SpitfireJAGS

I bought a Spitfire Mk4 1300 1974 about a year back, the car is pretty much a restoration project but I managed to drive it all the way from the top of Scotland down to North Wales without any problems the day I bought it. I used it for several weeks and decided I wanted to restore it. I immediately set to work and started to strip the interior out for some welding and repainting of the floor. The car has now been sat for a few months untouched and due to circumstances I need to move it which I thought would be no problem. I tried starting the car up after doing the usual checks and it just didn't want to start at all, on investigation I found that the coil connections had deteriorated and so I bought a new coil and some spark plugs to get her going again. With the new coil and spark plugs she started up, but would splutter and struggle to accelerate. Hunting down possible problems I found that the fuel inside the tank had the usual stale issues, the petrol had gone jelly like and was mixed with water (tasted very acidic, note to self I really need to buy a siphon). I emptied the fuel tank and gave it a thorough clean found it to be rust free (Hooray). New fuel in, pipes blown through, fuel filter changed and carbs cleaned I decided to check the tappets and found them quite far off, so adjusted them with the good ol' Gunson click adjust till they were all perfect. This time she started easily and throttled at idle nicely, on taking her for a test spin carbs started spitting and the throttle was very woolly, just got her back home (Barely) and started again. Cleaned everything through a second time and still had the same issue so decided to treat her to a carburettor service kit from Rimmers. New jets, new needles, gaskets, float needle the lot, fit the carbs back and began tuning, whilst tuning the car seemed to run well but all the problems returned once again as soon as I pulled it out of the garage (perhaps she's scared of the daylight?). Tried rebalancing the carbs and tuning multiple times and receive the same results. There's only about 10 litres of fuel in the tank, I'm reluctant to fill it up more as I have already wasted about 40 litres by leaving it sit although I can clearly see in the tank that it is reaching the suction pipe. I have also noticed a very small amount of bubbles coming through the fuel filter but have checked the fuel lines ect and found no leaks. Has anyone had this experience before or have any suggestions? TIA. Problem: hesitation on load and refuses to rev. Tried: New fuel, new carb service kit, tank cleaning, fuel filters, tappet adjustments, fuel line cleaning, fuel pump gauze filter cleaned. I love my spitfire, I just don't know why it doesn't love me.

Thankyou to all the replies, I've now managed to get my hand on one.

Okay I shall attempt to continue my search for a 1300 air box. If anyone happens to see any for sale please drop me a link.

Does anybody know if the 1500cc air filter housings fit the 1300, I have dual SU carbs, or any other filter housings that fit? I am looking for an original air filter housing to go on my MkIV 1300cc Spitfire and cant find any for sale.