18R-G Carbs

[Night Rider-TA23]

Hey guys, i am thinking of investing in an RA23 with 18rg but no carbs, are there any carbs i could put on that would give it more grunt than the solexes (seeing as how im in the market anyway )

And on that note, has anyone got any for sale


Cheers
Jarrod

[river]

Hi,

You can try some 40mm Webers, 40mm Solex or 44mm Webers or 44mm Solex. Much the sameness amongst them, except the 44mm will deliver more air/fuel than the 40mm, which may make some difference - but not sure how much.

Check the "For Sale" section of the forums to see if any are for sale, also check eBay as sometimes there is some for sale there.

seeyuzz
river

[MWP]

Much the sameness amongst them, except the 44mm will deliver more air/fuel than the 40mm...

But as we all know, bigger isnt always better

The bigger the carb, the more air it can flow at WOT (more power), but the less control (drivability & economy) youll have at part throttle (ie, everyday use).

[ra23celica]

Carby selection is always going to be a balance between power/driveability and availability. Work out what you want, and more importantly, find a good tuner if you are not going to teach yourself how to set them up.

[7t5-27]

I had 44's on my 2tg removed the secondary venturis and rejetted the carbs to match the lack of secondary venturi's the car ran 304/288 cams and would pull strongly to 8500+, The only issue That presented itself with this setup was the car would load up at idle I changed the plugs one heat range hotter and an italian tune up and the car would be fine. I had no drivability issues around town and drove the car daily.
I guess the point is that 44/45's will do fine and will improve the performance the key is to set them up properly decide what the use of the car is, pick the venturi size then jet the carbs to match. (ensuring they are synched and engine is tuned etc)HTH

Greg

[Rodger]

Jarrod,

Come over and see what I have. I'll PM you with my contact details. I'll be home over this weekend.

Regards

Rodger

[Norbie]

I have stock 18R-G carbs + manifold etc I need to get rid of.

There's probably little to be gained with bigger carbs unless you have other mods planned (eg cams).

[Turdinator]

With webers, and i assume the same for solex's, the size of the carb should be chosen based on the choke size you wish to run. Off the top of my head a 40dcoe weber will flow better than a 45dcoe up until you start using chokes of about 34mm. There are graphs of this floating around somewhere. I'll see if i can find them.

What sort of tune is your 18RG in? Stock or modified?

[Turdinator]

Couldn't find the graph yet but here's an interesting formula...

[ra23celica]

I have stock 18R-G carbs + manifold etc I need to get rid of.

There's probably little to be gained with bigger carbs unless you have other mods planned (eg cams).

PM for you thanks Norbie.
Cheers,
Mitch.

[Turdinator]

Finally found the graphs i mentioned above. These are from David Vizard's "Tuning BL's A-Series Engine."



The book does go on to say that when mounted to an engine the differences are usually less obvious as the manifold and head become the restriction not the carby.

[airfireman1]

Just remember that the webers have the choke at the rear of the carb and if you have the newer style short intake manifold with the cast alloy balance tube you will either have to remove the choke mechanism or remove the cast alloy balance tube and blank it off as the choke mechanism interferes with the balance tube and does not allow the carbies to sit flush.That does not happen with solex's as the choke is on the top of them.
Best you do some reading on the 18rg thread.