The demon carb manual says. The car ran fine before the carb change after the change its idling at about 980 rpmsmy timing is set to 32 degrees total advance.
Comparing The Street Demon With A Traditional Holley Carb
Street demon 625 running rich. Mine is a 625 road demon and it runs rich as well. This can be done by adjusting the carbs performance screws idle mixture screws and float bowl screws and butterfly positions. I just switched from a 4 barrel quadrajet to a street demon 625 cfm carb. Its an 89 302 ho ford racing f cam stock compression ported roller rockers knockoff polished intake ff headers and a older barry grant 625 demon carb that looks all the world like a holley to these aging eyes. Press the screw retainer into position fig. I havent taken mine apart yet but it will happen this spring.
Tuning it is very similar to tuning a holley but its not exactly the same. Everything is running great its just idling to high i read on here that it should be in the neighborhood of about 500 600 rpms. Im almost positive that the pv is too big for my app. If the engine idles smoothly you should not get into any trouble. The primary bores are small in comparison to a standard 4160 holley and it has triple stack boosters. The street demon is a two piece design with all gaskets above the fuel level.
The combination of these things means the street demon has great throttle response and the small primaries also means fuel economy is maximized. Ported stock heads stock comp. Besides a 625 cfm sounds about right for a 350 making 21 hg in idle. I have the same cam as you basically but its a speed pro not a blue racer but the specs you posted are the same as mine mine has a 114 lsa. I just installed a bg demon 625 cfm street demon on 302 mild cam210 212. Unless you live in a state where your car needs to meet tight emissions standards it will not matter if your afr is a bit lean or a bit rich in idle.
All street demon carburetors come with a ford kick down linkage. It runs really really strong only about 4000 miles on the 030 over rebuild. Demon carburetors offer several options to adjust the engines performance. Street demon carburetors will not work with a ford aod transmission. Its on a newly rebuilt stock 283. If the engine runs rough.
There are two important signs which indicate that the carburetor needs to be tuned. Demons are notorious for running rich right ou of the box. Got the four idle mixure screws at abt 34 turns out idles fine comes off idle fine seem too rich they say they are jetted 70 primary and 78 secondary. If running a ford automatic and the kickdown linkage is needed a spring and perch kit part 1954 is required. Remove shipping screw fig.
Gallery of Street Demon 625 Running Rich
