Q about Weber jet on hot day ?
 

Since I am kind da new on WEber IDA I hope you guys can give me some advice. For past two event My 13B PP with 48IDA(fuel 155. air 115?) was running very poorly
the engine use to make a lot of power at 6.5K-8k before but now the engine will juse rev to there and I dont feel any power. the car still start fine, and no smoke at WOT so I dont think I damage the engine. I increase fuel presure It doesnt really help. and For this past event the weather was super hot too (100+) will this factor on CARB perforamce too
thanks for your time
j

welcome to the wonderful world of carburetors. there is no temp or atmospheric correction in carbs. therefore you should have a wide array of jets, air correction jets, and emulsion tubes. you will also need to know how each of these influences the tuning of the engine. when the temps change you will need to make adjustments. if you go up or down in elevation changes will need to be made. EGT, AFR, and reading the plugs will give you an idea of what needs to be changed in the carb. have fun and buy some extra needles and seats, as well as gaskets you will need them.

Your fuels seem very small... my 10aPP is running 40 chokes, 180 fuels, 120 airs. With a 13b PP I would have thought you would need bigger fuels than 155's??

Timing is also vital - checked that?

sorry that was my mistake. I always forget what is my main jet size. I run 255 not 155.

I will check my timing and compression when I find a place to do it

I have a lot of experience with tuning a webber and holley in race conditions,
Most important tools, the spark plug you ran and a glass spark plug.
Carfully examine the plug you just ran, is it fowled or white, tune from there, even running premix you can tune for the day's Humidity and temp, or the glass plug, put it in and watch the ignition, to orange or to blue, glass plug is easy and quick, and cost much less than apex seals, which running to lean will cost you. I bought a glass plug a year ago and love it.

Where can I score a glass spark plug?

where do you live? i have a bunch of x-tra jets you could try,,,,,come by the shop

May I know what is " glass spark plug"