kettlman

iTrader: (2)

ok. heres the questions. i know someone knows what are good jet sizes for a holley 650 double to a 12a race-ported engine. please tell. what size to put in primaries and secondaries.

other question? what is the convertion on the jet sizes? like what drill bit would i use to get a 63 jet size? and so on.


thanks

mmasid

I think the number of the jet is the size of the hole in thousandths of an inch. So a 63 jet has a .063 inch diameter hole. I've got a holley 600 on my 12a with 57 primary and a #8 metering plate which I think is equivilant to a 63 jet. I am not happy with this setup and still trying to dial it in.

kettlman

iTrader: (2)

ok. that would make sense. was thinkin .63, but that would be huge. anyways, i hope someone can confirm. i wanna drill my own jets to save money. was told all you need to do is fill the jet with solder and redrill. that way you don't need to spend $7 everytime you wanna try somethin new. and another couple of holes i wanna drill.
thanks.

Sterling

You can buy Holley 10-32 jets at Napa for $32.00 a ten-pack.
Unfortuneately, they are all the same size. Just buy #23s, and drill them to what you want. It's MUCH better than soldering and drilling.
The #s roughly correspond to thousandths.
Here are the Holley jet part #s, Jet #s, and their dilled diameters in thous.


P/N STAMPED
JET # ORIFICE
H302-40 40 .040
H302-41 41 .041
H302-42 42 .042
H302-43 43 .043

H302-44 44 .044
H302-45 45 .045
H302-46 46 .046
H302-47 47 .047
H302-48 48 .048
H302-49 49 .048
H302-50 50 .049
H302-51 51 .050
H302-52 52 .052
H302-53 53 .052
H302-54 54 .053
H302-55 55 .054
H302-56 56 .055
H302-57 57 .056
H302-58 58 .057
H302-59 59 .058
H302-60 60 .060
H302-61 61 .060
H302-62 62 .061
H302-63 63 .062
H302-64 64 .064
H302-65 65 .065
H302-66 66 .066
H302-67 67 .068
H302-68 68 .069
H302-69 69 .070
H302-70 70 .073
P/N STAMPED
JET # ORIFICE
H302-71 71 .076
H302-72 72 .079
H302-73 73 .079
H302-74 74 .081
H302-75 75 .082
H302-76 76 .084
H302-77 77 .086
H302-78 78 .089
H302-79 79 .091
H302-80 80 .093
H302-81 81 .093
H302-82 82 .093
H302-83 83 .094
H302-84 84 .099
H302-85 85 .100
H302-86 86 .101
H302-87 87 .103
H302-88 88 .104
H302-89 89 .104
H302-90 90 .104
H302-91 91 .105
H302-92 92 .105
H302-93 93 .105
H302-94 94 .108
H302-95 95 .118
H302-96 96 .118
H302-97 97 .125
H302-98 98 .125
H302-99 99 .125
H302-100 100 .128

kettlman

iTrader: (2)

awsome. i was hopin you would see and respond to this.

thanks.

Sterling

Actually, you can thank Carl for that one.

Rx7carl

Theres a bunch o charts online that tell you what the #'s correspond to. This fukin banana 0wns j00!!!!!

kettlman

iTrader: (2)

well, what jets should i use for a race ported 12a?

Sterling

That's one for the fruit, Carl...

Rx7carl

What porting?

kettlman

iTrader: (2)

race ported.

kettlman

iTrader: (2)

bump. by the way, where could i get drill bits that small?

Sterling

Burrs, tiny drill bits & other really cool tools (Jewelry Tools)

Sterling

You want item 155-2020 near the bottom; bits #61-80, no metal case. (Unless ya want the case... )