FS-935 Boost Gauge with additional Tell Tale Reset Needle and Key. Replace the Clock.

[jsveb]

Originally Posted by IMR-Merlin

Thanks for this thread, I have the same boost gauge in my project car and now I know how to make a key!

Can you make that two..???

[voitureltd]

When did the factory start to use the christmas tree boost gauge in the 935 cars ( or was that used in later Porsche race cars ) or was that the first boost gauge and the teletale used later?

[NY930]

I have read that the Kremer 935's, originally experimented with the LED boost gauges aka Christmas Tree Gauges, but the team found them not accurate at that time and then used the additional Tell Tale resettable needle boost gauge. It's very functional and allows a driver to concentrate on the road and not be preoccupied with watching the boost gauge so as to not obligate the driver to communicate to the pits the highest boost deviation.

[voitureltd]

In as much as Kremer cars were built later but within the time frame as the factory 935 cars I wonder if the factory started with the LED gauge with the first Turbo cars. It seems more high tech as opposed to the Tell Tale so I just assumed the tell tale was first ( also when was LED developed. I always thought it was more current than in the 70's). As with the Tell Tale there were two manufacturers the 80's. The one that came with a 1983 Kremer is a VDO and the other ( in a 1977 which I had assumed was updated from a tell tale ) is branded Porsche SC which I now think may have come earlier, possibly from the first turbo cars, the 934 time or before. I had previously assumed the LED was later but now wonder as a Porsche SC ( Super Carrera ? ) would be a designation of a early turbo. Anyone have any early photos ( seventies) of any Porsche turbo race car ( turbo race cars were on track before the 934-935 era ), that would show these different gauges in the cars?

[RarlyL8]

My experience with the VDO tattle tail gages is they are junk. The first one I had lasted a year then the TT broke. Replacement didn't last that long. WAY overpriced. I have a fuel pressure gage with tattle tail that I bought from Grainger for $50 that has lasted longer.

[JFairman]

Yeah they are way overpriced, especially now that there is renewed interest in them but thats the way it always is with stuff made for Porsches.

They are made with thin aluminum cases to be light in weight for racing origonally and some of them work perfectly and some don't. There's not much to them on the inside but the brass parts are precision made like an old clock.
Mine is around 7 years old now and works perfect. It was in the car when I bought it.

To test it I've set the telltale needle higher than boost goes and then gone out on the interstate and floored it to see if the telltale holds the boost needle back at all.
The telltale friction clutch is set light enough on mine that it doesn't hold back the boost needle at all and the telltale peak hold stays in place all the time.

A buddy of mine bought a new one with telltale from NHS a few years ago and his telltale has always been too stiff to move freely or something.. even after sending it back once to have the telltale clutch tension adjusted looser.

[voitureltd]

I have 4 VDO teletale gages in 4 cars. One I have owned for 12 years, another 8 years and all were in the cars for many years before i got the cars. Two of them were swapped with the clock when they were just a few years old. Maybe I am lucky but all of mine work just fine. Could be the later ones were not made as well as the early ones were or were kept in a moist or a freezing or high temp climate as that might effect the internals. Always a good idea to get one from or in a well kept car.

[RarlyL8]

Mine were aftermarket VDO made for the masses and not a 935. Paid something like $250 a decade ago for the first one. The TT needles were too tight and held back the boost needle a bit. They broke and just dangle free.

[rdwinelover]

Does anyone have a tattletale key available for trade or sale? Long shot, but thought I would ask.

[bluebox88]

Try Palo Alto Speedometer, they make up reset keys from time to time. Great people for repairs and refurbishing all VDO current and vintage gauges.

Palo Alto Speedometer: Porsche VDO

[ddelano]

Pop quiz... anyone know what the below part(s) are? They are pictures of the adjusting pin / jet in the back of the telltale boost gauges (inside the connection of the pressure line) which is supposed to allow adjustment of the amount of air flow to the gauge to provide enough pressure to move (both) needles but not too much pressure that the gauge is erratic and not smooth operating... I sent my gauge to North Hollywood for repair and they fixed the clutch that was loose but I could still not get the gauge to move (both) needles correctly. I removed my adjusting pin and in the pictures below I think I have identified the problem. The first picture is from Jeff at NHS which clearly (well as clearly as you can get with a cell phone) shows a pin / jet with a hole in the center thus allowing a certain amount of air / pressure to pass through the needle / jet. The subsequent photos are mine which clearly (same comment as above) show a mushroomed / squashed pin with no hole for air to pass. I made an attempt to remove some material and open up the hole with no luck. I included a picture of the screw end that also looks like it has a very small pin hole as well. Jeff tells me he can blow air through his at NHS. I cannot. My questions are; How does this Pin / Jet work? Adjusting it in and outward clearly changes the air volume / pressure the gauge is seeing but how does it do that and if I shorten my pin to open up the hole will that disable the proper functioning of it? Anyone have a good spare they would be willing to part with? I've spent a lot of time and $ on getting the gauge working correctly and feel ever so close... :-) Thanks for the support of this excellent forum.

[gumba]

there's a tattletail key on ebay for $100.00, not mine.

[smurfbus]

I have no problem resetting mine with fingers without the key. This 2bar vdo has been on my car for over 10yrs now (prolly alot longer with POs) and it still works fine. Newer had the key though but there was some glue blob on it before I removed it as it looked tacky. I dont want anything hanging on it as I feel it could put minor stress on it and it could become loose fit after some time.

[porsche 930twin]

Hi all does the reset key wind to reset needle once boost has been reached or do you press the key....

[smurfbus]

You just turn it back where ever you want

[JimmyT]

FS: 935 Boost Gauge Tell-Tale Reset Key, $17.12

[voitureltd]

I'll take four. PM or email me for paypal or another method of payment. Can you put all 4 in the same box priority USPS to reduce shipping expenses? $17,12 X 4 = $68.48 plus $7.90 priority USPS + paypal fees sound right? Thanks,
Tony@Voitureltd

[Capt Bob]

Here is a of photo of my boost gauge...same key but only have (1) key. I had to replace the hose behind the dash as it was dry rotted and cracked causing erroneous boost readings. North Hollywood speedometers tested and calibrated. Works great!

[turbobrat930]

Originally Posted by JimmyT

FS: 935 Boost Gauge Tell-Tale Reset Key, $17.12

I will take two of them. Can you email me? my user name on here @gmailcom

Thanks, Brad

[panzerfaust]

Originally Posted by JimmyT

FS: 935 Boost Gauge Tell-Tale Reset Key, $17.12

i will take one... please PM the payment info?

anyone CAD plating there's? perhaps we can find a somebody doing a batch. its the same cost whether its 1 key or 1000 sort of speak.