Building up Holley 600 vac sec
Thread Starter
Safety Car
Joined: Jun 2001
Posts: 4,004
Likes: 2
From: Severna Park Md
Building up Holley 600 vac sec
Check my sig and you will see what I have. The Holley 600 on the car now is the same as when it came out of the box. Im thinkin I might be able to get some more performance with this carb if I do the right things. So far I put a lighter secondary spring on it. It improved performance. Should I try and upsize the primary jets? Anyone know what size primary jets first come in the 1850 600? The sparkplugs are clean with no black soot after considerable use. The moter seems hungry. How many sizes should I go above whats already in there? Or should I leave it alone?
Burning Brakes
Joined: Apr 2001
Posts: 752
Likes: 1
From: Springfield Oregon
Re: Building up Holley 600 vac sec (Jvette73)
According to the info in Dec. '01 CHP, the primary jets on the 1850 are 66's, the secondary metering plate is listed as the equivilent of 64's. I have the same carb on my car, with a smaller cam and 75cc heads. Your combo sounds like it could definately use a 3310/750cfm with no sweat. It has 72prim./75sec. jets stock. Also, you could bump the primary,s on your 1850 and convert it for use of a secondary metering block with changeable jets. Hopefully some carb people will chime in with more info. Good luck.
Pro
Joined: May 2001
Posts: 524
Likes: 59
From: watchung N.J.
Re: Building up Holley 600 vac sec (ORVette)
I have a 600cfm and a 10.5 to one 350 engine, and our engine ran best by drilling out the front main jets to .076" and also the metering plater "its made out of alum." to .o78" as well Keep in mind that we reduced the size of the P.V.C. hose by placing a smaller hose in side it, effectivelly reducing it by half, this reduces the air into the carb and will also make the mixture a little more rich. so you should be allright if you have a decent cam and hi flow heads, headers etc. the holes in the metereing plate " alum. part"
are on the very bottom. the lighter spring helped me as well. remember every engine jets diferent so start small and work up, you can find small drills at a well equipted hardware. SPOKE- :flag :cheers:
are on the very bottom. the lighter spring helped me as well. remember every engine jets diferent so start small and work up, you can find small drills at a well equipted hardware. SPOKE- :flag :cheers:
Thread Starter
Safety Car
Joined: Jun 2001
Posts: 4,004
Likes: 2
From: Severna Park Md
Re: Building up Holley 600 vac sec (spokewrench)
Thanks for the suggestions everyone. If you knew me, you would realize how difficult it is for me to leave well enough alone. Im sure I could get more from the smaller 600. I may wind up opting for the bigger carb. :D
