicth and the Tranny convertor clutch swicth. Yes you need a VSS pulse to the PCM / ECM in order for it to take over idle control, when you're stopped. Those pulse generators were used on some F-bodies, when they had computer controlled motors and still had mechanical speedometers. The also used them on the bread style trucks in the mid to late 80's.
#14
On some of the GM's they used an optical sensor (my caprice) at the back of the instrument cluster to generate a square wave signal, 4000 or 8000 pulse. problem is the PCM's for LSx's need a SIN wave signal, or alternating current. hall efect, reed switches, will not work, have to be VR or, variable reluctor type.
Yea, I know about them, but felt it was easier to put something on the tranny cable then adapt a dash to fit
#16
Shiftworks modifies the tailhousing so you have both.
sorry forum says exceded uploading quota. See post on similar topic w/ picture.
https://ls1tech.com/forums/conversio...elocation.html
sorry forum says exceded uploading quota. See post on similar topic w/ picture.
https://ls1tech.com/forums/conversio...elocation.html
Last edited by dsrour; 12-10-2008 at 07:03 PM.
#18
I can't completely believe that just a VSS signal would fix my problem. My biggest issue is putting the car in gear and it dying when I first start it. Seems to be so random though. It does it when the engine is hot or cold but never consistantly. I would think the PCM needs some way to know when you put the car in gear. Also, I don't know if this changes anything but I am running a 700r4 tranny.
#19
I can't completely believe that just a VSS signal would fix my problem. My biggest issue is putting the car in gear and it dying when I first start it. Seems to be so random though. It does it when the engine is hot or cold but never consistantly. I would think the PCM needs some way to know when you put the car in gear. Also, I don't know if this changes anything but I am running a 700r4 tranny.
#20
The ones shouwn in the original post, as long as you have enough room to install it. I've installed them on the cruise control box already, when there wasn't enough room in the tranny tunnel. They use to cost around $60 from the dealer, but they were also plentiful in the junkyard, but I don't think they've used them in about 15 or 20 years now. The last one I got from the yard came from a police car with a dash mounted calibrated speedometer in it. A lot of aftermarket gauge packages use them for their electronic speedometers