Just how adjustable are Non Adjustable Needles?

[mariodschy]

Just thought I would give a bit of an update ........

I managed to get some new pistons and new B1BT needles posted to France all for ?87.50

I think someone must have found some new old pistons as they were not avaialble!

http://www.ebay.co.uk/itm/321648731696? ... xe,ext=ext

or phone Bob at Chatsworth Motor Spares

Just got to fit now ..........AND ADJUST

Any (hopefully good) news for us?

[terryp]

Well, currently still checking and adjusting but first impressions is that the car runs a lot better but that could just be the richer needles.
Plugs are fine and there is no hesitation and it idles better so I am pleased
I will check again with 2 X colourtunes next week

Terry

[mariodschy]

Terry, I presume you are talking about Strombergs. There are generally 3 turns in total then the top bit of the needle unscrews. If set in the centre you can go up 1 ? up and 1 ? down . Everything is however dependant upon the brass jet position that the needle sits in. These, as I recall, are meant to be nominally 100 thou (was told 96) down from the area the jet sits in the carb. As I understand the 1 and a 1/2 up and down allows you to dial in were you need to be. There is not a lot of info' around about this.

This worked for me and I found the jets in the wrong position (60 and 80) and could not achieve what I wanted until they were set right. Also I later saw this in an article in one of the classic car mags confirming the 100thou.

PS it is worth having brand new jets and needles as the side bias wears mark in these (meant to be) very accuarte metering devices. Have a look under a magnifying glass. A groove can also wear into the jet.

Mike

Does 100 thou mean 2,54mm? If yes it's a bit confusing because in the stromberg spreadsheet the distance jet below deck is 0,057" = 1,4478mm, but there is also a "Total offset" mentioned which is calculated from different needle parameters.
@Mike: Where did you have the information about the "100 thou"?

@Terry: Good to hear this great news

[terryp]

Well, currently still checking and adjusting but first impressions is that the car runs a lot better but that could just be the richer needles.
Plugs are fine and there is no hesitation and it idles better so I am pleased
I will check again with 2 X colourtunes next week

Terry

Just to update the car goes like a rocket! Although I won't be getting 42mpg anymore!
I managed to get a pair of new thermal compensators as well for ?10
Took it for a spin last night in the pre summer sunshine and it was great
I believe it now runs as good as Webers or Dellortos
Its only taken me 18 months!

Terry

[collins_dan]

Great to hear, Terry! I'm curious as to how much of a difference you think the thermal compensators have made? Mine have been screwed down tight as I was told they are more trouble than benefit. All the best, Dan

[terryp]

Dan
I think they evened out the idle when hot? Before it was a little irratic.
The B1BT adjustable needles have made the biggest difference. I also overhauled my distributor with one from Kev+2.
The contrast between when I first got the car back together in full federal form with crossover pipes is amazing.

Thanks for your help along the way

Terry

[collins_dan]

Terry, good to know. My idle could be better. It gets lower as it gets warmer, so that may be the cause. thanks, Dan