DIY-STU thought I was using the 85 mph...I am not, I'm using the 120 mph speedo. So I don't think he was able to help me.

The rotoary switch I am using has 7 positions over 180 degrees or equivalent to a 14 position switch. Not a very common number. In fact, it's extremely difficult, I searched for years until I found one, and it was a Mil-spec, (i.e. expensive) version.

Still haven't built the prototype using the new switch. I would rather find a different A/C panel with different and more common spacing, but I have been searching for years for that too and haven't found it.

Work in progress. Need to be done before 1 may.



Going to use the uper piece from the original doorskin.

quote Originally posted by jscott1: You are going to have to get a Fiero GT cluster from somewhere. One reason why my Plug and play harness costs what it does is that I have to start with a GT cluster just to get the speedometer board out of it. You can try hooking the VSS hi (the yellow wire at pin s) directly to the Firebird speedometer at B12, but it will be an unbuffered sine wave. It may work, it may not, I've never tried it. But most likely it will be jumpy and erratic at slow speeds if it works at all. And if your ECM needs a VSS signal, (which it probably does) you won't have one, and forget about cruise control.

Started to work on the car again and need to fix the speedo. Got a module for it but It will not work soo I will use a fiero cluster and take the part I need. Jscott. Could you tell me how you did. Couldnīt find it here. A lot of pages...

------------------
Regards SHARKMAN
Europe # 1 choptop

here is is... But you have to use an 86-88 GT cluster.



As for the speedometer board (84 non cruise, 85-88):

A - not used
B - not used

C - not used
D - not used
E - not used
F - not used

G - not used
H - not used
J - not used

K - not used
L - not used
M - 4000 pulse per mile buffered VSS (88 only)

N - 4000 pulse per mile buffered VSS (86-87) ?? per Gary W - But not connected on all boards, have to find the signal on the board.
P - black/white - ground
R - puple/white - from the VSS (low)
S - Yellow - from the VSS (high)

T - yellow/black - Ignition power to cluster
U - Dark green/white - 2000 pulse per mile Vehicle speed sensor signal to ECM and Cruise


I hope that helps??

- Jonathan

[This message has been edited by jscott1 (edited 04-09-2008).]

Thanks. I will take parts from the cluster I have in my next projekt car. A GT -87

------------------
Regards SHARKMAN
Europe # 1 choptop

quote Originally posted by jscott1: The rotoary switch I am using has 7 positions over 180 degrees or equivalent to a 14 position switch. Not a very common number. In fact, it's extremely difficult, I searched for years until I found one, and it was a Mil-spec, (i.e. expensive) version. Still haven't built the prototype using the new switch. I would rather find a different A/C panel with different and more common spacing, but I have been searching for years for that too and haven't found it.

I am currently just using a standard dual layer 6 position 30 degree switch. I 'fudged' the switch into position so that the pointer is sort of close to the indications (since 30 degrees is a bit large). Mostly I have the marks lined up, a bit out on the a/c selections, but that is ok since my car does not have a/c and the 'off' (7th position) position does not really matter either.

You can see the pointer is a bit out from the 'floor' icon in this picture (but close enough till I decide the mil spec switch is worth the price):

[This message has been edited by Mickey_Moose (edited 04-09-2008).]

quote Originally posted by Mickey_Moose: I am currently just using a standard dual layer 6 position 30 degree switch. I 'fudged' the switch into position so that the pointer is sort of close to the indications (since 30 degrees is a bit large). Mostly I have the marks lined up, a bit out on the a/c selections, but that is ok since my car does not have a/c and the 'off' (7th position) position does not really matter either. You can see the pointer is a bit out from the 'floor' icon in this picture (but close enough till I decide the mil spec switch is worth the price):

More precisely the Firebird HVAC has 7 intervals over 180 degrees which would be a 25.7 degree interval...so 30 degrees isn't that far off. The Mil-spec switch has 25 degree spacing which is nearly dead on..whether or not it's worth it?? Depends on how particular people are about little things like that.

Greetings from Athens Greece,
Please excuse any mistakes because I have many years to practice my English.

