laegion

i need some rebuild specs for a non-cc q-jet like the float adjustment, if anyone has their sheet from their rebuild kit and would like to scan it for me I would extremely appreciative!

I'm also curious what the brass device is in the bore next to the power piston, now don't assume i'm stupid, I just don't remember. and it's function isn't readily apparent.


please somebody has got to have this information, I just need to adjust things in the carb not rebuild it, since that was already done, they just didn't adjust anything right. so don't tell me to go buy a rebuild kit.

Thanks everyone!

Fast355

iTrader: (2)

Need the numbers off the carb for that. Sould be like a 70????? or 170?????.

The brass thing is the APT screw. You adjust it to limit how far the metering rods can go into the jets at cruise. That means you can change your cruise A/F ratio by changing the setting. Clockwise is leaner, counterclockwise is richer. I start them at 2 turns out from fully seated. I get pretty good gas mileage while cruising too. 15-18

Vader

No argument here. That's something that needs to be done to even a rebuilt, and many people overlook or don't understand that.

Perhaps if you could point out the part you are questioning, it would be easier:

laegion

on the highway?





Vader, I do believe that is not the model carb I have.

the number on mine is 17084226

fast 355 was right about the part I was curious about, i looked at it some more and I see how it limits the primary jets.

Fast355

iTrader: (2)

Average fuel economy is what I have seen over the last 3,000 miles in my full size G20 van with a 275 RWHP 350 and I drive pretty hard and constantly see 75-80 MPH on the highway. Basically a 5,300 lbs brick that isn't babied, darn good mileage if you ask me.

That carb is probably identical to mine just a year newer as I have a 17083226. Came off of my originol 305 HO in the van. It has 70 jets, 50M primary rod, about 8 in/hg spring, DR secondary rods and F hanger. Runs decent with lots of low and mid range torque on the primaries. Better than my 1405 edelbrock ever thought of being. Kick in the secondaries and that is where the Q-jet makes its performance. Keep your foot out of it and get great mileage.

laegion

ok, that is pretty good, I was scared you where talking about a thirdgen. lol

any ideas what the float should be set to? i just went and put gas in the carb and adjusted the float by eye so that it pushes the needle into the seat enough before it binds on the plastic cover thingie that it should be able to withstand some pressure, so I think it would be fine the gas level doesn't seem too high when the needle is in the seat. so I think it will work, but I'd like to double check it.


I used to have an 84 vandura 2500 with an lg4 and 3.42's that thing was soooo fun to drive, well for a van. I could never keep off of the gas, that's how I fell in love with carb roar. lol.


do you think 2 turns on the apt screw is more than enough for a 3400 lbs. vehicle compared to your van? i'm thinking like one and a half maybe, but what does everyone else have theirs set to? and how well does it work?

Fast355

iTrader: (2)

You might be able to go a little leaner on the APT due to less load at cruising speed. I went as lean as I could before it started bucking at cruise from being too lean. I went a 1/4 turn at a time in until it started bucking then backe out a 1/4 turn and that is how I ended up at 2. My A/F ratio gauge dissapears lean at cruise.

Actually an 84 vandura 305 is more like a L69 than a LG4. 350 cam, better heads, less restrictive exhaust, same carb calibration as L69, better advance curve. My van actaully came with 3.08 just has a 700r4 though. I had the 305 to begin with and like you could never keep off the gas. It was just too fun to outrun civics and integras. I could also outrun a buddies TBI 305 RS from a light if I wanted too.

Lo-tec

I just pulled out an old sheet and that # wasn't on it. I would try 15/32". Do you have the old float? Might want to measure that and set the new one the same.

Fast355

iTrader: (2)

My GP sorenson instructions from my last Q-jet rebuild say 13/32 on the float. Worked great on my engine as that is the same spec as mine.

laegion

yeah my van had a 700r4 too

I miss that van, I could actually beat some cars, lol, that and the nice starcraft conversion interior, well atleast it was nice till my friends started messing with stuff while I was driving, then it started to get more crappy. nice wood, and blue cloth interior and "mood" lighting and such.

now where do I measure from on the float? the end farthest from the pivot point? and then it's that distance to the top of the casting right?

Lo-tec

correct

Fast355

iTrader: (2)

Yes just make sure that you have the float contacting the needle and seat but not shoving it in real hard.

laegion

thank you all very much! the carb is now back together, and the apt screw is set to about 1.6 turns or so, hopefully it will work. i'll probably be trying to start it on wednesday

Fast355

iTrader: (2)

Hopefully it will work great for you. Although if it surges at part throttle you will know where to look.

laegion

yup, i'm hoping the difference in weight will make it work out at 1.6-1.65 or whatever it's at.

Fast355

iTrader: (2)

Then yours is also a 305 too right? Also did you notice which jets and metering rods you have?

laegion

i did notice primary metering rods

but i wasn't paying too much attention to the jets

the primaries are 51m

Sonix

iTrader: (1)

I emailed you a couple of q-jet articles for future reference.
If you want I can email you or post another q-jet rebuild sheet from a niehoff rebuild kit.

laegion

thank you

and yes that would be very helpful

Sonix

iTrader: (1)

It was too big to post, so I just emailed it to you. Hope thats the right carb.