Hi all, sorry for wasting a thread line, just need some urgent/quick advice on this.. You guys say the Rochester is the best carb for the Buick 350 and Rochester carbs are like impossible to find over here, this one just came up.. is this the one? I do have a 4bbl intake on my 350. thanks a million! and sorry for wasting a thread just for this...
Yes, if you are using the stock intake that is the one you need to use. You can add a 1 inch 4 hole spacer to those to get a little more action from the intake, a little more velocity. If you run the TA intake you can use just about any carb you want just have to tune it. But I do know the Holley 4 bbl double pump is 30 more horse than the Carter AFB 750. Not sure on the Q-Jet never ran one, have one on my stock 4 door Skylark with a 350 and i will leave it that way.
Looks like a side inlet Chevrolet late 70's unit is my guess. Don't expect it to run right on your 69 350 without at least some re calibration/re jetting. It can be made to work though. Buick Q-jets have a front facing fuel inlet. If you can pick it up cheap, get it. Be nice to know the part number. Should start with 1705----
I'm not running anything out of stock other than the cam (there's a build thread on my engine), on another previous thread all the guys mentioned the Rochester was the best, as I have a Holley carb, but Rochester are hard to come by over here and the last one that turned up wasn't the right one I can ask the part number.... the guy only wants £40 for it. He does say it was on a chevy though.. yes recalibration and jetting..and a good clean. the engine was running good with the Holley it has, but seeing as you guys the Rochester is much better for the Buick, then if this one is good I'll get it to eventually swap with the Holley, just a good opportunity at £40... and being a side inlet chevy will it still be good? or better hold for a Buick one if ever turns up?
Yes, you can make the side inlet work. It's easy to make another fuel line. Grab it. Get this book, https://cliffshighperformance.com/Q...ld-and-modify-rochester-quadrajet-carburetors
Make a braided line. https://quadrajetparts.com/adapter-inlet-fitting-p-366.html https://www.summitracing.com/parts/sum-220687b/overview/ https://quadrajetparts.com/fuel-inlet-adapter-fitting-p-369.html There are a number of ways to make it work.
Thanks Larry, I'll get it then, for £40 is worth a shot! if the only difference is the inlet then it's an easy modification.
Yeah, if you read that book, you can modify that carburetor to be just as good as any other Q-jet for your application.
On the other hand, someone could seemingly ship the correct one over to you - Either rebuildable or after being sent to one of the QJ guys for a rebuild. Guy local to me has one for a '70 350 (7040244) he's been trying to sell forever for $125, but I'd bet a wanted ad on here would yield one for even less.
The problem with shipping is the price.... if you consider the weight of a carb and think that TA wanted 55 dollars just to ship an oil pick up for me, imagine how much a carb would be! the engine ran ok with the holley I have, but after reading it would be better with the Rochester, and seeing as I have the chance of this one for £40, I might as well grab it, try rebuild the best possible...and who knows might not run as perfect as one of those built by those clever people, but might run better than the holley? well.. that's what I'm thinking anyway.
I would just run the Holley. Put the cash into an air/fuel gauge to dial in that Holley and it'll run as good as some random old Q-Jet that needs a rebuild and all kinds of re-calibrations that may have worn out throttle shafts/throttle shaft bores. Holley carbs are WAY easier to re-jet and WAY more tune friendly IMO than the Q-jet. Plus they just look WAY better as well. Dealers choice.
Your Buick will PERFORM better with a Quadrajet DEPENDING on what type of Holley 4 barrel you have. IF you have a VACUUM SECONDARY Holley, then YES the Q-Jet WILL flat BLOW AWAY the Holley vacuum secondary as far as performance IF you have a Holley DOUBLE PUMPER, then the performance between that and a Q-Jet will be near the same on a dual plane intake like the stock one or the TA Stage 1 intake.
I wouldn't bother getting a qjet that wasn't intended for a Buick 350 from the factory. that's a chevy style carb. The qjets I like on my 350s are 17058241. 800cfm M4MC carbs from 1978. 1705 carbs are the ones with the choke housing mounted on the side, the M4MC model, the 8 (or 6,7 or 9) indicates the year, 76, 77, 78, 79, etc, 2 is for 4 barrel non california emissions qjet, 4 is for the division, 4 means Buick, and the last number can be whatever. Odd normally means it was destined for an auto car, even usually means manual, but they have very little correlation to eachother. Of course, your holley (from the looks of the valves) was running pretty good, so I wouldn't mess with it. Especially considering you're 1000s of miles away from where all the qjets are lol.
ok, so I'll give it a miss on this Rochester. I might ask my friend who has the Apollo parked up for the last 12 years if I can have a look at what carb he has on it and maybe "borrow" it. or even later in the year try to find a Rochester over there in the US and ship it in the container like all my parts came over. I think there's a container coming end of April (but no money to spare on it at the moment) and another end of the year. thanks all, appreciate all your advice as always.
Hey do what Larry said and buy the carb and get the book and other related parts, this thing will run fine. The darn engine is not going to know you have a Chevy Q-Jet on it. Recalibrate it for the Buick 350 engine and you be fine. For 40 pound it is worth it. I will tell you this, A Square bore Holley WILL NOT WORK on a stock intake with that open spacer you have to use to make it work. If you have the TA intake it won't matter which carb you use. If you want to make things better for tuning get a O2 sensor and put it in the header or just past the exhaust manifold on the stock pipe afterwards and tune the carb with that. Or take the darn thing to the track with jets in hand and go by MPH on tuning the carb. If you can get a Buick carb great, but if you can't get it yet use the Chevy Q-Jet you will be fine.
Get the number off carb . Contact Mark at Quadrajet Power. And see if he can put together a kit with everything you need to convert carb to what you need. . He may have some extra information for you also. Also , stock intake, the trans cable plate will hit intake, can be bent up if you don’t need it Just make sure it totally clears so your accelorater doesn’t stick open getting lodged on intake
ok, ok.. I'll get the carb hahaha it was running fine with the Holley in there, well, fine for the use I give it anyway. There's no clearance issues or anything like that, I have plenty of space in that engine bay lol
