I've picked some used Dellorto twin 45's. I've done some research and it looks like i need 38mm chokes, 150 main jets etc

Although i know the carbs came off a 2.0 pinto (same as my engine), i don't know what size the chokes, jets etc are.

a) How do i check the current choke size? Is it simply a case of measuring the Internal Diameter?

b) Would it be a reasonable assumption that if the current chokes are too small, all the other bits (Jets etc) are likely to be too small?

Cheers,
AL

the choke size is stamped on the chokes.

Yep, cheers. They're 36mm.

If i increase to a 38mm choke, do i need to replace the jets, emulsions, air correctors etc with larger ones?

Cheers,
AL

The choke size required very much depends on the cam used, compression ratio and valve timing.

As a rough guide I would assume 36mm is adequate as I use that on a Lancia 2.0l twin cam with 45s .
Puts out around 165 BHP.

I have seen 38mm chokes on 45s but its usualy on a pretty serious engine200hp +

Thats a tall order from a Pinto.

I bought my 45s from a guy who had them on a Pinto, 36mm chokes, he had the engine pretty highly tuned and was getting around 175bhp.

It can cause more problems when you increase the choke size as you reduce the velocity of the air and reduce venturie effect this can reduce performance depending or air flow etc.

If the head is ported and polished and you have a high lift cam, maybe over bore to 2.1l then it may work with biger chokes.

A standard 2.0l may actualy work better with 34mm chokes.


I hope that has made sense

^^^^ wot he said. you are better off going slightly under than over.