Hi im new to this site so am not sure if the right person will get this message. I am after the specs for a sss datsun in regards to 40mm dellorto carbs. I am after jet sizes, choke tube sizes etc to make my 1200 run mint when I install them. I am a mechanic so technical language will be fine haha. Thanx heaps to anyone who can help.

Is this a New Zealand SSS with A12? And what sort of Dellortos? Are they emissions carbs from an Alfa as you have to run the idles jets richer than normal due to more air through the progression phase (1/4-1/3 throttle).

They are easier to tune for larger engines like L20.

Yes its a New Zealand SSS, believe these carbs are the ones that came off a 1200 but unsure if the get sizes and venturi sizes are correct. Just looking for some sizes that will be a good start point. The motor is running an oval port 1500 head

Ok then should have the correct pregression holes then;

45 Idles,
140 Main,
185 Air Correctors,
30 Chokes.

Thats what i had for a mild 1500cc but with 60 idles to get over the alfa progression issue.

Thanx for that

Hi mate,

I ran it through a program i have, and set it to make peak power at 5500, and it came up with the following.

Choke size: 25
Main jets 100
Air correctors 150
Idle jets 40/7850 (weak .6/.1 rich .8)
Pump jeets 30/35
Max venturis 7848.3

hope that helps

Wow. 25 chokes. Goodluck in finding that size.

@Whitesedan. Can you please explain more about the Alfa dellorto issue. I have a pair of dellortos that came of a alfa.What problems are you referring to with these carbs and a small datsun engine? Thanks.

Perhaps share what's in the carbs you have? I think 1200sss ran 29mm chokes and at a guess the mains are likely to be say 125 or 130.

I seen this guy on Ebay is making custom Chokes for dellorto's. Maybe he can help especially if you need small sizes.

http://cgi.ebay.com.au/dellorto-40-45-48-custom-chokes_W0QQitemZ110125970318QQihZ001QQcategoryZ72469QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

I have some ex-SSS carbs and can't guarantee they haven't been played with but they have 28mm chokes and 120 mains.