FAQ |
Members List |
Social Groups |
Calendar |
Search |
Today's Posts |
#21
|
||||
|
||||
Thanks guys for the help. Can one of you send me a picture showing which holes I should open up to .052.
How can I tell if my power valve spring has been trimmed by 5 coils? Thanks for your help |
#22
|
||||
|
||||
Power valve first--Stock spring pressure on the power valve actuating rod is 200-250 grams. With a lumpy cam, that should be lowered to about 180 grams, which normally is about 5 turns of the spring. I measure this with a postal scale graduated in ounces and grams. Just remove the carb top and place the bottom of the power valve rod on the scale and see how many grams it takes to see it begin to retract into the carb top.
Second, I've attached pictures of the venturi assy. The hole located by the #2 in the first photo is where the idle channel restrictors are located. The other photos show various styles of venturi clusters. As Kenth said, stock for a 389 is about .046", with the 421 larger. I would begin with .050-.052". Try a smaller drill first so you can see the angle of the hole so you don't ruin the cluster. I don't know how you'd remove and replace the brass restrictors.
__________________
BONESTOCK GOATS '64 GTO Tripower Hardtop (Wife's Car) '64 GTO Tripower Post Coupe (My Car) '99 Bonneville SE Sedan |
#23
|
||||
|
||||
Mike is pretty much a stand-up guy. Why not check with him on any additional modifications he may have made, and what he might suggest for your current engine configuration.
Mike has bought many sets of the weaker springs from us. You can tell if a spring has been cut by looking at the end. You would not know if Mike reduced the tension on the spring the correct way, by changing the spring. Jon.
__________________
"Good carburetion is fuelish hot air". "The most expensive carburetor is the wrong one given to you by your neighbor". If you truly believe that "one size fits all" try walking a mile in your spouse's shoes! Owner of The Carburetor Shop, LLC (of Missouri). Current caretaker of the remains of Stromberg Caburetor, and custodian of the existing Carter and Kingston carburetor drawings. |
#24
|
||||
|
||||
Can someone post a picture of the idle bypass restrictors.
Thanks, Dave |
#25
|
||||
|
||||
Quote:
Read the post carefully if you want to drill the restrictors. Check for the proper angle with a smaller drill (about .036") so you know how to aim the larger drill. For most replacement cams larger than stock, a good starting point is about .049"-.052". Brass idle tubes about .038-.042".
__________________
BONESTOCK GOATS '64 GTO Tripower Hardtop (Wife's Car) '64 GTO Tripower Post Coupe (My Car) '99 Bonneville SE Sedan |
#26
|
||||
|
||||
Thanks Dick
|
Reply |
Thread Tools | |
Display Modes | |
|
|