Set up questions

[F250 Restorer]

Hello everyone.  This is my first post.  I am working on a little project:  installing a Q.jet on my hp FORD 300 I6, with about 250 hp.  The engine is .030 over, balanced, Isky 256 cam, Chrome rings, p&p head with over size sbc valves, shaved head and block= 9.3 c.r., header, Offenhauser 4v intake.

I currently have a Edelbrock 1403 (500 cfm) carb, but am unhappy with mpg and performance.  So I pulled a Q.J. off a 78 chevy van with a s.b.  It is a Cal. carb, for an auto trans. I got the kit from Cliff, with new idle tubes and air  bleeds to richen up the a/f.

Due to a thumb injury I have some time to think over the carb details, and was wondering where I should set the float.  I did not run the numbers of the engine I took it off.

Also, does anyone know if the mix screws in Cliff's kit need to have one coil cut off as he recommends in the  book, or should I install as is?

Thank you in advance.  I'm sure I'll find lots of great info here to prepare for the set up.

[omaha]

     The float is usually set at 1/4 inch and that seems to work. Some like to set it lower. I really dont know too many that revert to float settings as a tuning tool but some will argue that 1/4 is too high. Alright, if it makes you happy, try 9/32nds or even 5/16. I really dont see how this will affect anything too much. But, if you happened to loose the factory specs for some reason, (like I loose everything) the default setting at least for me is 1/4. I guess you could effect mixture but do you have a tool accurate enough to detect it? Over a wide range? Usually not.
    As far as the needles go, they should be able to seat to shut off the fuel or close to it.So, if the needles do not close the port all the way, because the springs coil bind first, yes trim a coil. If they do close the  port without the spring coil binding, they are fine. This has alot to do with the size of the idle port size (how big you may have drilled them). Anyway, welcome to the forum. HAVE FUN & ENJOY!!
(cool project BTW)

[F250 Restorer]

I'm just trying to make sure I installed the air bleeds restrictions in the correct location.  Pls let me know.

[omaha]

   Looks like you got it. Main air bleeds in both the top and main castings.

[F250 Restorer]

Thanks for the help, guys.  Since I have put the carb together, I notice I have an issue with the secondaries.  They bind just slightly at opening.  However, if I push in the s. shaft, on the spring side, they are free.

I did have a time getting the springs to work correctly, and now the shaft seems to move from side to side.  Any advice? 

Thanks in advance.

[F250 Restorer]

With my little engine, a 300 with 256 cam, should I enlarge the idle discharge ports before I install the carb?

Also, the secondary m.rods had a slight groove from sitting in the jets for so long.  I know this may sound stupid, but I'm guessing I should replace them or they may seep fuel?

Cliff, what do you think about the DR rods, and the G hanger? 

[omaha]

   hey f250 restorer, I think if you do enlarge the discharge ports slightly, it should not hurt anything. (.080-.090)
  the secondary rods do not "seat" in the permanent jet holes. they just kinda hang there. dont think it would hurt if there was slight wear in the rods but if you wanna get particular, go ahead and change them. the amount that they "hang" is determined by the hanger.  how far they are into the "taper" of the rod determines the "jetting" when the secondaries are first engaged.
 The DR rod is not a bad choice  and the hanger can be "adjusted". I doubt you will get past the 80 degree air valve opening with the 6 cylinder so I think the moderate taper should work good with the 6. youll probably end up experimenting with the hanger more so than the rods but I dont think it will be too far off.
   Another thing I was going to say was about that slight "bind". This is caused by the little spring sliding on the little shaft in the air valve flap tension adjustment area. sometime over time a slight burr develops on the little shaft or the spring might get some wear etc. change out the spring and smooth out the little shaft with some emory cloth. makes the flap nice and smooth when opening. (obviously the flap cant bind either.

[F250 Restorer]

Omaha and the rest of you guys who have helped, thanks so much.  Rebuilding this carb has really been an experience for me.  I'll be sure to mention this forum, and Cliff's help as well, in the up-coming article in True Blue Trucks magazine ... that is when I complete the build.

I read where a lot of the off road guys say to set the float level at 1/4".  In my kit it said the factory specs for this carb was 15/32", so I set it there.

Is there any reason I should use the real thick mounting gasket as opposed to a thin one?  I am having to use one of the funky spreadbore to squarebore adaptors, so I thought I'd use a thin gasket for heighth concerns, unless the thick one is needed b/c of v.leaks, etc.

Again, thanks for all the help.

[Cliff Ruggles]

The thicker gaskets act like an insulator to keep the carb cooler.  Not a big deal otherwise.  The most important thing is to make sure whatever you use seals it up without any vacuum leaks....Cliff