Quadrajets?

I did my senior thesis in college on hopoing up Q-jet carbs. (I was working on a Power & Transportation minor, and my senior auto tech class required a thesis project/paper) I did several carbs for students in the class after that an d they loved them. They are a bit fussier, and not as easily tuneable as a holley, but once that are set up, you really never have to touch a carb again, unless you are doing more engine mods. I like them, even though i currently am not running any. I could dig around and find the paper if you are interested, but it might take me a while to find it... that was 20 years ago!
PM me if you want me to look for it.

 

and where are these barrel's

 

Maybe I never had any of my Q-jets tuned up perfectly, but every car I ever had where I swapped a Holley to replace a Q-jet, the car just seemed to run way better with the Holley. More responsiveness. No flat spots. Holleys are easier to understand and easier to fix. Maybe Rochesters are just as good, but I think you have to be some sort of carburetor genius to really master them.

 

the q -jet on my 74 vette has been there since 1994 still runs great .the holley i had on my 60 vette is now sitting on a self where it appears to be working quite well.

 

My first rod had a 377 in it with two q-jets. I went looking for an intake and two different times I was told it wouldn't work. I ordered a new offy intake. I still have the intake and carbs if anyone wants I can get a picture. It Arrived at my doorstep with a casting date less than a week old so I know it was cast for me.

It ran like a scalded dog. I set it up with a progressive linkage. No bog at all. Of coarse I was running a 10in convertor and 4.11 gears. They are very reliable, get good milage, and IMHO a great sleeper carb. You can build an engine, paint the intake, run stock valve covers.....

Yeh nothing fancy about a q-jet. But fancy usually just means high maintianance.
Jeff

 

sure we want to see it

 

I'll snap a picture or two when I'm at the shop today.

 

I'd love to see a picture too. Thanks.

 

just about 10 minutes from here. He was going to throw them out cause he doesn't like them either. Neither one of us will use them so they just sit there maybe looking for a new home

 

Oh i'm sure we would take them

 

Bought one at a yard sale last year for six bucks and have been using it as a wheel chock for a freinds car since then.

 

Dual Q-jets on a Pontiac:http://forums.performanceyears.com/forums/attachment.php?attachmentid=76030&d=1166371186

Same engine, different view:http://forums.performanceyears.com/forums/attachment.php?attachmentid=76033&d=1166371347

 

cool, i have never seen before

 

Update: I checked at the only local salvage yard in town that has cars older than 20 yrs old, and he said he had few Q-Jets and wanted 25 bucks a piece, so I checked eBay; picked up a lot of three for 35 bucks. Also, picked up the Cliff Ruggles book on amazon (great book), and found out that he has a forum he appears to be trying to start where he answers questions personally: http://www.cliffshighperformance.com/simplemachinesforum/ .

 

thanks

 

I was a G.M. Master tech for 15 years--tune-up / drivability. I can't count how many Q-jets I've rebuilt. In my opinion, Q-jets are one of the best carbs--just pay attention to the few settings and play with the air bleeds / tubes, set the float just a little above stated settings, and crank a little more tension on the secondary air butterfly (top rear) and these things can make some power--and get some mileage,too. I've done tri-powers for myself and friends with Rochester 2 bbls, and they look good,but a good Q-jet runs WAY better.

 

Took me a while.... Here is my 2x4 setup. I had it on a 377 in a '40 chevy 2dr that was wrecked when someone pulled out in front of me in 1989.....



It is a home made linkage. I set it up to start opening the front carb when the secondary started opening on the rear. Then all 8 are fully open at the same time. It really worked good. I painted the carbs because the color didn't match to good between the two.

It is the low profile manifold....

 

yep,,never seen that

 

Been building them on boats for years. Never a problem set up right, great adjustability.

 

so you have any of those intakes ?

 

Here is one on eBay, if you happen to have a nailhead.
http://cgi.ebay.com/ebaymotors/Part...rms=39:1|65:10|240:1318&_trksid=p4506.c0.m245

 

I'm running a jet stage 2 800cfm qjet on the 502 in my tow rig. I didn't even have to adjust the idle mixture out of the box. I did have to adjust the tension on the air door slightly. It has all the drilling and epoxy work done. I don't get that great of mileage, but it's a 502 in a 80 dually pickup with 4.11's and a th400 so what do you expect. It starts good in the morning and pulls great with the race trailer on the back. I've always been an Edelbrock man, but I don't have any regrets with this carb choice.

I've only seen one dual qjet setup, it was a low-riser on a 396 in a 65 impala. The kid swore his dad ordered it from the factory that way. It was a cast iron intake. Anybody ever heard of this?

 

HAve rebuilt hundreds literly in the last 40 years. Even as late as two yearsago i was doing one or two perwek for my pals marine engine business. Before you get the drills out you should know you probably dont nned to. Many marine engines use Q JEts. marine engines are set up for full power sonce a marine engine never gets a rest like a highway engine it is under constant load . The marine versions have less vacuum fitting and such on them but are similar to say a 1705232 carb.
Carbs are very sensitve to float level , almost more so than jetttinng. Seconadry valve is adjustable for tension and secondary opening is also changable by simple modifying if the linkage. shortening the accel pump itself by 1/8 inch can make a quadrabog into a giant killer with no other mods. Good carbs well designed . Are more comlicated than a holley for the average bear but if your willing to leanr they will pay you qbck with good perfomance. Once did a back to back test with a friend using 750 carters vers qjets (Pair of 454s in cigar boat) Qjets much to our surprise outperfomed by 2 mph top end. Same day same water same boat same driver.

 

I ahve had them on a few different cars and I like them.The big Buick carb is awesome i think it is 800cfm.There is a guy in San Pedro,Ca that can tweak those things real good.There used to be a guy that lived by me when I was akid whose last name was Frisbee and he ran an ALtered and he was the quadrajet king.

 

is the marine carbs worth trying on the street ??