I have recently upgraded the fuel delivery system on the SSS with a Facet electric fuel pump and pressure regulator, bigger fuel line and bigger needle and seats ( from 170 now to 200's ) in the Dellorto 40DHLA sidedraughts. I had been running a standard mechanical pump and factory fuel line.
While it has always had a problem coming out of the tight, left-hand hairpin at Ruapuna spluttering between roughly 5-7500 rpm I have always driven around the issue by short shifting into 3rd and the problem had gone by the time I grabbed 4th gear. This was the only corner between both Ruapuna and Levels Raceway that the car ever played up on.
Now, with the upgraded fuel system the problem is at every left-hand corner and pretty much killing any chance of a decent lap time as I simply cannot get any sort of exit speed out of the corners. I might add that all this was with half a tank of fuel.
The car runs great in a straight line.
I have had my mechanic look at the float levels and adjust them but it has made no difference at all.
I talked to an old school Datsun campaigner ( a very talented driver/ race car builder ) today who was very aware what the problem was but unfortunately was not going to give the info away how to fix it and was too busy ( and 2 hours drive away ) to get him to do the job.
He did mention that some machining of the carbs was required.
Interestingly enough spoke to a chap yesterday with a pretty worked A14 full of goodies from B Pro and Pitt Road ( he is running 45 OER carbs ) who was experiencing exactly the same problem around Ruapuna.
Anyone come across this before and can shed some light on the problem?
Cheers
Dave

I had the same problem awhile back . Was told it was a stuck float and something bout bowls not filling or over filling , maybe float needles . (cant remember exactly ) was a simple fix by carb guy.

Is the fuel pickup point suitable to avoid sucking air on cornering? Also consider placing the fuel reg after the Carbs to ensure the preferred pressure and volume supply. The Fuel Reg ideally should be the last regulation point before return to tank.

Thanks Benny,
The fuel tank pick up has been moved but to an ideal position and also I had half a tank of fuel.
The thinking at this stage is that given the carbs are on an angle which is not ideal every time I go around a left hand corner it is washing fuel over the air jets and effectively flooding the engine.
A lower float level may help but could also create bigger issues.
My Guru is suggesting making an aluminium block to go over the air jets with longer tubes inside them- he was saying this was used some years ago as the problem is reasonably common.
I'll try investigating this theory further but is does make sense and the car definitely does not feel as if it is starving for fuel.
Cheers
Dave

This was a popular remedy to the described problem, back in the day.

Are those tower modifications still available?

Hi Benny,
That's exactly what my Guru described. He also said it was much easier to do on the Webbers than to Dellortos. I don't suppose you would have any pictures of the same sort of mods to Dellortos?
Are they your Webbers?
Cheers
Dave