I bought a Pontiac Fiero 86_GT two years ago and the forum was a small treasure of information about how the car works. The fiero is my first car and I didn’t have any experience in cars before. Now I know a lot about cars. I can do many thinks if I have instructions.
Recently bought a Trans am or Firebird 93-96 cluster with metric instruments 240 kmh speedometer. I followed the instructions in the post and I have a small problem with the speedometer, when I am going 100mph the firebird shows 80kmh. The guy I bought the cluster told me that it was from a v6 3.4lt engine.

I use the fiero 86GT speedo board and connect to the 4th pin down from the top ( N ).


Thanks in advance.

Did you mean to say when you are going 100 KPH it shows 80 KPH?

Maybe one of my Canadian or European fiends can help as I have never seen a metric cluster and I'm not sure how they work. But I was told they still use a 4000 pulse per mile speed sensor.

Either way we have two choices... you repace your VSS with a more compatible one or you get a signal converter. The type engine should not matter.

Thanks jscott1 for your reply

When I actually go with 160kmh the firebird cluster shows 80kmh. I have read in other posts that the mph and kmh clusters are the same and only the prints are different.
I have the 4 speed manual transmission, is there any differences with the 5spd VSS?

quote Originally posted by Chris_86GT: Thanks jscott1 for your reply When I actually go with 160kmh the firebird cluster shows 80kmh. I have read in other posts that the mph and kmh clusters are the same and only the prints are different. I have the 4 speed manual transmission, is there any differences with the 5spd VSS?

Okay this is making more sense now... When I read it earlier you threw me off with the mph and kph in the same sentence. You are getting exactly half which means you are getting a 2000 pulse per mile signal off the Pin N. I never have gotten that Pin N to work for me.

I can find a better spot on the board to get the 4000 pulse per mile but I don't remember right now. But don't worry it's an easy fix that doesn't cost anything.

If you have a pic to show me where to find the 4000 pulse it will be very helpful because I don’t have the tools to find it my self.
The speedo board is from an 86GT 120mph.

I was getting a 2000 pulse per mile signal off the Pin ( N ). After some tests following the trace of pin ( N ), I found the 4000ppm on the 86 GT speedo board. It’s the one in the red circle.

quote Originally posted by Chris_86GT: I was getting a 2000 pulse per mile signal off the Pin ( N ). After some tests following the trace of pin ( N ), I found the 4000ppm on the 86 GT speedo board. It’s the one in the red circle.

Yeah I believe that's it. Looks familiar. Sometimes you have to do whatever works. I'll have to bookmark this for future reference.

Got everything to work and will post my notes here for those how need them. I used the SGI 5 for calibration. But I see now that I could have used the point above. I used the N point and got the 2000 pulse. I might change that later and keep the SGI 5 for the next projekt.
Thanks too everyone that given me help In this tread.

Doing some fiber glas work on the door skin know and will have one side ready this week. Have the yearly inspection this week.

------------------
Regards SHARKMAN
Europe # 1 choptop

[This message has been edited by Sharkman (edited 05-07-2008).]

Ye Ole' anti archive bump.

John

JScott 1

Where did you find the mil-spec switch you're talking about and how much is it? I've been looking all over the web and all I can find are custom made switches. I've got to finish this conversion because I've already had at the supports with a sawzall. Thanks in advance.

Sharkman....

How did the glass come out?

dude if you make a kit that lets me put the ta dash and door pannels in i'd buy it...i wouldnt think, i'd just buy it

quote Originally posted by jscott1: My plug and play harness is designed for stock Fieros, using stock motor and ECM. Once you add in an engine swap it might get easier or harder depending on the setup. For most modern engines the ECM probably will have a buffered 4,000 ppm output and no external buffer needed. But you might need to adjust the tach signal.

Saving this from the archives and have a ? on the Fiero speedo circuit board I need to purchase.
I am not running a ECM on the northstar stretch and I believe the VSS on the Porsche trans provides a 4000PPM signal (correct me if I'm wrong on that)
Is it a GT speedo I need or one from a 1988 model?
Then I wire the VSS inputs to pins on that board and use the third one down as an output to the Firebird cluster, correct?

The reason I'm asking is because the speedo is the only guage not working and I recently purchased a 95 Trans Am V8 instrument cluster to correct the tach signal (swapping the V6 cluster to the V8 one since the car has a carbed Northstar V8)
While I'm doing the tach fix, I want to get the speedo working while I'm in there.

