Up shift light questions (Page 2/2)
hunter29 MAY 18, 10:41 PM
Someone did the fix before you I presume.
Brian A MAY 19, 12:18 AM
If you want lots of dancing lights related to rpm, buy this sequential shift light module:

https://dauntlessdevices.co...ammable-shift-light/

I have it installed on my Fiero GT track car. You just need tach signal, switched 12v power and ground.

Yeah sure, I shift mostly using my ears but on the track it's easy to get carried away and since the Fiero doesn't have a red line limiter it's nice to have a very visible warning. Plus the lights are a nice visual indicator when a downshift is safe.

I've got it programmed to light a left-most yellow light at 3,000 rpm, light another yellow one at 3,500 and then light a consecutive string of 4 green leds up to 4,500 rpm where torque starts to fall off. I then have two red lights in the sequence warning me that I'm approaching redline and the whole array starts blinking madly in red at redline. There is some latency, so the lighting sequence is conservative.
cartercarbaficionado MAY 19, 12:52 AM

quote
Originally posted by Patrick:

The Fiero's fuel economy shift light might not be "pointless" if your gas gauge is on Empty and there isn't another gas station for 100 miles... but other than that... the flashing shift light is nothing but a nuisance... IMO.


see funny thing is i added one to a ford focus and my 87.
the focus one is much more useful going from yellow for economy to red for the maximum power in the next gear (factory ford cluster but its a stock rally cluster and diesel cluster put together for the looks and extra function)
the 87 i wanted because i think its nice to have.....also that means my idiot lights work since the gauge traces are a little sketchy still

[This message has been edited by cartercarbaficionado (edited 05-19-2025).]

1985 Fiero GT MAY 19, 01:08 AM

quote
Originally posted by Brian A:

Yeah sure, I shift mostly using my ears but on the track it's easy to get carried away and since the Fiero doesn't have a red line limiter it's nice to have a very visible warning. Plus the lights are a nice visual indicator when a downshift is safe.




For the most part they do have red line limiters, I don't know about the 88s, I think they were different but the other v6s do have limiters (a tad above 6000) but you hit it and it will cut fuel until it either hits 4000 rpm or you lift your foot off the gas.
82-T/A [At Work] MAY 19, 06:34 AM
Like Brian A mentioned above, there are a few different devices that allow you to control a shift light. Most of them require some kind of timing box, like an MSD 6EFI (which would be a really nice and simple upgrade on a V6 anyway). You would get multiple spark discharge throughout the RPM which improves drivability, engine performance (mostly at mid to upper rpms) and improved fuel economy.

In any case, you can take the 6EFI's square wave (digital) tach output, and use it to directly control the shift light with a programmable shift light controller. That way, you can kind of use it for something more performance oriented, like... reminding you to shift so you don't blow your motor or something like that.

But to be honest... the only people who really use shift lights are drag racers and track racers... and that's because there's so much damned noise in the car, and so much vibration, that they can hardly see what the RPM is and they need a shift light to literally tell them when to shift. In a normal street car, you're going to hear your motor and feel the car at a much more controlled level... so you're going to be looking at your tach (and / or understand / feel it anyway) so you don't really need a shift light for performance driving.

But I get it... it's cool, and I'd want to use the shift light too if I had one in a car... or even the provision for one.


Here's a diagram I made for a Fiero's 6cyl stock ignition, you'll need this if you decide to wire up a 6EFI MSD box, or anything like that... this is what it looks like stock:

[This message has been edited by 82-T/A [At Work] (edited 05-19-2025).]

css9450 MAY 19, 08:46 AM

quote
Originally posted by Patrick:

No, there's more to it than that. It has to do with engine RPM, manifold air pressure, etc.




That probably explains the shift light that was in my old S-10 5-speed pickup I had for a few years. The light would come on sooner, or sometimes later depending if I was really pushing it, or just lazily getting up to speed. Actually, I mostly just ignored it.

My parents bought a brand-new Honda Civic "1300FE" in 1983 and that car was the one I learned to drive manual on. The "FE" in the model designation meant "Fuel Efficient" and to accomplish that goal, it employed every gas-saving trick in the book. It had the smaller engine and a 5-speed transmission, in an era when the 4-speed was standard. It had no AC, no PS, no carpeting, no radio, no armrests, and a host of other things left off to save weight. It also had a shift light that was programmed to come on REALLY early, apparently to get you into that next gear sooner. My parents would get into big fights arguing about the shift light, because my dad wanted to shift at a higher RPM (you know, so as not to be such a dog in traffic) while my rule-following mother insisted you had to shift as soon as the light came on (thus lugging the engine and I suspect leading to the engine needing valvetrain work by 40K miles). The car was a total slug on the highway with a 0-60 time best measured with a sundial, but I did once calculate a 63 MPG road trip.

fierofool MAY 19, 12:36 PM
I had two identical 85GT's. One had the Up Shift, the other didn't. It activated on the first 3 gears but not on 4th. My 87 GT didn't have the light but my 86 SE does. The light activates all the way to 4th gear but not on 5th,

I converted the 87 to the 7730 DIS system and kept my old ECM. I was having some serious idle issues with the 86 and replacing all of the sensors didn't solve the problem. A PFF member suggested the ECM might be the problem, so I swapped in the 87 ECM. The Up Shift light still works with the 87 ECM.

I've had a few instrument clusters apart but I never noticed if all of them had the Shift graphics on the insert or if some of them were just blanked out. I would expect for cost efficiency, all would be the same whether or not the function was activated on a particular vehicle.

I've noticed that my light isn't controlled by rpm or speed, but by vacuum input. For example, I can cruise at any speed and rpm in 2nd, 3rd, or 4th and the light is on. Accelerate or decelerate and it goes out until it begins to cruise again.

[This message has been edited by fierofool (edited 05-19-2025).]

Kitskaboodle MAY 19, 01:24 PM
Thanks for all the extra input. There’s some good discussion here. Kit