I have been fooling with Q-jets for quite a few years, and I have this carb I have run on a few vehicles (trucks, cars, Ford and GM big and small displacement) and it has run really good on all of them with nothing but a rebuild about 4 years ago. The number is 17054902. It has pull-over enrichment, and the manual intake choke. The kit, float, and pulloff I used was for '68-'74 Buick 350-455, and I linked the pulloff to the secondary airvalve. I would like to know anything that anyone might know about this carb. I was once told it was an 850 cfm, but I can't imagine it being that big. I need to look down the primaries and see what the ring is. I thought it was a late '70's carb by the number, but I guess its not. It seems to be a replacement carb of some kind. I used Doug Roe's book and Jim Hand's website as a guide and did a little work on the carb though, resized the idle and rejetted (I forget what's in there right now, but it is really versatile) Does anyone else have one of these? It has to be the best carb I have ever had.
Welcome! From what I found it is a 76 Chevy Auto carb. Glad to hear that you like your Q-jet. They are great carbs!!
It has a straight inlet through Thanks for the reply. I am pretty sure it is a replacement Buick carb. I was puzzled about the apparent Chevy relationship, and had some difficult time getting figured out on the kit. There's a 17054900,901, and a 902 that uses the same kit as the 7028244,245, 7029244,245, 7040244,245, 7041245,544, 7042244,245,944, 7043244,245,246, 7044244,245,246,544,546.
It was jetted lean and the passeges needed work And it would make sense that the power piston spring was on the agressive side. I kept it, but I have noticed on heavier stuff it was using more gas than it should. I forget everything I did, but I drilled out the idle restriction in the emulsion circuit and opened up the mixture screw holes. On the secondary side it already had the desireable multiple hole pickup tube configuration, so all I did was ream the little pee holes out at the air horn. I also did a little grinding on the airvalve stop area to get them to open the most they can, they are at 83 right now, the most I can get. I need to change flaps I think because of the kink in them to get to 90 I also roughed up the underside of the flaps but I didn't cut slots in them. I am thinking of maybe getting a set of flaps from a warped 455 Pontiac (heavily smogged APT) carb I've that has the slots cut in. What has deterred me is the secondary pee holes are really big on this carb for some reason and the slots are about twice the size of the Chevy ones. Thanks for your reply carbking. It a relief I haven't worked over a valuable carb. I originally figured it was a heavily smogged carb, but soon found it wasn't.
