Carb Jetting ?????

DAVID GAGNARD · #1 (**permalink**) 06-08-2003, 06:27 AM

Here's the deal;

Going to open track event at Nashville Superspeedway forth of July weekend. Buddy just bought a new Holley 600 Double Pumper, has not put it on his 67 Fastback yet,still in the box. I'm currently running a Holley 600 Vac. Sec. carb. He told me to take the Double Pumper and use it for the open track event and then return it,no problem....

I'm running a 351-W,approx. 350 hp at the flywheel,iron heads,10.4 to1 compression, Edelbrock dual plane Performer RPM manifold, I do not know what jets Holley sends the carb with (4150 series 4776 carb #),what would you guys recommend for jetting to start with????? Will put in your recommendations and run car and check plugs afterwards and adjust from there,just need a starting point from someone with expereince with this carb...

Thanks;
David

kountzecobra · #2 (**permalink**) 06-08-2003, 06:47 AM

David you're gonna be close at the stock setting which is #66 primary jets. Bolt on and try it. A couple of sizes either direction should get you dialed-in. The 600dp should work great on your car.

DAVID GAGNARD · #3 (**permalink**) 06-08-2003, 09:10 AM

Thanks David, I just looked it up in a Holley book I had and forgot about,according to the book,it should have 66 in the front and either 71 or 76 in the rear...

I'll get it next week and start "testing" it and see what the plugs look like....

David

Roscoe · #4 (**permalink**) 06-09-2003, 08:36 AM

Dave,
The best way to jet down would be to run the engine up to a few thousand and hold it there, under load of course. Shut the engine and yank a plug or two and read it. If it's rich then jet down 2 numbers front and back. Try it again and repeat until it's too lean then go up 2 numbers front and back.

Roscoe