To 89mm
Thanks for the comments, & the fact that your A14 Sunny was dyno tuned agrees with what i have said. The Webbers real advantage lies in it's tuneability, but few manage to do it right, & a dyno is the only real way to get it right.

You also mention the fact that it had a Webber. The important part of that sentence is the word "a", which i have taken to mean "one" This too agrees with what i wrote.
Finally you write that it was a 32/36. This means to me that the smallest size of the venturi is 32mm in diameter which also agrees with what i have said.

It sounds to me like you got it absolutely right. Right carb, right number of them, right tuning method,....right on! The fact that you are completely happy with it makes me feel all warm & fuzzy inside.

A carb that is less than the "optimum" size can still be tuned to run real good, but it's best performance will be lower down in the rev range, although something like a lawnmower carb might be going a bit too far.
Chris

What Dodgeman says has a fair bit of merit. The only issue that disagree with (and not too much) is his comments about carb. size.
Provided that the oversize is not way over the top, it is always possible to tune an oversized carb set up. For example, I was using an A14 Sunny Wagon with a 32/36 Weber that had been dyno tuned as the delivery vehicle in our business and it was terrific. There were no flat spots--- the engine opened up cleanly and just pulled its guts out. The worst fuel consumption around the 'burbs was never less than 30mpg and about 36 on a run. The car was never driven less than moderately hard, because A14's like to rev. and they rev better with the bigger carb.
On the other hand, an under carbed engine can never be tuned to any degree of satisfaction.
The moral of all this----If in doubt, think bigger rather than smaller, keeping in mind what you want to achieve

When I last looked, Sticks had a set of GX carbs for sale.
Probably worth looking into----if they've gone, a Weber 32/36 is another really good option.

Thankx again Dodgeman, I will start sniffing round for complete GX setup. If I have more queries i will post again.

Thankx also 1200RC same applies here and if you find out that you do have that manifold available yell out or I could take your offer to borrow for measurements

Thankx again

To 1200RC
There are three main reasons why the Webbers get poor fuel consumption.

1 Because the car they are fitted to gets a flogging everywhere it is driven.

2. Because they are not correctly tuned & the mixture is rich, sending excess fuel down the drain, or the mixture is lean leading to a lot of full throttle operation that ensured that the economiser features are never in operation.

3. A combination of the above.

The GX setup was correctly configured at the factory & provided it is not messed with by that well known mechanic, Dick Fingers [The man with the Cassonova touch. Everything he touches, he ****'s] it will run well & return both acceptable sports performance & economy. A "correctly" set up Webber induction will perform well too, but not many seem to want to spend the money & time at a dyno facility with a Webber expert. Once it is set up right, it would be good.

Back when Chrysler was preparing to use Webbers on the 6 cylinder Chargers, they sent a few engines & cars to the Webber factory with the instructions to set them up right. It cost a motza, but the cars ran perfectly, straight off the showroom floor.

In it's E49 incantation, that 265 cube engine developed 302hp. It is my belief that this was more power per cubic inch than any mass produced passenger car in the world at the time. I like Webbers, but i can not afford to buy them & set them up correctly & the Hitachis provide all that i need at a much more affordable price.
Chris

To Datsterr
When i refered to the L series carbs, i really meant the CARBS alone as a possible substitute for the GX ones. The L series manifold etc. is of course quite diferent.
If you end uo with an incomplete GX induction system, then the SSS carbs may well prove to be a good source of parts, or perhaps to use the complete carbs as replacement ones on the GX manifold.

I believe, but can't say for sure, that the carbs are basicly the same, but i have always assumed, that the SSS ones had a slightly larger throat diameter & if this is so, then they might be better suited to the A14 & A15 engines.

I have two complete L series SSS induction systems. I will use the late model, square top, setup on my 200B & i will have a look at the possibility of using the early round top carbs as a substitute for my original round top 1200GX ones. I wont know till i take the GX ones off & measure them. My little GX will end up at 1434cc, so if the carbs are different, then i have options available to me.

Chris

i manage to get the gx setup recently (18mths ago), they are out there, and as some people dont like the carbies they are generally cheap

i use this setup on my rallycar if you want pictures or anything,

i also have a spare manifold which you could borrow to get dimensions and stuff off, but i already promised it to someone else a while back so id have to check wether he still wants it b4 i could sell it

the main benefit of SU's over weber or dellortoe is a lot less fuel consumption, good for a road car

Thanks again Dodgeman,
I have never had much to do with L series (mechanical side ) but I would assume that the manifold would be different than tha A series .
So using L series Carby option I would need to find new? or second hand twin manifold.
If that proves difficult, as a last resort, would making one be too difficult using dimensions of GX manifold?
When I had dark hair & my chest supported my shoulders not my lungs I played lots with english bikes and old (then) cars so am quite happy with SU (type) carbys
TIA again

Datster
I don't think that you will have overmuch trouble finding a twin carb setup for the SSS L series engines, but i only ever went looking for one set of A series GX carbs [complete assembly] & i found them without trouble, but that was almost 20 years ago, so i have no idea what the situation is now.

There were basicly two types. The early rounded top ones were regarded as "pre polution control" types & the later ones had a bore square shouldered top & these are the "pollution" models. Many do not like these, but there is nothing wrong with them, they just require that you have a full understanding of how they work, & if you follow the manual for tuning them, they will be just fine & it helps to keep the rego Nazi's off your case.

My early 1200GX engine uses the round top carbs, but i have two complete setups for the L series, both early & late & i will be using the late setup on my 200B wagon when i rebuild the engine with Z22 crank, rods & pistons.
This is my parts car. When i need parts, this is the car i go get them in.

I hope that the GX carb supply situation is still good as i'm sure that you will be happy with it once it is correctly set up. The stock GX manifold should fit your A15 head

Chris.
P.S. As far as i can tell, the L series SSS carbs share the same service package [gaskets, small parts etc] as the equivalant GX carbs. This means that you can try Repco & Nissan for bits.

Thankx Dodgeman!
I have trouble asking the search thingy the right questions so don't always get the info I want.
After I posted this I went for a wander through the Treasure Cave of Datsun1200.com and found an excellent article on Carby's written up by ddgonzal.
You don't sound very optimistic me about finding a bolt on setup off a GX, I hope you are wrong.
I am a fair way off needing it as am doing up top to bottom & in to out
Thanks again