Help with a remanufactured Carb. on my 69

[Scott G.]

A 69 427/390 I bought last year came with a remanufactured quadrajet #17059206 on it . The carb. appears to be completely rebuilt. I've got the timing,dwell and carb adjustments set about as good as I can get. It idles smooth, and runs good, but doesn't seem to get the torque or throttle response I'd exepect out of this engine. From what I can see from running the numbers this carb is comes from a 79 BB truck, also listed as an 350 application. My question is is this carb even an appropraite replacement for a 427/390 hp engine? I'm having a heckuva time finding a # 7029215 and wondering if I should slap a holley from a 66-67 on it until I can find a numbers matching? Any thoughts?

[Joe L.]

Re: Help with a remanufactured Carb. on my 69

A 69 427/390 I bought last year came with a remanufactured quadrajet #17059206 on it . The carb. appears to be completely rebuilt. I've got the timing,dwell and carb adjustments set about as good as I can get. It idles smooth, and runs good, but doesn't seem to get the torque or throttle response I'd exepect out of this engine. From what I can see from running the numbers this carb is comes from a 79 BB truck, also listed as an 350 application. My question is is this carb even an appropraite replacement for a 427/390 hp engine? I'm having a heckuva time finding a # 7029215 and wondering if I should slap a holley from a 66-67 on it until I can find a numbers matching? Any thoughts?

Scott-----


The original part number stamped on a carburetor means very little after the carb has been through a commercial rebuilding operation. The commercial rebuilder can reconfigure a lot of different cores into a finished, rebuilt carburetor for many other applications. In fact, all that may remain of the original carburetor is the float bowl (i.e. the part with the numbers stamped on it). With carburetors, there's not the same sort of parts interchangeability as there exists with other components (like alternators, starters, distributors, etc.) and interchanging components is a lot more "complex". Presumably, commercial rebuilders have the knowledge to do this.

Nevertheless, it's possible that in the interest of parts interchangeability the commercial rebuilder has made "compromises" that affect the performance of the carburetor. First thing, though, is that I'd want to be sure that the BOX that the carburetor was supplied in has a part number on it which you can confirm is the correct rebuilder' part number for your application.

One more thing: I have never found a commercially rebuilt carburetor that performed like a new carburetor or a carburetor that I rebuilt myself from a known, good core. A lot of times, the cores that commercial rebuilders use have been subject to prior abuse at the hands of some "klutz". Those sort of problems cannot be rebuilt out of a carburetor no matter what they do.

[Jack H.]

Re: Help with a remanufactured Carb. on my 69

Joe is spot on with his comments!

The selection of internal rods + jets DOES have an impact on the carb's performance silhouette and regardless of what's stamped on the air horn, that plus the integrity of mating surfaces can have a big effect...

But, before the poster 'discards' the 'driver' carb he has, perhaps a bit more detail on the issue of performance is in order... One thing that can have a DRAMATIC effect is how the secondary stage of a QJet is set up.

When configured improperly resulting in a secondary that doesn't open or doesn't open correctly, the car will 'dog' under max acceleration and pretty much fail to climb above roughly 4000 RPM. IF that's the symptom in question, a tweak here/there may well resolve the complaint!

[Dennis S.]

Re: Help with a remanufactured Carb. on my 69

Scott

I installed a NORS carb #17054917 on my car about 4 years ago. It is supposedly the correct service replacement and I decided that for a driver, it was the best choice. The carb that was on my car when I bought it was from a '67 passenger car and had a crack in the fuel inlet area. I paid around $800 including freight and it was shrink wrapped in the original box. Recently replaced the accelerator pump to improve performance.

Just for grins, I recently checked the following website:

www.Customrebuiltcarbs.com

They quoted me a rebuilt #7029215 for $1395 plus S & H. This particular carb was date coded around March '69. As stated in the above post, you have to consider that it is remanufactured and may not perform as well as a new service replacement. The choice is up to you.

