Factory jets and rods

[Joey85]

I was woundering what the factory specs is for 2 quadrajets
Also which one would be beter to rebuild for modifid 350.
17057202
17057253
Thanks

[Ethan1]

I was woundering what the factory specs is for 2 quadrajets
Also which one would be beter to rebuild for modifid 350.
17057202
17057253
Thanks

17057202- .077" Primary Jets, 52K Primary Metering Rods, "K" Secondary Hanger and CH Secondary Metering Rods.

17057253- .073" Primary Jets, 49K Primary Metering Rods, "K" Secondary Hanger and CV Secondary Metering Rods.

Either one sounds like a good candidate. Cliff would be best to answer. Just make sure you give the specs of your vehicle. Cam, engine, transmission, rear gears, etc.

[Joey85]

Thank you Ethan1

[Ethan1]

Thank you Ethan1

 

[Cliff Ruggles]

Those carburetors are basically equal from a performance standpoint.  I'd probably use the Chevy carb or at least put a short fuel filter housing on the Old's carb if it were used.

The end result from each would be the same, and both will need recalibrated for a "modified" 350 cid engine.

I would recommend converting to E-choke, HP quick release pull-off, idle system set up for the engine parameters, one of our rebuild kits, correct PP spring, and tuning components.......Cliff

[MG60]

Hi Ethan , could you please tell me the original internal specs (jets , hanger and rods) for this carby ;   7042270 .

[Ethan1]

Hi Ethan , could you please tell me the original internal specs (jets , hanger and rods) for this carby ;   7042270 .

 Stocks specs were .071" Primary Jets, 45 Primary Metering Rods, "K" Secondary Hanger and CR Secondary Metering Rods.

 Welcome to CHP, by the way!

[MG60]

Thanks very much Ethan1 , you are correct . Do you get your information from a book ?  If so can I buy a copy ?  Are there any changes you would make (normal street driving) to this (7042270) carby to run on modern fuel ?
Thanks , Tim . (Australia)

Also thanks to Cliff for introducing me to this site .

[MG60]

Can I have the internal original specs for these carbs please ;
7041270
7043270
7042240
7043240
7043262
7043266

Thanks , Tim .

[Ethan1]

Can I have the internal original specs for these carbs please ;
7041270
7043270
7042240
7043240
7043262
7043266

Thanks , Tim .

7041270- .074" Primary Jets, 43 Primary Metering Rods, "K" Secondary Hanger and BP Secondary Metering Rods.
7043270- .076" Primary Jets, 41 Primary Metering Rods, "K" Secondary Hanger and BV Secondary Metering Rods.
7042240- .073" Primary Jets, 48B Primary Metering Rods, "K" Secondary Hanger and CT Secondary Metering Rods.
7043240- .073" Primary Jets, 44B Primary Metering Rods, "K" Secondary Hanger and CT Secondary Metering Rods.
7043262- .071" Primary Jets, 41 Primary Metering Rods, "K" Secondary Hanger and CR Secondary Metering Rods.
7043266- .072" Primary Jets, 47C Primary Metering Rods, "K" Secondary Hanger and DB Secondary Metering Rods.

Keep in mind, there were variations. Not all had the same specs. Just the way it was back then.

[MG60]

Thanks Ethan1 . Next question , what was the carb number for the 1970 Pontiac 455 (H.O. 370hp) , and what were the internal specs ?

[Ethan1]

Thanks Ethan1 . Next question , what was the carb number for the 1970 Pontiac 455 (H.O. 370hp) , and what were the internal specs ?

 Automatic or Manual? California legal or non?

[MG60]

Automatic and Federal  ( 70402?? ) .

[Ethan1]

Automatic and Federal  ( 70402?? ) .

 7040268. .071" Primary Jets, 41 Primary Metering Rods, "K" Secondary Hanger and CC Secondary Metering Rods.

[MG60]

So there was no 7040270 carb in 1970 ?