1968 911S mix too rich at 9.3?

[1968911s]

Had my 1968 S dyno’d today, power was 152.5 torque 127; fuel mix was 9.3 .

Tester suggested mix was too rich, is he right? What adjustments can I make? It’s a stock 911S with K&N filters (in case that matters). Running Esso super which I understand is 0% ethanol 99 octane

It was warm today, so don’t know how much difference that would make vs the ‘book’ power of 160

Thanks Rich

[hot66]

9.3:1 afr?

If so, far too rich. Even MFI motors aren’t running at that level. I can only speak for an MFI system, but for mfi we aim to be late 12’s maybe early 13’s at WOT full load high revs

[Simon Rudge]

Far too rich, agree with James.

Dont be tempted by the pub numbers, engines make what they make, the key in setup is driveability and smoothness. I have done a good few where we could get more horsepower at the top but leaving the mid range a nasty place to be.

The engine will tell you when it is happy, seat of the pants dyno is a good confirmation of where the setup sits.

[Lightweight_911]

.

If they are a competent outfit familiar with 'old' (ie carb-equipped) engines, why didn't you get them to make the necessary adjustments while on the dyno ?

.

[1968911s]

Unfortunately they were not interested in adjusting the carbs.

If I wanted to lean up the 1000-4000 is this an adjustment I can make on the carbs? Without re-jetting ?

[1968911s]

[hot66]

thats not quite as bad as you first made out ... at WOT near the red line your afr isnt too bad