[Mr T81]

Hello all,

when I bought my car, '69 GP, there was a Holley 750 in it.
I want to try a Q-Jet. The engine is a 428, edelbrock performer
intake, 2.5" exhaust, cam close to stock. Altitude here is 2200ft.

Summit has Q-Jets for sell. Anybody has experience with them?
http://www.summitracing.com/search/p...%20Carburetors

Just wondering, is a 750cfm enough?

any input would be really appreciated, thanks

[altfueler]

Thank you for doing the RIGHT thing & putting a Q-jet back on top of that 428!

IMHO, Cliff Ruggles of Cliffs High Performance in Ohio ( 740-397-2921 ) is THE Man to get your Q-jet carbs & carb parts from.

Cliff wrote the book on Q-Jets.....LITERALLY!!

Cliff is very helpful on the phone & also posts here very often.

Good luck.

[rexs73gto]

Yes , cliff is the very best sourse for a great Q-jet, but if all you want is a correct Q-jet with the correct numbers ,,, if you know them , you can get a new replacement Q-jet from Johnsons Speed wharehouse, they have several hundreds of new in the box from GM Q-jets at a reasonable price. These you can bolt right on adjust & go. They bought about 10,000 of them from GM several year back & still have a lot of the numbers you may need. Check them out on the web under their name & you can get one in just a couple of days .

[69FIREBIRD76MM]

X-2 ON THE SUMMIT QUADRAJET.
H-K MOTORSPORTS has tested them on his dyno-motor and they work good, if you go thru ruggles waiting time is 6-10 months at least...Jet Performance has them too

[t money]

Try 67cruiser from this forum he playing around with q jets looks like he does nice work

[PONTIAC-ONE]

You may need to tune/calibrate one of the new or boxed rebuilt stock spec carbs though...just adding a slightly larger cam, small bump in compression gave my '74 Formula 400 a lean bog from a dead start.
I lived with that for years because I didn't know how to fix it 20 years ago.
I currently have a Cliff carb on my 455, no bogs, stumbles or traction until 3rd

[rexs73gto]

I had made several changes to my 73 GTO including heads, cam , headers & exhaust , & when I got my first one from Johnson's Speed wharehouse I bolted it on & it was very close that it only about 25 min's to figure it out & adjust it. Yes later I did put in different primary rods & some larger jets( 2 sizes up) but it did work out fine. Now the big plus if the get one from JSW it will be a front inlet as should be on a Pontiac, but the ones that are the tricked out units that summit & Eldorbock & the others sell as the tricked out & they are not new they are rebuilt, which is fine but It really is better to start with a new unit . And I don't know about you but I don't want a chevy rebuilt carb on my car. If it's chey put it on a chevy, & if I want something on my car I DEMAND that It be Pontiac or specially designed for a PONTIAC. Pontiac Rules. ,

[Mr T81]

Interesting comments, front fuel inlet is pretty important I guess.
I heard about Cliff's book and plan on getting one. But I cant wait
6 to 10 months for a carb. The Holley is not working properly and I
want to try a split bore carb. By the way, it does not really matter
to me if it's numbers matching or not.

[72LuxuryLeMansLa.]

Originally Posted by Mr T81

Interesting comments, front fuel inlet is pretty important I guess.
I heard about Cliff's book and plan on getting one. But I cant wait
6 to 10 months for a carb. The Holley is not working properly and I
want to try a split bore carb. By the way, it does not really matter
to me if it's numbers matching or not.

I called this guy and gave him the specs of my new build and he supposedly set up the carburetor accordingly. We shall see. I received the carburetor as promised and will use it on my new build. It looks great, every part has been refinished and it has the Adjustable Part Throttle.

http://www.smicarburetor.com/product.../productID/839

Karl

[Bruce Meyer]

Im pretty sure Cliff is the only rebuilder that properly fixes the leaky fuel well plugs on all Q-jets. Just putting epoxy over those plugs only lasts a year or so.

[ponjohn]

There is one for sale in the High perf section here.

[Cliff R]

I would avoid any commercially "remanufactured" carburetors from any source....FWIW.

I woln't even take them in the shop any more, pulled the plug on that deal recently. WAY too labor intensive, and the quality control just gets worse and worse on them.

Since my backlog of carb work usually exceeds one year, and my parts business is the main focus these days, I really don't have a "dog in the fight" so to speak, when it comes to making recommendations, giving advice, helping folks out with problems, etc. If I tell you someone, or someplace does poor quality work, it's not to steer anything in my direction.