Dennis

[Joe L.]

Re: Help with a remanufactured Carb. on my 69

Scott

I installed a NORS carb #17054917 on my car about 4 years ago. It is supposedly the correct service replacement and I decided that for a driver, it was the best choice. The carb that was on my car when I bought it was from a '67 passenger car and had a crack in the fuel inlet area. I paid around $800 including freight and it was shrink wrapped in the original box. Recently replaced the accelerator pump to improve performance.

Just for grins, I recently checked the following website:

www.Customrebuiltcarbs.com

They quoted me a rebuilt #7029215 for $1395 plus S & H. This particular carb was date coded around March '69. As stated in the above post, you have to consider that it is remanufactured and may not perform as well as a new service replacement. The choice is up to you.

Dennis

Dennis-----


Was the 17054917 number the one stamped on the carb or the number on a GM/Delco box?

[Paul H.]

Re: Help with a remanufactured Carb. on my 69

There are very few people that know how to correctly rebuild the Q-Jets. On my 68 427/390 I bolted on a Holley spreadbore (direct fit) and the car came to life. As was stated earlier, I'm not a big fan of the rebuilds. If it's a driver and not to be judged, the Holley works well.

[Joe C.]

Re: Help with a remanufactured Carb. on my 69

A 69 427/390 I bought last year came with a remanufactured quadrajet #17059206 on it . The carb. appears to be completely rebuilt. I've got the timing,dwell and carb adjustments set about as good as I can get. It idles smooth, and runs good, but doesn't seem to get the torque or throttle response I'd exepect out of this engine. From what I can see from running the numbers this carb is comes from a 79 BB truck, also listed as an 350 application. My question is is this carb even an appropraite replacement for a 427/390 hp engine? I'm having a heckuva time finding a # 7029215 and wondering if I should slap a holley from a 66-67 on it until I can find a numbers matching? Any thoughts?

The Q-Jet carburetor was only manufactured in TWO cfm ratings: 750 and 800. The 206 was a 750 cfm unit, used for smaller displacement engines, while the 215 was an 800 cfm unit used for larger displacement engines.

The symptoms of under carburation (flow capacity) is normally BETTER throttle response (due to smaller venturi) but with a peak power liability. Additionally, the spread bore Q-Jet is designed with small primary venturies for excellent throttle response.

I would not swap in a Holley, but, rather, tune this carburetor to deliver peak performance. The old fashioned way of reading spark plugs is not accurate, and will deliver quite different results depending on how much load was applied to the engine just prior to shutdown. There is no substitute, whatsoever, for using a wideband O2 sensor for monitoring air/fuel ratio in order to correctly "dial-in" your carburetor.

Unless your goal is to install an NCRS correct, numbers matching unit, I think that you would be happier, and save money, by matching jets/metering rods within the 206 to your application.........based on what the O2 sensor tells you. BTW, carburetor CFM ratings have nothing to do with air/fuel ratio, as you may know. The CFM rating only determines peak power output.

Here is a website that you will find useful:

http://www.digitalcorvettes.com/forums/showthread.php?t=88376

[Clem Z.]

Re: Help with a remanufactured Carb. on my 69

the 17059206 is a 350 truck carb with 72 jets and 52 primary rod and a secondary rod with a tip of .068. the 7029215 carb has 71 jets and 49 primary rod with a secondary metering rod with a tip of .040. so i would say you are running lean at wide open throttle

[Dennis S.]

Re: Help with a remanufactured Carb. on my 69

Dennis-----


Was the 17054917 number the one stamped on the carb or the number on a GM/Delco box?

Stamped on the carb.

[Joe L.]

Re: Help with a remanufactured Carb. on my 69

Stamped on the carb.

Dennis-----


I have no information that this carburetor part number was ever a part number for a SERVICE replacement for a 1969.

