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  #16  
Old 08-10-2017, 09:37 PM
Geoff-R Geoff-R is offline
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Tim, I followed your write up today with some positive results. For the first time I managed to run the car without the choke which is a huge step in the right direction. Whilst I didn’t have hours and hours to work on the car I did manage to do the spark plug gaps, ignition timing etc and then I hit up the carbs. I did hit a few problems in my limited time, I think this is mainly down to the fact that I have round top 240z carbs on my 260, I have no idea what happened to the originals but I’d say the conversion has been done as a bit of a bodge, the throttle interconnection is not the best and I had to really tweak it to open both butterflies at the same time. There must be something missing from mine as there are 2 springs running from the interconnection down towards the manifold, I’ll try and dig a picture out. I think this has a knock on effect as using a syncrometer I can’t really get both carbs below a draw of 11 and then to top it off when I lift the piston in the front carb it doesn’t really have an effect on the idle of the car but the back one does, slight rise and then fall as expected.

Still all that said for a first attempt tuning the carbs I’m quite happy. I didn’t get time to use the colortune I’ll give that a crack next weekend, using that might have given me a better idea of the fuel mix.
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  #17  
Old 10-10-2017, 08:35 PM
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toopy toopy is offline
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Quote:
Originally Posted by Geoff-R View Post
I think this is mainly down to the fact that I have round top 240z carbs on my 260, I have no idea what happened to the originals
This is the preferred set up, the 260z flat top carbs are a pig to keep in tune when old and worn and spare parts are scarce if not unobtanium! 240z carbs are far more reliable


Quote:
Originally Posted by Geoff-R View Post
There must be something missing from mine as there are 2 springs running from the interconnection down towards the manifold
This is correct, these are the throttle return springs
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  #18  
Old 11-10-2017, 01:10 AM
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Jimbo Jimbo is offline
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i hate to say it but the reason you can't balance them and keep them in balance is you might have worn throttle spindles
i had exactly the same setup and had exactly the same problems
however that said you should get a reaction if you open the one front slide???
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  #19  
Old 17-10-2017, 11:38 PM
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TimW TimW is offline
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Hi Geoff, that's good news on positive results. It took me quite a few attempts to get the hang of it.

As Toopy says, 240 carbs are best and the throttle return springs are normal. At first I thought something not right with my springs so tried others, but stuck with the original ones in the end. Post up some pics when you get a chance.

Also as Jimbo mentions, check the throttle shafts using carb cleaner, plus squirt a good load of carb cleaner around the gaskets at the back of the carb where it meets the inlet manifold. I've heard of peeps having them missing. Worth a check I reckon, if only to eliminate
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