Inliners International Forums General Discussion Engines holley/weber jetting help

Does anyone have a single holley/weber on their 230/250 or 235 that runs well and would like to share their jet sizes? I purchaced a secondhand carb and put it on my '64 biscayne 230 a few weeks ago. I havn't had the idle jet out to see what size it is, but I know I need a larger one, because it wont come close to idleing unless the mixture screw is out 4-5 turns. I have a 145 on the primary side with a 175 (I think) air correction jet. It seems to run ok.. almost as much power as the stock carb, and 2-3 mpg improvement. My main problem is the secondary side. As soon as the secondary starts to open, acceleration stops, and it bogs badly. I've tried a 135, 145, and a jet that I ran a 1/16 drill through (all with a 185 air correction jet), with little or no improvement. It does improve a little when I put the air cleaner back on, which means I'm still too lean, right? Any other suggestions?


Maydaymike
'64 Biscayne 230/pg

The bog or stumble is probably caused from a "accelerator pump"malfuntion. The squirter or it's fuel passage could be stopped up;the pump diaphram bad;the pump linkage improperly adjusted.The idle adjustment screw is controling the amount of fuel delivered at idle- not the air--so make sure the idle speed is correct.The faster it idles the more fuel required so 3-4 turns may not be a problem on some motors. A performance cam may require further mods of the idle circut.Paul

I am running a 261 bored .060 over with stock cam and a holley/weber 32/36 conversion. I have adjust the jets up and down and this is what I ended up with: Idle Jets - 80/75; Main Jets - 140/160; Air Jets - 165/180. with the timing advanced about 5 degrees it runs out pretty good and is getting in the neighborhood of 13-14 mpg at 65-70 mph. Here is a link to a pic of my setup, hope this helps.
http://www.chevygmcofkc.org/Gallery/showgallery.php?cat=500&stype=1&thumb=1&si=261_eng_5

57 Mike

hey mike so let me make sure i'm understanding correctly... you have a 140 on you primary main jet and a 160 on your secondary main jet. Is that correct?

rocketsociety;

I guess that I did not do a very good job of explaining my settings on my Holley/Weber. I'll try again. The primary settings, had a 80 idle jet, a 140 main jet, and a 165 air jet. The secondary side had a 75 idle jet, a 160 main jet, and a 180 air jet. If you are like me you can not leave things well enough alone, so I have been trying some other combinations looking for a little more economy. I am currently running 55 idle/132 main/180 air jets in the primary and 45 idle/140 main/195 air jets in the secondary. Both settings run out fine at hiway speeds of 65-70 mph and seem to provide about the same gas mileage, but I am still not happy with the idle. However, I am starting to suspect that the idle problem is not carb based. I will try and keep everyone updated on what I find.

57 Mike