In general, the SERVICE part number for a carburetor is different than the part number actually stamped on the carburetor. The last available SERVICE part number for a 1969 L-36 was GM #7016925 and that carburetor did not carry the stamped number 17054917. The last available SERVICE carburetor for a 1969 350 was GM #7046904. That carburetor carried stamped number 7029207 (I have several NOS examples). The 7046904 replaced the 7016925 for SERVICE in 1974.

So, I don't know what a 17054917 is, but I don't think it's for any 1969 Corvette application. If this is a REBUILT carburetor, it is possible, though, that it has been reconfigured for a 1969 Corvette application, as I mentioned previously.

[Dennis S.]

Re: Help with a remanufactured Carb. on my 69

Dennis-----


I have no information that this carburetor part number was ever a part number for a SERVICE replacement for a 1969.

In general, the SERVICE part number for a carburetor is different than the part number actually stamped on the carburetor. The last available SERVICE part number for a 1969 L-36 was GM #7016925 and that carburetor did not carry the stamped number 17054917. The last available SERVICE carburetor for a 1969 350 was GM #7046904. That carburetor carried stamped number 7029207 (I have several NOS examples). The 7046904 replaced the 7016925 for SERVICE in 1974.

So, I don't know what a 17054917 is, but I don't think it's for any 1969 Corvette application. If this is a REBUILT carburetor, it is possible, though, that it has been reconfigured for a 1969 Corvette application, as I mentioned previously.

Joe

I am sure you are right. I think it is for a 1971 Chevy 454 manual truck application. I was told it was the correct CFM and that the characteristics and configuration would fit the car. I bought it because it was new and the price was right...the intact shrink wrap and black plastic tray were obviously original. By the way, the box that it was in had part #17054696...evidently means nothing. It is what it is.

[Clem Z.]

Re: Help with a remanufactured Carb. on my 69

17054917 carb is a replacement for 1971 402-454 cu in corvette,malibu and camaro according to the delco rochester bible. also trucks with the same engine

[Dennis S.]

Re: Help with a remanufactured Carb. on my 69

Thanks Clem. I feel better already.
The carb works great...after a recent .020 over complete rebuild and as near to stock as possible Comp Cam, the engine pulled 408 HP @ 5300 and 500 FT-LBS at 3100 on the engine dyno and we didn't mess with the jets or rods.

[Joe L.]

Re: Help with a remanufactured Carb. on my 69

Joe

I am sure you are right. I think it is for a 1971 Chevy 454 manual truck application. I was told it was the correct CFM and that the characteristics and configuration would fit the car. I bought it because it was new and the price was right...the intact shrink wrap and black plastic tray were obviously original. By the way, the box that it was in had part #17054696...evidently means nothing. It is what it is.

Dennis-----

GM #17054696 is the important number for me. That number is a late 1970's issued SERVICE carburetor for 1971 big block applications using Q-Jet carburetors, including 1971 Corvette LS-5. The 17054696 replaced GM #7047116 in June, 1977 and was discontinued without supercession in March, 1993.

I would expect that carburetor to be similar in configuration although somewhat different in "tuning" to the 1969 L-36 carb. There is probably a bit more "emissions control" built into it since all 1971 Q-Jet applications were for "controlled combustion emissions systems" rather than the "air injection reactor emissions system" used for 68-69 Corvette applications. With CCS, more of the exhaust emissions control is accomplished by carburetor and distributor calibration. However, if the carb's tuning turns out to be any sort of problem, installing revised jets and metering rods would likely completely cure it.

One thing this carb DEFINITELY has going for it is that it's a NEW carburetor. I would forsake other attributes anytime for that benefit. NOTHING makes a car run like a NEW carburetor. NOTHING!

[Dennis S.]

Re: Help with a remanufactured Carb. on my 69

Thanks Joe for the additional information. Your confirmation that I made the right choice is worth a lot. Hopefully Scott the OP has been helped in deciding what to do with his carb problem.