hahahaha A few months back I was on a long drive to visit family and this guy in a pickup truck blew by me on I-59. It was about 9pm so I could see the lights of his radar detector on the dash in front of me. He stood on his brakes when I turned on the radar which almost caused his detector to vibrate out of its case! lol I would only give him about a 5 second burst then turn if off and wait for him to speed up again when he thought the coast was clear. We did this dance for about 30 minutes and 10-15cycles of speedup/slow down! hahahaha He finally turned off the interstate at an exit. Its better than listening to the radio! hahahaha Joe
Hi Paul308gtsi has the new style, it is basically a reluctance pickup. This setup produces twice as many pulses as the old style that 11506apollo has. The old style is essentially a 4 pole pulse generator inside. The old style is driven by what was originally used for driving a speedo cable, in fact early 308GT4's had a mechanical speedometer head, probably from a Fiat X1/9! I had thought of this retro step as a useful option on my 308GT4 until I was successful in finding a chip to fix the thing. Both are sealed so cleaning them has no effect. In fact trying to clean the old style with pressure will result in fluid getting into places where it doesn't belong. The board inside is coated but I wouldn't count on it being water proof. Bottom line, if one of your speedos is showing half speed and the other one double then a swap of the heads should result in happiness all round. Only issue then us the odometer records. But the readings there would also be wrong. Gerrit http://dino308gt4.com
Mine is reading fast also.. 5 mph fast at 30 . I just carry my I phone and put it on the dash or garmin.
A couple of years ago I read an artical (popular mechanics I think) where they had developed a small HUD that can be installed in any car. It was based on a small radar unit mounted in the grill of the car pointing down on the road to calculate speed. THe HUD was fairly small which would display the speed up on the windshield. I never heard anything else about it. IT would be neat gizmo to have but I don't recall them discussing price. I think some cars come with factory HUDS now? Joe
Soooooooooo , I does that mean the speedos are fine in both my car 36629 and 11506apollo's car, 38773 ? Do you have any information on why the installation locations are different , 36629's speedo unit goes in from underneath. I'm beginning to think my car has been fooled with by a previous owner . Do both speedo sender units have the same thread diameter , thread pitch and are they interchangable mechanically ? I have been getting an odometer reading of double as well so I am aware of that. All help appreciated , Paul
Oh dear ! I am in trouble now ......... I had a look an older style sender unit one of the UK suppliers has .... and they are definitely not interchangable. I see what you mean about the drive now. I now figure my car has a later gearbox because of the sender. I am guessing 11506apollo's car has the wrong speedo. any ideas out there ???
Let's keep your ideas coming guys, as you are our last resort......! My speedometer is original, and recently calibrated by MoMa in Albuquerque, NM. What you mean I may have the wrong speedo? If it would help, I would be glad to pull the pick-up unit out and photograph it and its threads to show it to you guys..
Hi I don't know the model year of the switch from old to new style sensor. Along with that was the change in transmission housing. If your speedo really is original, including its interior (can't tell from outside) then is your transmission original? I don't have enough parts manuals at hand to check on the switch over year. If you have your sender out, it should say 4 per giri (4 pulses per revolution) or something like that on the outside. If it says something else like 2 or 8, then the sender is wrong. Gerrit
Hey Gerrit, Something is definitely wrong , probably my car has the wrong transmission housing. I have found several odd parts in the back end as I have been fixing things. A wheel bearing housing was painted dark metallic green , one matt black axle , one gloss , yellow paint on bits , , The car is red. So I may have to find a QV speedo to work properly with the sender. I am only taking a guess here but apollo might need to get an earlier speedo. Hey apollo , Can you put up a photo of your speedo , maybe that can be compared to other cars in the 28000 to 38000 range to see if there is any obvious differences between yours and the majority of cars near your chassis number. The speedos did have quite a few different faces over the years. USA cars had a fairly plain speedo that went to 80 or something and that was all for some cars around the early 1980's era , , ,
If im not mistaken I've read a few post on here where the factory's protocal for always using the correct part for that current year was discussed. It may not have been a PO what swapped out "things"? Going from the carbed to the 2v and then to the QV there may have been some mixmatching? Is that correct? Joe
I'm basing my assumption that my car has been fooled with on chassis numbers .......... my car was 1072 prior to apollos and I have a later gearbox / sender. Since there was no real changes between late 80's GTSi's and 82 GTSi's I'm concerned where that later sender / gearbox on my car came from. Maybe it does belong there , , , I'm not sure. It would be nice to know at what chassis number the gearbox / sender progressed to the newer style.
