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Holley 4 barrels-What jetting do you run
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Author:  bigtex [ Tue May 13, 2008 8:56 pm ]
Post subject:  Holley 4 barrels-What jetting do you run

I just installed my holley 450cfm/offy. intake on pretty much a stock motor.(I know overkill but once Iam done with engine should be fine).Planning on not "building" the engine until middle of summer so I will be a little over carb'd. for a bit. Iam in the middle of changing my acc. pump cam, power valve and jets. Just trying to get a general idea where to start with jetting..Iam located in San diego (sea level, low humidity and generally 60 to 90 degrees F.) so pretty much ideal conditions.I will be running the "pink" acc. pump cam and not sure but I think the 9.0 power valve. Any and all suggestion appreciated. Thanks

Author:  DusterIdiot [ Tue May 13, 2008 10:14 pm ]
Post subject:  More info...

What car is this going into?

What list number holley (1848?)

If it's a 4150/60 list-1848 450 cfm holley...

I'd do your upgrades (but your pink cam is a bit big for stock)...

I would swap the secondary spring for plain (or brown/black, that will prevent overfeeding the stock engine, and keep the secondaries closed and let you tune for mileage, and tune your primaries).

Try the stock jets first, then read the plugs to see if it's lean (I started with the 57's in my 1848, and had to bump it up to a pair of 60's... but I'm running a bit more than stock)...


-D.Idiot

Author:  the black sheep [ Wed May 14, 2008 1:59 am ]
Post subject:  Edelbrok Setting

HEY ALL

THE BLACK SHEEP here ..

my 500cfm edelbrock is stock in the sec and 7" vac spring with 65/52 metering rods ... and the acc setting is 1 step longer .. due to the fact i run a big pluem 4bbl intake (john cain style ) the motor is mildly modded ,,,

yours in slants

THE BLACK SHEEP ..BAA

Author:  70valiant [ Wed May 14, 2008 3:30 am ]
Post subject: 

I run 57's in mine, 10.5 PV, orange cam and black secondary spring.
I'm far from stock also

Author:  1974duster kev [ Wed May 14, 2008 4:21 am ]
Post subject: 

My motor ran reach for a long time i had to clean plugs once in a while i had a 390cfm holley with stock 51 jets in it and that ran rich i had the headers/intake and carb and it ran rich like that

Kev

Author:  Bren67Cuda904 [ Wed May 14, 2008 5:01 am ]
Post subject: 

390 cfm 4 barrel mech secondaries (NASCAR)
P=56
S=62
PV-P=8.5
PV-S=8.5
P-Nozzle=31
S-Nozzle=25
P+S=White cams
Thottle plates replaced without holes
Floats at bottom of brass plug window.

Ohh - Far from stock too.

Author:  bigtex [ Wed May 14, 2008 7:05 am ]
Post subject: 

Thanks for the starting points. Its a 4160/chokeless/mechanical secondaries Part #9776. The car is a 64 Dart.I have ran the motor but unable to drive it due to I'm still building the throttle linkage. Already my plugs are looking way rich. Thanks agian Jason

Author:  bigtex [ Sun May 18, 2008 8:48 pm ]
Post subject: 

So this weekend I was able to drive the old dart again.I pull a throttle pedal off a mid 70's car and ran the cable off that. I ended up going with the white acc. pump, 6.5 power valve and 59 jets. The car has alot better throttle response and idles smoother. When the secondaries come in its a little too much but I picked up about 300 rpms on my WOT shifts. Very happy cant wait to drive it to work tomarrow :lol: Thanks for everyone input.

Author:  Bren67Cuda904 [ Sun May 18, 2008 9:05 pm ]
Post subject: 

I think your PV is low for a stock engine and your jet is to big.

Author:  DusterIdiot [ Mon May 19, 2008 6:39 am ]
Post subject:  Not really...

Quote:
I think your PV is low for a stock engine and your jet is to big.
The 'stock' PV would have been 8.5 and the stock primaries are 58's... depending on his altitude and his temperature, he is 'close'...(also his secondary metering plate has the equivalent to #70 jets in the secondaries)...

-D.Idiot

Author:  bigtex [ Mon May 19, 2008 7:11 am ]
Post subject: 

I hope to get my new exhaust made soon which will include a single wire o2 sensor so then their will be no guessing. I like to tune carbs. with some sort of air/fuel metering but just dont have one yet.

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