There are at least half a dozen speciality shops offering q-jet rebuilding and restoration services these days, and at least twice that many "part timers" dabbling in the business when they aren't at their day job. Some of these shops due pathetic work, others OK, some fantastic, especially when it comes to the "cosmetic" aspect of the job. Most can get thru a "rebuild", but are completely clueless when it comes to setting up any particular unit for a custom application, or after engine modifications have been made to a stock application.

I know all this because at least 1/3rd of our work these days is taking a look at recent work from another source, that doesn't work well anyplace after the owner got it back. I actually like this work the best, as we don't have to do any cleaning, plating, bushing installation, etc. I can whip thru these jobs in a couple of hours, vs the 2 to 3 days it takes to do a full restoration with plated parts......Cliff

[1969GTO]

Cliff,
I don't mean to barge in......though
My question is Q-JETS [I have a Cliff Jet] and I see that you are also partaking in the STUMP PULLER thread.
Cliff have you noticed a common power valve spring or any thing special that you could advise on when using a Q-JET and the stump puller cam,either in an automatic or a stick car?
thank you for your time

[Cliff R]

It's going to depend on CID, compression ratio, and cam choice. If you provide me with the CID and compression ratio, I can specify a power piston spring that will work for what you are doing.....Cliff

[1969GTO]

Originally Posted by Cliff R

It's going to depend on CID, compression ratio, and cam choice. If you provide me with the CID and compression ratio, I can specify a power piston spring that will work for what you are doing.....Cliff

Cliff, my Q-JET [you had built for me when I had a differnt cam] is now the SDPERFORMANCE Stump Puller.
The engine is a 400/462,just under 10.1comp.
SDPERFORMANCE [Ruggles] cast intake.
RamAir Restorations Ram Air manifolds[ceramic coated]
2 1/2 XPYPES exhaust.
The carb is that later year Buick 800 cfm with the APT adjustment.
Just a note to those reading this, I too at one time bought a Q-JET from Jegs,it did have the chevy fuel inlet and the carb ran like crap.
I did send it to Cliff [6yrs ago-ish] and he had a list of things not done to the carb as to where half the carb was working. [it was a piece of junk]
Cliff did repair the carb and it was great. But just think of all the added xtra cost of buying a newly-rebuilt carb and having to send it out to be made right.
Cliff is worth the wait

[1969GTO]

Originally Posted by 1969GTO

Cliff, my Q-JET [you had built for me when I had a differnt cam] is now the SDPERFORMANCE Stump Puller.
The engine is a 400/462,just under 10.1comp.
SDPERFORMANCE [Ruggles] cast intake.
RamAir Restorations Ram Air manifolds[ceramic coated]
2 1/2 XPYPES exhaust.
The carb is that later year Buick 800 cfm with the APT adjustment.
Just a note to those reading this, I too at one time bought a Q-JET from Jegs,it did have the chevy fuel inlet and the carb ran like crap.
I did send it to Cliff [6yrs ago-ish] and he had a list of things not done to the carb as to where half the carb was working. [it was a piece of junk]
Cliff did repair the carb and it was great. But just think of all the added xtra cost of buying a newly-rebuilt carb and having to send it out to be made right.
Cliff is worth the wait

Cliff,any info on the spring?

[android 211]

Every time I type in 7029268 in ebay collector car parts one comes up. Unless your GP is a 4 speed, thats the right one for your car. They vary in price. There's a lot of them out there; they went on every standard engine 4 bbl automatic Pontiac in 69 with a 350, 400 or 428.

[Cliff R]

The quality control of the "remanufactured" carburetors has went from "pathetic" to "not worth two squirts of duck poop" in recent years. They have so many problems I could write a book on them in this response.

Instead, I'll just say that we don't want any sent here, and are no longer working on them for any reason. In the amount of time I spend trying to get them up to par, I could have built at least two original "virgin" units from the ground up and ended up with perfect results right off the bench.

The "reman's" are so "hacked" up these days, and the castings are soft from the acid bath they get, we're just "polishing turds" trying to get them up to par for the customer.

I would also recommend for anyone reading this to avoid the electric choke Marine units being offered on Ebay. They are nicely painted black mid to late 70's Caddillac cores that are WAY, WAY off the mark for any Marine application. Had a few end up here in the last year or so, and don't want to see any more of them either.

A guy is better off to get his own core, some good parts, and go after the deal himself, than to throw good hard earned money at some generic/commercially remanufactured POS......IMHO......Cliff

[Cliff R]

That application should make at least 11-12" vacuum at idle speed. I'd use the light blue spring that we have in our PP spring kit.....Cliff

[67cruiser]

I have my Marine Tex on my plugs for 3 yrs. now, showing no signs of coming off?? Maybe your using something differant?? I to check fuel wells with 30 psi of air and soapy water & never seen any marine tex leak as of yet( knock on wood) Great stuff for sure!!