Throttle reverse lever under gearbox (bell crank)

[rft218]

Hi All,

I am doing some final adjustments on my throttle linkage to get a smoother action on my 71 s. In trying to follow some instructions in early s register the rod that goes from the bell crank up to the throttle bodies seems too long by about 5mm even at its shortest adjustment.

I am trying to work out why this is - I can just shorten it and thread it a bit more but thinking it through before I do that!!

Looking at the PET there is 2 version of the bell crank:

901 423 027 03 and for later cars (post 71) 911 423 017 01.

From the pictures on line it looks like I have the later one, as the original in NLA from Porsche but appears to be out there in aftermarket.

Does anyone know if these have different arm lengths, which might explain the difference?

Thanks

Roger

[hot66]

I don't know th details of the 901 box cars ..... but looking online does yours have the fixed pin for the throttle pull rod or the one which is held in place with the nut ? .. looking on line there are different throttle pull rods too . Do you have the correct one of those ? ( 69-71 : 901-423-026-03 _

[rft218]

Thanks James, I hadnt spotted that, I will check what I bought from OPC, thats the bit I figured I needed to shorten a bit!

I definitely have the later bellcrank with the separate nut on it that fits the throttle pull rod, I guess as OPC sold me that as a superseded part but the old one is available aftermarket.

[rft218]

...update on this, from James' comments I have checked the parts I bought from OPC and I have the correct throttle rod for 69-71 car, so the question is does anyone know if the reverse levers different lengths for the old one to the newer one?

[SeanP]

There were certainly more than one style of reverse lever. Think it changed on the 915 gearbox. There is also quite a bit of adjustment along the length of the throttle linkage.
Do you have all the bushes in the tunnel?

[rft218]

Thanks Sean, yes have all the bushes in place in the tunnel plus the manual throttle piece. I shortened it about 5mm on the throttle rod and it seems to work well so I will go with that. Hopefully I will see some DDK cars at the weekend and I can compare throttle feel!

[rft218]

For anyone that might read this in the future I have discovered that the bell crank arms are about even on the early one and the output is longer on the later one so it means your pedal travel is too short if you use a later bell crank on an early car. Thanks to Ian 2.2s for letting me sit in and look under his car to work this out!