17082292 Remanufactured by Holley- questions

[chevtech23]

Ive got a 17082292 Late model APT style carb, it has a label on it that says reads like the following:

577850
Holley   0774
Remanufactured
1904(70088)

It looked in nice shape so i tore into it to take some measurements, might use it on a project im working on

72 Jet, 51M primary rod .036 tip, the taper seems to run from .042 to .051
DR Secondary Rod, forgot to look at the hanger
Upper air bleed(Main body) .071 on the left, .072 on the right
Idle tubes: .045 on the left, .046 on the right
Idle down channel: .056 on the left, .057 on the right
Mixture screw Holes: .081
Idle bypass holes in throttle plate: .054
Accelerator pump discharge hole: .026

The idle tubes and down channel sizes seem off, is this thing calibrated for a big cam? What else did Holley do to these things and what time period did they sell them? Is it a giant turd? lol

Was thinking of using this on a mild 350, im still trying to get all the specs from the motor builder, it started out as a 95 LT1 short block, but was converted to a normal distibutor and has vortec heads. Has "just a bit bigger than stock" cam is what i was told, trying to get real numbers. It has an Edelbrock performer vortec dual plane intake. Motor is going into a 71 K10

Im not new to carbs but i am new to this level of detail on a Qjet. I want to get this thing close on the first try and im looking forward to recalibrating the idle and primary metering on this thing, any reccomendations?  I have some other cores to chose from, but im not sure if i have any more later apt cores and id like to use this one

Thanks in advance

[Cliff Ruggles]

Unfortunately Holley "remans" were among the worst out there.  Pretty common to find inconsistencies and very rich calibrations, plus the usual lead plugs driven into the bypass air holes in the main casting.

Drilling the throttle plates is a wasted effort on a late model unit with an idle bypass air system. 

Going to need much smaller idle tubes for sure, DCR's are pretty big as well.  I'd have to have the rest of the specs to be able to provide all the tuning parts needed for it to get it on par for what you are doing, including the LIAB and MAB sizes.

Replace the jets and metering rods as well, they are worn (common problem) down and we have a far superior custom "M" series rod for those that tapers from .050" all the way to .036" for improved control with the APT system........Cliff

[chevtech23]

Thanks for the reply, I found another core to use, its a 17085001. seems pretty fresh the idle mixture screws are still encased and the choke was riveted on, a good sign. opened it up and it measures as following

Jet-72 50M rod
Secondary EE rod
idle tube .038
down tube .045
Main Air bleed .052 (air horn)
Upper idle air bleed .070
Lower idle air bleed .062
Accel pump hole .024
I haven't released the idle mixture screws yet so I didn't measure the holes
Idle bypass air holes in throttle body .090

My question is on a mild 350 build do I want to plug the idle bypass air holes and redrill smaller? do I need to open up the lower idle air bleed?

[Cliff Ruggles]

Sounds like you have one of the heavy duty truck carburetors, most were on big block engines, very nice units.

Do not open up any airbleeds or close down bypass air, etc.  I'd do a complete stock rebuild with our SR kit and see how it works before modifying anything.  The little 350 with a slightly larger cam will like how it's set up.

One recommended change is to replace the 52M rods with our 52C rods for improved control with the APT system and put new jets in at the same time.  Those parts and always work some from many years of use.

We also have custom mixture screws that you can turn with a flat tip screwdriver and they are much longer for easy access as they stick out of the baseplate some........Cliff

[chevtech23]

Thanks, ill be placing an order, i dont see the 52m rods or the edelbrock performer base gasket mentioned elsewhere on the forum listed on the website, so ill call it in

Thank you

Matt

[Cliff Ruggles]

We sell a much better 50C rod instead that tapers from .050" all the way to the .036" tips.

We will put the correct base gasket in the kit....tks.....Cliff

[chevtech23]

ok, found the stuff on the website but $30 shipping seems steep, Also it wont let me specify what jets, tried to call no answer, help me out lol

[Cliff Ruggles]

If ordering multiple items best to call the shop.  If we don't answer leave a good number and message that you need parts and we will call you back......Cliff