Q-jet primary jets/rods size?
05-08-2002, 12:32 PM
#1
Burning Brakes
Thread Starter
Member Since: Aug 1999
Location: Palatine IL
Posts: 774
Likes: 0
Received 0 Likes
on
0 Posts
Q-jet primary jets/rods size?
I've read Lars's Q-Jet Tunning Paper (awesome) and plan on trying different primary jet & rod combinations. I currently have a new Edelbrock Q-jet with primary jets .073 and rods 50m, secondary rods DR.
Questions:
1) What jet/rod combinations have you used on a Vette with similar mods to mine (see signiture)?
2) Where is the best place to by them? Summit Racing sells them individually. Is there any place that sells a kit of different sizes?
Thanks.
Questions:
1) What jet/rod combinations have you used on a Vette with similar mods to mine (see signiture)?
2) Where is the best place to by them? Summit Racing sells them individually. Is there any place that sells a kit of different sizes?
Thanks.
05-08-2002, 02:36 PM
#3
Team Owner
Re: Q-jet primary jets/rods size? (clem zahrobsky)
Nice site Clem! :)
I gather you have the #1903.
Edelbrock sells a "Race calibration kit" that includes several jets, rods, and I dont know what other assorted parts. I think the kit is close to $100. Edelbrock part# 1992. Otherwise I think you have to buy the jets/rods individually (or at least in pairs!). The GM/AC Delco parts can be bought from GMpartscdirect.com or probably ordered from your dealer.
Summit's website recognizes the part number in the format EDL-1992; it's $103.95 !!
Calibration kits for race track tuning
Fits M4M GM Q-jet Rochester, EDL-1903, EDL-1904, EDL-1905, and EDL-1910 carburetors, race calibration kit
This is an assortment of calibration parts for race track tuning including six pairs of primary metering rods, five pairs of main metering jets, five pairs of secondary metering rods, five secondary metering rod hangers, high capacity .149 in. diameter needle and seat assembly, high performance accelerator pump, four power piston springs, and calibration charts.
MJ
[Modified by MNJack, 1:40 PM 5/8/2002]
I gather you have the #1903.
Edelbrock sells a "Race calibration kit" that includes several jets, rods, and I dont know what other assorted parts. I think the kit is close to $100. Edelbrock part# 1992. Otherwise I think you have to buy the jets/rods individually (or at least in pairs!). The GM/AC Delco parts can be bought from GMpartscdirect.com or probably ordered from your dealer.
Summit's website recognizes the part number in the format EDL-1992; it's $103.95 !!
Calibration kits for race track tuning
Fits M4M GM Q-jet Rochester, EDL-1903, EDL-1904, EDL-1905, and EDL-1910 carburetors, race calibration kit
This is an assortment of calibration parts for race track tuning including six pairs of primary metering rods, five pairs of main metering jets, five pairs of secondary metering rods, five secondary metering rod hangers, high capacity .149 in. diameter needle and seat assembly, high performance accelerator pump, four power piston springs, and calibration charts.
MJ
[Modified by MNJack, 1:40 PM 5/8/2002]
05-08-2002, 07:38 PM
#4
Le Mans Master
Re: Q-jet primary jets/rods size? (vettesite)
A good way to start is to use Lars' tuning paper, find an engine that is close and go from there. Remember, the size of the primary jet controls fuel at WOT and the area difference between the jet and rod controls part throttle fuel.
FYI: My '75 ran the following primary jet rod combos:
72/46 stock
74/47 with headers, dual exhaust, Edel 2101 intake and Crane 272 cam (216 @.050). Lars did this setup
75/48 with engine in sig using Lars' info.
My $0.02 is that the Edelbrock jetting is on the lean side.
FYI: My '75 ran the following primary jet rod combos:
72/46 stock
74/47 with headers, dual exhaust, Edel 2101 intake and Crane 272 cam (216 @.050). Lars did this setup
75/48 with engine in sig using Lars' info.
My $0.02 is that the Edelbrock jetting is on the lean side.
