Jets and rods after engine rebuild

[eightballz]

Hey guys,

heres my set-up. should i go bigger on the jets/rods/hangers etc? what modification would you do to the qjet?

- 455cui .030 over
- stock toronado low rise intake
- stock toronado exhaust manifolds
- stock dual exhaust
- stock Qjet 7040252: .070 primary jets, primary metering rods "520", secondary hanger "E", Secondary metering rods "AU"
- CR 10,25 : 1
- edelbrock alu heads - intake 2.125 exhaust 1.625
- Eagle H-Beam Connecting Rods 6735O3D
- ICON Premium Forged Pistons IC886-030 + Rings
- harland sharp 1.6 roller rocker
- Comp Cams Custom Ground hyraulic roller cam 232/236@.050 on a 114 - advanced 8°

thx

[Cliff Ruggles]

I would install our .071" jets and .043" tapered metering rods, employ the APT if you can get it out of the baseplate, and smaller DA secondary metering rods.  Put one of our kits in the carb, and we'll also supply a PP spring for what you are doing.....Cliff

[eightballz]

wow nice..thank you. sounds like a good starting point.

gonna check the ATP soon...but for now i'm struggling with the needle seat, which seems to be "pressed in"-style. its got 2 o-rings. now i know why setting the float level was such a pain in the rear!

i guess the threads were stripped so the rebuilder drilled it out.

time for a heli coil or better get a new bowl?

[429bbf]

i believe some carbs come that way . the 1967 buick i worked on had the same setup . cliffs kit had all the right stuff so i didn't need to do any modifying.fwiw

[Cliff Ruggles]

Correct, the carb has been commercially "remanufactured" at some point, and it's common for them to bore out the threads and install one of those POS pressed in deals....Cliff

[eightballz]

Correct, the carb has been commercially "remanufactured" at some point, and it's common for them to bore out the threads and install one of those POS pressed in deals....Cliff

any chance to "repair" this? like heli coil or use epoxy to install the threaded seat?

[Cliff Ruggles]

I would replace the casting, no real effective/affordable repair for that deal.  I have a machine shop that can bore out the casting and press in a threaded insert, very expensive operation and we only do that to save really rare and nearly impossible to find units....Cliff

[Marx3]

I once rebuild a 69 Cadillac unit that had that kind of seat. I installed the new screw-in seat by applying an epoxy-based body repair glue to the thread and putting it in.

I still holds up going almost 4 years. I dont know if this makes for a sollution worth suggesting, but it CAN be made to work.

[eightballz]

installed the jets and rods as suggested above..

after the performance rebuild on the 455 (now 461) you can guess that the idle circuit of my qjet won't allow enough air to flow for a decent idle w/o exposing the transfer slots etc.

to get around 800 RPM i need to open up the primaries wide enough to get nozzle drip.

i already ordered a set of drills etc. to open up idle air bypass and all the other stuff (i.e. idle tubes, bleeds etc.)

my plan is to close the primaries enough to stop nozzle drip and start from there...like not touching the slow idle screw during the process of modifying the idle circuit.

good idea?

float is set to 1/4" ...no flooding or any wet spots around the carb. you can tell that it needs more air by pulling a vac line on the intake..idle gains around 100 RPM and is smoothing out

[Cliff Ruggles]

It will need larger idle tubes, DCR's, and some additional idle bypass air for that cam.  Leave all the idle and main airbleeds stock.....Cliff

[eightballz]

all right..great info.

how large would you go?

[Cliff Ruggles]

Difficult question on any "reman".  Measure the idle airbleeds, if they are still the stock .070"/.070", I'd use .038" idle tubes and .055-.058" DCR's, with .110 bypass air.....Cliff