Holley Jet Sizing [Archive]

bmxerbrett

04-03-2002, 12:30 PM

I have a 1971 buick skylark 350 engine with the ta performance intake on it. Also I have the upper rpm headers by ta. (Compation Headers). I also just got a holley 780cfm model number 4150. I was wondering what jet size I should use?

thanks,

Brett

72skylark

04-04-2002, 08:40 PM

when I had my hollet it was a 600cfm, so my jet size would be different... but I reccomend buying the holley jet assortment... it's like $30 I think... and also buy the spring assortment for the secondary diapragm...

72skylark

04-06-2002, 10:41 AM

Also- the holley jets arent that hard to change, just gets a little messy with gas... how I tunned mine was I went down a long straight road. At various speeds in 1st gear 25 MPH 35 MPH and 45 MPH, holding constant speed, I recorded vacuum reading. I kept changing the jets until I got the highest vacuum readings. thats for the primary jets. A vacuum gauge inside the car is a handy tool, you can get one for $20-$30...
nick