Thanks in advance.

------------------

Indy Northstar-Stretch ~ LT1-NOS Roadster

quote Originally posted by Fiero2m8: Saving this from the archives and have a ? on the Fiero speedo circuit board I need to purchase. I am not running a ECM on the northstar stretch and I believe the VSS on the Porsche trans provides a 4000PPM signal (correct me if I'm wrong on that) Is it a GT speedo I need or one from a 1988 model? Then I wire the VSS inputs to pins on that board and use the third one down as an output to the Firebird cluster, correct? The reason I'm asking is because the speedo is the only guage not working and I recently purchased a 95 Trans Am V8 instrument cluster to correct the tach signal (swapping the V6 cluster to the V8 one since the car has a carbed Northstar V8) While I'm doing the tach fix, I want to get the speedo working while I'm in there. Thanks in advance.

Don't know what the Porsche transaxle outputs...but assuming it's an analog 4000 ppm similar to a stock Fiero transmission, the speed buffer you seek is from either an 88 or an 86 to 88 GT speedometer. Several of the posts above show where to get the proper signal depending on which board you actually used.

By the way, you can adjust the tach on the V6 Cluster just by altering the value of a particular resistor. Micky_Moose showed me how to do it, and I believe the instructions are earlier in this thread.

Thanks Jonathan!
Tried to give you a plus rating but alas I had already previously for "Tach help" (go figure)
If anyone has an extra speedo as described above available, please send me a PM.

Ryan

[This message has been edited by Fiero2m8 (edited 11-10-2008).]

quote Originally posted by jscott1: As for the speedometer board (84 non cruise, 85-88): M - 4000 pulse per mile buffered VSS (88 only) - Jonathan

Do all 88's have an M pin that works or does it matter if it's 85 vs. 120mph.
(Forgive the question if all 88's are 120mph...)

The 1988s coupes did come with the 85 mph speedos, but they DO have the M pin unlike the 84 to 87 versions of the 85 mph speedos.

Thanks again jscott1

Jonathan:

Are you still selling the Fiero - Firebird harness adaptors?

Thanks in advance.

John

quote Originally posted by 1986GTV8: Jonathan: Are you still selling the Fiero - Firebird harness adaptors? Thanks in advance. John

Yes, The only issue I have which is unresolved...is that the Firebird Tach doesn't like to play well with HEI distributors. Mickey_Moose has built a filter that worked for him, but I haven't gotten mine to work yet. Still playing with it, and expect to have a solution soon.

Been a while.

Any progress on the HEI ?

quote Originally posted by 1986GTV8: Been a while. Any progress on the HEI ?

Sort of... Tim, (Mickey_Moose) was nice enough to rip apart his dash and get some documentation on his HEI filter. I've built two of them and neither worked. I'm working on a third one and maybe the third time will be the charm. But I have to rip apart my dash to test it and I haven't had the time to do that lately.

quote Originally posted by jscott1: I've built two of them and neither worked. I'm working on a third one and maybe the third time will be the charm. But I have to rip apart my dash to test it and I haven't had the time to do that lately.

Just to update this thread the third HEI filter was a complete success. Just finally got around to putting my car back together from the test. There must be at least two variations on the tach board and I think only one of them works as an HEI filter. Or at least I'm not 100% sure why the first 2 didn't work, but now I do know what does work.

I need to build a harness for myself. Out of all the ones I built so far none has been for me.

I have a question about speedos since you gentleman appear to have more than just your homework.

I own two '84's. The head gasket in #1 blew so I swapped in the engine from #2. I swapped only the engine as both were 4-spds with similar options. #2 had A/C but I didn't figure that'd be an issue.

About 3 months after the swap, my speedo started acting funny... jumping erratically from the displayed speed to zero and back at very random intervals and not very often. It slowly got worse and worse until the speedo would no longer register my speed, but would just jump all over the place, even going all the way around at times. I'd had all I could stand so I swapped in the speedo from my #2 Fiero. Problem fixed...or so I thought.

Initially, the speedo would register 15 m.p.h., car running sitting still. Once I got out of the driveway it seemed to all of the sudden wake up and remember it was a speedo and would display the correct speed. It slowly worsened until now it not only refuses to display the correct speed, it displays 15 m.p.h. until I get to highway speeds when it suddenly climbs to 76 m.p.h. and stays there until I hit an off-ramp and decelerate from highway speeds. (I can't be certain of the speed this happens at as I am decelerating.)

