[Tom Vaught]

CENTER CARB 1965 389 engine


The 1965 Pontiac Tri-Power Carburetors information, as requested.
(For verification of the Carburetor Calibrations that you have on your 1965 Engines.
This is the last Center Carb sheet for the 1965 389 Tri-Power Induction Systems

I will post the Center Carb: 7025175 info now. Same format, again, from the Rochester Products People
in the way the information is presented by them. The second of the 1965 Center Carb Calibrations

Air Horn Number: 7017911 (1*)
Venting: Internal 7007199 Vent Tube
External Venting: Idle Vent
Support: None
Needle Seat: 7026336 (2*) Size: .101
Float Valve: 7022783 Pull Clip: 7006474
Float Assembly: 7000273 Spring: None
Fuel Level: .572" at 6.0 psi
Mech. Setting: 1.234" Drop: 1.97"
(to sharp edge of seam at toe of float)
Pump Assem: 7019518 (synthetic)
RET Spring: 7004597 Size: .025"
DUR Spring: 7011385 Size: .045"
Pump Rod: 7013998 Length 2.968"
Pump Jet: drill (2) Size: .026"
Jet Location: In Cluster
CAP cc/10 strokes: 15.0 - 18.0
Rod Set: .880 from air cleaner flange surface to top of pump rod
Power Piston Assy: 7011478 burnished piston
Act Spring 7005841 Oz 8 Color (white)
Power Valve Assy: 7017950
Power Rest: 7010131 Size: (.031)
Metering Rod: (blank) Spring: (blank)
Rod Size, Power (blank) Econ: (blank)
Cut-In down at: 9 "Up" at: 7 hg

MM. Jets: 330 cc, 60 degree, 7008663 "B"
Idle Compensator Assy: none

Choke Housing: 7019587 (3*) bore 1/2
sleeve slot rel. .573 - .577
rest, front .187 rear .089
piston no. 7013888 rest none
Valve No: 7007151 Angle: 20 degrees
cover & coil assembly 7019660
coil 7006894 # 12
activity .388 - .412 rot
torque .1975 - .2225
stat set index (4*)
Fast idle adjust blank
Cam No: 7016086
Choke Link: 7019528 Length: 2.473
wo Kick: .143 - .183 Second Step: .051 .061
Vacuum Break: 23 degrees + - 3 degrees (EMI -19 method "C")

Float Bowl (Finish) Float Bowl and Body Number: 7019928
Venturi Size: 1-1/4"
Cluster: 7019937 Boost Size: 1/8
Nozzle: 7012362 (5*) zero
Idle Tube: 7011033 "C" Size: .033
Channel Rest: 7009246 Size: .044
Hi-Speed Bleed: drill (2) Size: .026
Dome Vent: drill (2) Size: .028
Idle Bleed: None
Top Bleed: .038 over idle tube
Side Bleed: none
Deflector: (2) 7009098
Radial Tubes: (blank) Size: (blank)
Crossover Chan: .125 Main Well Chan: None

Throttle Body Assem: 7029351 (6*)
Body & Bowl Assem: 7029352
Thr Body No: 7029352 Bore: 1-7/16
Thr Valve: 7010178 Angle 11 degrees
Idle Needle: 7013116 angle: 15 degrees
Idle Needle Orifice: .068 - .072
1st Drilling: .029 - .033 (7*)
Spark: none

Port Punch Length: Width:
Port Punch Loc:
Other: 7020783 throttle shaft lever assy
7015148 throttle body gasket
Thr Lever: 7024885
thr shaft offset .017 - .023

Spark Limits blank

Test Specification 7022221
Min Air: .25 lbs min
Idle Air rate: .80 lbs min


Box Balance 18" Hg - 3" Hg
(Note all 2 BBL carbs are tested at 3" of mercury (TV)

Remarks: (1*) 7017442 pump act. Shaft & outside lever assy, 7007506 choke lever & link assy,
7002075 link

7021008 air horn gasket idle vent adj: bend pump lever tang to just open valve
with .020 +/- .005 plug bet thr. Vlv. & bore side opposite idle needle.
(2*) 7006079 needle seat screen
(3*) 7019477 baffle in hsg. .063 dia hole in baffle.
(4*) Choke should just close at 75 degrees F when set on Index.
(5*) 7000291 defusser in nozzle.
(6*) (2) 7017918 .109 dia. Idle channel inserts .153 length pressed in flush +/- .002
(7*) Bottom Slot .057 +/- .004 below top of shaft
Note: 7028797 vac switch assy Adj to obtain 1.088 +/- .010 bet top of bosses on movable lever & top of
switch at W.O.T.

date 6-11-1964 SAE 1-1/4" Spec 2
Customer 1965 2GC Pont. Pow. Pak. "289 Engine" (center) Syn. (They made a typo on the engine size)
7025174 Pow. Pak Assy 7025175 - Center 7025178 - Front 7025179 rear
Model 7025175 Similar to 7024175

This sheet has a lot of changes and is more like the 1st 1965 389 sheet I posted
So the production order would be 2nd sheet, then 1st sheet, and now this sheet.


Tom V.

This completes the 1965 389 Calibration Sheets, I will start on the 1965 421 sheets tomorrow.