Weber 48 IDA. Accel pump issue?

Whizbang · 01-08-2014, 08:58 PM

Okay so i have mixed many an issue with this car.

-Timing is correct
-Fuel pressure is around 3.5 psi. (gauge gets jumpy between 3 and 4 but stable higher or lower than that. no idea why). its not the pump
-Jetted per what Racing Beat wants for a 13b 6port stock engine. The carb was running on a 12a streetport for years and ran wonderfully.

The car idles odd when i play with the idle adjustment screws. And for the most part its good with medium speed acceleration enrichment. But quick stabs makes it fall flat on its face. That is with no load mind you.

Car runs great wide open above the 2300 mark.

So it seems like i need more acceleration enrichment. But frankly, i have no idea how to do that.

Could it be the needle valve? Im running a 300 that looks like the the first pic, but i do have some 330s like in the second. I frankly have no idea what the change means or does.

Whizbang · 01-08-2014, 09:31 PM

13B Engine (6-Port)
Venturi - 40mm • Fuel Jet - No. 195
Air Jet - No. 205 • Emulsion tube - F-4
Needle Valve - 300

01-08-2014, 08:58 PM	#1
Whizbang Respecognize! Join Date: Jul 2008 Location: Δx = ħ/2Δp iTrader: (5) Posts: 3,190 Rep Power: 20	Weber 48 IDA. Accel pump issue? Okay so i have mixed many an issue with this car. -Timing is correct -Fuel pressure is around 3.5 psi. (gauge gets jumpy between 3 and 4 but stable higher or lower than that. no idea why). its not the pump -Jetted per what Racing Beat wants for a 13b 6port stock engine. The carb was running on a 12a streetport for years and ran wonderfully. The car idles odd when i play with the idle adjustment screws. And for the most part its good with medium speed acceleration enrichment. But quick stabs makes it fall flat on its face. That is with no load mind you. Car runs great wide open above the 2300 mark. So it seems like i need more acceleration enrichment. But frankly, i have no idea how to do that. Could it be the needle valve? Im running a 300 that looks like the the first pic, but i do have some 330s like in the second. I frankly have no idea what the change means or does. __________________ For current updates and event coverage check out Follow on Twitter! @WhizbangRally Whizbang Rally's Webpage \| Facebook

01-08-2014, 09:31 PM	#2
Whizbang Respecognize! Join Date: Jul 2008 Location: Δx = ħ/2Δp iTrader: (5) Posts: 3,190 Rep Power: 20	13B Engine (6-Port) Venturi - 40mm • Fuel Jet - No. 195 Air Jet - No. 205 • Emulsion tube - F-4 Needle Valve - 300 __________________ For current updates and event coverage check out Follow on Twitter! @WhizbangRally Whizbang Rally's Webpage \| Facebook