I have changed the speedo. I have not changed what I think is the VSS. If I'm right, the VSS is the only electrical doo-hickey on the '84 4-speed so changing it doesn't appear to be involve any sort of hurculean effort.

My question is, does my issue appear to lay in the VSS or does it seem to be within the confines of my speedo? Either way is fine with me as I've had my speedo apart before and even altered the mileage on my Nissan swap to 000000.0, lol. (just for schlitz and giggles.) How can I fix my speedo? Any help you guys can offer is appreciated more than you know as I'm tired of having to remember how fast I'm going by looking at the tach. (Although, I have become very knowledgeable of the rpms needed to maintain a given speed in at least three different gears, hehe.)

Without being able to do any troubleshooting, I would guess that your second speedometer is also going bad. The VSS doesn't usually fail in the way you describe. They are more of an all or nothing kind of thing.

These electronics are over 25 years old and the problem with using spare parts is that they are just as old and prone to fail. I replaced the ECM on my Indy and it lasted a week before it too let the smoke out. I went ahead and replaced it again and the replacement is holding years later. I know it seems suspicious to replace a part again, but I think that another speedometer would correct your problem.

If you don't have cruise then you can use any Fiero speedometer. If you have factory cruise then you need to stick to the 84 Fiero speedometer.

Thanks for the info JScott, I really appreciate it. Now, you said I could use any Fiero speedo...does that include the 120 m.p.h. speedo? I understand that the only way this car will ever see more than 85 m.p.h. will be if I drive it off a cliff, but if I can find a 120 speedo, the cool factor goes up by 1° - 2°. I don't know if both speedos operate off of the same 4000ppm I read about earlier and I'm not altogether certain I'd understand it all unless I read it about four or five more times.

[This message has been edited by Brocephus (edited 05-31-2009).]

quote Originally posted by Brocephus: Now, you said I could use any Fiero speedo...does that include the 120 m.p.h. speedo?

Yes, you can use the 120 mph speedometer. There are a few sublte differences, but it's mostly plug and play. The 84 has a separate door and decklid ajar light and you would lose that. Also, if you add a cluster with an oil pressure gauge you need to add the gauge sender versus just the light switch. But other than that it's pretty easy.

Well, after another trip to Gordo and Red's place, I have a new left side ashtray cover (to replace the one I broke trying to reinstall after cleaning), a working speedometer, a clean engine bay, a full belly, and the wonderful aroma on my clothes that only a bonfire can produce.

(And Red, I need to make sure Christy gets the recipe for your homemade macaroni. mmm-MM!)
Thanks again!

will have to check out your car one of these days at any of the texas shows.

quote Originally posted by Haggerty: will have to check out your car one of these days at any of the texas shows.

If you mean my car...the last time I had a Fiero out and about was at San Antonio in May; although I rode it hard and put it up wet and that was the end of that. Time to take them out of summer hibernation and get ready for the fun in the fall.

quote Originally posted by jscott1:

Hey you caught wife and me hugging in the background...LOL and ass end of my car...great picture!!!

Anti archive bump

jscott1,

(for starters i'm a buddy of OH10fiero and i'm currently using his login at work); also i do not own a fiero at the moment. i'm attempting to 'retrofit' my 87 Iroc with a 01 camaro ss gauge cluster. i've noticed that you were doing the conversion to your fiero and figured i'd ask you some questions. as a bit of background; it's a 87 Iroc camaro with the 305 tpi v8 and had the mech. speedometer. i was thinking (and here lies the question) would i be able to run a 8k signal generator to a 'dakota digital' speedometer signal interface, the signal interface would step down the ppm to 4k ppm and 2k ppm. the 4k would run to the 01 cluster and the 2k would 'emulate' the vss and supply the computer with the much needed 2k ppm input. i understand that the odometer would be incorrect for my camaro and that half of the 'dummy lights' on the 01 cluster would not apply, however that is perfectly fine my me. i could always find a gauge shop to 'calibrate' the odometer. moreover, my question is, do you believe that this setup would work? thanks.