120 liter fuel tank question

[cscrogham]

Anyone who had an optional 120 liter tank delivered in a SWB 911, so what happens with the spare tire?

[Rennman]

I have never heard of a 120 liter tank Cole. Just the 100 Liter tank. The spare would then get a perlon cover and just sit on top of the tank. Brett Johnson's book says there was a tire strap but the 5 factory big tank cars that I have had did not have a strap or holes/provisions for one. Hope this helps.

Don

[Mr9146]

I have never heard of a 120 liter tank Cole. Just the 100 Liter tank. The spare would then get a perlon cover and just sit on top of the tank. Brett Johnson's book says there was a tire strap but the 5 factory big tank cars that I have had did not have a strap or holes/provisions for one. Hope this helps.

Don

Plastic tanks were 110L, no? Same spare situation as above, but we're now talking rally/racing cars which would have had the straps to hold the tire in place.

[gulf908]

Cole,

From one of the UK sites.
I vaguely recollect there were 120 L (race?) tanks in SWB but the 100L (road?) tanks were more common.
The big tanks should be steel in the SWBs AFAIK.
HTH,
Dennis.

[cscrogham]

I was referring to the optional 100 liter tank (not 120 liter, my mistake) that I have seen in a few 67's. I don't see any way to incorporate a spare tire and just wondering if anyone has an old photo, information, etc. The tank is steel and painted black and the space where the tire would be located is now used for more fuel capacity.
I have one of the RS tanks (new) which is grey plastic if you know of anyone that needs it. Another good question is when they showed up, '73 RS only or could you order one in any car? This stuff keeps me up at night. Thanks for the input.
Cole

[cscrogham]

That is very helpful, thanks!
Looks like they just cover the spare by itself and kind of throw it in there...

Cole,

From one of the UK sites.
I vaguely recollect there were 120 L (race?) tanks in SWB but the 100L (road?) tanks were more common.
The big tanks should be steel in the SWBs AFAIK.
HTH,
Dennis.

[cscrogham]

Thanks Don, beginning to make sense to me now. Of all the cars I have owned I don't recall a big tank in anything other than a race car, where the spare wasn't an issue.
It would make sense to have some kind of a spare tire strap though, wouldn't it?

I have never heard of a 120 liter tank Cole. Just the 100 Liter tank. The spare would then get a perlon cover and just sit on top of the tank. Brett Johnson's book says there was a tire strap but the 5 factory big tank cars that I have had did not have a strap or holes/provisions for one. Hope this helps.

Don

[Rennman]

I had a 68S survivor that had the perlon and just throw it in option. See my site under past http://www.Porsport.com it is a Bahama yellow 68S. Johnsons book shows a strap using a luggage strap hold down mounted near the tub number. I remember another 67S streetcar same deal just perlon no strap so I am really confidant that there was no strap.

Don

[edmayo]

Cole, to the best of my knowledge the 85 liter tank was a somewhat popular option for ROW cars, just not DOT allowed here. As to the spare with a 100 liter tank, I just use a couple small tie-down ratchet straps to hold my spare from moving around on my 67. Not fancy, not correct, but does the job!

[a911s]

This is something I wrote with Jeff Smith's help in 2005 for an R Gruppe newsletter. Some of this info may have been superseded:


Porsche provided a variety of enlarged gas tanks for their “sports purposes” factory early 911s and also offered some of them on certain regular production 911 models, depending on year and country. These “big tanks” were installed to provide a greater distance between fuel stops than what was possible at the time with the standard 62L (16.4 gal) early 911 steel tank.

The first big tank to appear for the 911 was the steel 100 liter (26.4 gal) tank painted black on top and listed as option order no. 9499 in October 1966. This same order number appears in the 1967 Porsche brochure entitled “For the Competition Driver”. Interestingly, the factory accessory catalog (publication no. W 12) of November 1967 states: “special fuel tank 100 liter, not for USA". It was a standard option item order for production ROW 911s from ’67 to ’69 and could be ordered from the factory as part number 902.201.010.30. This is also the same part number listed in the 1968 Sport Purposes brochure. During its production period, the 100L tank was made in both center fill and side/fender fill versions. The center fill version was used on the 1967 911R, the 1968 “Monte Carlo” 911T, the 1968 T/R, and some 1970 STs. The 100L steel tank is identical to a stock 62L tank on the bottom. An additional replacement piece is welded over the spare tire area down to the seam in the front and goes up and over on the backside. The 100L tank had its own special longer transmitter (sender), unique gauge, and trunk compartment mat. Because of the 100L tank’s larger size, the full size spare tire sat on top of the tank’s central hump and was tied down (on rally cars at least) at the top left and bottom right by a 356 type hold down and tire strap. There was also a black plastic version of the center fill 100L tank with a metal filler neck and a steel hold down strap. This plastic tank was made by BASF of Lupolen 4261 AX, and was reportedly used in the 1969 Monte Carlo Rally cars, as well as the 1970 East African Safari 911s.

The next big tank was the 110L (29 gal) tank specified in the Sport Purposes brochure with a print date of 3/72, and listed for availability in 1970. The 110L tanks reported are made of grey plastic and have a K. Kurz Hessental KG ***01 70 (1971) stamp number. Some 911ST sports purpose factory 911s, including the 1972 Monte Carlo Rally 911, used the 110L tank, which had a side neck that could be filled through an aperture in the front lid. The 110L tank was also used for the 1973 RSR. I have not seen one listed as an option for standard Porsches meant for the street.

The 85L (18.7 gal) plastic tank is listed in the 1973 parts book and is known as the “RS tank”, since it was standard equipment on the ‘73 Carrera RS. It’s replacement by a standard steel tank may have been an option in certain countries. This tank was also standard equipment on ROW 1973 models of the 911 E and S, but only on those vehicles without A/C and Aux heating as far as I know. It was not available in the USA. The 85L tanks reported appear to have a similar manufacturer and stamp as the 110L tanks but with a different date stamp, ***01 72 (1973). Some of these tanks (perhaps the earliest ones) were colored black but the vast majorities are grey. These RS tanks use the standard sender, but have their own unique mounting tabs and accommodate a space saver spare tire, which was mounted on a 6 inch rim. The one thing to be aware of with the 85L and 110L plastic tanks is that they hang below the undercarriage and may be more prone to damage as a result. Also remember that the steering rack tray is different for the 85L tank - it has a tongue that sticks forward and goes under the tank, this piece being added to the stock tray.