Author Topic: D shaped secondaries  (Read 1092 times)

Offline Stripes

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D shaped secondaries
« on: August 30, 2019, 08:45:43 AM »
Cliff,
I recently bought a car with a 1977 350 Pontiac engine that has a 17057262  0177  ARK Quadrajet on it. I purchased your performance rebuild kit for it, it only took a couple of days to get here. I recently rebuilt a 1968 carb with your kit that runs fantastically.

Researching this carb, I found posts or messages by you indicating this was a good performance carb you may have run on your 455? The secondaries have a chopped 0, or D format. I thought that was an indicator of a poor performance carb, and believed an earlier style round secondary type carb would be better?  Am I confusing this carb with another performance Rochester with the same number? Could this be an 800 CFM carb? And if it is a good carb, why would they put it on a very low performance, 7.6 to 1, 150hp 350 engine?

Offline Cliff Ruggles

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Re: D shaped secondaries
« Reply #1 on: August 30, 2019, 12:59:29 PM »
The 17057262 is far superior to the 1969 Pontiac carb in every respect. 

It converts easily to E-choke is one of them, and has APT. 

I don't know what you mean about "D" shaped secondaries, those were the intakes from 76-79, not the carbs....Cliff

Offline Stripes

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Re: D shaped secondaries
« Reply #2 on: August 30, 2019, 06:27:24 PM »
Oh. That's great! I didn't realize one of those black gaskets stuck to the carb and was D shaped. Ha. How far off are they jetted for a 455 with a 236/252@50 cam?

Offline Cliff Ruggles

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Re: D shaped secondaries
« Reply #3 on: September 01, 2019, 03:58:19 AM »
They will need more idle fuel and slight recalibration (jets/metering rods/pp spring) on the primary side.  Secondaries are WAY lean as they used DB rods in them. 

Easy things to correct during rebuilding and they don't need a lot of help anyplace else.

I recommend having us put together a custom rebuild kit with tuning parts.  We'll include an HP accl pump, high flow N/S assembly, idle tubes, jets, metering rods, PP spring, quick release choke pull-off and E-choke conversion (recommended).

Pretty much plug-n-play at that point, that's all that's ever been done to mine and it's been flawless now for decades.......Cliff

https://www.youtube.com/watch?v=6zVdoLR-VzM