Cliff's Quadrajet Parts and Rebuild Kits

General Category => Quadrajet Carb Talk and Tips => Topic started by: Marx3 on May 25, 2015, 01:36:01 PM

Title: inventor of the Qjet
Post by: Marx3 on May 25, 2015, 01:36:01 PM

I came to thinking... the Qjet was such a great succes that GM used it on more or les all their cars from the late 60's up to 1990 ( ? ), but who invented it? who came up with this brilliant design in the first place? I am not talking about what company, Rochester obviously, but who? who is the person?

Title: Re: inventor of the Qjet
Post by: Ethan1 on May 27, 2015, 03:07:59 PM

The creator of the Rochester Quadrajet was by a man named Donald D. Stoltman. Which he created the Rochester Quadrajet in 1965. Actually, I believe he might have been the brains behind all models of the Rochester carburetors. Pretty smart man, to make a intriguing, well thought through carburetor. :)

Title: Re: inventor of the Qjet
Post by: Marx3 on May 28, 2015, 02:39:27 AM

Very interesting! Thanks :-) it seems he was involved in several patents
http://patents.justia.com/inventor/donald-d-stoltman

Title: Re: inventor of the Qjet
Post by: von on May 28, 2015, 02:45:46 AM

If you've ever had a Carter AFB apart, you'd see several similarities with a Q jet. It's like someone took some of those features like jet/metering rod combo, air valve secondaries, and larger secondary bores to a higher level.

Title: Re: inventor of the Qjet
Post by: Marx3 on May 28, 2015, 05:45:01 AM

I've had plenty of those apart, never thought much of them. They are "rough" by design I think.
I have always been aware of the obvious similarities. It is safe to say the Rochester took those details to a WHOLE new level :-)
Btw, the secondaries on the AFB aren't that much bigger than the primaries. I think the layout of the barrels is more like a Holley than a Qjet.

Title: Re: inventor of the Qjet
Post by: von on May 28, 2015, 06:31:24 AM

The one thing AFB's have that would've been good for high performance Q jet engines is the two needle and seat/float arrangement vs the Q jet's one. But of course would've made the Q jet bigger and bulkier.

Title: Re: inventor of the Qjet
Post by: Marx3 on May 30, 2015, 10:53:15 PM

Why do you think it would benefit from having 2 needle/seat's over 1?
I mean, the .135" seat supports 600 hp with out any problems ?

Title: Re: inventor of the Qjet
Post by: von on May 31, 2015, 02:32:56 AM

600 hp with a very good ($$) fuel system that can supply sufficient fuel volume. I'm just saying it would be a lot easier and cheaper to get enough fuel volume for 500-600 hp with two needles and seats. I know of a stock Chevelle fuel system that couldn't keep up with 400 hp and a tuned Q jet with .135 needle and seat.

Title: Re: inventor of the Qjet
Post by: Marx3 on June 02, 2015, 12:23:45 PM

oh yes yes, I see your point :-) Other than that, I cant think of any features that were left out.