Cliff's Quadrajet Parts and Rebuild Kits

General Category => Quadrajet Carb Talk and Tips => Topic started by: tayto on October 08, 2015, 10:22:17 PM

Title: 17080272 float height and power piston spring
Post by: tayto on October 08, 2015, 10:22:17 PM
Looking for stock float height for 1980 Pontiac Firebird 301 NA (17080272). Research shows 15/32"? cliff sent 4 power piston springs which one is best suited for stock engine? I have original if needed. Lost # of turns of APT from disassembly, what's a good start setting? 3.5 turns from seated? Thanks!
Title: Re: 17080272 float height and power piston spring
Post by: 429bbf on October 09, 2015, 07:47:24 AM
if you have a lot of vacumn , which you should the light blue one would be a good starting point . i use mostly 1/4 in for float height and 3 1/2 is a good starting point for the apt . hth
Title: Re: 17080272 float height and power piston spring
Post by: Cliff Ruggles on October 16, 2015, 05:04:11 AM
The float height is low on many later model stock carburetors because they used high pressure fuel pumps and return lines to keep the fuel moving and cooler.  If everything is stone stock, then use the stock float height.

When the carb is used outside the original application, or with lower fuel pressure, I set those at 9/32".  Never once have had an issue doing this on those later carburetors.......Cliff
Title: Re: 17080272 float height and power piston spring
Post by: tayto on November 01, 2015, 08:28:53 AM
I ended up setting the float at stock 15/32" as far as i know everything is stock. I wouldn't rule out that the fuel pump has been changed at some stage in its life but I would imagine the replacement would be set up similar to original (fuel pressure). Hopefully get it installed in the next week or so.
Title: Re: 17080272 float height and power piston spring
Post by: 429bbf on November 04, 2015, 04:47:04 PM
15/32 mite work on a 301 . but it doesnt work on the gas guzzlers i play with. that is why i set most at 1/4 . my will spit and sputter at high rpms at that height. imo.